Motion Planning of a Robotic Manipulator for 3D Scanning of Moving Objects on a Conveyor.

Abstract

Industrial automation requires the automatic robots to p����form material handling, assembly operations, and quality inspection mainly while achieving better performance in precision, accuracy and production rate of the continuous operation. Objects moving on a conveyor need to inspect quality in latter application where the robot should identify the object orientation and position to track the object. Then the robot is required to follow the object while maintaining no relative speed, and the absolute maximum speed specified for effective scanning. This research addresses such issues by taking 3D portable scanning as the application. Quanser kinova 6-DoF robot arm is simulated with the conveyor. The speed of the conveyor is maintained at a constant speed and the measured speed is fed to the computer. Proximity sensors placed on the conveyor track the objects so that the robot can start tracking and following the object. Images taken through a low-cost camera detect objects orientation following the proposed technique and adjust its end effector orientation to execute the scanning trajectory. The 3D shape of the object obtained from the manual scanning prior to the operation is sliced perpendicular to the one principle axis. The offset contours of the sliced sections and motion conditions at inflection points of path segments are fed as initial inputs to the algorithm for trajectory generation. Results obtained through the simulation of polynomial trajectories in the Cartesian space are presented. Compared to the existing works, this research demonstrates a complete solution for object tracking, specially focusing the 3D scanning, and addresses several issues to be considered when adjusting the robot dynamics.