A Pneumatic Force Sensor for Enhanced Force Feedback in Robotic Colonoscopy

Colonoscopy is often associated with significant discomfort, which can be mitigated by incorporating haptic feedback into robotic systems. This paper presents the design and experimental evaluation of a force sensing system integrated with haptic feedback for robotic colonoscopy. The system utilizes pneumatic sensing pouches mounted on the tip of a robotic colonoscope to capture contact forces in real-time and provide feedback to the operator via a haptic joystick. The pouch sensor demonstrates accuracy, with a maximum RMS error of 0.2 N during rigid phantom testing, while achieving 85% phase classification accuracy in detecting on-load and off-load states. Haptic force feedback significantly reduces peak interaction forces, lowering the maximum contact force from 1 N to 0.6 N without compromising task duration. Experiments in a soft colon phantom confirm the system’s ability to detect forces in anatomically representative environments, demonstrating its potential for clinical use.