A Novel Tactile Sensor for Detecting Lumps in Breast Tissue

We developed a compact tactile sensor in order to guide the clinician or the self-user for non-invasive detection of lumps. The new design has an advantage over the existing discrete tactile sensors and detection methods by efficiently sensing force distribution over an area without any side effects. The sensor consists of 10×10 infrared emitter-detector pairs, a silicon-rubber elastic pad, and a contoured tactile interface (25x21 moving pins) for palpating threedimensional objects. To demonstrate the practical use of the sensor, first a cylindrical tissue-like silicon phantom was prepared, then a 13 mm diameter rigid spherical object was placed at varying depths of 0-20 mm to simulate cancerous lumps in breast tissue, and finally the tactile sensor was systematically pressed on the phantom to successfully detect the lumps for compression depths of 1024 mm. The location and the estimated radius of each lump were calculated from the recorded tactile images.