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Editor’s Choice Articles

Editor’s Choice articles are based on recommendations by the scientific editors of MDPI journals from around the world. Editors select a small number of articles recently published in the journal that they believe will be particularly interesting to readers, or important in the respective research area. The aim is to provide a snapshot of some of the most exciting work published in the various research areas of the journal.

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24 pages, 10233 KiB  
Article
An Efficient Guiding Manager for Ground Mobile Robots in Agriculture
by Luis Emmi, Roemi Fernández and Pablo Gonzalez-de-Santos
Robotics 2024, 13(1), 6; https://doi.org/10.3390/robotics13010006 - 26 Dec 2023
Cited by 5 | Viewed by 2878
Abstract
Mobile robots have become increasingly important across various sectors and are now essential in agriculture due to their ability to navigate effectively and precisely in crop fields. Navigation involves the integration of several technologies, including robotics, control theory, computer vision, and artificial intelligence, [...] Read more.
Mobile robots have become increasingly important across various sectors and are now essential in agriculture due to their ability to navigate effectively and precisely in crop fields. Navigation involves the integration of several technologies, including robotics, control theory, computer vision, and artificial intelligence, among others. Challenges in robot navigation, particularly in agriculture, include mapping, localization, path planning, obstacle detection, and guiding control. Accurate mapping, localization, and obstacle detection are crucial for efficient navigation, while guiding the robotic system is essential to execute tasks accurately and for the safety of crops and the robot itself. Therefore, this study introduces a Guiding Manager for autonomous mobile robots specialized for laser-based weeding tools in agriculture. The focus is on the robot’s tracking, which combines a lateral controller, a spiral controller, and a linear speed controller to adjust to the different types of trajectories that are commonly followed in agricultural environments, such as straight lines and curves. The controllers have demonstrated their usefulness in different real work environments at different nominal speeds, validated on a tracked mobile platform with a width of about 1.48 m, in complex and varying field conditions including loose soil, stones, and humidity. The lateral controller presented an average absolute lateral error of approximately 0.076 m and an angular error of about 0.0418 rad, while the spiral controller presented an average absolute lateral error of about 0.12 m and an angular error of about 0.0103 rad, with a horizontal accuracy of about ±0.015 m and an angular accuracy of about ±0.009 rad, demonstrating its effectiveness in real farm tests. Full article
(This article belongs to the Special Issue Robotics and AI for Precision Agriculture)
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13 pages, 6271 KiB  
Article
GRI: General Reinforced Imitation and Its Application to Vision-Based Autonomous Driving
by Raphael Chekroun, Marin Toromanoff, Sascha Hornauer and Fabien Moutarde
Robotics 2023, 12(5), 127; https://doi.org/10.3390/robotics12050127 - 6 Sep 2023
Cited by 18 | Viewed by 2456
Abstract
Deep reinforcement learning (DRL) has been demonstrated to be effective for several complex decision-making applications, such as autonomous driving and robotics. However, DRL is notoriously limited by its high sample complexity and its lack of stability. Prior knowledge, e.g., as expert demonstrations, is [...] Read more.
Deep reinforcement learning (DRL) has been demonstrated to be effective for several complex decision-making applications, such as autonomous driving and robotics. However, DRL is notoriously limited by its high sample complexity and its lack of stability. Prior knowledge, e.g., as expert demonstrations, is often available but challenging to leverage to mitigate these issues. In this paper, we propose General Reinforced Imitation (GRI), a novel method which combines benefits from exploration and expert data and is straightforward to implement over any off-policy RL algorithm. We make one simplifying hypothesis: expert demonstrations can be seen as perfect data whose underlying policy gets a constant high reward. Based on this assumption, GRI introduces the notion of offline demonstration agent. This agent sends expert data which are processed both concurrently and indistinguishably with the experiences coming from the online RL exploration agent. We show that our approach enables major improvements on camera-based autonomous driving in urban environments. We further validate the GRI method on Mujoco continuous control tasks with different off-policy RL algorithms. Our method ranked first on the CARLA Leaderboard and outperforms World on Rails, the previous state-of-the-art method, by 17%. Full article
(This article belongs to the Topic Advances in Mobile Robotics Navigation, 2nd Volume)
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26 pages, 5199 KiB  
Article
A Passivity-Based Framework for Safe Physical Human–Robot Interaction
by Zhangchi Ding, Masoud Baghbahari and Aman Behal
Robotics 2023, 12(4), 116; https://doi.org/10.3390/robotics12040116 - 14 Aug 2023
Cited by 1 | Viewed by 2030
Abstract
In this paper, the problem of making a safe compliant contact between a human and an assistive robot is considered. Users with disabilities have a need to utilize their assistive robots for physical human–robot interaction (PHRI) during certain activities of daily living (ADLs). [...] Read more.
In this paper, the problem of making a safe compliant contact between a human and an assistive robot is considered. Users with disabilities have a need to utilize their assistive robots for physical human–robot interaction (PHRI) during certain activities of daily living (ADLs). Specifically, we propose a hybrid force/velocity/attitude control for a PHRI system based on measurements from a six-axis force/torque sensor mounted on the robot wrist. While automatically aligning the end-effector surface with the unknown environmental (human) surface, a desired commanded force is applied in the normal direction while following desired velocity commands in the tangential directions. A Lyapunov-based stability analysis is provided to prove both the convergence as well as passivity of the interaction to ensure both performance and safety. Simulation as well as experimental results verify the performance and robustness of the proposed hybrid controller in the presence of dynamic uncertainties as well as safe physical human–robot interactions for a kinematically redundant robotic manipulator. Full article
(This article belongs to the Section Humanoid and Human Robotics)
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25 pages, 5401 KiB  
Article
Finger Joint Stiffness Estimation with Joint Modular Soft Actuators for Hand Telerehabilitation
by Fuko Matsunaga, Shota Kokubu, Pablo Enrique Tortos Vinocour, Ming-Ta Ke, Ya-Hsin Hsueh, Shao Ying Huang, Jose Gomez-Tames and Wenwei Yu
Robotics 2023, 12(3), 83; https://doi.org/10.3390/robotics12030083 - 7 Jun 2023
Cited by 7 | Viewed by 2910
Abstract
In a telerehabilitation environment, it is difficult for a therapist to understand the condition of a patient’s finger joints because of the lack of direct assessment. In particular, not enabling the provision of spasticity evaluation significantly reduces the optimal performance of telerehabilitation. In [...] Read more.
In a telerehabilitation environment, it is difficult for a therapist to understand the condition of a patient’s finger joints because of the lack of direct assessment. In particular, not enabling the provision of spasticity evaluation significantly reduces the optimal performance of telerehabilitation. In a previous study, it has been proposed that finger stiffness could be estimated using an analytical model of a whole-finger soft actuator. However, because the whole-finger soft actuators require high air pressure for high bending performance and are costly to customize for each patient, using joint modular soft actuators for telerehabilitation turns to be a necessity, though stiffness estimation with joint modular soft actuators has not been studied yet. Another problem is caused by using a marker-based joint angle measurement, which requires the markers to be attached to the exact positions, and limits its application in telerehabilitation. In this study, we proposed a procedure of finger joint stiffness estimation that combines information acquired from a joint modular soft actuator and a marker-less hand joint position acquisition device. Correction parameters were added to the previous analytical model for -the bending analysis of a joint assisted using a joint modular soft actuator. Moreover, a multi-variate regression model was implemented for correcting joint angles obtained from the hand joint position acquisition device. As a result, a reasonable accuracy of stiffness estimation was achieved for rehabilitation with the joint modular soft actuators, which suggests the possibility of using the proposed method to evaluate the finger spasticity in a telerehabilitation environment. This is a big step forward towards optimal hand telerehabilitation. Full article
(This article belongs to the Special Issue The State-of-the-Art of Robotics in Asia)
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19 pages, 3392 KiB  
Article
A Trust-Assist Framework for Human–Robot Co-Carry Tasks
by Corey Hannum, Rui Li and Weitian Wang
Robotics 2023, 12(2), 30; https://doi.org/10.3390/robotics12020030 - 21 Feb 2023
Cited by 5 | Viewed by 2409
Abstract
Robots are increasingly being employed for diverse applications where they must work and coexist with humans. The trust in human–robot collaboration (HRC) is a critical aspect of any shared-task performance for both the human and the robot. The study of a human-trusting robot [...] Read more.
Robots are increasingly being employed for diverse applications where they must work and coexist with humans. The trust in human–robot collaboration (HRC) is a critical aspect of any shared-task performance for both the human and the robot. The study of a human-trusting robot has been investigated by numerous researchers. However, a robot-trusting human, which is also a significant issue in HRC, is seldom explored in the field of robotics. Motivated by this gap, we propose a novel trust-assist framework for human–robot co-carry tasks in this study. This framework allows the robot to determine a trust level for its human co-carry partner. The calculations of this trust level are based on human motions, past interactions between the human–robot pair, and the human’s current performance in the co-carry task. The trust level between the human and the robot is evaluated dynamically throughout the collaborative task, and this allows the trust to change if the human performs false positive actions, which can help the robot avoid making unpredictable movements and causing injury to the human. Additionally, the proposed framework can enable the robot to generate and perform assisting movements to follow human-carrying motions and paces when the human is considered trustworthy in the co-carry task. The results of our experiments suggest that the robot effectively assists the human in real-world collaborative tasks through the proposed trust-assist framework. Full article
(This article belongs to the Section Humanoid and Human Robotics)
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33 pages, 12704 KiB  
Review
Current Designs of Robotic Arm Grippers: A Comprehensive Systematic Review
by Jaime Hernandez, Md Samiul Haque Sunny, Javier Sanjuan, Ivan Rulik, Md Ishrak Islam Zarif, Sheikh Iqbal Ahamed, Helal Uddin Ahmed and Mohammad H Rahman
Robotics 2023, 12(1), 5; https://doi.org/10.3390/robotics12010005 - 2 Jan 2023
Cited by 37 | Viewed by 28002
Abstract
Recent technological advances enable gripper-equipped robots to perform many tasks traditionally associated with the human hand, allowing the use of grippers in a wide range of applications. Depending on the application, an ideal gripper design should be affordable, energy-efficient, and adaptable to many [...] Read more.
