Psychological and physiological model of tactile rendering fidelity using combined electro and mechanical vibration

High-fidelity tactile rendering offers significant potential for improving the richness and immersion of touchscreen interactions. This study focuses on a quantitative description of tactile rendering fidelity using a custom-designed hybrid electrovibration and mechanical vibration (HEM) device. An electrovibration and mechanical vibration (EMV) algorithm that renders 3D gratings with different physical heights was proposed and shown to achieve 81% accuracy in shape recognition. Models of tactile rendering fidelity were established based on the evaluation of the height discrimination threshold, and the psychophysical-physical relationships between the discrimination and reference heights were well described by a modification of Weber’s law, with correlation coefficients higher than 0.9. The physiological-physical relationship between the pulse firing rate and the physical stimulation voltage was modeled using the Izhikevich spiking model with a logarithmic relationship.