Calibration algorithm of cam flat-faced follower mechanism

Abstract

In motion control industry, the motion accuracy is one of the main concerns and as the system is more accurate, it will be more expensive and complex. In terms of micrometer, the situation is more complex because most of the manufacturing technologies right now cannot achieve this accuracy and there will be always a dimension tolerance. In this paper, a new calibration method is used to calibrate a Cam Disk with Flat-Faced Follower mechanism to convert rotary motion to linear motion with a low cost and high accuracy approach. The motion system to be calibrated is using stepper motor attached with a cam disk follower mechanism with one digital homing sensor to detect the home angle. Then another linear distance sensor is added for calibration that will be used only once the mechanism is installed for calibration then it can be removed so the mechanism can completely work with high accuracy with the homing sensor only. The system accuracy depends on the accuracy of the homing sensor and the calibration sensor. The calculations to calibrate the mechanism and calculate the mechanism accuracy is using a homing sensor with calibration sensor both with 1 um accuracy. The result is a motion control with an accuracy of less than 5 um with only homing sensor. This method is important to solve the manufacturing tolerance problem and to be able to move accurately without real-time feedbacks with complex and expensive system.