Recent technological advances enable gripper-equipped robots to perform many tasks traditionally associated with the human hand, allowing the use of grippers in a wide range of applications. Depending on the application, an ideal gripper design should be affordable, energy-efficient, and adaptable to many situations. However, regardless of the number of grippers available on the market, there are still many tasks that are difficult for grippers to perform, which indicates the demand and room for new designs to compete with the human hand. Thus, this paper provides a comprehensive review of robotic arm grippers to identify the benefits and drawbacks of various gripper designs. The research compares gripper designs by considering the actuation mechanism, degrees of freedom, grasping capabilities with multiple objects, and applications, concluding which should be the gripper design with the broader set of capabilities. Full article
(This article belongs to the Special Issue Kinematics and Robot Design V, KaRD2022)
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17 pages, 2443 KiB  
Article
Planar Model for Vibration Analysis of Cable Rehabilitation Robots
by Giacomo Zuccon, Alberto Doria, Matteo Bottin and Giulio Rosati
Robotics 2022, 11(6), 154; https://doi.org/10.3390/robotics11060154 - 18 Dec 2022
Cited by 6 | Viewed by 2165
Abstract
Cable robots are widely used in the field of rehabilitation. These robots differ from other cable robots because the cables are rather short and are usually equipped with magnetic hooks to improve the ease of use. The vibrations of rehabilitation robots are dominated [...] Read more.
Cable robots are widely used in the field of rehabilitation. These robots differ from other cable robots because the cables are rather short and are usually equipped with magnetic hooks to improve the ease of use. The vibrations of rehabilitation robots are dominated by the effects of the hooks and payloads, whereas the cables behave as massless springs. In this paper, a 2D model of the cables of a robot that simulates both longitudinal and transverse vibrations is developed and experimentally validated. Then the model is extended to simulate the vibrations of an actual 3D robot in the symmetry planes. Finally, the calculated modal properties (natural frequencies and modes of vibration) are compared with the typical spectrum of excitation due to the cable’s motion. Only the first transverse mode can be excited during the rehabilitation exercise. Full article
(This article belongs to the Special Issue Advanced Technologies in Rehabilitation Robots: Design, Control, and Human–Robot Interaction)
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12 pages, 2462 KiB  
Article
An Educational Test Rig for Kinesthetic Learning of Mechanisms for Underactuated Robotic Hands
by Gabriele Maria Achilli, Silvia Logozzo and Maria Cristina Valigi
Robotics 2022, 11(5), 115; https://doi.org/10.3390/robotics11050115 - 19 Oct 2022
Cited by 4 | Viewed by 2336
Abstract
Teaching robotics requires interdisciplinary skills and a good creativity, providing instructions and hands-on experiences, exploiting different kinds of learning. Two kinds of learning methods are commonly used: the ‘visual learning’ and the ‘auditory learning’, recognizable by the preference of an approach for images, [...] Read more.
Teaching robotics requires interdisciplinary skills and a good creativity, providing instructions and hands-on experiences, exploiting different kinds of learning. Two kinds of learning methods are commonly used: the ‘visual learning’ and the ‘auditory learning’, recognizable by the preference of an approach for images, rather than for texts, or oral explanations. A third possible learning style is the ‘kinesthetic learning’, based on tactile activities, which is generally least exploited, both by teachers in the classroom and by students during individual study. In this perspective, the use of educational test rigs is a good practice and adds an opportunity to share a passion for robotics. The paper focuses on the realization and application of an educational test rig aimed at explaining how a differential mechanism works and how it can be applied to robotic underactuated soft grippers to move multiple robotic fingers independently of each other using just a single actuator. The differential test bench was realized by 3D printing and mounted with the help of students in high school seminaries oriented to encourage students towards robotic or mechatronic studies. This activity was very thrilling for the students and helped them to approach robotics in a natural way, exploiting kinesthetic learning as it is demonstrated by test results. Full article
(This article belongs to the Special Issue Advances and Challenges in Educational Robotics II)
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19 pages, 7792 KiB  
Article
Development of an End-Effector Type Therapeutic Robot with Sliding Mode Control for Upper-Limb Rehabilitation
by Md Mahafuzur Rahaman Khan, Asif Al Zubayer Swapnil, Tanvir Ahmed, Md Mahbubur Rahman, Md Rasedul Islam, Brahim Brahmi, Raouf Fareh and Mohammad Habibur Rahman
Robotics 2022, 11(5), 98; https://doi.org/10.3390/robotics11050098 - 21 Sep 2022
Cited by 7 | Viewed by 4370
Abstract
Geriatric disorders, strokes, spinal cord injuries, trauma, and workplace injuries are all prominent causes of upper limb disability. A two-degrees-of-freedom (DoFs) end-effector type robot, iTbot (intelligent therapeutic robot) was designed to provide upper limb rehabilitation therapy. The non-linear control of iTbot utilizing modified [...] Read more.
Geriatric disorders, strokes, spinal cord injuries, trauma, and workplace injuries are all prominent causes of upper limb disability. A two-degrees-of-freedom (DoFs) end-effector type robot, iTbot (intelligent therapeutic robot) was designed to provide upper limb rehabilitation therapy. The non-linear control of iTbot utilizing modified sliding mode control (SMC) is presented in this paper. The chattering produced by a conventional SMC is undesirable for this type of robotic application because it damages the mechanical structure and causes discomfort to the robot user. In contrast to conventional SMC, our proposed method reduces chattering and provides excellent dynamic tracking performance, allowing rapid convergence of the system trajectory to its equilibrium point. The performance of the developed robot and controller was evaluated by tracking trajectories corresponding to conventional passive arm movement exercises, including several joints. According to the results of experiment, the iTbot demonstrated the ability to follow the desired trajectories effectively. Full article
(This article belongs to the Special Issue Kinematics and Robot Design V, KaRD2022)
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16 pages, 6286 KiB  
Article
Design of a Lightweight and Deployable Soft Robotic Arm
by Pierpaolo Palmieri, Matteo Melchiorre and Stefano Mauro
Robotics 2022, 11(5), 88; https://doi.org/10.3390/robotics11050088 - 31 Aug 2022
Cited by 14 | Viewed by 7295
Abstract
Soft robotics represents a rising trend in recent years, due to the ability to work in unstructured environments or in strict contact with humans. Introducing soft parts, robots can adapt to various contexts overcoming limits relative to the rigid structure of traditional ones. [...] Read more.
Soft robotics represents a rising trend in recent years, due to the ability to work in unstructured environments or in strict contact with humans. Introducing soft parts, robots can adapt to various contexts overcoming limits relative to the rigid structure of traditional ones. Main issues of soft robotics systems concern the relatively low force exertion and control complexity. Moreover, several fields of application, as space industry, need to develop novel lightweight and deployable robotic systems, that can be stored into a relatively small volume and deployed when required. In this paper, POPUP robot is introduced: a soft manipulator having inflatable links and rigid joints. Its hybrid structure aims to match the advantages of rigid robots and the useful properties of having a lightweight and deployable parts, ensuring simple control, low energy consumption and low compressed gas requirement. The first robot prototype and the system architecture are described highlighting design criteria and effect of internal pressure on the performances. A pseudo-rigid body model is used to describe the behavior of inflatable links looking forward to control design. Finally, the model is extended to the whole robot: multi-body simulations are performed to highlight the importance of suitable sensor equipment for control development, proposing a visual servoing solution. Full article
(This article belongs to the Special Issue Frontiers in Bionic and Flexible Robotics)
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22 pages, 5270 KiB  
Article
VLP Landmark and SLAM-Assisted Automatic Map Calibration for Robot Navigation with Semantic Information
by Yiru Wang, Babar Hussain and Chik Patrick Yue
Robotics 2022, 11(4), 84; https://doi.org/10.3390/robotics11040084 - 21 Aug 2022
Cited by 3 | Viewed by 3572
Abstract
With the rapid development of robotics and in-depth research of automatic navigation technology, mobile robots have been applied in a variety of fields. Map construction is one of the core research focuses of mobile robot development. In this paper, we propose an autonomous [...] Read more.
With the rapid development of robotics and in-depth research of automatic navigation technology, mobile robots have been applied in a variety of fields. Map construction is one of the core research focuses of mobile robot development. In this paper, we propose an autonomous map calibration method using visible light positioning (VLP) landmarks and Simultaneous Localization and Mapping (SLAM). A layout map of the environment to be perceived is calibrated by a robot tracking at least two landmarks mounted in the venue. At the same time, the robot’s position on the occupancy grid map generated by SLAM is recorded. The two sequences of positions are synchronized by their time stamps and the occupancy grid map is saved as a sensor map. A map transformation method is then performed to align the orientation of the two maps and to calibrate the scale of the layout map to agree with that of the sensor map. After the calibration, the semantic information on the layout map remains and the accuracy is improved. Experiments are performed in the robot operating system (ROS) to verify the proposed map calibration method. We evaluate the performance on two layout maps: one with high accuracy and the other with rough accuracy of the structures and scale. The results show that the navigation accuracy is improved by 24.6 cm on the high-accuracy map and 22.6 cm on the rough-accuracy map, respectively. Full article
(This article belongs to the Topic Intelligent Systems and Robotics)
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16 pages, 7877 KiB  
Article
Infrastructure-Aided Localization and State Estimation for Autonomous Mobile Robots
by Daniel Flögel, Neel Pratik Bhatt and Ehsan Hashemi
Robotics 2022, 11(4), 82; https://doi.org/10.3390/robotics11040082 - 18 Aug 2022
Cited by 11 | Viewed by 2608
Abstract
A slip-aware localization framework is proposed for mobile robots experiencing wheel slip in dynamic environments. The framework fuses infrastructure-aided visual tracking data (via fisheye lenses) and proprioceptive sensory data from a skid-steer mobile robot to enhance accuracy and reduce variance of the estimated [...] Read more.
