Design and Implementation of Sensor Platform for UAV-Based Target Tracking and Obstacle Avoidance
Round 1
Reviewer 1 Report
The manuscript is well written and well presented, with a good balance between descriptive text and simulation. It starts from a real problem, wants to achieve better flight efficiency and proposes an interesting solution in the management of the sensors necessary for navigation even in VTOL architectures. The manuscript proposes the design aspect and the simulation, however there is a lack of practical tests both in the laboratory and in the operational field. I hope that all of this is a starting point and that I can see these results as soon as possible on next scientific papers.
In the manuscript, pending the experimental part, it would be interesting only a few small insights on the aspects that I cite below.
149 3.3. Platform Implementation Techniques
The main purpose of the project is target tracking and collision avoidance; the proposed design solution can generate vibrations which can be a problem in aerial photography. Are there conditions, assumptions or limits within which this gimbal can also be used in aerial photography? Is further development conceivable in this sense? It would be useful to clarify this aspect.
238 5. Platform Performance Validation Test
It would be interesting to make the simulation parameters more explicit to provide the reader with a better understanding and replication tools.
Have you also included in the simulation weather conditions such as wind that make it more difficult to aim due to continuous perturbations? If yes it would be useful to know under what conditions.
309 6 Results and discussions
A few more words on the type and limitations of sensors applicable to the gimbal (mass, size, etc.) would be useful.
It would be interesting to address the operating limits of the gimbal in relation to the various flight parameters: speed, accelerations, etc. Have you done any simulations for this purpose? Do you have any data on these aspects?
Author Response
149 3.3. Platform Implementation Techniques
The main purpose of the project is target tracking and collision avoidance; the proposed design solution can generate vibrations which can be a problem in aerial photography. Are there conditions, assumptions or limits within which this gimbal can also be used in aerial photography? Is further development conceivable in this sense? It would be useful to clarify this aspect.
Answer: Vibration is indeed a challenge to acquiring quality aerial photography. We will use dampers in joint areas as well as between the platform and the sensors. To reduce vibration during platform steering, we will use brushless motors instead of servo motors. The platform is already manufactured and assembled. After field tests, we will analyze the qualities of aerial photography and discuss on further development of the platform.
238 5. Platform Performance Validation Test
It would be interesting to make the simulation parameters more explicit to provide the reader with a better understanding and replication tools.
Have you also included in the simulation weather conditions such as wind that make it more difficult to aim due to continuous perturbations? If yes it would be useful to know under what conditions.
Answer: We didn’t include wind perturbation effect in this stage. However, your suggestion will help us in further development of platform control algorithm.
309 6 Results and discussions
A few more words on the type and limitations of sensors applicable to the gimbal (mass, size, etc.) would be useful.
Answer: The weights of the sensors are constrained by the payload carrying capability of a UAV whereas their dimensions are limited by the spherical volume made by central-bay and the two canopies. The diameter of the spherical volume is specified in section 3.2. and the dimensions of the components are given in Table 1 of the revised manuscript.
It would be interesting to address the operating limits of the gimbal in relation to the various flight parameters: speed, accelerations, etc. Have you done any simulations for this purpose? Do you have any data on these aspects?
Answer: Thank you for the information. We didn’t do simulation tests on operational limitations with regard to speed and accelerations. As we are currently developing the control algorithm for the platform, we will take your valuable information into consideration.
Reviewer 2 Report
This work studied a sensor platform with simple design but effective steer, which can be applied to UAV for obstacle avoidance and target tracking. The research on this platform is meaningful. However, there are a few flaws :
- The designed sensor platform is installed on the top of the fixed-wing UAV, whilethe existing scheme is installed on the bottom of UAV. Both of the schemes are capable of target tracking, obstacle avoidance and other tasks, is there any difference between both of the schemes? advantages and disadvantages?
- Notice that there isinteraction between the sensor platform and the controller of UAV, what are the details of the stability control and pointing control between them? How to control the sensor platform? An illustrative diagram of the control scheme is suggested.
- There are somewriting mistakes (or compiling mistakes?), such as 'fig??’ in line 28 Please check throughout the manuscript to eliminate such problems.
