High resolution pressure sensing using sub-pixel shifts on low resolution load-sensing tiles

In ambient intelligence, pressure sensing can be used for detecting and recognizing objects based on their load profile. This paper presents a pressure scanning technique that improves weight-based object recognition, by adding information about the surface of the object in contact with the floor. The new high-resolution pressure scanning technique employs sub-pixel shifting to assemble a series of low-resolution scans into an aggregated high-resolution scan. The proposed scanning device is composed of 4 load-sensing tiles, on which the scanned object slides in regular movements. The result is a regular grid image of the object´s contact surface, containing the weight of each section of the grid, as well as the corresponding centers of mass. A formal proof-of-concept is provided, together with experimental results obtained both on a noiseless simulated platform, and on a noisy physical platform.