A Haptic Interface with Motor/Brake System for Colonoscopy Simulation

Abstract

Training for colonoscopy, which is the examination and treatment of the colon, is often performed on real patients once the physician has passed the novice level. This increases the risk to the patient and lengthens the procedure time. Since a decade ago, there has been research on virtual reality surgery simulators with haptic feedback. The main goal is to provide an alternative to traditional training methods on animals, cadavers or real patients. Haptic feedback is a key feature for every surgery simulator for the training of hand-eye coordination. In this paper, a compact and portable haptic interface is presented for the colonoscopy. The haptic interface provides position data acquisition and force feedback in linear and rotational directions with combined electrical motors and passive brakes to cover a large range of forces. The motorized drives are used for active force feedback and friction compensation and the brakes are used for high force rendering without slipping. This novel design allows decoupled motion in both directions.

Experimental evaluation of a haptic interface for endoscopic simulation

“…The force bandwidth of the device is around 13 Hz which is sufficient to render forces during a typical colonoscopy procedure. These results satisfy the design requirements summarized in [20] except the maximum torque requirement which is 1 Nm for a procedure performed with an adult size colonoscope [1]. Limitation of 0.3 Nm maximum torque in the rotational DOF is due to the slip between the endoscope and the friction rollers.…”

“…To address the need for higher fidelity and complexity in a colonoscopy simulator, we have designed a new haptic interface [20] and instrumented a clinical colonoscope [17] in order to integrate it with the software simulation framework for colonoscopy (MILX TM GastroSim) developed at CSIRO [12,5]. Several prototypes have been built, presented at medical conferences and commercialization is imminent.…”

Virtual reality for medical training: the state-of-the-art

“…The simulator provides robust simulation of the deformation of the colon, high visual fidelity, and a specially built haptic interface that enables the user to manipulate a real endoscope with tactile feedback (Samur et al, 2008). Their work provides an excellent solution for 'cavity simulators'.…”

Manipulator Design for a Haptic System with Improved Performance

“…A design of an MR-brake based haptic device is introduced in [11] and a multi degree-of-freedom haptic device was built by using an MR-fluid brake [12]. Some researchers even used the MR-brakes with the conventional motor-capstan drive systems [13] to increase the z-width of the device by increasing the maximum stiffness of the system. Figure 6: Design details of the bi-directional MR-brake system [16] A magneto-rheological (MR) fluid based semi-active actuation system or in other words, an MR-fluid based brake system is designed to resolve this problem of displaying larger amount of static forces without jeopardizing the dynamic performance of the system.…”