An Integrated Optical-Robotic Measurement System

Abstract

This paper presents the results of an experiment designed to test a prototype integrated optical-robotic measurement system that is intended to measure the external profile of arbitrarily shaped cable connectors for subsequent manufacture of a jig to hold the connectors accurately in place during an automated cable-tree assembly and wiring process, see Figure 1. The desired measurement error tolerance is ±0.1 mm. Integrating an industrial robot into the measurement system has the advantage that the measurement procedure can be automated. The main disadvantage is that accuracy, repeatability and calibration issues must be addressed. We have designed the measurement procedure, carried out by the robot, to be less dependent on absolute robot accuracy and instead rely on the lower limits: repeatability and relative accuracy. By matching the degrees-of-freedom (DOF) used by the robot at key stages in the process to the DOF of the measurement task, we remain closer to the lower limits of the robot accuracy.