Accurate remote measurement of robot trajectory motion

The development, calibration and evalution of a two camera opto-electronics remote measuring system is described. The measuring system, developed by the National Bureau of Standards (NBS), precisely tracks in three dimensions the location of infrared emitting LEDs. An approach being developed by NBS will use the system for accurately measuring robot trajectory motion and position within a calibrated work volume. This paper evaluates the performance of the measurement system apart from any specific applications. The measuring system, which uses two tetra-lateral photodiode cameras, has a resolution of approximately 0.01 percent and an absolute accuracy of 0.05 percent along each of the three dimensions of a work volume when using data points from within the center 80 percent of the detector field of view. Accuracy degrades to 0.1 percent when including data points from outside the center 90 percent of the field of view. Data collection rate is 3.3 kHz for one data point (LED) location measurment. Implementation and analysis procedures are also discussed.