Finite Element Analysis of a Flexible Tactile Sensor with Circular Pattern

Additive manufacturing technology presents new opportunities and challenges for tactile sensor fabrication and packaging. Specifically, aerosol jet printing technology enables on-demand deposition of a wide selection of materials onto flexible substrates with potentially uneven surfaces, and feature sizes in the micron scale. One of the applications of aerosol jet printing is integrated tactile sensors onto robotic and mechatronic devices. In this paper, we present a design and simulation study of a new tactile sensor that is compatible with the aerosol jet printing process on customized, flexible printed circuit (FPC) substrates, featuring a strain gauge with a circular pattern. The tactile sensor is packaged in between the cover and bedding - two pieces of elastomer material that give the sensor space to comply and deform. A dimple and a cavity were added to the cover and bedding respectively to help the sensor concentrate external forces onto the location where strain is detected. Finite element analysis (FEA) was conducted to study the performance of the proposed design, with respect to the relative sizes of the dimple and the cavity on the circular sensor pattern. Simulation results show the feasibility of finding the best combination of the dimple and cavity size, which can be used to optimize our sensor design.