Raj Arjunan

Bio: Raj Arjunan is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Competence (human resources) & Modal analysis. The author has an hindex of 2, co-authored 3 publications receiving 6 citations.

Affordable hi-fidelity VR based CPR simulator with haptics feedback

Abstract: Haptic skills are essential for effective Cardiopulmonary Resuscitation (CPR). Existing CPR training simulators provide unrealistic chest conditions. It is assumed that the CPR performance on a real human chest is the same even when the trainees have learnt on unrealistic dummy chests. To test this assumption we have developed an immersive Virtual Reality based CPR simulator in which force feedback is provided using a dummy chest with a linear spring mounted on a force plate. The user applied force is mapped to visual chest compressions modeling various springs, either linear or non-linear. Two groups of subjects were trained either with linear or non-linear chests. Both the groups were tested for their CPR performance on an unknown non-linear chest and their performance score was compared. The % of mean and standard deviation of the score (p value: 0.001) for the group with the non-linear chest is 91.66% and 1.70% and that with linear chest is 86.39% and 3.44% respectively. This suggests that the group that were trained on non-linear chest performed better. The experiments clearly demonstrates that visual feedback could influence haptics perception of chest compliance and the VR-CPR system could simulate various linear and non-linear chest compliance controlling visual feedback alone.

The Effect of Audio and Visual Modality Based CPR Skill Training with Haptics Feedback in VR

Abstract: The hypothesis of this study is to verify the sensory dominance with the combinations of three sensory modalities (Audio-Haptics (AH), Visual-Haptics (VH), Audio-Visual-Haptics (AVH)) using Virtual Reality (VR) based Cardiopulmonary Resuscitation (CPR) simulator. To test this hypothesis three experiments with three different groups of participants were conducted with the above three modes of combinations. Finally, three groups were tested for their CPR performance on an unknown linear chest stiffness of mannequin-based CPR simulator and their performance score was compared. The % mean and standard deviation of the performance score (p-value: 0.00006) in the testing phase for group A-AH, B-VH, and C-AVH is $77.95\%\pm 8.27\%, 89.47\%\pm 6.19\%, \ \text{and} \ 91.73\%\pm 3.14\%$ respectively. The results show that the group who trained with the three sensory modalities have better performance than that of the other two groups. Our future work is to incorporate rescue breathing in the CPR training simulator for better skill training.

Digital Health Interventions to Enhance Patient Care for Indian Nurses

Abstract: The health care and nursing profession in India has suffered neglect both historically and in present times. We propose the use of information and communication technology-assisted learning (ICTAL) for creating a large capacity of qualified, skilled, and competent health care workforce in a short period. The “Indian Nursing Knowledge System (INKS)” an online platform uses a blended learning approach with, including, but not limited to customized, individualized digital health content, maximum utilization of smartphones, Web portal, SMART products, simulations, with inter-sectoral coordination with sectors of society addressing health and well-being. We envisage improving nurses’ clinical skills, competence, critical thinking, decision making, and the ability to work in teams.

H-Matrix BEM application and validation for space habitat

Abstract: Acoustic requirements for space habitats are stringent and involve a combination of noise sources minimization and public address and general alarm (PAGA) system validation. Simulation solutions are essential for demonstrating compliance requirement as early as possible and continuously throughout the development cycle of the spacecraft. Space habitats' sound field can be computationally challenging to predict in a deterministic manner for most of the audible spectrum as the volume can be important. For this application, an initial PAGA system design assessment was performed using Ray-Tracing, a geometric statistical method, which must be validated using a deterministic method. For validation purpose, the Boundary Element Method (BEM) was chosen for this application. Given the size of the structure and the desired frequency range, the BEM model was very large, containing over 250,000 wetted nodes, and a standard BEM solver required approximately 200GB of RAM. To limit computing hardware constraints, a newly implemented commercially available H-Matrix BEM solver was used. Pressure maps of a PAGA system simulation on a generic space habitat resulting from the Ray-Tracing and H-Matrix BEM solvers are compared to a standard BEM simulation. Results are compared both in terms of accuracy and computational performance, showing the advantages of using multiple simulation methods at various stages of the design.

