This paper presents a tactile sensor capable of measuring Young's modulus and shear modulus of elasticity for polymers, soft tissue, and other materials. The sensor is built by using polydimethylsiloxane as the structural material. A number of sensing cells of different stiffnesses are used in each sensor. The Young's modulus of the targeted object can be measured based on the relative deflections of adjacent sensing cells. The shear modulus measurement is enabled by using a quad-electrode structure in each sensing cell. Experimental results show sensing resolutions of 0.1 MPa for Young's modulus measurement in the range of 0.1-1 MPa and 0.05 MPa for shear modulus measurement ranging from 0.05 to 0.2 MPa. The flexible tactile sensor can be integrated on the end effector of robotic arms to achieve tactile sensing feedback. The proposed sensing technology can also be utilized for fast measurement of both Young's modulus and shear modulus for industrial applications that involve measuring mechanical properties of materials.
Bibliographical noteFunding Information:
Manuscript received February 26, 2011; revised June 21, 2011 and July 24, 2011; accepted September 16, 2011. Date of publication October 18, 2011; date of current version July 2, 2012. This work was supported in part by the Minimally Invasive Medical Technologies Center (http://www.mimtec.org), a National Science Foundation Industry–University Cooperative Research Center.
Sensor fabrication was performed at the Nano Fabrication Center, University of Minnesota, Minneapolis, which is supported by the National Science Foundation’s National Nanotechnology Infrastructure Network.
Copyright 2012 Elsevier B.V., All rights reserved.
- Flexible sensor
- microelectromechanical systems
- polydimethylsiloxane (PDMS)
- shear elasticity
- tactile sensor