Localized differential sensing of soft deformable surfaces

There is an increasing interest in the use of soft technologies for robotic application, however, the lack of advanced sensory motor capabilities is currently a significant limitation. Sensing of soft robots, in particular, is still not fully understood and methods by which a large deformable continuum body can be effectively sensed without loosing the intrinsic soft body dynamics are limited. This paper proposes a novel soft body sensing method, localized differential sensing, whereby the sensing of localized deformation on a large soft structure can be achieved with a pair of strain sensors. The design principles for this method are given. To demonstrate this sensing method Conductive Thermoplastic Elastomer (CTPE) is used for the sensing of deformation of soft body structures. A feasibility study of the approach is also presented, with strain sensors incorporated into the universal gripper to allow detection of grasped objects.