Enabling feedback position control of an industrial robot based on external sensor signals for dual-stage actuation

This paper presents an advanced control error processing to enable the feedback position control of an industrial robot based on external sensor signals for dual-stage actuation. A measurement module comprising a magnetically levitated platform with an integrated 3D measurement tool is mounted as end effector on the industrial robot. The industrial robot is used to maintain the measurement platform within its limited actuation range, while actively tracking a sample in motion. The measurement module provides the short stroke but precision positioning of the measurement tool relative to a sample surface in 6-DoF. For a feedback controlled repositioning of the industrial robot’s tool center point based on the internal measurement platform’s position signals, a real-time interface is used. The implementation of the advanced control error processing successfully demonstrates the active tracking of a sample in motion, with residual tracking errors of 473 nm rms in sample-motion direction.