Abstract
A haptic position measurement system (HPMS), which utilizes the haptic feedback of a hand-held magnetic sensor to touch and measure the position and shape of soft material and compliant objects, is developed and applied to measure the NiTi precurved guidewire suturing of stomach. A miniature (0.90 mm diameter) magnetic sensor is the touch probe to contact and measure the 0.69 mm thin pre-curved guidewire during insertion to the soft tissue, which is an endoscope-based obesity treatment procedure. The system, which has an accuracy of about 0.3 mm, was applied to measure the geometry of four types of pre-curved guidewire in the ex-vivo stomach wall suturing. Experimental results show that the pre-curved guidewire with a small bevel angle and a small radius of curvature has less change in shape and better suturing accuracy. The HPMS is capable of tracking the guidewire during suturing and measuring the shape for computer-aided surgical path planning.