A slip-aware localization framework is proposed for mobile robots experiencing wheel slip in dynamic environments. The framework fuses infrastructure-aided visual tracking data (via fisheye lenses) and proprioceptive sensory data from a skid-steer mobile robot to enhance accuracy and reduce variance of the estimated states. The slip-aware localization framework includes: the visual thread to detect and track the robot in the stereo image through computationally efficient 3D point cloud generation using a region of interest; and the ego motion thread which uses a slip-aware odometry mechanism to estimate the robot pose utilizing a motion model considering wheel slip. Covariance intersection is used to fuse the pose prediction (using proprioceptive data) and the visual thread, such that the updated estimate remains consistent. As confirmed by experiments on a skid-steer mobile robot, the designed localization framework addresses state estimation challenges for indoor/outdoor autonomous mobile robots which experience high-slip, uneven torque distribution at each wheel (by the motion planner), or occlusion when observed by an infrastructure-mounted camera. The proposed system is real-time capable and scalable to multiple robots and multiple environmental cameras. Full article
(This article belongs to the Special Issue Advances in Industrial Robotics and Intelligent Systems)
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23 pages, 3945 KiB  
Article
Constrained Reinforcement Learning for Vehicle Motion Planning with Topological Reachability Analysis
by Shangding Gu, Guang Chen, Lijun Zhang, Jing Hou, Yingbai Hu and Alois Knoll
Robotics 2022, 11(4), 81; https://doi.org/10.3390/robotics11040081 - 16 Aug 2022
Cited by 12 | Viewed by 3362
Abstract
Rule-based traditional motion planning methods usually perform well with prior knowledge of the macro-scale environments but encounter challenges in unknown and uncertain environments. Deep reinforcement learning (DRL) is a solution that can effectively deal with micro-scale unknown and uncertain environments. Nevertheless, DRL is [...] Read more.
Rule-based traditional motion planning methods usually perform well with prior knowledge of the macro-scale environments but encounter challenges in unknown and uncertain environments. Deep reinforcement learning (DRL) is a solution that can effectively deal with micro-scale unknown and uncertain environments. Nevertheless, DRL is unstable and lacks interpretability. Therefore, it raises a new challenge: how to combine the effectiveness and overcome the drawbacks of the two methods while guaranteeing stability in uncertain environments. In this study, a multi-constraint and multi-scale motion planning method is proposed for automated driving with the use of constrained reinforcement learning (RL), named RLTT, and comprising RL, a topological reachability analysis used for vehicle path space (TPS), and a trajectory lane model (TLM). First, a dynamic model of vehicles is formulated; then, TLM is developed on the basis of the dynamic model, thus constraining RL action and state space. Second, macro-scale path planning is achieved through TPS, and in the micro-scale range, discrete routing points are achieved via RLTT. Third, the proposed motion planning method is designed by combining sophisticated rules, and a theoretical analysis is provided to guarantee the efficiency of our method. Finally, related experiments are conducted to evaluate the effectiveness of the proposed method; our method can reduce 19.9% of the distance cost in the experiments as compared to the traditional method. Experimental results indicate that the proposed method can help mitigate the gap between data-driven and traditional methods, provide better performance for automated driving, and facilitate the use of RL methods in more fields. Full article
(This article belongs to the Section Intelligent Robots and Mechatronics)
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20 pages, 1631 KiB  
Review
A Perspective Review on Integrating VR/AR with Haptics into STEM Education for Multi-Sensory Learning
by Filippo Sanfilippo, Tomas Blazauskas, Gionata Salvietti, Isabel Ramos, Silviu Vert, Jaziar Radianti, Tim A. Majchrzak and Daniel Oliveira
Robotics 2022, 11(2), 41; https://doi.org/10.3390/robotics11020041 - 31 Mar 2022
Cited by 40 | Viewed by 12502
Abstract
As a result of several governments closing educational facilities in reaction to the COVID-19 pandemic in 2020, almost 80% of the world’s students were not in school for several weeks. Schools and universities are thus increasing their efforts to leverage educational resources and [...] Read more.
As a result of several governments closing educational facilities in reaction to the COVID-19 pandemic in 2020, almost 80% of the world’s students were not in school for several weeks. Schools and universities are thus increasing their efforts to leverage educational resources and provide possibilities for remote learning. A variety of educational programs, platforms, and technologies are now accessible to support student learning; while these tools are important for society, they are primarily concerned with the dissemination of theoretical material. There is a lack of support for hands-on laboratory work and practical experience. This is particularly important for all disciplines related to science, technology, engineering, and mathematics (STEM), where labs and pedagogical assets must be continuously enhanced in order to provide effective study programs. In this study, we describe a unique perspective to achieving multi-sensory learning through the integration of virtual and augmented reality (VR/AR) with haptic wearables in STEM education. We address the implications of a novel viewpoint on established pedagogical notions. We want to encourage worldwide efforts to make fully immersive, open, and remote laboratory learning a reality. Full article
(This article belongs to the Special Issue Intelligent Technologies and Robotics)
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17 pages, 5105 KiB  
Article
A Natural Language Interface for an Autonomous Camera Control System on the da Vinci Surgical Robot
by Maysara Elazzazi, Luay Jawad, Mohammed Hilfi and Abhilash Pandya
Robotics 2022, 11(2), 40; https://doi.org/10.3390/robotics11020040 - 25 Mar 2022
Cited by 9 | Viewed by 4457
Abstract
Positioning a camera during laparoscopic and robotic procedures is challenging and essential for successful operations. During surgery, if the camera view is not optimal, surgery becomes more complex and potentially error-prone. To address this need, we have developed a voice interface to an [...] Read more.
Positioning a camera during laparoscopic and robotic procedures is challenging and essential for successful operations. During surgery, if the camera view is not optimal, surgery becomes more complex and potentially error-prone. To address this need, we have developed a voice interface to an autonomous camera system that can trigger behavioral changes and be more of a partner to the surgeon. Similarly to a human operator, the camera can take cues from the surgeon to help create optimized surgical camera views. It has the advantage of nominal behavior that is helpful in most general cases and has a natural language interface that makes it dynamically customizable and on-demand. It permits the control of a camera with a higher level of abstraction. This paper shows the implementation details and usability of a voice-activated autonomous camera system. A voice activation test on a limited set of practiced key phrases was performed using both online and offline voice recognition systems. The results show an on-average greater than 94% recognition accuracy for the online system and 86% accuracy for the offline system. However, the response time of the online system was greater than 1.5 s, whereas the local system was 0.6 s. This work is a step towards cooperative surgical robots that will effectively partner with human operators to enable more robust surgeries. A video link of the system in operation is provided in this paper. Full article
(This article belongs to the Special Issue Advanced Technologies for Autonomous Surgical Robotics)
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43 pages, 68841 KiB  
Article
Mechanical Design and Analysis of a Novel Three-Legged, Compact, Lightweight, Omnidirectional, Serial–Parallel Robot with Compliant Agile Legs
by David Feller and Christian Siemers
Robotics 2022, 11(2), 39; https://doi.org/10.3390/robotics11020039 - 24 Mar 2022
Cited by 11 | Viewed by 9429
Abstract
In this work, the concept and mechanical design of a novel compact, lightweight, omnidirectional three-legged robot, featuring a hybrid serial–parallel topology including leg compliance is proposed. The proposal focusses deeply on the design aspects of the mechanical realisation of the robot based on [...] Read more.
In this work, the concept and mechanical design of a novel compact, lightweight, omnidirectional three-legged robot, featuring a hybrid serial–parallel topology including leg compliance is proposed. The proposal focusses deeply on the design aspects of the mechanical realisation of the robot based on its 3D-CAD assembly, while also discussing the results of multi-body simulations, exploring the characteristic properties of the mechanical system, regarding the locomotion feasibility of the robot model. Finally, a real-world prototype depicting a single robot leg is presented, which was built by highly leaning into a composite design, combining complex 3D-printed parts with stiff aluminium and polycarbonate parts, allowing for a mechanically dense and slim construction. Eventually, experiments on the prototype leg are demonstrated, showing the mechanical model operating in the real world. Full article
(This article belongs to the Section Sensors and Control in Robotics)
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17 pages, 4371 KiB  
Article
Dimensional Synthesis of a Novel 3-URU Translational Manipulator Implemented through a Novel Method
by Raffaele Di Gregorio
Robotics 2022, 11(1), 10; https://doi.org/10.3390/robotics11010010 - 5 Jan 2022
Cited by 3 | Viewed by 2860
Abstract
A dimensional synthesis of parallel manipulators (PMs) consists of determining the values of the geometric parameters that affect the platform motion so that a useful workspace with assigned sizes can be suitably located in a free-from-singularity region of its operational space. The main [...] Read more.
A dimensional synthesis of parallel manipulators (PMs) consists of determining the values of the geometric parameters that affect the platform motion so that a useful workspace with assigned sizes can be suitably located in a free-from-singularity region of its operational space. The main goal of this preliminary dimensioning is to keep the PM far enough from singularities to avoid high internal loads in the links and guarantee a good positioning precision (i.e., for getting good kinematic performances). This paper presents a novel method for the dimensional synthesis of translational PMs (TPMs) and applies it to a TPM previously proposed by the author. The proposed method, which is based on Jacobians’ properties, exploits the fact that TPM parallel Jacobians are block diagonal matrices to overcome typical drawbacks of indices based on Jacobian properties. The proposed method can be also applied to all the lower-mobility PMs with block diagonal Jacobians that separate platform rotations from platform translations (e.g., parallel wrists). Full article
(This article belongs to the Special Issue Kinematics and Robot Design IV, KaRD2021)
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14 pages, 82513 KiB  
Article
A Novel 3D Ring-Based Flapper Valve for Soft Robotic Applications
by Kelly Low, Devin R. Berg and Perry Y. Li
Robotics 2022, 11(1), 2; https://doi.org/10.3390/robotics11010002 - 22 Dec 2021
Cited by 1 | Viewed by 3954
Abstract
In this paper, the design and testing of a novel valve for the intuitive spatial control of soft or continuum manipulators are presented. The design of the valve is based on the style of a hydraulic flapper valve, but with simultaneous control of [...] Read more.
