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A model predictive control framework to control hand movements relying on tactile illusions

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Recent studies showed that the sense of touch is able to guide hand movements. When a blindfolded subject slides his/her finger-pad on a ridged plate to reach a target, the contribution of tactile feedback induces the illusory percept of bending towards the direction estimates by tactile cues (i.e., the one perpendicular to the ridges), and this induces a systematic error on hand trajectories in the opposite direction with respect to the one estimated by touch. The goal of this paper is to control the previously explained illusion to guide the user’s finger moving on the ridged plate towards an arbitrary desired point A, while he/she is instructed to move towards an another point B. To this end, we designed a Model Predictive Control strategy, relied on the results of a Kalman filter model, in a simulated environment to estimate at each time instant the optimal ridge orientation. Here, we simulated fifty trials for a particular position of the point A and B. The results show that the final points of the simulated hand trajectories are for the 90% of the cases in a range of ±1.5 ◦ with respect to the angular position of the desired final goal A. These results open promising applications in the framework of haptic retargeting where only one real object is used and the other items of the scene are virtual.