Performance Evaluation and Optimisation of Multi-point Waveguide based optical Sensor for Soft Robots

Soft optical-based waveguide sensors display fast response, drastically low power consumption, and offer an effective means by which to detect deformation in soft actuators a desideratum of soft robot applications. Their sensitivity to non-uniform deformations at high curvature and external stimuli, however, remains an issue in ensuring their robustness and resilience. In previous work, we introduced a soft multi-point optical-based waveguide sensor for bending detection in soft actuators. In this paper, we investigate the effect of certain parameters that contribute directly to the sensitivity of the sensing elements (waveguides). These parameters include: the length of the waveguides, the housing silicone materials, the thickness of the multi-point sensor, the configuration of the sensor, and waveguide dimension and coating. To show the effect of these parameters, compression cyclic tests of 20 cycles were performed and the results evaluated to arrive at an optimum sensor design in terms of parameters trade-offs.