Motion planning for robotic arms integrated on mobile platforms for internal logistics tasks

Abstract

The developed work in this dissertation is part of the MIAR project, which focuses on using synchronized Mobile Intelligent Autonomous Robots (MIAR) to automate logistics operations at Bosch Car Multimedia BrgP. The autonomous mobile manipulator must perform pick-and-place operations involving Targets, boxes containing certain electronic products, between a storage buffer and access ramps connected to the assembly lines. The purpose of this dissertation was to develop motion planning for the KUKA LBR iiwa 14 R820 manipulator to execute the intended tasks. The use of a redundant arm in this project aimed to create collision-free trajectories in confined spaces. Firstly, a simulation model was created at CoppeliaSim to represent the Bosch shop floor where the mobile manipulator will operate. Under this scenario, several tasks were performed, such as determining the number of boxes the manipulator could handle from the dollies and checking the maximum number of boxes that could be transported on top of the mobile platform. To carry out the planning tests, the collaborative gripper 2FGP20 was selected to meet the project’s requirements, and custom-designed fingers were simulated at Autodesk Fusion to withstand the imposed loads during manipulation. Additionally, new optimized ramps were introduced to ensure that the arm could access boxes. A method of communication between CoppeliaSim and MoveIt, software used for trajectory generation, was implemented. This communication was established using ROS2 via two launch files. A benchmarking study was conducted among ten planners, identifying T-RRT as the most suitable for the project. Subsequently, the planner was customized to ensure better results across diverse manipulation scenarios, and a post-processor was utilized to verify if it would lead to significant improvements, considering the project's stringent requirements. In conclusion, the manipulator demonstrated satisfactory performance, given the complexity of its working environment. Some limitations were identified, and suggestions for future improvements were proposed. Keywords: Global Planners, Motion Planning, Pick-and-Place, Smoothness