Sensing elasticity from the phase difference of the stepper motor

We have developed a made-to-order surgical support manipulator with a function that senses the mechanical characteristics of internal organs, and which can be customized based on the maximum grasping force of the patient. The purpose of this study is to establish an elasticity-sensing model that uses the phase difference of the stepper motor based on material strength and to apply it to in vitro organs. In this study, we propose a measurement model and develop a prototype that is used in experiments on silicon rubber and in vitro organs in a dog. Young´s modulus E and spring constant K are measured by the prototype and a material testing machine. The results of the prototype showed good agreement with those of the material testing machine, and that the proposed model will be a great help in the development of surgical support manipulators.