压阻式触觉传感器对法向力和剪切力的检测

Detection of normal and shear force with piezoresistive tactile sensor

灵活的触觉传感器应该具有像皮肤一样的功能,能够检测施加力的大小和方向。改进的压阻式触觉传感器,主要由中心芯和4个侧壁组成,法向力和剪切力的感测元件不同。将压阻式触觉传感器嵌入到一个聚二甲基硅氧烷(PDMS)弹性体中,以实现力的柔性检测。通过仿真分析,得到此种触觉传感器对法向力的检测范围为600 Pa^65 k Pa,可测得的最小剪切力为900 Pa。通过进一步分析,得到施加法向力和剪切力时法向力感测元件阻值的变化曲线,可得此种触觉传感器能够有效降低法向力感测元件与剪切力感测元件之间的干扰。所开发的触觉传感器可以灵活检测施加的法向力和剪切力,可应用于机器人手臂和假肢上。

Flexible tactile sensors should have the same function as the skin,which can detect magnitude and direction of the applied force. The improved piezoresistive tactile sensor is made up of a central core and four side walls,and sensing elements for normal force and shear force are different. The tactile sensor is embedded in a polydimethylsiloxane（ PDMS） elastomer,to realize flexible detection. Through simulation analysis,detection range of normal force of tactile sensor is 600 Pa~ 65 k Pa,and the minimum shear force is 900 Pa. By further analysis,resistance change curve of normal force sensing element when the normal force and shear force are applied on the sensor is obtained. The tactile sensor can effectively reduce the interference between the normal force sensing element and shear force sensing element. The developed tactile sensor can flexibly detect the applied normal force and shear force,it can be used in robot arm and prosthesis.