A flexible, highly-sensitive, and easily-fabricated carbon-nanotubes tactile sensor on polymer substrate

A flexible, highly-sensitive, and easily fabricated carbon nanotubes (CNTs) tactile sensor is reported in this paper. CNTs are grown and patterned on bulk-micromachined silicon substrate with 3-dimensional surface profile. After polymer molding, the CNTs with 3-dimensional distribution are successfully transferred onto a flexible PDMS with 3-dimensional tactile-bump. Advantages of presented tactile sensor are (1) exactly determine loading force by resistance change due to almost linearly current-voltage (I-V) characteristics, (2) embedded patterned CNTs into polymer using simple silicon-substrate molding process, (3) 3-dimensional distributed CNTs enable the detection of shear and normal forces, and (4) 3-dimensional polymer structure by molding as a tactile-bump. One of anisotropic-type patterned CNT approach behaves good sensing sensitivity of both normal (23%/N) and shear (18%/N) forces loading. With proper CNTs designs, tactile sensor has normal and shear forces sensitivities of up to 23%/N and 95%/N, respectively.