Extension and implementation of performance evaluation indices for impedance control schemes on ARASH:ASiST

Master Thesis Defense

Extension and implementation of performance evaluation indices for impedance control schemes on ARASH:ASiST

The lack of adequate skill is one of the most prevalent causes of surgical errors among novice surgeons during their initial training phases. It is essential to consider an effective approach to transfer the trainers’ expertise and increase their involvement in the training process. As an aid to facilitate surgery training, ARASH:ASiST have been developed to facilitate surgical training with a collaborative dual-user haptic-enabled system. In this system, the expert surgeon (trainer) and the novice surgeon (trainee) collaboratively conduct the surgical tasks through their own haptic devices. In order to describe the objectives and facilitate controller design for dual-user haptic systems, this thesis introduces a responsive variable impedance control structure as a training approach. The main objective of this performance-based varying impedance control structure is to imitate or enhance the hands-on training experience, which is usually provided during the traditional training process. Then, considering the importance of stability in these systems, the stability analysis is presented by considering the closed-loop stability of the nonlinear system. The experimental results are implemented on the ARASH:ASiST haptic device, which is specially designed for vitrectomy surgery. Finally, the evaluation indices are introduced to investigate the effectiveness of the proposed training approach to improve novice surgeons’ performance levels during surgical training. In brief, the main contribution of this thesis is to introduce novel training approaches and develop control schemes based on the training approach. Additionally, the performance of the evaluation indices shows that the proposed training approach is very promising and could be used for further development and clinical experiments.