Haptic Training Simulator Research Articles

Multimodal Haptic Simulation for Ventriculostomy Training.

Freehand ventriculostomy is a frequent surgical procedure and is among the first ones that junior neurosurgery residents learn. Although training simulators exist, none has been adopted in the clinical routine to train junior residents. This paper focuses on a novel multimodal haptic training simulator that will lift the limitations of current simulators. We thus propose an architecture that integrates (1) visual feedback through augmented MRIs, and (2) a physical mock-up of the patient's skull to (3) active haptic feedback.

Using an Improved Output Feedback MPC Approach for Developing a Haptic Virtual Training System

Haptic training simulators generally consist of three major components, namely a human operator, a haptic interface, and a virtual environment. Appropriate dynamic modeling of each of these components can have far-reaching implications for the whole system's performance improvement in terms of transparency, the analogy to the real environment, and stability. In this paper, we developed a virtual-based haptic training simulator for Endoscopic Sinus Surgery by doing a dynamic characterization of the phenomenological sinus tissue fracture in the virtual environment, using an input-constrained linear parametric variable model. A parallel robot manipulator equipped with a calibrated force sensor is employed as a haptic interface. A lumped five-parameter single-degree-of-freedom mass-stiffness-damping impedance model is assigned to the operator’s arm dynamic. A robust online output feedback quasi-min–max model predictive control framework is proposed to stabilize the system during the switching between the piecewise linear dynamics of the virtual environment. The simulations and the experimental results demonstrate the effectiveness of the proposed control algorithm in terms of robustness and convergence to the desired impedance quantities.

Review on Needle Insertion Haptic Simulation

Purpose of ReviewThis short review updates an exhaustive one written by Correa et al. in 2019 about haptic training simulation on needle insertion in the medical field.Recent FindingsLatest works refine well-known models and enhance setups and methods to facilitate generically getting experimental data.SummaryWe provide a complementary focus on device specifications and recent models to render this specific haptic feedback on computer-based simulators. Assessment approaches and the issues encountered when introducing such simulators into curricula are also discussed. FEM-based approaches still do not permit real-time computation but hybrid approaches as proposed by Wittek et al. in 2020 may become a good compromise. Nonetheless, psychophysical studies should be performed to determine the haptic fidelity of the various approaches found in the literature, and embed them efficiently in medical curricula. This would permit to delay the necessary final hands-on training on patients that raises ethical issues.

Design and Clinical Validation of a Robotic Ankle-Foot Simulator With Series Elastic Actuator for Ankle Clonus Assessment Training

To fulfill the need for reliable and consistent medical training of the neurological examination technique to assess ankle clonus, a series elastic actuator (SEA) based haptic training simulator was proposed and developed. The simulator's mechanism (a hybrid of belt and linkage drive) and controller (impedance control) were designed to render a realistic and safe training environment. Benchtop tests demonstrated that the prototype simulator was able to accurately estimate the interaction torque from the trainee (average RMSE of 0.2 Nm) and closely track a chirp torque command up to 10 Hz (average RMSE of <0.22 Nm). The high-level impedance controller could switch between different clinically encountered states (i.e., no clonus, unsustained clonus, and sustained clonus) based on trainee's assessment technique. The simulator was evaluated by a group of 17 experienced physicians and physical therapists. Subjects were instructed to induce sustained clonus using their normal technique. The simulator was assessed in two common clinical positions (seated and supine). Subjects scored simulation realism on a variety of control features. To expedite controller design iteration, feedback from Day 1 was used to modify simulation parameters prior to testing on Day 2 with a new subject group. On average, all subjects could successfully trigger a sustained clonus response within 4-5 attempts in the first position and 2-3 in the second. Feedback on the fidelity of simulation realism improved between Day 1 and Day 2. Results suggest that this SEA-based simulator could be a viable training tool for healthcare trainees learning to assess ankle clonus.

