Kinematic accuracy of picking robot constructed by wire-driven continuum structure

Abstract

This paper is to explore the motion accuracy of a novel picking robot constructed by wire-driven continuum structure and liner screw platform. The continuum structure features the hollow configuration, by which the object could be transported along its internal space, such as fruits harvesting. For discussing the precision theoretically and driving the presented robot, the kinematic model and workspace were established, also the instantaneous kinematics based on Jacobian matrix was analyzed. Further, the motion precision with different postures in the workspace were analyzed based on dexterity index by decomposing Jacobian matrix. Finally, as a typical tracking, the circular trajectory are deployed for demonstrating the theoretical modelling through the simulations and experiments in different region of workspace. The results of comparison of experiments and planned trajectories showed that the average error of the end point is about 2.538% with the proposed method by adjust the position of robot into a higher precise region, while without adjusting the robot's position, the average error of the end point reached 4.537%. The proposed method could be extended to a control strategy for rigid-flexible coupled robot.