Design and Control of Electrical Machines

A special issue of Machines (ISSN 2075-1702). This special issue belongs to the section "Electrical Machines and Drives".

Deadline for manuscript submissions: closed (31 March 2022) | Viewed by 48205

Special Issue Editors


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Guest Editor
Department of Mechanical Engineering, National Taiwan University, Taipei 10617, Taiwan
Interests: robust control;vibration control; system integration; medical engineering;energy systems
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Guest Editor
Department of Intelligent Automation Engineering, National Taipei University of Technology, Taipei 10608, Taiwan
Interests: MEMS; CMOS-MEMS smart sensors; bio-medical and magnetic sensors; bio-mechatronics; IOTs; artificial intelligence in engineering; medical applications
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Graduate Institute of Automation & Control, National Taiwan University of Science and Technology, Taipei 106335, Taiwan
Interests: intelligent control systems;signal and image processing; embedded systems with applications

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Guest Editor
Department of Mechanical Engineering, National Taiwan University, Taipei 10617, Taiwan
Interests: piezoelectric energy harvesting; vibration and dynamics; mechatronics; vehicle dynamics
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Electrical machines play an important role in modern industry. Novel design and advanced control strategies have contributed to the performance improvements of electrical machines and their applications, such as motors, electric vehicles, and power devices. New techniques have also emerged for the control of electrical machines, including artificial intelligence, wireless sensor networks, internet of things, and big data analysis. This Special Issue focuses on the advances related to electrical machines, such as novel designs; novel control strategies; and new technologies including WSNs, IoT, artificial intelligence, new applications, etc. Papers related to electrical machines in this field are most welcome. Topics of interest for publication include, but are not limited to:

  • Novel design of electrical machines.
  • New system architectures and technologies.
  • Electric vehicles, including land, sea, and air vehicles.
  • Applications of electrical machines.
  • Modelling and control of electrical machines and systems.
  • Power devices and systems.
  • Advanced control and optimization algorithms for electrical power systems.
  • Application of WSNs, IoT, and artificial intelligence in electrical machines and systems.

Prof. Dr. Fu-Cheng Wang
Prof. Dr. Chih-Cheng Lu
Prof. Dr. Sendren Sheng-Dong Xu
Prof. Dr. Wei-Jiun Su
Guest Editors

Manuscript Submission Information

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Keywords

  • electrical machines and systems
  • novel design
  • advanced control
  • wireless sensor network
  • internet of things
  • artificial intelligence
  • electric vehicles
  • power devices
  • power systems
  • applications

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Published Papers (15 papers)