In this paper, the design and testing of a novel valve for the intuitive spatial control of soft or continuum manipulators are presented. The design of the valve is based on the style of a hydraulic flapper valve, but with simultaneous control of three pressure feed points, which can be used to drive three antagonistically arranged hydraulic actuators for positioning soft robots. The variable control orifices are arranged in a rotationally symmetric radial pattern to allow for an inline mounting configuration of the valve within the body of a manipulator. Positioning the valve ring at various 3D configurations results in different pressurizations of the actuators and corresponding spatial configurations of the manipulator. The design of the valve is suitable for miniaturization and use in applications with size constraints such as small soft manipulators and surgical robotics. Experimental validation showed that the performance of the valve can be reasonably modeled and can effectively drive an antagonistic arrangement of three actuators for soft manipulator control. Full article
(This article belongs to the Section Soft Robotics)
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19 pages, 6389 KiB  
Article
Feasibility and Performance Validation of a Leap Motion Controller for Upper Limb Rehabilitation
by Marcus R. S. B. de Souza, Rogério S. Gonçalves and Giuseppe Carbone
Robotics 2021, 10(4), 130; https://doi.org/10.3390/robotics10040130 - 4 Dec 2021
Cited by 7 | Viewed by 3595
Abstract
The leap motion controller is a commercial low-cost marker-less optical sensor that can track the motion of a human hand by recording various parameters. Upper limb rehabilitation therapy is the treatment of people having upper limb impairments, whose recovery is achieved through continuous [...] Read more.
The leap motion controller is a commercial low-cost marker-less optical sensor that can track the motion of a human hand by recording various parameters. Upper limb rehabilitation therapy is the treatment of people having upper limb impairments, whose recovery is achieved through continuous motion exercises. However, the repetitive nature of these exercises can be interpreted as boring or discouraging while patient motivation plays a key role in their recovery. Thus, serious games have been widely used in therapies for motivating patients and making the therapeutic process more enjoyable. This paper explores the feasibility, accuracy, and repeatability of a leap motion controller (LMC) to be applied in combination with a serious game for upper limb rehabilitation. Experimental feasibility tests are carried out by using an industrial robot that replicates the upper limb motions and is tracked by using an LMC. The results suggest a satisfactory performance in terms of tracking accuracy although some limitations are identified and discussed in terms of measurable workspace. Full article
(This article belongs to the Special Issue 10th Anniversary of Robotics—Feature Papers in Intelligent Robots and Mechatronics)
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25 pages, 13365 KiB  
Article
A Laser Vision System for Relative 3-D Posture Estimation of an Underwater Vehicle with Hemispherical Optics
by Christos C. Constantinou, George P. Georgiades and Savvas G. Loizou
Robotics 2021, 10(4), 126; https://doi.org/10.3390/robotics10040126 - 22 Nov 2021
Cited by 2 | Viewed by 3371
Abstract
This paper describes the development and experimental validation of algorithms for a novel laser vision system (LVS), suitable for measuring the relative posture from both solid and mesh-like targets in underwater environments. The system was developed in the framework of the AQUABOT project, [...] Read more.
This paper describes the development and experimental validation of algorithms for a novel laser vision system (LVS), suitable for measuring the relative posture from both solid and mesh-like targets in underwater environments. The system was developed in the framework of the AQUABOT project, a research project dedicated to the development of an underwater robotic system for inspection of offshore aquaculture installations. In particular, an analytical model for three-medium refraction that takes into account the nonlinear hemispherical optics for image rectification has been developed. The analytical nature of the model allows the online estimation of the refractive index of the external medium. The proposed LVS consists of three line-lasers within the field of view of the underwater robot camera. The algorithms that have been developed in this work provide appropriately filtered point-cloud datasets from each laser, as well as high-level information such as distance and relative orientation of the target with respect to the ROV. In addition, an automatic calibration procedure, along with the accompanying hardware for the underwater laser vision system has been developed to reduce the calibration overhead required by regular maintenance operations for underwater robots operating in seawater. Furthermore, a spatial image filter was developed for discriminating between mesh and non-mesh-like targets in the LVS measurements. Finally, a set of experiments was carried out in a controlled laboratory environment, as well as in real conditions at offshore aquaculture installations demonstrating the performance of the system. Full article
(This article belongs to the Special Issue Autonomous Marine Vehicles)
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32 pages, 4356 KiB  
Article
Unified Parameterization and Calibration of Serial, Parallel, and Hybrid Manipulators
by Benjamin L. Moser, Joshua A. Gordon and Andrew J. Petruska
Robotics 2021, 10(4), 124; https://doi.org/10.3390/robotics10040124 - 17 Nov 2021
Cited by 5 | Viewed by 4490
Abstract
In this work, we present methods allowing parallel, hybrid, and serial manipulators to be analyzed, calibrated, and controlled with the same analytical tools. We introduce a general approach to describe any robotic manipulator using established serial-link representations. We use this framework to generate [...] Read more.
In this work, we present methods allowing parallel, hybrid, and serial manipulators to be analyzed, calibrated, and controlled with the same analytical tools. We introduce a general approach to describe any robotic manipulator using established serial-link representations. We use this framework to generate analytical kinematic and calibration Jacobians for general manipulator constructions using null space constraints and extend the methods to hybrid manipulator types with complex geometry. We leverage the analytical Jacobians to develop detailed expressions for post-calibration pose uncertainties that are applied to describe the relationship between data set size and post-calibration uncertainty. We demonstrate the calibration of a hybrid manipulator assembled from high precision calibrated industrial components resulting in 91.1 μm RMS position error and 71.2 μrad RMS rotation error, representing a 46.7% reduction compared to the baseline calibration of assembly offsets. Full article
(This article belongs to the Topic Industrial Robotics)
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12 pages, 840 KiB  
Article
Untethered Origami Worm Robot with Diverse Multi-Leg Attachments and Responsive Motions under Magnetic Actuation
by Manivannan Sivaperuman Kalairaj, Catherine Jiayi Cai, Pavitra S and Hongliang Ren
Robotics 2021, 10(4), 118; https://doi.org/10.3390/robotics10040118 - 1 Nov 2021
Cited by 16 | Viewed by 5097
Abstract
Nowadays, origami folding in combination with actuation mechanisms can offer deployable structure design, yield compliance, and have several properties of soft material. An easy complex folding pattern can yield an array of functionalities in actuated hinges or active spring elements. This paper presents [...] Read more.
Nowadays, origami folding in combination with actuation mechanisms can offer deployable structure design, yield compliance, and have several properties of soft material. An easy complex folding pattern can yield an array of functionalities in actuated hinges or active spring elements. This paper presents various cylinder origami robot designs that can be untethered magnetically actuated. The different designs are analyzed and compared to achieve the following three types of motion: Peristaltic, rolling, and turning in different environments, namely, board, sandpaper, and sand. The proposed origami robot is able translate 53 mm in peristaltic motion within 20 s and is able to roll one complete cycle in 1 s and can turn ≈180∘ in 1.5 s. The robot also demonstrated a peristaltic locomotion at a speed of ≈2.5 mm s−1, ≈1.9 mm s−1, and ≈1.3 mm s−1 in board, sandpaper, and sand respectively; rolling motion at a speed of 1 cycle s−1, ≈0.66 cycles s−1, and ≈0.33 cycles s−1 in board, sandpaper, and sand respectively; and turning motion of ≈180∘, ≈83∘, and ≈58∘ in board, sandpaper, and sand respectively. The evaluation of the robotic motion and actuation is discussed in detail in this paper. Full article
(This article belongs to the Special Issue Robotics: 10th Anniversary Feature Papers)
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20 pages, 14233 KiB  
Review
A Suite of Robotic Solutions for Nuclear Waste Decommissioning
by Ivan Vitanov, Ildar Farkhatdinov, Brice Denoun, Francesca Palermo, Ata Otaran, Joshua Brown, Bukeikhan Omarali, Taqi Abrar, Miles Hansard, Changjae Oh, Stefan Poslad, Chen Liu, Hareesh Godaba, Ketao Zhang, Lorenzo Jamone and Kaspar Althoefer
Robotics 2021, 10(4), 112; https://doi.org/10.3390/robotics10040112 - 7 Oct 2021
Cited by 26 | Viewed by 8105
Abstract
Dealing safely with nuclear waste is an imperative for the nuclear industry. Increasingly, robots are being developed to carry out complex tasks such as perceiving, grasping, cutting, and manipulating waste. Radioactive material can be sorted, and either stored safely or disposed of appropriately, [...] Read more.
Dealing safely with nuclear waste is an imperative for the nuclear industry. Increasingly, robots are being developed to carry out complex tasks such as perceiving, grasping, cutting, and manipulating waste. Radioactive material can be sorted, and either stored safely or disposed of appropriately, entirely through the actions of remotely controlled robots. Radiological characterisation is also critical during the decommissioning of nuclear facilities. It involves the detection and labelling of radiation levels, waste materials, and contaminants, as well as determining other related parameters (e.g., thermal and chemical), with the data visualised as 3D scene models. This paper overviews work by researchers at the QMUL Centre for Advanced Robotics (ARQ), a partner in the UK EPSRC National Centre for Nuclear Robotics (NCNR), a consortium working on the development of radiation-hardened robots fit to handle nuclear waste. Three areas of nuclear-related research are covered here: human–robot interfaces for remote operations, sensor delivery, and intelligent robotic manipulation. Full article
(This article belongs to the Special Issue Advances in Robots for Hazardous Environments in the UK)
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21 pages, 4202 KiB  
Article
A Robot Architecture Using ContextSLAM to Find Products in Unknown Crowded Retail Environments
by Daniel Dworakowski, Christopher Thompson, Michael Pham-Hung and Goldie Nejat
Robotics 2021, 10(4), 110; https://doi.org/10.3390/robotics10040110 - 26 Sep 2021
Cited by 10 | Viewed by 4508
Abstract
Grocery shoppers must negotiate cluttered, crowded, and complex store layouts containing a vast variety of products to make their intended purchases. This complexity may prevent even experienced shoppers from finding their grocery items, consuming a lot of their time and resulting in monetary [...] Read more.
