Beating Heart Motion Compensation Using Active Observers and Disturbance Estimation

Abstract

One important issue that surgeons need to deal during delicate procedures are the physiological motions induced by the breathing and the heartbeat. To avoid the use of external heart-lung machines, which implies in a great risk to the patient and a long recovery time, many research works have been developed in order to design a method able to cancel these motions and give to the surgeon a perception of a stable environment. This paper proposes a new force control scheme using an Active Observer based on the Kelvin Boltzmann interaction model. A feedforward term and a disturbance estimation are included in the control scheme to improve the disturbance estimation. This estimation is performed using the viscoelastic Kelvin Boltzmann tissue model and a quasi-periodic Fourier series model. The results show the ability of the proposed force control scheme to reject beating heart motions. Performance under parameters mismatch is also analyzed.