Monte-Carlo Simulation Technique for Repeatability Analysis of 3-axis Cartesian Robot using Position Resolution of a Ball Screw

Offline programming will be made for simulating the end-effector motion of a 3-axis Cartesian robot to figure out whether it could be positioned within the bound of peg-in-hole working condition or not. The 3axis Cartesian robot is for handling glass lenses of both digital cameras and cellular phone cameras of which needs are gradually increasing worldwide. The endeffector of robot has a vacuum gripper which can do peg-in-hole simultaneous jobs for 6 non-spherical glass lenses. The repeatability (i.e., 5 ) of an endeffector for peg-in-hole job is of major concern in order to prevent both error motion and interference with 6 cavities This paper aims at estimating the positional accuracy (i.e., repeatability) of a 3-axis Cartesian robot with ball-screw mechanism, in order to verify the design of robot a priori, before the actual assembling of the robot. For this purpose, Monte-Carlo (based) simulation is used for virtually measuring position errors, instead of physical measurement. Based on the positional accuracy (i.e., lead error) of ball screw, the Monte-Carlo simulation technique for repeatability analysis will be proposed.