Net-Structure Proximity Sensor: High-Speed and Free-Form Sensor With Analog Computing Circuit

This paper proposes a proximity sensing system, which has advantages of wide sensing area and rapid response. For the rapid and safe behavior of robots, high-speed detection of nearby and noncontact objects is important because of shorter time-to-contact. Here, we propose net-structure proximity sensor (NSPS), which covers large sensing area and fulfills 1-ms response time. NSPS is an array of infrared reflective proximity sensor elements integrated by a resistor network circuitry. Executing analog computation on the electrical circuitry, the sensing system outputs a few of meaningful signals, from the reaction distribution of all the elements. The signals mean the center position and approximate distance to the object. This sensor requires only six external wires regardless of the number of detecting elements. In this paper, we first show that various sizes of NSPS are easily configured by only using standard electronic parts. Next, we prototype NSPS with 25 elements in 5 x 5 matrix, and verify the output characteristics by experiments. At last, we discuss the availability of NSPS for robot hand systems and human-machine interface systems.