Reactive Planning MPC of Pusher-Sliders with Obstacle Avoidance and Imposed Velocity Profiles

• Published in: International Conference on Control, Decision and Information Technologies (Online) pp. 1469 - 1474
• Main Authors: De Witte, Sander, Neve, Thomas, Lefebvre, Tom, Crevecoeur, Guillaume
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.07.2024
• Subjects: Dynamics; Heuristic algorithms; Manipulator dynamics; Optimization; Planning; Prediction algorithms; Predictive control; Real-time systems; Robot sensing systems; Trajectory
• ISSN: 2576-3555
• DOI: 10.1109/CoDIT62066.2024.10708389

Non-prehensile manipulation aims to change how robots handle objects, going beyond conventional grasping, including pushing, sliding, tipping, rolling, and throwing. These manipulation modes however face new challenges in sensing, planning and control. This motivates the development of advanced and dedicated algorithms. This research explores the use of Model Predictive Control to control the motion of objects through pushing and sliding on a practical pusher-slider system. We develop a reactive path planning feedback controller that can navigate dynamic objects in real-time. To that end, we introduce a simplified model with advantageous properties. Differential flatness allows the description of dynamically feasible trajectories in a representation not subject to differential constraints, simplifying motion optimization. A temporal invariance property of the state trajectories allows us to simplify the problem further into a strictly geometric optimization where velocities are imposed in a second stage. We show that the method is sufficiently computationally efficient to support reactive replanning when facing dynamic obstacles. Experimental validation with a KUKA manipulator and vision-based tracking demonstrates the applicability of this method.