Design and Fabrication of a Low Cost Optical Tactile Sensor

This paper presents the design and fabrication of an optical tactile sensor unit for the measure of the physical human-robot interaction pressure. This sensor consists of an infrared transmitter and an infrared receiver, which is covered by a soft silicone layer in the form of a pyramidal frustum. In this sensor, by applying the force to the sensor, the soft layer is deformed and the curtain within the cover closes the light way between transmitter and receiver. Then, the output voltage of the sensor varies with a proportional relation to the external force. The significant privilege of this optical tactile sensor unit can be regarded as high sensitivity, very low-cost, high reliability, easy to fabricate, very low power consumption. Hence, such a sensor unit can be used in the future for fabrication of a very low-cost smart shoe. The proposed sensor has an accuracy of 0.1N and a range of 9N.