Author Response
1. The designed sensor platform is installed on the top of the fixed-wing UAV, while the existing scheme is installed on the bottom of UAV. Both of the schemes are capable of target tracking, obstacle avoidance and other tasks, is there any difference between both of the schemes? advantages and disadvantages?
Answer: In the fifth paragraph of section 1, the limitation of belly-mounted gimbals is stated. For reference, the statements are indicated in blue color as shown in the manuscript.
2. Notice that there is interaction between the sensor platform and the controller of UAV, what are the details of the stability control and pointing control between them? How to control the sensor platform? An illustrative diagram of the control scheme is suggested.
Answer: Thank you very much for your valuable suggestion. In section 5.1.1., it is stated that the control of the UAV and the sensor platform is managed through tunable custom parameter. Moreover, we are currently developing platform control algorithm in which we set various conditions to make sure that any manual control of the platform does not affect the UAV control system.
3. There are some writing mistakes (or compiling mistakes?), such as 'fig??’ in line 28 Please check throughout the manuscript to eliminate such problems.
Answer: We made corrections to mistakes in the manuscript.
Reviewer 3 Report
The paper presents and discusses the interesting engineering decision for the specific application of UAV in closely area of the city for the traffic monitoring or other similar problems. The proposed and substantiated sensors’ platform is good decision for this problem. The paper has good presentation and I have not any comment about the result novelty, technical implementation or mathematical foundation. The core of the investigation is well presented. But this this decision should be considered in more wide context. And first of all I’d propose to consider in the paper analysis of possible areas of the drones application and perspectives of proposed decision for the other problem based on drone’s use. As the help authors can use the publications of this analysis:
Smith, M.L.; Smith, L.N.; Hansen, M.F. The quiet revolution in machine vision-a state-of-the-art survey paper, including historical review, perspectives, and future directions. Comput. Ind. 2021, 130, 103472.
Mukhamediev, R.I.; Symagulov, A.; et al. Review of Some Applications of Unmanned Aerial Vehicles Technology in the Resource-Rich Country. Appl. Sci. 2021, 11, 10171. https://doi.org/10.3390/app112110171
Agarwal, A.; Kumar, S.; Singh, D. Development of Neural Network Based Adaptive Change Detection Technique for Land Terrain Monitoring with Satellite and Drone Images. Def. Sci. J. 2019, 69, 47–480
Author Response
The paper presents and discusses the interesting engineering decision for the specific application of UAV in closely area of the city for the traffic monitoring or other similar problems. The proposed and substantiated sensors’ platform is good decision for this problem. The paper has good presentation and I have not any comment about the result novelty, technical implementation or mathematical foundation. The core of the investigation is well presented. But this decision should be considered in more wide context. And first of all I’d propose to consider in the paper analysis of possible areas of the drones application and perspectives of proposed decision for the other problem based on drone’s use. As the help authors can use the publications of this analysis:
Smith, M.L.; Smith, L.N.; Hansen, M.F. The quiet revolution in machine vision-a state-of-the-art survey paper, including historical review, perspectives, and future directions. Comput. Ind. 2021, 130, 103472.
Mukhamediev, R.I.; Symagulov, A.; et al. Review of Some Applications of Unmanned Aerial Vehicles Technology in the Resource-Rich Country. Appl. Sci. 2021, 11, 10171. https://doi.org/10.3390/app112110171
Agarwal, A.; Kumar, S.; Singh, D. Development of Neural Network Based Adaptive Change Detection Technique for Land Terrain Monitoring with Satellite and Drone Images. Def. Sci. J. 2019, 69, 47–480
Answer: Thank you very much for your fruitful review of our work. Following your suggestion, we read the papers and included them as references since they have enlightenment for the readers of our paper. We also included further applications of the proposed sensor platform in the revised manuscript as shown the last paragraph of section 3.3.
Round 2
Reviewer 2 Report
The paper presents a novel sensor platform.There is a good application for UAV to target track and obstacle avoid. After revision, the paper is well presented in investigation of the implementation techniques and the mathematical model of the sensor platform .The paper can be accepted in present form.
