BMe Research Grant
Time-optimal path tracking is still an active topic in robotic research [H4]. The aim of my work is to extend this research area by creating algorithms that can solve the control problem significantly faster than the existing methods in the literature. My secondary goal is that these algorithms do not tighten the possible constraints of the system, and therefore, they can be considered as a fully usable alternative to the existing approaches.
The presented algorithms are published in highly ranked journals [F1-F5]. We also created several experimental scenarios, where the methods are demonstrated and validated using a robotic manipulator. As a practical example of the path tracking application, we solved the waiter motion problem (see Figure 3). The problem consists of moving a tablet carrying one or more glasses along a prescribed spatial path as fast as possible so that the objects placed on it do not slide. A closely related problem is the pick-and-place task with suction cups, which is used in logistics and other industrial applications.
Another application of the path tracking problem is related to a Japanese robotics company. The company offers vision based solutions for industrial robots, and its products have been installed in many factories. Their solutions can perform object recognition and pose estimation in three dimensions. Based on the presented sequential solver, we developed a custom software for the company, which solves the path tracking problem. The software can cooperate with Robot Operating System (ROS), which is a popular robotic platform. The program can handle various constraints, including end-effector and joint limitations. In Figure 4, an example application can be seen, where the velocity profile is generated using the sequential solver. The software development was performed in the frame of a contract between BME and the company (contract registry number is AUT 2019, 411.175/2019).
[F1] Á. Nagy, G. Csorvási, I. Vajk. “Path Tracking Algorithms for Non-Convex Waiter Motion Problem”. In: Periodica Polytechnica Electrical Engineering and Computer Science 62.1 (2018), pp. 16–23.
[F2] Á. Nagy, I. Vajk. “LP-based velocity profile generation for robotic manipulators”. In: International Journal of Control 91.3 (2018). IF*: 2.101, pp. 582–592.
[F3] Á. Nagy, I. Vajk. “Non-Convex Time-Optimal Trajectory Planning for Robot Manipulators”. In: Journal of Dynamic Systems, Measurement, and Control (2019). IF*: 1.521, in press
[F4] Á. Nagy, I. Vajk. “Sequential Time-Optimal Path Tracking Algorithm for Robots”. In: IEEE Transactions on Robotics (2019). IF*: 4.264. in press
[F5] L. Consolini, M. Locatelli, A. Minari, Á. Nagy, I. Vajk. “Optimal Time Complexity Speed Planning for Robot Manipulators”. In: IEEE Transactions on Robotics 35.3 (2019). IF*: 4.264, pp. 790–797.
[K1] Á. Nagy, I. Vajk. “Validating Time Optimal Path Tracking Algorithm for Robots”. In: Proceedings of the Automation and Applied Computer Science Workshop 2016: AACS’16. 2016, pp. 141–149.
[K2] Á. Nagy, I. Vajk. “Minimum-time path tracking for robots with non-convex constraints”. In: 2017 IEEE 15th International Symposium on Intelligent Systems and Informatics (SISY). 2017, pp. 163–168.
[K3] Á. Nagy, I. Vajk. “Peaked Optimisation Problem for Motion Planning in Robotics”. In: Proceedings of the Automation and Applied Computer Science Workshop 2017: AACS’17. 2017, pp. 147–156.
[K4] G. Csorvási, Á. Nagy, I. Vajk. “Near Time-Optimal Path Tracking Method for Waiter Motion Problem”. In: 20th World Congress of the International Federation of Automatic Control. 2017, pp. 4929–4934.
[H1] Thomas Lipp, Stephen Boyd. “Minimum-time speed optimisation over a fixed path”. In: International Journal of Control 87.6 (2014), pp. 1297–1311.
[H2] B. Siciliano, O. Khatib. “Springer Handbook of Robotics”. Springer-Verlag Berlin Heidelberg, 2008.
[H3] D. Verscheure, B. Demeulenaere, J. Swevers, J. Schutter, M. Diehl. “Time-Optimal Path Tracking for Robots: A Convex Optimization Approach”. In: IEEE Transactions on Automatic Control 54.10 (2009), pp. 2318–2327.
[H4] H. Pham, Q. Pham. “A New Approach to Time-Optimal Path Parameterization Based on Reachability Analysis”. In: IEEE Transactions on Robotics 34.3 (2018), pp. 645–659.
[H5] F. Debrouwere, W. Van Loock, G. Pipeleers, Q. T. Dinh, M. Diehl, J. Schutter, J. Swevers. “Time-Optimal Path Following for Robots with Convex-Concave Constraints Using Sequential Convex Programming”. In: IEEE Transactions on Robotics 29.6 (2013), pp. 1485-1495.
[H6] I. Spasojevic, V. Murali, S. Karaman. “Asymptotic Optimality of a Time Optimal Path Parametrization Algorithm”. Version 1. 2019. arXiv: 1904.04968 [cs.RO]