Analysis and design of a robotic distance sensor

Abstract

Abstract Analysis and design of a robotic electrooptical distance sensor, based on the phase‐shift measurement of a modulated light intensity, is addressed in this article. The transducer of this sensor employs two light sources (light‐emitting diodes), whose intensities are modulated by different‐phase sine‐wave signals, and one photodiode receiver. The distance of an object's surface with respect to the sensor is measured by investigating the received phase shift. The experimental set‐up of the sensor, used in this research, was designed and manufactured such that various mechanical and electronic design parameters could be investigated independently. Experiments undertaken show that these parameters indeed affect the performance of the sensor. The exemplary optimization analysis carried out considered only two performance aspects of the sensor, namely, sensitivity and operational range, and yielded corresponding optimal design parameters. The optimal distance sensor analyzed illustrated that it has sufficient resolution to be useful for most existing industrial robots.