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Research

22 pages, 11134 KiB  
Article
Object Tracking for an Autonomous Unmanned Surface Vehicle
by Min-Fan Ricky Lee and Chin-Yi Lin
Machines 2022, 10(5), 378; https://doi.org/10.3390/machines10050378 - 16 May 2022
Cited by 8 | Viewed by 4189
Abstract
The conventional algorithm used for target recognition and tracking suffers from the uncertainties of the environment, robot/sensors and object, such as variations in illumination and viewpoint, occlusion and seasonal change, etc. This paper proposes a deep-learning based surveillance and reconnaissance system for unmanned [...] Read more.
The conventional algorithm used for target recognition and tracking suffers from the uncertainties of the environment, robot/sensors and object, such as variations in illumination and viewpoint, occlusion and seasonal change, etc. This paper proposes a deep-learning based surveillance and reconnaissance system for unmanned surface vehicles by adopting the Siamese network as the main neural network architecture to achieve target tracking. It aims to detect and track suspicious targets. The proposed system perceives the surrounding environment and avoids obstacles while tracking. The proposed system is evaluated with accuracy, precision, recall, P-R curve, and F1 score. The empirical results showed a robust target tracking for the unmanned surface vehicles. The proposed approach contributes to the intelligent management and control required by today’s ships, and also provides a new tracking network architecture for the unmanned surface vehicles. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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34 pages, 14025 KiB  
Article
COVID-19 Pandemic Response Robot
by Min-Fan Ricky Lee and Yi-Ching Christine Chen
Machines 2022, 10(5), 351; https://doi.org/10.3390/machines10050351 - 9 May 2022
Cited by 2 | Viewed by 2064
Abstract
Due to an arising COVID-19 positive confirmed case in Taiwan, the screening of body temperature, mask wearing and quarantined violation is enhanced. A mobile robot that conducts this task is demanded to reduce the human labor. However, conventional robots suffer from several limitations, [...] Read more.
Due to an arising COVID-19 positive confirmed case in Taiwan, the screening of body temperature, mask wearing and quarantined violation is enhanced. A mobile robot that conducts this task is demanded to reduce the human labor. However, conventional robots suffer from several limitations, perceptual aliasing (e.g., different places/objects can appear identical), occlusion (e.g., place/object appearance changes between visits), different viewpoints, the scale of objects, low mobility, less functionality, and some environmental limitations. As for the thermal imager, it displays the current heat spectrum colors, and needs manual monitoring. This paper proposes applying Simultaneous Localization and Mapping in an unknown environment and using deep learning for detection of temperature, mask wearing, and human face on the Raspberry Pi to overcome these problems. It also uses the A* algorithm to do path planning and obstacle avoidance via 3D Light Detection and Ranging to make the robot move more smoothly. Evaluating and implementing different Simultaneous Localization and Mapping algorithms and deep learning models, then selecting the most suitable method. Root Mean Square Error of three Simultaneous Localization and Mapping algorithms are compared. The predictions of deep learning models are evaluated via the metrics (model speed, accuracy, complexity, precision, recall, precision–recall curve, F1 score). In conclusion, Google Cartographer for building a map, Convolutional Neural Network for mask wearing detection, and only looking once for human face detection achieve the best result among all algorithms. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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15 pages, 4055 KiB  
Article
Combined Propulsion and Levitation Control for Maglev/Hyperloop Systems Utilizing Asymmetric Double-Sided Linear Induction Motors
by Vladimir Kuptsov, Poria Fajri, Md. Rasheduzzaman, Salvador Magdaleno-Adame and Konstantin Hadziristic
Machines 2022, 10(2), 131; https://doi.org/10.3390/machines10020131 - 11 Feb 2022
Cited by 3 | Viewed by 3654
Abstract
This article presents a new method for combined levitation and propulsion control in maglev/Hyperloop systems by selectively applying AC and DC modes of operation to a group of asymmetric double-sided linear induction motors (ADSLIMs). Although adjusting the AC current magnitude of lower and [...] Read more.
This article presents a new method for combined levitation and propulsion control in maglev/Hyperloop systems by selectively applying AC and DC modes of operation to a group of asymmetric double-sided linear induction motors (ADSLIMs). Although adjusting the AC current magnitude of lower and upper primary windings in ADSLIMs allows simultaneous control of thrust and lift forces, the limitation of this current balancing technique prohibits them from producing a high lift force while operating with low thrust force. To overcome this limitation and to simultaneously control the thrust and lift forces of the ADSLIMs with high efficiency under different operating conditions, a combination of AC and DC modes of operation is proposed. AC mode of operation consists of feeding different AC current amplitudes to the upper and lower ADSLIM primary windings to produce and control the required thrust and lift forces. The DC mode of operation consists of controlling one or several ADSLIMs to operate with DC excitation to realize the desired lift force at lower thrusts which otherwise cannot be achieved by operating in AC mode alone. The concept of the new combined control strategy is studied using two-dimensional finite element (FE) electromagnetic simulations and compared with an Inductrack permanent magnet (PM) based passive magnetic levitation system. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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17 pages, 7014 KiB  
