Array sensor for tactile sensing in robotic applications

Capacitance transducers have been designed and constructed for position measurement. They possess properties of ruggedness, reliability, freedom from temperature variations and capability of operation in hazardous environments. Configurations designed to overcome two problems associated with capacitance transducers aimed at tactile sensing are discussed. The first one concerns that of electrical connections and the second one that of miniaturisation to obtain a fine pitch. An array of 18×10 elements at 0.2 cm pitch has been built in which the return force is provided by compressed air at the back of the array. The flow of air keeps the pins lubricated but clean as well. It is concluded that although this sensor is capable of portraying 3-D images, tactile sensing is a great deal more than that and attention must be devoted to incorporating force, torque, slip and even temperature measurement