This paper proposes and demonstrates a novel flexible tactile sensor for both normal and shear load detections. For the realization of the sensor, polyimide and polydimethylsiloxane are used as a substrate, which makes it flexible. Thin metal strain gauges, which are incorporated into the polymer, are used for measuring normal and shear loads. The salient feature of this tactile sensor is that it has no diaphragm-like structures. The unit tactile cell characteristics are evaluated against normal and shear loads. The fabricated tactile sensor can measure normal loads of up to 4 N, and the sensor output signals are saturated against loads of more than 4 N. Shear loads can be detected by different voltage drops in strain gauges. The device has no fragile structures; therefore, it can be used as a ground reaction force (GRF) sensor for balance control in humanoid robots. Four tactile unit sensors are assembled and placed in the four corners of the robot's sole. By increasing bump dimensions, the tactile unit sensor can measure loads of up to 2 kgf. When loads are exerted on the sole, the GRF can be measured by these four sensors. The measured forces can be used in the balance control of biped locomotion systems.
Bibliographical noteFunding Information:
Manuscript received June 15, 2006; revised February 11, 2007. This work was supported in part by the Ministry of Information and Communication, Korea, under the Information Technology Research Center support program that is supervised by the Institute of Information Technology Assessment (IITA) under Grant IITA-2005-C1090-0502-0012, and in part by the Korea Science and Engineering Foundation through the National Core Research Center for Nanomedical Technology under Grant R15-2004-024-00000-0. Subject Editor C. Liu.
All Science Journal Classification (ASJC) codes
- Mechanical Engineering
- Electrical and Electronic Engineering