Grocery shoppers must negotiate cluttered, crowded, and complex store layouts containing a vast variety of products to make their intended purchases. This complexity may prevent even experienced shoppers from finding their grocery items, consuming a lot of their time and resulting in monetary loss for the store. To address these issues, we present a generic grocery robot architecture for the autonomous search and localization of products in crowded dynamic unknown grocery store environments using a unique context Simultaneous Localization and Mapping (contextSLAM) method. The contextSLAM method uniquely creates contextually rich maps through the online fusion of optical character recognition and occupancy grid information to locate products and aid in robot localization in an environment. The novelty of our robot architecture is in its ability to intelligently use geometric and contextual information within the context map to direct robot exploration in order to localize products in unknown environments in the presence of dynamic people. Extensive experiments were conducted with a mobile robot to validate the overall architecture and contextSLAM, including in a real grocery store. The results of the experiments showed that our architecture was capable of searching for and localizing all products in various grocery lists in different unknown environments. Full article
(This article belongs to the Special Issue 10th Anniversary of Robotics—Feature Papers in Intelligent Robots and Mechatronics)
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16 pages, 2466 KiB  
Article
Smart Cleaner: A New Autonomous Indoor Disinfection Robot for Combating the COVID-19 Pandemic
by Kaicheng Ruan, Zehao Wu and Qingsong Xu
Robotics 2021, 10(3), 87; https://doi.org/10.3390/robotics10030087 - 12 Jul 2021
Cited by 44 | Viewed by 13991
Abstract
The COVID-19 pandemic imposes an increasing demand for service robots as a substitute for humans to conduct various types of work in contaminated areas. Such work includes logistics, patient care, and disinfection, which can reduce the risk of human exposure to the highly [...] Read more.
The COVID-19 pandemic imposes an increasing demand for service robots as a substitute for humans to conduct various types of work in contaminated areas. Such work includes logistics, patient care, and disinfection, which can reduce the risk of human exposure to the highly contagious and deadly virus. This paper presents the design and development of Smart Cleaner, which is a new cost-effective autonomous indoor disinfection robot. It integrates a wheeled mobile robot platform and a hydrogen peroxide atomization device for automated disinfection operation in the complex indoor environment. Through the system integration of various hardware components and software programming, a prototype of the disinfection robot has been fabricated for experimental investigation. A simulation study of the drymist hydrogen peroxide disinfection model was carried out to understand the diffusion of disinfectant in a room environment. The effectiveness of the developed robot was verified in practical scenarios, such as hospital, hotel, office, and laboratory. The effect of disinfection was validated by a qualified third-party testing agency. Results demonstrate the high efficiency of the developed disinfection robot dedicated to autonomous indoor disinfection work. Full article
(This article belongs to the Special Issue Service Robotics against COVID-2019 Pandemic)
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21 pages, 2403 KiB  
Article
On the Modelling of Tethered Mobile Robots as Redundant Manipulators
by Matteo Caruso, Paolo Gallina and Stefano Seriani
Robotics 2021, 10(2), 81; https://doi.org/10.3390/robotics10020081 - 12 Jun 2021
Cited by 9 | Viewed by 5262
Abstract
Controlling a chain of tethered mobile robots (TMRs) can be a challenging task. This kind of system can be considered kinematically as an open-chain robotic arm where the mobile robots are considered as a revolute joint and the tether is considered as a [...] Read more.
Controlling a chain of tethered mobile robots (TMRs) can be a challenging task. This kind of system can be considered kinematically as an open-chain robotic arm where the mobile robots are considered as a revolute joint and the tether is considered as a variable length link, using a prismatic joint. Thus, the TMRs problem is decoupled into two parallel problems: the equivalent robotic manipulator control and the tether shape computation. Kinematic redundancy is exploited in order to coordinate the motion of all mobile robots forming the chain, expressing the constraints acting on the mobile robots as secondary tasks for the equivalent robotic arm. Implementation in the Gazebo simulation environment shows that the methodology is capable of controlling the chain of TMRs in cluttered environments. Full article
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20 pages, 6282 KiB  
Article
A Method for Health Indicator Evaluation for Condition Monitoring of Industrial Robot Gears
by Corbinian Nentwich and Gunther Reinhart
Robotics 2021, 10(2), 80; https://doi.org/10.3390/robotics10020080 - 9 Jun 2021
Cited by 12 | Viewed by 5732
Abstract
Condition monitoring of industrial robots has the potential to decrease downtimes in highly automated production systems. In this context, we propose a new method to evaluate health indicators for this application and suggest a new health indicator (HI) based on vibration data measurements, [...] Read more.
Condition monitoring of industrial robots has the potential to decrease downtimes in highly automated production systems. In this context, we propose a new method to evaluate health indicators for this application and suggest a new health indicator (HI) based on vibration data measurements, Short-time Fourier transform and Z-scores. By executing the method, we find that the proposed health indicator can detect varying faults better, has lower temperature sensitivity and works better in instationary velocity regimes compared to several state-of-the-art HIs. A discussion of the validity of the results concludes our contribution. Full article
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23 pages, 4909 KiB  
Article
Coordination of Multiple Robotic Vehicles in Obstacle-Cluttered Environments
by Charalampos P. Bechlioulis, Panagiotis Vlantis and Kostas J. Kyriakopoulos
Robotics 2021, 10(2), 75; https://doi.org/10.3390/robotics10020075 - 22 May 2021
Cited by 4 | Viewed by 4628
Abstract
In this work, we consider the motion control problem for a platoon of unicycle robots operating within an obstacle-cluttered workspace. Each robot is equipped with a proximity sensor that allows it to perceive nearby obstacles as well as a camera to obtain its [...] Read more.
In this work, we consider the motion control problem for a platoon of unicycle robots operating within an obstacle-cluttered workspace. Each robot is equipped with a proximity sensor that allows it to perceive nearby obstacles as well as a camera to obtain its relative position with respect to its preceding robot. Additionally, no robot other than the leader of the team is able to localize itself within the workspace and no centralized communication network exists, i.e., explicit information exchange between the agents is unavailable. To tackle this problem, we adopt a leader–follower architecture and propose a novel, decentralized control law for each robot-follower, based on the Prescribed Performance Control method, which guarantees collision-free tracking and visual connectivity maintenance by ensuring that each follower maintains its predecessor within its camera field of view while keeping static obstacles out of the line of sight for all time. Finally, we verify the efficacy of the proposed control scheme through extensive simulations. Full article
(This article belongs to the Special Issue Multi-Robot Systems: From Theoretical Contributions to Practical Applications)
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14 pages, 4135 KiB  
Article
Design of PEIS: A Low-Cost Pipe Inspector Robot
by Mario Mauro Salvatore, Alessio Galloro, Leonardo Muzzi, Giovanni Pullano, Péter Odry and Giuseppe Carbone
Robotics 2021, 10(2), 74; https://doi.org/10.3390/robotics10020074 - 19 May 2021
Cited by 8 | Viewed by 5785
Abstract
This paper outlines the design of a novel mechatronic system for semi-automatic inspection and white-water in-pipe obstruction removals without the need for destructive methods or specialized manpower. The device is characterized by a lightweight structure and high transportability. It is composed by a [...] Read more.
This paper outlines the design of a novel mechatronic system for semi-automatic inspection and white-water in-pipe obstruction removals without the need for destructive methods or specialized manpower. The device is characterized by a lightweight structure and high transportability. It is composed by a front, a rear and a central module that realize the worm-like locomotion of the robot with a specifically designed driving mechanism for the straight motion of the robot along the pipeline. The proposed mechatronic system is easily adaptable to pipes of various sizes. Each module is equipped with a motor that actuates three slider-crank-based mechanisms. The central module incorporates a length-varying mechanism that allows forward and backward locomotion. The device is equipped with specific low-cost sensors that allow an operator to monitor the device and locate an obstruction in real time. The movement of the device can be automatic or controlled manually by using a specific user-friendly control board and a laptop. Preliminary laboratory tests are reported to demonstrate the engineering feasibility and effectiveness of the proposed design, which is currently under patenting. Full article
(This article belongs to the Special Issue Advances in Italian Robotics II)
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29 pages, 809 KiB  
Article
An Overview of Verification and Validation Challenges for Inspection Robots
by Michael Fisher, Rafael C. Cardoso, Emily C. Collins, Christopher Dadswell, Louise A. Dennis, Clare Dixon, Marie Farrell, Angelo Ferrando, Xiaowei Huang, Mike Jump, Georgios Kourtis, Alexei Lisitsa, Matt Luckcuck, Shan Luo, Vincent Page, Fabio Papacchini and Matt Webster
Robotics 2021, 10(2), 67; https://doi.org/10.3390/robotics10020067 - 29 Apr 2021
Cited by 34 | Viewed by 10556
Abstract
The advent of sophisticated robotics and AI technology makes sending humans into hazardous and distant environments to carry out inspections increasingly avoidable. Being able to send a robot, rather than a human, into a nuclear facility or deep space is very appealing. However, [...] Read more.
The advent of sophisticated robotics and AI technology makes sending humans into hazardous and distant environments to carry out inspections increasingly avoidable. Being able to send a robot, rather than a human, into a nuclear facility or deep space is very appealing. However, building these robotic systems is just the start and we still need to carry out a range of verification and validation tasks to ensure that the systems to be deployed are as safe and reliable as possible. Based on our experience across three research and innovation hubs within the UK’s “Robots for a Safer World” programme, we present an overview of the relevant techniques and challenges in this area. As the hubs are active across nuclear, offshore, and space environments, this gives a breadth of issues common to many inspection robots. Full article
(This article belongs to the Special Issue Advances in Robots for Hazardous Environments in the UK)
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20 pages, 2325 KiB  
Article
Validating Safety in Human–Robot Collaboration: Standards and New Perspectives
by Marcello Valori, Adriano Scibilia, Irene Fassi, José Saenz, Roland Behrens, Sebastian Herbster, Catherine Bidard, Eric Lucet, Alice Magisson, Leendert Schaake, Jule Bessler, Gerdienke B. Prange-Lasonder, Morten Kühnrich, Aske B. Lassen and Kurt Nielsen
Robotics 2021, 10(2), 65; https://doi.org/10.3390/robotics10020065 - 29 Apr 2021
Cited by 53 | Viewed by 11911
Abstract
Human–robot collaboration is currently one of the frontiers of industrial robot implementation. In parallel, the use of robots and robotic devices is increasing in several fields, substituting humans in “4D”—dull, dirty, dangerous, and delicate—tasks, and such a trend is boosted by the recent [...] Read more.