Haptic Training Simulation

Immersive virtual environments combined with haptic (kinaesthetic and/or tactile) feedback are becoming an essential building block of simulator training in a variety of applications. This paper aims to illustrate the interest of hands-on training simulation with haptic feedback. We review the recent application domains and we expose the progress and open challenges in the medical domain which is particularly demonstrative. The paper then addresses two aspects of haptic feedback that could help enhance modern haptic training simulators' performance, namely transparent and efficient actuation for kinaesthetic feedback and tactile feedback. This research topic, beyond technological progress, should help design kinaesthetic and tactile haptic interfaces and motivate the use of new actuation techniques for more realistic and effective feedback in simulations as soon as users are immersed in virtual environments.

Comparing and Combining Time Series Trajectories Using Dynamic Time Warping

This research proposes the application of dynamic time warping (DTW) algorithm to analyse multivariate data from virtual reality training simulators, to assess the skill level of trainees. We present results of DTW algorithm applied to trajectory data from a virtual reality haptic training simulator for epidural needle insertion. The proposed application of DTW algorithm serves two purposes, to enable (i) two trajectories to be compared as a similarity measure and also enables (ii) two or more trajectories to be combined together to produce a typical or representative average trajectory using a novel hierarchical DTW process.Our experiments included 100 expert and 100 novice simulator recordings. The data consists of multivariate time series data-streams including multi-dimensional trajectories combined with force and pressure measurements.Our results show that our proposed application of DTW provides a useful time-independent method for (i) comparing two trajectories by providing a similarity measure and (ii) combining two or more trajectories into one, showing higher performance compared to conventional methods such as linear mean. These results demonstrate that DTW can be useful within virtual reality training simulators to provide a component in an automated scoring and assessment feedback system.

An Augmented Reality Haptic Training Simulator for Spinal Needle Procedures

This paper presents the prototype for an augmented reality haptic simulation system with potential for spinal needle insertion training. The proposed system is composed of a torso mannequin, a MicronTracker2 optical tracking system, a PHANToM haptic device, and a graphical user interface to provide visual feedback. The system allows users to perform simulated needle insertions on a physical mannequin overlaid with an augmented reality cutaway of patient anatomy. A tissue model based on a finite-element model provides force during the insertion. The system allows for training without the need for the presence of a trained clinician or access to live patients or cadavers. A pilot user study demonstrates the potential and functionality of the system.

Shared control architectures for haptic training: Performance and coupled stability analysis

A novel shared control architecture is presented for dual-user haptic training simulation systems for enhanced interaction between the users and between each user and the virtual environment. The coupled stability of the proposed control architecture against uncertainties in the environment and the user’s dynamics is investigated using the three-port master–slave network model of the dual-user haptic simulation system. For this purpose, Llewellyn’s unconditional stability criterion is applied to an equivalent two-port network model obtained from the corresponding three-port network, considering the environment as a load termination. The kinesthetic performance of the proposed architecture is numerically analyzed for transparency and evaluated against a benchmark control architecture under different operating conditions, such as various types of environments, users’ grasps, and levels of dominance of users over the task. An experimental user study is carried out to assess the effectiveness of the proposed architecture in terms of users’ perception of environment stiffness sensing, device agility, and haptic guidance reception.

Augmented, Pulsating Tactile Feedback Facilitates Simulator Training of Clinical Breast Examinations

Haptic training devices can facilitate tactile skill development by providing repeatable exposures to rare stimuli. Extant haptic training simulator research primarily emphasizes realistic stimuli representation; however, the experiments reported herein suggest that providing augmented feedback can improve training effectiveness, even when the feedback is not natural. A novel clinical breast examination training device uses inflated balloons embedded in silicone to simulate breast lumps. Oscillating the balloon water pressure makes the lumps pulsate. The pulsating lumps are easier to detect than the static lumps used in current simulators, and this manipulation seems to effectively introduce trainees to small, deep lumps that are initially difficult to perceive. A study of 48 medical students indicates that training with the dynamic breast model increased the number of lumps detected, F(1, 47) = 9.34, p = .004, decreased the number of false positives, F(1, 47) = 5.78, p = .020, and improved intersimulator skill transfer, F(1, 47) = 26.56, p < .001. The results suggest that at least in this case, augmented, tactile feedback increases training effectiveness, despite the fact that the feedback does not attempt to mimic any physical phenomenon present in the natural stimulus. Applications of this research include training techniques and tools for improved detection of palpable cancers.