A lightweight robot for motion planning in industrial settings

Abstract

Kinematically redundant industrial robot has been used extensively in the industry due to its flexibility, dexterity and productivity. Yet, the complexity of motion planning for the robot remains a major hurdle preventing small and median enterprises (SMEs) from enjoying its benefits. This is brought about by motor redundancy and motion repeatability issues. Two main methods are developed in the industry, which actively specify each join’s motion. The teaching pendant method is tedious and is highly reliant on the skill level of the operator, whereas the software in software programming method remains unaffordable to most SMEs. This project addresses the aforementioned issues with the visco-elastic Passive Motion Paradigm (PMP) framework. Joint motions in the robot are produced in a passive, unique and non-repeatable manner, upon dragging the robot end effector to reach an intended goal. To implement the visco-elastic PMP framework in a mechanical device, linear elastic bands are used at the joints, such that the stiffness and the equilibrium configuration of the joints can be modulated by the number and the position of the elastic bands respectively. In this report, the mechanical design specifications for a lightweight motion planning robot are formulated. Different stages of the design are demonstrated, from proof of concept models to different versions of the design. A physical model is built according to the final design of the motion planner. Troubleshooting of the model is carried out, including design analysis, modification and friction characterization. At the end of the project, conclusion and future work are presented.