A tactile sensing array with tunable sensing ranges using liquid crystal and carbon nanotubes composites

摘要

This work presents the development of a novel 4 × 4 pressure sensing array with tunable sensing ranges. Carbon nanotubes (CNTs) dispersed in nematic liquid crystals (LC) composite is employed as the resistive sensing material. The structure of the sensing element, in which the LC-CNT composite is sealed, consists of a deformable PDMS elastomeric structure, an indium tin oxide (ITO) glass substrate and an ITO PET film. The force sensing ranges can be tuned by varying frequency of the driving voltage supplied by the array scanning circuitry. This tunable capability can be employed for the applications which require different measurement ranges of forces, without the need of adjusting the dynamic ranges of the sensor readout circuitry. The characteristics of the devices are measured and the pressure images with tunable capability are successfully captured. The driving and scanning circuit for resistive sensing array is also designed and implemented.