Experimental kinematic identification of a 3-DOF decoupled parallel robot using calibrated kinect sensor

Abstract

This paper aims at laying down the state of the art of kinematic identification problem of parallel mechanisms for a 3-DOF fully decoupled parallel robot, the so-called “Tripteron”. Due to manufacture errors there are some kinematic uncertainties in the robot which cause real kinematic equations of the robot to be different from the theoretical ones. In this paper, using a white box identification procedure, the independence of degrees-of-freedom in the robot is studied. Considering the fact that the kinematic identification of a robotic manipulator requires the position of its end-effector to be known, in this paper, a so-called “Kinect” sensor which is a vision-infra red sensor is utilized to obtain the spatial coordinates of the end-effector. In order to calibrate the Kinect a novel approach which is based on a neuro-fuzzy algorithm, the so-called “LoLiMoT” algorithm, is used. The results of experimentally performing the identification and calibrating approach are reported in the paper.