Development and control of a magnetorheological haptic device for robot assisted surgery

Abstract

A prototype magnetorheological (MR) fluid-based actuator has been designed for tele-robotic surgical applications. This device is capable of generating forces up to 47 N, with input currents ranging from 0 to 1.5 A. We begin by outlining the physical design of the device, and then discuss a novel nonlinear model of the device's behavior. The model was developed using the Hammerstein-Wiener (H-W) nonlinear black-box technique and is intended to accurately capture the hysteresis behavior of the MR-fluid. Several experiments were conducted on the device to collect estimation and validation datasets to construct the model and assess its performance. Different estimating functions were used to construct the model, and their effectiveness is assessed based on goodness-of-fit and final-prediction-error measurements. A sigmoid network was found to have a goodness-of-fit of 95%. The model estimate was then used to tune a PID controller. Two control schemes were proposed to eliminate the hysteresis behavior present in the MR fluid device. One method uses a traditional force feedback control loop and the other is based on measuring the magnetic field using a Hall-effect sensor embedded within the device. The Hall-effect sensor scheme was found to be superior in terms of cost, simplicity and real-time control performance compared to the force control strategy.

Application of a Nonlinear Hammerstein-Wiener Estimator in the Development and Control of a Magnetorheological Fluid Haptic Device for Robotic Bone Biopsy

“…The experimental methods used in the tissue-forces study were based on ex vivo non-perfused organs. Therefore, these methods have the following limitations: First, the measured forces obtained may have higher values than true force measurements from living tissues because post-mortem tissues stiffen with time [57]. Second, factors such as the geometric properties of the needles and insertion angles may affect insertion forces [58].…”

“…The second study described the development, modeling, and characterization of the FGM as a proof of concept. The final study presented the FGM implemented in a master-slave configuration to control a robotic biopsy procedure and outlines an H-W feedback control strategy used to apply the FGM in a simulated surgical scenario [57].…”

Detection techniques of biological and chemical Hall sensors

“… 113 In addition, Shokrollahi et al built a robot haptic system based on a magnetorheological fluid method for the sensor disposable, cheap and indirect system for pressure measurements. 114 surgery assistance. Hall sensor (TLE4990, Infineon), as a force sensor, was indirectly employed to eliminate device undesirable hysteresis behaviors.…”