Detection of Dynamic Information for Tactile Sensors Utilizing a Suspension Shell

This paper describes dynamic analysis of a tactile sensor using suspension shell to sense not only normal force but also arbitrary force in direction and position. Notice that the angular displacements of β, γ, α and linear displacements ofρ, λ expressing the behavior of the suspension shell are given, and that the number of external forces contacting the shell is supposed to be one. Then, algebraic formulation is made to determine the magnitude, direction and position of the force uniquely by considering a dynamic equilibrium condition. Only the longitudinal force of the springs suspending the shell coaxially around the rigid finger body is utilized. Lateral force of the spring does not appear since the ends of the springs are connected by ball joints. Thus the dynamic analysis becomes simple. Calculation procedures to extract magnitude, direction and position of the external force are shown. Also, simulation to verify the proposed procedures are made. The suspension shell having similar forms of the finger body is rigid, and thus it gives the sensor robustness.