Article
Commutation Torque Reduction Strategy of Brushless DC Motor Based on Single-Input Dual-Output Cuk Converter
by Xinmin Li, Jingxin Deng, Wei Chen, Lihong Yu and Xuefeng Jin
Machines 2022, 10(2), 117; https://doi.org/10.3390/machines10020117 - 6 Feb 2022
Cited by 3 | Viewed by 1785
Abstract
Based on the Single-Input Dual-Output (SIDO) Cuk converter, a novel commutation torque ripple suppression strategy is proposed for a brushless DC motor (BLDCM). Two voltage scalars are constructed, according to the operating principle of SIDO Cuk converter and BLDCM, and applied to the [...] Read more.
Based on the Single-Input Dual-Output (SIDO) Cuk converter, a novel commutation torque ripple suppression strategy is proposed for a brushless DC motor (BLDCM). Two voltage scalars are constructed, according to the operating principle of SIDO Cuk converter and BLDCM, and applied to the non-commutation and commutation periods, respectively, of BLDCM; the commutation torque ripple in the full speed range is effectively reduced, and this occurs without the need to switch the control strategy according to the speed range. The inverter in the proposed strategy is controlled by the pulse amplitude modulation (PAM) during both non-commutation and commutation periods, and the voltage spike damage caused by the inverter chopping to the motor can be minimized. In addition, the multiple outputs of the SIDO Cuk converter improve the utilization of the DC power for the BLDCM control system. The experimental results verify the effectiveness of the proposed strategy. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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23 pages, 6038 KiB  
Article
Fault-Tolerant Multilevel Converter to Feed a Switched Reluctance Machine
by Vítor Fernão Pires, Armando Cordeiro, Daniel Foito and Armando J. Pires
Machines 2022, 10(1), 35; https://doi.org/10.3390/machines10010035 - 4 Jan 2022
Cited by 12 | Viewed by 2075
Abstract
The switched reluctance machine (SRM) is one of the most interesting machines, being adopted for many applications. However, this machine requires a power electronic converter that usually is the most fragile element of the system. Thus, in order to ensure high reliability for [...] Read more.
The switched reluctance machine (SRM) is one of the most interesting machines, being adopted for many applications. However, this machine requires a power electronic converter that usually is the most fragile element of the system. Thus, in order to ensure high reliability for this system, it is fundamental to design a power electronic converter with fault-tolerant capability. In this context, a new solution is proposed to give this capability to the system. This converter was designed with the purpose to ensure fault-tolerant capability to two types of switch faults, namely open- and short-circuit. Moreover, apart from this feature, the proposed topology is characterized by a multilevel operation that allows improvement of the performance of the SRM, taking into consideration a wide speed range. Although the proposed solution is presented for an 8/6 SRM, it can be used for other configurations. The operation of the proposed topology will be described for the two modes, fault-tolerant and normal operation. Another aspect that is addressed in this paper is the proposal of fault detection and diagnosis method for this fault-tolerant inverter. It was specifically developed for a multilevel SRM drive. The theoretical assumptions will be verified through two different types of tests, firstly by simulation and secondly by experiments with a laboratory prototype. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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14 pages, 6355 KiB  
Article
Torque Ripple Reduction of Switched Reluctance Motor with Non-Uniform Air-Gap and a Rotor Hole
by Grace Firsta Lukman and Jin-Woo Ahn
Machines 2021, 9(12), 348; https://doi.org/10.3390/machines9120348 - 9 Dec 2021
Cited by 14 | Viewed by 4971
Abstract
A switched reluctance motor has a very simple structure which becomes its key signature and leads to various advantages. However, because of its double saliency and switching principle, the motor is also known to have a relatively high torque ripple, and this hinders [...] Read more.
A switched reluctance motor has a very simple structure which becomes its key signature and leads to various advantages. However, because of its double saliency and switching principle, the motor is also known to have a relatively high torque ripple, and this hinders its use as a high-performance drive. In this paper, a method to reduce torque ripple while maintaining average torque is introduced. Two elements are used to achieve this, namely, a non-uniform air-gap on the rotor-pole face and one hole in each non-uniform region, which maintains the saturation level of the air-gap. This approach preserves the mechanical simplicity of the motor and is easy to implement. Simulations and experiments were performed to verify the effectiveness of the proposed design. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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19 pages, 2721 KiB  
Article
PMSM Speed Control Based on Particle Swarm Optimization and Deep Deterministic Policy Gradient under Load Disturbance
by Chiao-Sheng Wang, Chen-Wei Conan Guo, Der-Min Tsay and Jau-Woei Perng
