Object shape recognition with artificial whiskers using tomographic reconstruction

Existing techniques utilizing bio-inspired robotic whisker sensory systems generally address object feature extraction with artificial whiskers as a mechanical problem. We present an alternative signal-processing approach that formulates the object shape recognition as a 2-D tactile imaging problem. Observing that the whisker position at the very initial contact is similar to a 'ray path' in X-ray computed tomography; the 2-D cross-sectional image of the object can be tomographically reconstructed by measuring only the angle at the whisker base and the whisker-base location at the initial contact for each viewing angle. This approach has the important practical advantage of eliminating the need for the calibration of the force/moment measurements. Experimental results demonstrate the promising potential for bio-inspired systems using arrays of vibrissal sensors for object shape recognition.