Human–robot collaboration is currently one of the frontiers of industrial robot implementation. In parallel, the use of robots and robotic devices is increasing in several fields, substituting humans in “4D”—dull, dirty, dangerous, and delicate—tasks, and such a trend is boosted by the recent need for social distancing. New challenges in safety assessment and verification arise, due to both the closer and closer human–robot interaction, common for the different application domains, and the broadening of user audience, which is now very diverse. The present paper discusses a cross-domain approach towards the definition of step-by-step validation procedures for collaborative robotic applications. To outline the context, the standardization framework is analyzed, especially from the perspective of safety testing and assessment. Afterwards, some testing procedures based on safety skills, developed within the framework of the European project COVR, are discussed and exemplary presented. Full article
(This article belongs to the Special Issue Human–Robot Collaboration)
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31 pages, 54526 KiB  
Review
Advances in Agriculture Robotics: A State-of-the-Art Review and Challenges Ahead
by Luiz F. P. Oliveira, António P. Moreira and Manuel F. Silva
Robotics 2021, 10(2), 52; https://doi.org/10.3390/robotics10020052 - 24 Mar 2021
Cited by 211 | Viewed by 33211
Abstract
The constant advances in agricultural robotics aim to overcome the challenges imposed by population growth, accelerated urbanization, high competitiveness of high-quality products, environmental preservation and a lack of qualified labor. In this sense, this review paper surveys the main existing applications of agricultural [...] Read more.
The constant advances in agricultural robotics aim to overcome the challenges imposed by population growth, accelerated urbanization, high competitiveness of high-quality products, environmental preservation and a lack of qualified labor. In this sense, this review paper surveys the main existing applications of agricultural robotic systems for the execution of land preparation before planting, sowing, planting, plant treatment, harvesting, yield estimation and phenotyping. In general, all robots were evaluated according to the following criteria: its locomotion system, what is the final application, if it has sensors, robotic arm and/or computer vision algorithm, what is its development stage and which country and continent they belong. After evaluating all similar characteristics, to expose the research trends, common pitfalls and the characteristics that hinder commercial development, and discover which countries are investing into Research and Development (R&D) in these technologies for the future, four major areas that need future research work for enhancing the state of the art in smart agriculture were highlighted: locomotion systems, sensors, computer vision algorithms and communication technologies. The results of this research suggest that the investment in agricultural robotic systems allows to achieve short—harvest monitoring—and long-term objectives—yield estimation. Full article
(This article belongs to the Special Issue Advances in Agriculture and Forest Robotics)
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27 pages, 7718 KiB  
Article
Motion Planning and Control of an Omnidirectional Mobile Robot in Dynamic Environments
by Mahmood Reza Azizi, Alireza Rastegarpanah and Rustam Stolkin
Robotics 2021, 10(1), 48; https://doi.org/10.3390/robotics10010048 - 17 Mar 2021
Cited by 38 | Viewed by 9751
Abstract
Motion control in dynamic environments is one of the most important problems in using mobile robots in collaboration with humans and other robots. In this paper, the motion control of a four-Mecanum-wheeled omnidirectional mobile robot (OMR) in dynamic environments is studied. The robot’s [...] Read more.
Motion control in dynamic environments is one of the most important problems in using mobile robots in collaboration with humans and other robots. In this paper, the motion control of a four-Mecanum-wheeled omnidirectional mobile robot (OMR) in dynamic environments is studied. The robot’s differential equations of motion are extracted using Kane’s method and converted to discrete state space form. A nonlinear model predictive control (NMPC) strategy is designed based on the derived mathematical model to stabilize the robot in desired positions and orientations. As a main contribution of this work, the velocity obstacles (VO) approach is reformulated to be introduced in the NMPC system to avoid the robot from collision with moving and fixed obstacles online. Considering the robot’s physical restrictions, the parameters and functions used in the designed control system and collision avoidance strategy are determined through stability and performance analysis and some criteria are established for calculating the best values of these parameters. The effectiveness of the proposed controller and collision avoidance strategy is evaluated through a series of computer simulations. The simulation results show that the proposed strategy is efficient in stabilizing the robot in the desired configuration and in avoiding collision with obstacles, even in narrow spaces and with complicated arrangements of obstacles. Full article
(This article belongs to the Special Issue Selected Papers from the 7th Modelling and Simulation for Autonomous Systems Conference (MESAS 2020))
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47 pages, 19996 KiB  
Review
Service Robots in the Healthcare Sector
by Jane Holland, Liz Kingston, Conor McCarthy, Eddie Armstrong, Peter O’Dwyer, Fionn Merz and Mark McConnell
Robotics 2021, 10(1), 47; https://doi.org/10.3390/robotics10010047 - 11 Mar 2021
Cited by 142 | Viewed by 43727
Abstract
Traditionally, advances in robotic technology have been in the manufacturing industry due to the need for collaborative robots. However, this is not the case in the service sectors, especially in the healthcare sector. The lack of emphasis put on the healthcare sector has [...] Read more.
Traditionally, advances in robotic technology have been in the manufacturing industry due to the need for collaborative robots. However, this is not the case in the service sectors, especially in the healthcare sector. The lack of emphasis put on the healthcare sector has led to new opportunities in developing service robots that aid patients with illnesses, cognition challenges and disabilities. Furthermore, the COVID-19 pandemic has acted as a catalyst for the development of service robots in the healthcare sector in an attempt to overcome the difficulties and hardships caused by this virus. The use of service robots are advantageous as they not only prevent the spread of infection, and reduce human error but they also allow front-line staff to reduce direct contact, focusing their attention on higher priority tasks and creating separation from direct exposure to infection. This paper presents a review of various types of robotic technologies and their uses in the healthcare sector. The reviewed technologies are a collaboration between academia and the healthcare industry, demonstrating the research and testing needed in the creation of service robots before they can be deployed in real-world applications and use cases. We focus on how robots can provide benefits to patients, healthcare workers, customers, and organisations during the COVID-19 pandemic. Furthermore, we investigate the emerging focal issues of effective cleaning, logistics of patients and supplies, reduction of human errors, and remote monitoring of patients to increase system capacity, efficiency, resource equality in hospitals, and related healthcare environments. Full article
(This article belongs to the Section Medical Robotics and Service Robotics)
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13 pages, 1513 KiB  
Article
Deep Reinforcement Learning for the Control of Robotic Manipulation: A Focussed Mini-Review
by Rongrong Liu, Florent Nageotte, Philippe Zanne, Michel de Mathelin and Birgitta Dresp-Langley
Robotics 2021, 10(1), 22; https://doi.org/10.3390/robotics10010022 - 24 Jan 2021
Cited by 106 | Viewed by 16669
Abstract
Deep learning has provided new ways of manipulating, processing and analyzing data. It sometimes may achieve results comparable to, or surpassing human expert performance, and has become a source of inspiration in the era of artificial intelligence. Another subfield of machine learning named [...] Read more.
Deep learning has provided new ways of manipulating, processing and analyzing data. It sometimes may achieve results comparable to, or surpassing human expert performance, and has become a source of inspiration in the era of artificial intelligence. Another subfield of machine learning named reinforcement learning, tries to find an optimal behavior strategy through interactions with the environment. Combining deep learning and reinforcement learning permits resolving critical issues relative to the dimensionality and scalability of data in tasks with sparse reward signals, such as robotic manipulation and control tasks, that neither method permits resolving when applied on its own. In this paper, we present recent significant progress of deep reinforcement learning algorithms, which try to tackle the problems for the application in the domain of robotic manipulation control, such as sample efficiency and generalization. Despite these continuous improvements, currently, the challenges of learning robust and versatile manipulation skills for robots with deep reinforcement learning are still far from being resolved for real-world applications. Full article
(This article belongs to the Special Issue Robotics: Intelligent Control Theory)
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22 pages, 7813 KiB  
Article
An Architecture for Safe Child–Robot Interactions in Autism Interventions
by Ilias A. Katsanis and Vassilis C. Moulianitis
Robotics 2021, 10(1), 20; https://doi.org/10.3390/robotics10010020 - 21 Jan 2021
Cited by 8 | Viewed by 6083
Abstract
Autism Spectrum Disorder is a developmental disorder that affects children from a very young age and is characterized by persistent deficits in social, communicational, and behavioral abilities. Since there is no cure for autism, domain experts focus on aiding these children through specific [...] Read more.
Autism Spectrum Disorder is a developmental disorder that affects children from a very young age and is characterized by persistent deficits in social, communicational, and behavioral abilities. Since there is no cure for autism, domain experts focus on aiding these children through specific intervention plans that are aimed towards the development of the deficient areas. Using socially assistive robots that interact in a social manner with children in autism interventions, efforts are being made towards alleviating the autistic behavior of children and enhancing their social behavior. However, implementing robots in autism interventions could lead to harmful situations concerning safety. In this paper, an architecture for safe child–robot interactions in autism interventions is proposed. First, a taxonomy of child–robot interactions in autism interventions is presented, explaining its complete framework. Next, the interaction is modelled according to this taxonomy where an interaction case is employed in order for the structure of the interaction to be defined. Based on that, the safety architecture is proposed that will be integrated into the robot’s controller. Focus is placed on detecting possible distracting elements that could influence the performance of the child, affecting their psychological or physical safety. Lastly, the interaction between child and robot is created in a simulated environment through dialogue inputs and outputs, and the code of the architecture is tested, where a virtual robot performs the appropriate actions. Full article
(This article belongs to the Special Issue Advances in European Robotics)
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23 pages, 4993 KiB  
Review
Localization and Mapping for Robots in Agriculture and Forestry: A Survey
by André Silva Aguiar, Filipe Neves dos Santos, José Boaventura Cunha, Héber Sobreira and Armando Jorge Sousa
Robotics 2020, 9(4), 97; https://doi.org/10.3390/robotics9040097 - 21 Nov 2020
Cited by 89 | Viewed by 12011
Abstract
Research and development of autonomous mobile robotic solutions that can perform several active agricultural tasks (pruning, harvesting, mowing) have been growing. Robots are now used for a variety of tasks such as planting, harvesting, environmental monitoring, supply of water and nutrients, and others. [...] Read more.
