Colorectal Cancer is the third most common cancer globally, while colonoscopy is the gold standard for early screening, which is instrumental in improving patient outcomes. However, conventional colonoscopes cause pain and discomfort to the patient, thus reducing the uptake of colorectal cancer screening. Besides, mastering the use of conventional colonoscopes requires extensive clinical training. Although surgical robotics offers countless advantages in a range of minimally invasive procedures, robotic-assisted colonoscopy remains an open research field due to the specific challenges associated with bowel anatomy.

This thesis presents the design, control, and experimental evaluation of a teleoperation system for minimally invasive surgery in colonoscopy.
The proposed system consists of a master controller and a soft robotic slave manipulator.
The master controller includes a novel mechanism with a passive decoupling mechanism and an orientation locking mechanism designed for misalignment compensation during clutching.
The experimental results indicate that both mechanisms can effectively compensate for misalignment.
The soft robotic manipulator employs pneumatic actuation and consists of three soft actuated segments connected in series resulting in six degrees of freedom at the tip. A sequential fabrication process that is applicable to similar soft manipulators is also outlined. In addition, a soft sensing skin is developed to measure the shape of the soft robotic manipulator in a proprioceptive fashion. Thanks to a unique design based on an inextensible tube that limits the axial extension of the soft manipulator, the system was shown to provide sufficient bending angle and force output for a range of minimally invasive surgery tasks.
Experimental results indicate that the manipulator is characterized by nonlinear stiffness and hysteresis, which should be accounted for in the kineto-static model. To this end, an optimization method is employed to calibrate the kinematic model parameters, resulting in improved accuracy. A position control strategy that includes an integral action to compensate for the effects of model uncertainties is proposed. Finally, the master controller and the soft robotic manipulator are integrated into a master-slave proof-of-concept intended for teleoperated colonoscopy. The effectiveness of the proposed system is demonstrated with experiments in a laboratory setup.