Acoustically Induced Vibration Mitigation

Abstract: Reduction of the fatigue risk presented by acoustically induced vibration in flare header systems using mitigations that either reduce dynamic stress concentration effects or the level of vibration are of considerable interest to designers and plant operators. Assessments of the relative performance of different types of pipe fittings in reducing dynamic stress levels are presented based on the evaluation of data from full-scale laboratory tests of a pressure-relief system. A modal-analysis based finite-element methodology is also developed so that predictions may be extended to other piping arrangements that vary in thickness, size or connection type. The pipe fittings considered in the test are Pipet®, fabricated tee (Stub-on arrangement), sockolet (small-bore branch connections only), full-wrap reinforced fabricated Tee and Sweepolet®. For the finite-element method reducing tee connection is considered in addition. The test system produced significant levels of both turbulent-induced vibration (FIV) and acoustically induced vibration (AIV), which required differentiation of stress evaluations for the low-frequency FIV region and the mid-to-high frequency AIV region. The relative performance of mitigations (through selection of the type of pipe fitting) was found to be particularly relevant in the low-frequency FIV region. The reductions in dynamic stress and vibration of small-bore branch connections from installation of clamped bracing are also presented. The results show that the use of reducing Tees and full-wrap reinforcements for Stub-on connections for tailpipe and sub-header branch connections provide significant mitigation of dynamic stress and improvement of fatigue life over the use of Pipet® and Stub-on fittings. However, for the Sweepolet® connection which was expected to provide similar improvement the benefits are not fully realized in the 10S configuration.

A systematic review of immersive virtual reality for industrial skills training

Abstract: Virtual reality (VR) training offers the capability to industrial workers to acquire skills and address complex tasks by immersing them in a safe and controlled virtual environment. Immersive VR (I...

Virtual Reality and Haptic Cardiopulmonary Resuscitation Training Approaches: A Review

Abstract: Cardiac arrest is a leading cause of death worldwide preventable with timely application of cardiopulmonary resuscitation (CPR). The American Heart Association CPR guidelines recently have an increased focus on quality of consistent chest compressions and highlighted the need for frequent refresher courses. Literature has shown that standard training manikins do not accurately represent human torso compression forces. Virtual reality (VR) and augmented reality (AR) technologies can simulate or enhance training environments and have shown promise for CPR training. Haptics is the touch element of virtual experiences and the literature has suggested that haptics can produce higher fidelity force feedback over standard training manikins. This review aims to determine the state of research of virtual and AR and haptic-enabled CPR training systems. VR approaches examined feedback, visual kinesthetic manipulation, and gamification. Systems using AR have examined the potential benefits of real-time feedback and quick reference. Haptic approaches have examined different mechanisms and design principles for reproducing realistic human CPR. Hybrid systems explore collaborative training and methods for immersion. These systems offer the potential for immersive training and realistic haptic rendering. However, to reach widespread adoption they must overcome the limitations of cost and mechanical complexity.

The Effect of Audio and Visual Modality Based CPR Skill Training with Haptics Feedback in VR

Abstract: The hypothesis of this study is to verify the sensory dominance with the combinations of three sensory modalities (Audio-Haptics (AH), Visual-Haptics (VH), Audio-Visual-Haptics (AVH)) using Virtual Reality (VR) based Cardiopulmonary Resuscitation (CPR) simulator. To test this hypothesis three experiments with three different groups of participants were conducted with the above three modes of combinations. Finally, three groups were tested for their CPR performance on an unknown linear chest stiffness of mannequin-based CPR simulator and their performance score was compared. The % mean and standard deviation of the performance score (p-value: 0.00006) in the testing phase for group A-AH, B-VH, and C-AVH is $77.95\%\pm 8.27\%, 89.47\%\pm 6.19\%, \ \text{and} \ 91.73\%\pm 3.14\%$ respectively. The results show that the group who trained with the three sensory modalities have better performance than that of the other two groups. Our future work is to incorporate rescue breathing in the CPR training simulator for better skill training.