Improvement of harmonic dissector for minimal invasive surgery, modeling and the stiffness identification of the clipped object

In this paper, the modeling for the harmonic dissector in minimal invasive surgery (MIS) is proposed. This model is the series connection of a mass-spring-damper system and a nonlinear system. The former is based on the mechanical property of the dissector, and the latter is in the fundamental of the hysteresis description of the piezo-actuator, which is the driving part of the dissector. In addition, based on hysteresis compensation and force control, this paper also proposed a method which can be used to identify the stiffness of the object which is clipped by the dissector. In terms of the stiffness identification, this paper only introduces a theoretical approach. As for the experimental validation, it will be carried out in the future work.