Research and development of autonomous mobile robotic solutions that can perform several active agricultural tasks (pruning, harvesting, mowing) have been growing. Robots are now used for a variety of tasks such as planting, harvesting, environmental monitoring, supply of water and nutrients, and others. To do so, robots need to be able to perform online localization and, if desired, mapping. The most used approach for localization in agricultural applications is based in standalone Global Navigation Satellite System-based systems. However, in many agricultural and forest environments, satellite signals are unavailable or inaccurate, which leads to the need of advanced solutions independent from these signals. Approaches like simultaneous localization and mapping and visual odometry are the most promising solutions to increase localization reliability and availability. This work leads to the main conclusion that, few methods can achieve simultaneously the desired goals of scalability, availability, and accuracy, due to the challenges imposed by these harsh environments. In the near future, novel contributions to this field are expected that will help one to achieve the desired goals, with the development of more advanced techniques, based on 3D localization, and semantic and topological mapping. In this context, this work proposes an analysis of the current state-of-the-art of localization and mapping approaches in agriculture and forest environments. Additionally, an overview about the available datasets to develop and test these approaches is performed. Finally, a critical analysis of this research field is done, with the characterization of the literature using a variety of metrics. Full article
(This article belongs to the Special Issue Advances in Agriculture and Forest Robotics)
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19 pages, 23753 KiB  
Article
Simulation of an Autonomous Mobile Robot for LiDAR-Based In-Field Phenotyping and Navigation
by Jawad Iqbal, Rui Xu, Shangpeng Sun and Changying Li
Robotics 2020, 9(2), 46; https://doi.org/10.3390/robotics9020046 - 21 Jun 2020
Cited by 71 | Viewed by 20725
Abstract
The agriculture industry is in need of substantially increasing crop yield to meet growing global demand. Selective breeding programs can accelerate crop improvement but collecting phenotyping data is time- and labor-intensive because of the size of the research fields and the frequency of [...] Read more.
The agriculture industry is in need of substantially increasing crop yield to meet growing global demand. Selective breeding programs can accelerate crop improvement but collecting phenotyping data is time- and labor-intensive because of the size of the research fields and the frequency of the work required. Automation could be a promising tool to address this phenotyping bottleneck. This paper presents a Robotic Operating System (ROS)-based mobile field robot that simultaneously navigates through occluded crop rows and performs various phenotyping tasks, such as measuring plant volume and canopy height using a 2D LiDAR in a nodding configuration. The efficacy of the proposed 2D LiDAR configuration for phenotyping is assessed in a high-fidelity simulated agricultural environment in the Gazebo simulator with an ROS-based control framework and compared with standard LiDAR configurations used in agriculture. Using the proposed nodding LiDAR configuration, a strategy for navigation through occluded crop rows is presented. The proposed LiDAR configuration achieved an estimation error of 6.6% and 4% for plot volume and canopy height, respectively, which was comparable to the commonly used LiDAR configurations. The hybrid strategy with GPS waypoint following and LiDAR-based navigation was used to navigate the robot through an agricultural crop field successfully with an root mean squared error of 0.0778 m which was 0.2% of the total traveled distance. The presented robot simulation framework in ROS and optimized LiDAR configuration helped to expedite the development of the agricultural robots, which ultimately will aid in overcoming the phenotyping bottleneck. Full article
(This article belongs to the Section Agricultural and Field Robotics)
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12 pages, 2679 KiB  
Article
Collection and Analysis of Human Upper Limbs Motion Features for Collaborative Robotic Applications
by Elisa Digo, Mattia Antonelli, Valerio Cornagliotto, Stefano Pastorelli and Laura Gastaldi
Robotics 2020, 9(2), 33; https://doi.org/10.3390/robotics9020033 - 11 May 2020
Cited by 20 | Viewed by 4627
Abstract
(1) Background: The technologies of Industry 4.0 are increasingly promoting an operation of human motion prediction for improvement of the collaboration between workers and robots. The purposes of this study were to fuse the spatial and inertial data of human upper limbs for [...] Read more.
(1) Background: The technologies of Industry 4.0 are increasingly promoting an operation of human motion prediction for improvement of the collaboration between workers and robots. The purposes of this study were to fuse the spatial and inertial data of human upper limbs for typical industrial pick and place movements and to analyze the collected features from the future perspective of collaborative robotic applications and human motion prediction algorithms. (2) Methods: Inertial Measurement Units and a stereophotogrammetric system were adopted to track the upper body motion of 10 healthy young subjects performing pick and place operations at three different heights. From the obtained database, 10 features were selected and used to distinguish among pick and place gestures at different heights. Classification performances were evaluated by estimating confusion matrices and F1-scores. (3) Results: Values on matrices diagonals were definitely greater than those in other positions. Furthermore, F1-scores were very high in most cases. (4) Conclusions: Upper arm longitudinal acceleration and markers coordinates of wrists and elbows could be considered representative features of pick and place gestures at different heights, and they are consequently suitable for the definition of a human motion prediction algorithm to be adopted in effective collaborative robotics industrial applications. Full article
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16 pages, 1368 KiB  
Article
A Pressing Attachment Approach for a Wall-Climbing Robot Utilizing Passive Suction Cups
by Dingxin Ge, Yongchen Tang, Shugen Ma, Takahiro Matsuno and Chao Ren
Robotics 2020, 9(2), 26; https://doi.org/10.3390/robotics9020026 - 13 Apr 2020
Cited by 27 | Viewed by 8255
Abstract
This paper proposes a pressing method for wall-climbing robots to prevent them from falling. In order to realize the method, the properties of the utilized suction cup are studied experimentally. Then based on the results, a guide rail is designed to distribute the [...] Read more.
This paper proposes a pressing method for wall-climbing robots to prevent them from falling. In order to realize the method, the properties of the utilized suction cup are studied experimentally. Then based on the results, a guide rail is designed to distribute the attached suction cup force and implement the pressing method. A prototype of a wall-climbing robot that utilizes passive suction cups and one motor is used to demonstrate the proposed method. An experimental test-bed is designed to measure the force changes of the suction cup when the robot climbs upwards. The experimental results validate that the suction cup can completely attach to the surface by the proposed method, and demonstrate that the robot can climb upwards without falling. Full article
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35 pages, 3632 KiB  
Review
A Review on Design of Upper Limb Exoskeletons
by Muhammad Ahsan Gull, Shaoping Bai and Thomas Bak
Robotics 2020, 9(1), 16; https://doi.org/10.3390/robotics9010016 - 17 Mar 2020
Cited by 280 | Viewed by 37244
Abstract
Exoskeleton robotics has ushered in a new era of modern neuromuscular rehabilitation engineering and assistive technology research. The technology promises to improve the upper-limb functionalities required for performing activities of daily living. The exoskeleton technology is evolving quickly but still needs interdisciplinary research [...] Read more.
Exoskeleton robotics has ushered in a new era of modern neuromuscular rehabilitation engineering and assistive technology research. The technology promises to improve the upper-limb functionalities required for performing activities of daily living. The exoskeleton technology is evolving quickly but still needs interdisciplinary research to solve technical challenges, e.g., kinematic compatibility and development of effective human–robot interaction. In this paper, the recent development in upper-limb exoskeletons is reviewed. The key challenges involved in the development of assistive exoskeletons are highlighted by comparing available solutions. This paper provides a general classification, comparisons, and overview of the mechatronic designs of upper-limb exoskeletons. In addition, a brief overview of the control modalities for upper-limb exoskeletons is also presented in this paper. A discussion on the future directions of research is included. Full article
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16 pages, 9384 KiB  
Article
Design of a UGV Powered by Solar Energy for Precision Agriculture
by Giuseppe Quaglia, Carmen Visconte, Leonardo Sabatino Scimmi, Matteo Melchiorre, Paride Cavallone and Stefano Pastorelli
Robotics 2020, 9(1), 13; https://doi.org/10.3390/robotics9010013 - 13 Mar 2020
Cited by 43 | Viewed by 12826
Abstract
In this paper, a novel UGV (unmanned ground vehicle) for precision agriculture, named “Agri.q,” is presented. The Agri.q has a multiple degrees of freedom positioning mechanism and it is equipped with a robotic arm and vision sensors, which allow to challenge irregular terrains [...] Read more.
In this paper, a novel UGV (unmanned ground vehicle) for precision agriculture, named “Agri.q,” is presented. The Agri.q has a multiple degrees of freedom positioning mechanism and it is equipped with a robotic arm and vision sensors, which allow to challenge irregular terrains and to perform precision field operations with perception. In particular, the integration of a 7 DOFs (degrees of freedom) manipulator and a mobile frame results in a reconfigurable workspace, which opens to samples collection and inspection in non-structured environments. Moreover, Agri.q mounts an orientable landing platform for drones which is made of solar panels, enabling multi-robot strategies and solar power storage, with a view to sustainable energy. In fact, the device will assume a central role in a more complex automated system for agriculture, that includes the use of UAV (unmanned aerial vehicle) and UGV for coordinated field monitoring and servicing. The electronics of the device is also discussed, since Agri.q should be ready to send-receive data to move autonomously or to be remotely controlled by means of dedicated processing units and transmitter-receiver modules. This paper collects all these elements and shows the advances of the previous works, describing the design process of the mechatronic system and showing the realization phase, whose outcome is the physical prototype. Full article
(This article belongs to the Special Issue Advances in Robotics and Mechatronics)
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14 pages, 1707 KiB  
Review
A Review of the Literature on the Lower-Mobility Parallel Manipulators of 3-UPU or 3-URU Type
by Raffaele Di Gregorio
Robotics 2020, 9(1), 5; https://doi.org/10.3390/robotics9010005 - 13 Jan 2020
Cited by 22 | Viewed by 6685
Abstract
Various 3-UPU architectures feature two rigid bodies connected to one another through three kinematic chains (limbs) of universal–prismatic–universal (UPU) type. They were first proposed in the last decade of the 20th century and have animated discussions among researchers for more-or-less two decades. Such [...] Read more.