Machines 2021, 9(12), 343; https://doi.org/10.3390/machines9120343 - 8 Dec 2021
Cited by 15 | Viewed by 3816
Abstract
Proportional integral-based particle swarm optimization (PSO) and deep deterministic policy gradient (DDPG) algorithms are applied to a permanent-magnet synchronous motor to track speed control. The proposed methods, based on notebooks, can deal with time delay challenges, imprecise mathematical models, and unknown disturbance loads. [...] Read more.
Proportional integral-based particle swarm optimization (PSO) and deep deterministic policy gradient (DDPG) algorithms are applied to a permanent-magnet synchronous motor to track speed control. The proposed methods, based on notebooks, can deal with time delay challenges, imprecise mathematical models, and unknown disturbance loads. First, a system identification method is used to obtain an approximate model of the motor. The load and speed estimation equations can be determined using the model. By adding the estimation equations, the PSO algorithm can determine the sub-optimized parameters of the proportional-integral controller using the predicted speed response; however, the computational time and consistency challenges of the PSO algorithm are extremely dependent on the number of particles and iterations. Hence, an online-learning method, DDPG, combined with the PSO algorithm is proposed to improve the speed control performance. Finally, the proposed methods are implemented on a real platform, and the experimental results are presented and discussed. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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18 pages, 787 KiB  
Article
Design and Comparison of Reinforcement-Learning-Based Time-Varying PID Controllers with Gain-Scheduled Actions
by Yi-Liang Yeh and Po-Kai Yang
Machines 2021, 9(12), 319; https://doi.org/10.3390/machines9120319 - 26 Nov 2021
Cited by 8 | Viewed by 3332
Abstract
This paper presents innovative reinforcement learning methods for automatically tuning the parameters of a proportional integral derivative controller. Conventionally, the high dimension of the Q-table is a primary drawback when implementing a reinforcement learning algorithm. To overcome the obstacle, the idea underlying the [...] Read more.
This paper presents innovative reinforcement learning methods for automatically tuning the parameters of a proportional integral derivative controller. Conventionally, the high dimension of the Q-table is a primary drawback when implementing a reinforcement learning algorithm. To overcome the obstacle, the idea underlying the n-armed bandit problem is used in this paper. Moreover, gain-scheduled actions are presented to tune the algorithms to improve the overall system behavior; therefore, the proposed controllers fulfill the multiple performance requirements. An experiment was conducted for the piezo-actuated stage to illustrate the effectiveness of the proposed control designs relative to competing algorithms. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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20 pages, 24804 KiB  
Article
Drawing System with Dobot Magician Manipulator Based on Image Processing
by Pu-Sheng Tsai, Ter-Feng Wu, Jen-Yang Chen and Fu-Hsing Lee
Machines 2021, 9(12), 302; https://doi.org/10.3390/machines9120302 - 23 Nov 2021
Cited by 4 | Viewed by 4680
Abstract
In this paper, the robot arm Dobot Magician and the Raspberry Pi development platform were used to integrate image processing and robot-arm drawing. For this system, the Python language built into Raspberry Pi was used as the working platform, and the real-time image [...] Read more.
In this paper, the robot arm Dobot Magician and the Raspberry Pi development platform were used to integrate image processing and robot-arm drawing. For this system, the Python language built into Raspberry Pi was used as the working platform, and the real-time image stream collected by the camera was used to determine the contour pixel coordinates of image objects. We then performed gray-scale processing, image binarization, and edge detection. This paper proposes an edge-point sequential arrangement method, which arranges the edge pixel coordinates of each object in an orderly manner and places them in a set. Orderly arrangement means that the pixels in the set are arranged counterclockwise to the closed curve of the object shape. This arrangement simplifies the complexity of subsequent image processing and calculation of the drawing path. The number of closed curves represents the number of strokes in the drawing of the manipulator. In order to reduce the complexity of the drawing of the manipulator, a fewer number of closed curves will be necessary. To achieve this goal, we not only propose the 8-NN (abbreviation for eight-nearest-neighbor) search, but also use to the 16-NN search and the 24-NN search methods. Drawing path points are then converted into drawing coordinates for the Dobot Magician through the Raspberry Pi platform. The structural design of the Dobot reduces the complexity of the experiment, and its attitude and positioning control can be accurately carried out through the built-in API function or the underlying communication protocol, which is more suitable for drawing applications than other fixed-point manipulators. Experimental results show that the 24-NN search method can effectively reduce the number of closed curves and the number of strokes drawn by the manipulator. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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12 pages, 5238 KiB  
Communication
On the Asymptotic Behavior and Parameter Estimation of a Double-Sided LCC-Compensated Wireless Power Transfer System
