Design and Evaluation of a Novel Haptic Interface for Endoscopic Simulation

Abstract

Inspection of the colon with an endoscope for early signs of cancer (colonoscopy) has become an extremely widespread procedure, since early treatment radically improves the outlook of patients. The procedure requires a close coordination between the sense of touch and vision to navigate the endoscope along the colon. This raises the need to develop efficient training methods for physicians. Training simulators based on virtual reality, where realistic graphics are combined with a mechatronic system providing haptic feedback, are alternative to traditional training methods. To provide physicians with realistic haptic sensations of an endoscopic procedure, we have designed a haptic interface, instrumented a clinical endoscope and combined them with a simulation software for colonoscopy. In this contribution, we present the mechatronic components of the simulator. The haptic interface is able to generate high forces using the combination of electrical motors and brakes in a compact design. Experiments were performed to determine the characteristics of the device. A model-based control has been implemented and the results show that the control successfully compensates for the device nonlinearities, such as friction. The proposed haptic interface, together with the virtual reality, form a highly realistic training simulator for endoscopic surgeons, applicable not only to colonoscopy, but also to similar interventions.

Design and Evaluation of a Cable-Driven fMRI-Compatible Haptic Interface to Investigate Precision Grip Control

“…Nevertheless, a reduction of approximately 10 dB can be observed in the range of 0.5–1.5 Hz from the uncontrolled to the controlled case. The relatively large Z-width identified for our device is comparable to the Z-width of other non-MR-compatible haptic devices [59] (very few research papers report Z-width measurements, and no references could be found for MR-compatible devices), and allows for future rendering of virtual objects with a wide range of mechanical properties, ranging from close to transparent (∼ 0.2 N friction force) to relatively stiff (3.3 N/mm) objects, and viscosities (viscous force fields) up to 85 N/(m/s). The static friction is lower (in particular due to cable transmission and friction compensation using the MR-compatible force sensor [42] attached at the output) than in the devices we previously developed [20] and also compared to other MRI-compatible haptic systems [60], which display higher output friction (∼ 3 N) even after performing friction compensation using force sensors at the output.…”

Development of a Haptic Interface for Natural Orifice Translumenal Endoscopic Surgery Simulation

“…Similar frequency response analysis on a 2 DOF haptic device has been performed before by Samur et al [13]. The translational and rotational DOF were both independently subjected to a 1–30 Hz chirp input signal excitation sequence with translational and rotational amplitudes of 2N and 0.1Nm respectively, while placed in the open ended and close ended configurations, separately.…”

“…Some simulators were built for training in a specific procedure while others allow general endoscopy based training. A 2 DOF haptic device for colonoscopy training was developed by Samur et al [13]. The device was designed to provide active and passive rotational and translational force-feedback to the user.…”

A simplified approach to admittance-type haptic device impedance evaluation

“…While some researchers have developed alternative methods to assess output impedance [6][7][8][9][10], these methods can be complex to implement, requiring experimental equipment capable of acting as a pure force source 1 over a wide frequency range or requiring acceleration measurement of the haptic interface, to name a few. As a consequence, it is difficult to assess and compare the performance of admittance-type devices in general.…”