Various 3-UPU architectures feature two rigid bodies connected to one another through three kinematic chains (limbs) of universal–prismatic–universal (UPU) type. They were first proposed in the last decade of the 20th century and have animated discussions among researchers for more-or-less two decades. Such discussions brought to light many features of lower-mobility parallel manipulators (PMs) that were unknown until then. The discussions also showed that such architectures may be sized into translational PMs, parallel wrists, or even reconfigurable (metamorphic) PMs. Even though commercial robots with these architectures have not yet been built, the interest in them remains. Consequently, a review of the literature on these architectures, highlighting their contribution to the progress of lower-mobility PM design, is still of interest for the scientific community. This paper aims at presenting a critical review of the results that have been obtained up until now. Full article
(This article belongs to the Special Issue Kinematics and Robot Design II, KaRD2019)
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25 pages, 3078 KiB  
Review
Human–Robot Collaboration in Manufacturing Applications: A Review
by Eloise Matheson, Riccardo Minto, Emanuele G. G. Zampieri, Maurizio Faccio and Giulio Rosati
Robotics 2019, 8(4), 100; https://doi.org/10.3390/robotics8040100 - 6 Dec 2019
Cited by 400 | Viewed by 43268
Abstract
This paper provides an overview of collaborative robotics towards manufacturing applications. Over the last decade, the market has seen the introduction of a new category of robots—collaborative robots (or “cobots”)—designed to physically interact with humans in a shared environment, without the typical barriers [...] Read more.
This paper provides an overview of collaborative robotics towards manufacturing applications. Over the last decade, the market has seen the introduction of a new category of robots—collaborative robots (or “cobots”)—designed to physically interact with humans in a shared environment, without the typical barriers or protective cages used in traditional robotics systems. Their potential is undisputed, especially regarding their flexible ability to make simple, quick, and cheap layout changes; however, it is necessary to have adequate knowledge of their correct uses and characteristics to obtain the advantages of this form of robotics, which can be a barrier for industry uptake. The paper starts with an introduction of human–robot collaboration, presenting the related standards and modes of operation. An extensive literature review of works published in this area is undertaken, with particular attention to the main industrial cases of application. The paper concludes with an analysis of the future trends in human–robot collaboration as determined by the authors. Full article
(This article belongs to the Special Issue Advances in Italian Robotics)
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21 pages, 2462 KiB  
Article
Nonlinear Model Predictive Control for Mobile Robot Using Varying-Parameter Convergent Differential Neural Network
by Yingbai Hu, Hang Su, Longbin Zhang, Shu Miao, Guang Chen and Alois Knoll
Robotics 2019, 8(3), 64; https://doi.org/10.3390/robotics8030064 - 31 Jul 2019
Cited by 27 | Viewed by 9839
Abstract
The mobile robot kinematic model is a nonlinear affine system, which is constrained by velocity and acceleration limits. Therefore, the traditional control methods may not solve the tracking problem because of the physical constraint. In this paper, we present the nonlinear model predictive [...] Read more.
The mobile robot kinematic model is a nonlinear affine system, which is constrained by velocity and acceleration limits. Therefore, the traditional control methods may not solve the tracking problem because of the physical constraint. In this paper, we present the nonlinear model predictive control (NMPC) algorithm to track the desired trajectory based on neural-dynamic optimization. In the proposed algorithm, the NMPC scheme utilizes a new neural network named the varying-parameter convergent differential neural network (VPCDNN) which is a Hopfifield-neural network structure with respect to the differential equation theory to solve the quadratic programming (QP) problem. The new network structure converges to the global optimal solution and it is more efficient than traditional numerical methods. In the simulation, we verify that the proposed method is able to successfully track reference trajectories with a two-wheel mobile robot. The experimental validation has been conducted in simulation and the results show that the proposed method is able to precisely track the trajectory maintaining a high robustness based on the VPCDNN solver. Full article
(This article belongs to the Special Issue Robotics and Automation Engineering)
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24 pages, 2687 KiB  
Article
Vision-Based Assisted Tele-Operation of a Dual-Arm Hydraulically Actuated Robot for Pipe Cutting and Grasping in Nuclear Environments
by Manuel Bandala, Craig West, Stephen Monk, Allahyar Montazeri and C. James Taylor
Robotics 2019, 8(2), 42; https://doi.org/10.3390/robotics8020042 - 4 Jun 2019
Cited by 43 | Viewed by 11593
Abstract
This article investigates visual servoing for a hydraulically actuated dual-arm robot, in which the user selects the object of interest from an on-screen image, whilst the computer control system implements via feedback control the required position and orientation of the manipulators. To improve [...] Read more.
This article investigates visual servoing for a hydraulically actuated dual-arm robot, in which the user selects the object of interest from an on-screen image, whilst the computer control system implements via feedback control the required position and orientation of the manipulators. To improve on the current joystick direct tele-operation commonly used as standard in the nuclear industry, which is slow and requires extensive operator training, the proposed assisted tele-operation makes use of a single camera mounted on the robot. Focusing on pipe cutting as an example, the new system ensures that one manipulator automatically grasps the user-selected pipe, and appropriately positions the second for a cutting operation. Initial laboratory testing (using a plastic pipe) shows the efficacy of the approach for positioning the manipulators, and suggests that for both experienced and inexperienced users, the task is completed significantly faster than via tele-operation. Full article
(This article belongs to the Special Issue Robotics in Extreme Environments)
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14 pages, 14306 KiB  
Article
Extending the Application of an Assistant Personal Robot as a Walk-Helper Tool
by Jordi Palacín, Eduard Clotet, Dani Martínez, David Martínez and Javier Moreno
Robotics 2019, 8(2), 27; https://doi.org/10.3390/robotics8020027 - 10 Apr 2019
Cited by 24 | Viewed by 6520
Abstract
This paper presents the application of a mobile robot designed as an Assistant Personal Robot (APR) as a walk-helper tool. The hypothesis is that the height and weight of this mobile robot can be used also to provide a dynamic physical support and [...] Read more.
This paper presents the application of a mobile robot designed as an Assistant Personal Robot (APR) as a walk-helper tool. The hypothesis is that the height and weight of this mobile robot can be used also to provide a dynamic physical support and guidance to people while they walk. This functionality is presented as a soft walking aid at home but not as a substitute of an assistive cane or a walker device, which may withstand higher weights and provide better stability during a walking. The APR operates as a walk-helper tool by providing user interaction using the original arms of the mobile robot and by using the onboard sensors of the mobile robot in order to avoid obstacles and guide the walking through free areas. The results of the experiments conducted with the walk-helper have showed the automatic generation of smooth walking trajectories and a reduction in the number of manual trajectory corrections required to complete a walking displacement. Full article
(This article belongs to the Special Issue Recent Advances on Physical Agents)
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15 pages, 7652 KiB  
Article
V2SOM: A Novel Safety Mechanism Dedicated to a Cobot’s Rotary Joints
by Younsse Ayoubi, Med Amine Laribi, Said Zeghloul and Marc Arsicault
Robotics 2019, 8(1), 18; https://doi.org/10.3390/robotics8010018 - 6 Mar 2019
Cited by 10 | Viewed by 6772
Abstract
Unlike “classical” industrial robots, collaborative robots, known as cobots, implement a compliant behavior. Cobots ensure a safe force control in a physical interaction scenario within unknown environments. In this paper, we propose to make serial robots intrinsically compliant to guarantee safe physical human–robot [...] Read more.
Unlike “classical” industrial robots, collaborative robots, known as cobots, implement a compliant behavior. Cobots ensure a safe force control in a physical interaction scenario within unknown environments. In this paper, we propose to make serial robots intrinsically compliant to guarantee safe physical human–robot interaction (pHRI), via our novel designed device called V2SOM, which stands for Variable Stiffness Safety-Oriented Mechanism. As its name indicates, V2SOM aims at making physical human–robot interaction safe, thanks to its two basic functioning modes—high stiffness mode and low stiffness mode. The first mode is employed for normal operational routines. In contrast, the low stiffness mode is suitable for the safe absorption of any potential blunt shock with a human. The transition between the two modes is continuous to maintain a good control of the V2SOM-based cobot in the case of a fast collision. V2SOM presents a high inertia decoupling capacity which is a necessary condition for safe pHRI without compromising the robot’s dynamic performances. Two safety criteria of pHRI were considered for performance evaluations, namely, the impact force (ImpF) criterion and the head injury criterion (HIC) for, respectively, the external and internal damage evaluation during blunt shocks. Full article
(This article belongs to the Special Issue Mechanism Design for Robotics)
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14 pages, 528 KiB  
Article
Trajectory Design for Energy Savings in Redundant Robotic Cells
by Paolo Boscariol and Dario Richiedei
Robotics 2019, 8(1), 15; https://doi.org/10.3390/robotics8010015 - 20 Feb 2019
Cited by 15 | Viewed by 6935
Abstract
This work explores the possibility of exploiting kinematic redundancy as a tool to enhance the energetic performance of a robotic cell. The test case under consideration comprises a three-degree-of-freedom Selective Compliance Assembly Robot Arm (SCARA) robot and an additional linear unit that is [...] Read more.
This work explores the possibility of exploiting kinematic redundancy as a tool to enhance the energetic performance of a robotic cell. The test case under consideration comprises a three-degree-of-freedom Selective Compliance Assembly Robot Arm (SCARA) robot and an additional linear unit that is used to move the workpiece during a pick and place operation. The trajectory design is based on a spline interpolation of a sequence of via-points: The corresponding motion of the joints is used to evaluate, through the use of an inverse dynamic model, the actuators effort and the associated power consumption by the robot and by the linear unit. Numerical results confirm that the suggested method can improve both the execution time and the overall energetic efficiency of the cell. Full article
(This article belongs to the Special Issue Mechanism Design for Robotics)
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16 pages, 13321 KiB  
Article
Non-Photorealistic Rendering Techniques for Artistic Robotic Painting
by Lorenzo Scalera, Stefano Seriani, Alessandro Gasparetto and Paolo Gallina
Robotics 2019, 8(1), 10; https://doi.org/10.3390/robotics8010010 - 11 Feb 2019
Cited by 30 | Viewed by 10587
Abstract
In this paper, we present non-photorealistic rendering techniques that are applied together with a painting robot to realize artworks with original styles. Our robotic painting system is called Busker Robot and it has been considered of interest in recent art fairs and international [...] Read more.
In this paper, we present non-photorealistic rendering techniques that are applied together with a painting robot to realize artworks with original styles. Our robotic painting system is called Busker Robot and it has been considered of interest in recent art fairs and international exhibitions. It consists of a six degree-of-freedom collaborative robot and a series of image processing and path planning algorithms. In particular, here, two different rendering techniques are presented and a description of the experimental set-up is carried out. Finally, the experimental results are discussed by analyzing the elements that can account for the aesthetic appreciation of the artworks. Full article
(This article belongs to the Special Issue Mechanism Design for Robotics)
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