by Feng-Rung Hu and Jia-Sheng Hu
Machines 2021, 9(11), 287; https://doi.org/10.3390/machines9110287 - 13 Nov 2021
Cited by 4 | Viewed by 1967
Abstract
This study investigates the statistic behavior and parameter estimation problems of a double-sided, LCC-compensated, wireless power transfer system. Based on the commonly used wireless charging circuit model, this study proposes a five-step parameter estimation method, which is applicable to automotive static wireless charging [...] Read more.
This study investigates the statistic behavior and parameter estimation problems of a double-sided, LCC-compensated, wireless power transfer system. Based on the commonly used wireless charging circuit model, this study proposes a five-step parameter estimation method, which is applicable to automotive static wireless charging systems. The eight parameters in the circuit model of this study are the most important key components of the wireless charging system. The study also found that, under certain conditions, the statistic mode of wireless charging systems has a specific distribution. However, the current status of these eight components for wireless charging of electric vehicles will have complex parameter drift problems. These drift problems will deteriorate the performance of the vehicle power systems. This study probes these factors and proposes some related mathematical theories. The noted factors can be applied to the analysis of the wireless charging system and provide alternative solutions to explain the deteriorations from coil misalignments. Both simulations and experiments are given to show the evaluated issues of the proposed study. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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21 pages, 46545 KiB  
Article
An Inductive Active Filtering Method for Low-Voltage Distribution Networks
by Delu Li, Xiao Zhang, Xianming Deng and Changyi Li
Machines 2021, 9(11), 258; https://doi.org/10.3390/machines9110258 - 29 Oct 2021
Cited by 2 | Viewed by 2047
Abstract
Three-phase unbalanced and nonlinear loads aggravate harmonic problems in low-voltage distribution networks. In this paper, a hybrid inductive and active filter (HIAF) system with a Ddy converter transformer is proposed. By establishing the circuit and corresponding mathematical models, the working mechanism of the [...] Read more.
Three-phase unbalanced and nonlinear loads aggravate harmonic problems in low-voltage distribution networks. In this paper, a hybrid inductive and active filter (HIAF) system with a Ddy converter transformer is proposed. By establishing the circuit and corresponding mathematical models, the working mechanism of the HIAF system in harmonic suppression is analyzed. In the designed HIAF system, we install the detection point on the grid-side winding and the compensation point on the filtering winding. Since both windings have the same connection, no phase compensation between the harmonic detection point and compensation point is demanded. Eventually, we apply a harmonic damping control and zero-value impedance control strategy to realize harmonic suppression under both balanced and unbalanced loads. The simulation results show that the HIAF system can effectively suppress harmonics under various load conditions. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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16 pages, 4570 KiB  
Article
Modular Segmented Motor for Power-Assist Wheelchairs: Proof of Concept
by Ilya A. Galkin, Rahims Geidarovs and Andrejs Podgornovs
Machines 2021, 9(10), 227; https://doi.org/10.3390/machines9100227 - 6 Oct 2021
Cited by 4 | Viewed by 2171
Abstract
This paper presents an analysis of the opportunity to increase the price availability of small electric vehicles, such as electric scooters, such as bicycles and wheelchairs, by applying expandability and modularity principles to their motors. Assuming that, in many cases, small electric vehicles [...] Read more.
This paper presents an analysis of the opportunity to increase the price availability of small electric vehicles, such as electric scooters, such as bicycles and wheelchairs, by applying expandability and modularity principles to their motors. Assuming that, in many cases, small electric vehicles are brought to the market in several power/price versions, the authors of this report evaluate the possibility of combining different numbers of electromechanical modules while, at the same time, maintaining the unity of the entire drive/motor scheme, thus making the mentioned expandability possible. Power-assist wheelchairs are taken as an example of the application, where such expandability is reasonable. The application provides a price reduction for the less powerful wheelchairs in the case of less severe disabilities. To start, the authors briefly compare multidrive schemes that ground the principle of modularity at the electromechanical level. Then, they outline a radially segmented motor concept and discuss this concept using the example of a permanent magnet synchronous motor. In particular, they propose a methodology for the calculation of its parameters and calculate the particular design details of such a motor. The motor is then analyzed with the help of its mathematical model, as well as experimentally. This tentative evaluation of two 50 W segments (of a 300 W 6-segment motor) proves that the proposed segmented modularity concept is feasible, and that it requires a more detailed consideration of the parameters and the other implementation aspects (power driver, control, cooling) of the given synchronous motor. Moreover, the concept might be successfully utilized in the designs of other motor types. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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21 pages, 9451 KiB  
