Characterizing the performance of an optical slip sensor for grip control in a prosthesis

Few commercially available prostheses have integrated force sensors for grip control. This paper introduces an optical-based sensor to detect a grasped object´s displacement. The proposed sensor is commonly used as the sensing component in optical computer mice. The performance of the sensor was tested against objects with various optical properties to get a measure of slip detection accuracy for objects that an amputee may encounter on a daily basis. The sensor was found to accurately detect motion for the majority of the tested surfaces, with the exception of transparent surfaces or those with very high reflectivity. This research may help the development of a controlled prostheses that could assist an amputee in grasping an object for long periods of time without dropping it.