Tactic to Improve Detecting Accuracy on Robotic System with Structural Installation Error

Robotic arms of roll-pitch structure equipped with position detector on the terminal joint to detect certain target need extreme accurate attitude. A still coordinate system is often chosen as a base coordinate system. Accurate joint angular detection through joint angular sensors and precise installation of position detector on the terminal joint contribute to precise target position on the base-coordinate system. A series of coordinate transformation is essential to compute target position base on above angular parameters. However, some installation errors usually exist in the robotic arms and extra theoretical analysis must be taken into consideration. Corresponding compensation process can eliminate the errors and accurate position information leads to precise target position. Installation errors from position detector in terminal joint and angle sensors in joints of robotic arm are analyzed. Pertinent compensation methods are designed for those errors. This paper compares target position detected directly from terminal detector and joint angle detectors with position after compensation and validates the effectiveness of the method.