Article
Decoupled Multi-Loop Robust Control for a Walk-Assistance Robot Employing a Two-Wheeled Inverted Pendulum
by Fu-Cheng Wang, Yu-Hong Chen, Zih-Jia Wang, Chi-Hao Liu, Pei-Chun Lin and Jia-Yush Yen
Machines 2021, 9(10), 205; https://doi.org/10.3390/machines9100205 - 22 Sep 2021
Cited by 2 | Viewed by 2972
Abstract
This paper develops a decoupled multi-loop control for a two-wheeled inverted pendulum (TWIP) robot that can assist user’s with walking. The TWIP robot is equipped with two wheels driven by electrical motors. We derive the system’s transfer function and design a robust loop-shaping [...] Read more.
This paper develops a decoupled multi-loop control for a two-wheeled inverted pendulum (TWIP) robot that can assist user’s with walking. The TWIP robot is equipped with two wheels driven by electrical motors. We derive the system’s transfer function and design a robust loop-shaping controller to balance the system. The simulation and experimental results show that the TWIP system can be balanced but might experience velocity drifts because its balancing point is affected by model variations and disturbances. Therefore, we propose a multi-loop control layout consisting of a velocity loop and a position loop for the TWIP robot. The velocity loop can adjust the balancing point in real-time and regulate the forward velocity, while the position loop can achieve position tracking. For walking assistance, we design a decoupled control structure that transfers the linear and rotational motions of the robot to the commands of two parallel motors. We implement the designed controllers for simulation and experiments and show that the TWIP system employing the proposed decoupled multi-loop control can provide satisfactory responses when assisting with walking. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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13 pages, 3898 KiB  
Communication
Improved Haptic Transparency of Bilateral Control Using Torque-Measured Magnetic Coupling
by Trieu-Khang Tu, I-Haur Tsai, Jia-Yush Yen, Tsu-Chin Tsao and Mi-Ching Tsai
Machines 2021, 9(8), 172; https://doi.org/10.3390/machines9080172 - 18 Aug 2021
Cited by 1 | Viewed by 2264
Abstract
The integrity and transparency of a haptic feedback in a bilateral control is crucial for precise and accurate operators’ sensation during human–machine interactions. Conventional master and slave bilateral control systems are often subject to unknown or unwanted disturbances and dynamics in the actuators [...] Read more.
The integrity and transparency of a haptic feedback in a bilateral control is crucial for precise and accurate operators’ sensation during human–machine interactions. Conventional master and slave bilateral control systems are often subject to unknown or unwanted disturbances and dynamics in the actuators and powertrain linkages that hamper the haptic feedback integrity and transparency. Force sensor torque sensing and feedback control are required to mitigate these effects. In contrast to the conventional approach of introducing torque sensing using a mechanical spring, this paper introduces a magnetic coupling as a torque sensor to detect reaction torque between the human input and the master actuator. Disturbance observer-based torque feedback control is designed to suppress the disturbances and tailor the haptic transparency dynamics. Experimental results on a virtual reality interaction system, which involves the steering wheel bilateral control in a cyber-physical driving simulator system, demonstrate the feasibility and effectiveness of the proposed method with improved haptic integrity and transparency. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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18 pages, 7700 KiB  
Article
Iterative Parameter Optimization for Multiple Switching Control Applied to a Precision Stage for Microfabrication
by Fu-Cheng Wang, Jun-Fu Lu, Tien-Tung Chung and Jia-Yush Yen
Machines 2021, 9(8), 153; https://doi.org/10.3390/machines9080153 - 3 Aug 2021
Viewed by 1953
Abstract
This paper proposes an iteration procedure to derive optimal parameters for a multiple switching control architecture. Control design is usually a compromise between various performance requirements; therefore, switching between multiple controllers that achieve a particular performance under different conditions can potentially improve the [...] Read more.
This paper proposes an iteration procedure to derive optimal parameters for a multiple switching control architecture. Control design is usually a compromise between various performance requirements; therefore, switching between multiple controllers that achieve a particular performance under different conditions can potentially improve the overall system behavior. In this paper, we consider a control-switching mechanism that can automatically switch controllers based on the prediction of future responses, and we develop an iteration procedure that can optimize the mechanism parameters, such as the number of controllers and the prediction horizon. We then implement the proposed mechanism in a long-stroke precision stage, and demonstrate the effectiveness of switching robust control with simulations and experiments. Lastly, we integrate the stage with a two-photon polymerization system to fabricate microlenses. The optical properties confirm that the proposed iterative parameter optimization procedure is effective in improving the performance of microfabrication employing multiple switching control. Full article
(This article belongs to the Special Issue Design and Control of Electrical Machines)
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