Design and fabrication of a flexible three-axial tactile sensor array based on polyimide micromachining

• Published in: Microsystem technologies : sensors, actuators, systems integration actuators, systems integration, 2010-12, Vol.16 (12), p.2029-2035
• Main Authors: Kwon, Hyun-Jun, Choi, Woo-Chang
• Format: Article
• Language: English
• Subjects: Applied sciences; Axial forces; Design; Electronics; Electronics and Microelectronics; Engineering; Exact sciences and technology; Finite element method; Force measurement; Instrumentation; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Mechanical Engineering; Mechanical engineering. Machine design; Mechanical instruments, equipment and techniques; Membranes; Microelectromechanical systems; Microelectronic fabrication (materials and surfaces technology); Micromachining; Micromechanical devices and systems; Nanotechnology; Operational amplifiers; Physics; Polymers; Precision engineering, watch making; Robotics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Sensor arrays; Sensors; Shear forces; Shear strain; Silicon wafers; Strain distribution; Strain gauges; Tactile sensors (robotics); Technical Paper; Thin films
• ISSN: 0946-7076; 1432-1858
• DOI: 10.1007/s00542-010-1125-6

This paper describes the design and fabrication of a flexible three-axial tactile sensor array using advanced polyimide micromachining technologies. The tactile sensor array is comprised of sixteen micro force sensors and it measures 13 mm × 18 mm. Each micro force sensor has a square membrane and four strain gauges, and its force capacity is 0.6 N in the three-axial directions. The optimal positions of the strain gauges are determined by the strain distribution obtained form finite element analysis (FEA). The normal and shear forces are detected by combining responses from four thin-film metal strain gauges embedded in a polyimide membrane. In order to acquire force signals from individual micro force sensors, we fabricated a PCB based on a multiplexer, operational amplifier and microprocessor with CAN network function. The sensor array is tested from the evaluation system with a three-component load cell. The developed sensor array can be applied in robots’ fingertips, as well as to other electronic applications with three-axial force measurement and flexibility keyword requirements.