Virtual and Augumented Reality

Research in collaboration with Sri Kurniawan and her ASSIST Lab

Elor, A., Powell, M., Mahmoodi, E., Hawthorne, N., Teodorescu, M., & Kurniawan, S. “On Shooting Stars: Comparing CAVE and HMD Immersive Virtual Reality Exergaming for Adults with Mixed Ability” To appear in ACM Transactions on Computing for Healthcare (HEALTH), 20. ACM, (2020) Paper

Abstract— Inactivity and a lack of engagement with exercise is a pressing health problem in the United States and beyond. Immersive Virtual Reality (iVR) is a promising medium to motivate users through engaging virtual environments. Currently, modern iVR lacks a comparative analysis between research and consumer-grade systems for exercise and health. This paper examines two such iVR mediums: the Cave Automated Virtual Environment (CAVE) and the Head-Mounted Display (HMD). Specifically, we compare the room-scale Mechdyne CAVE and HTC Vive Pro HMD with a custom in-house exercise game that was designed such that user experiences were as consistent as possible between both systems. To ensure that our findings are generalizable for users of varying abilities, we recruited forty participants with and without cognitive disabilities concerning the fact that iVR environments and games can differ in their cognitive challenge between users. Our results show that across all abilities, the HMD excelled in-game performance, biofeedback response, and player engagement. We conclude with considerations in utilizing iVR systems for exergaming with users across cognitive abilities.

Elor, A., Teodorescu, M., & Kurniawan, S. "Project star catcher: A novel immersive virtual reality experience for upper limb rehabilitation." ACM Transactions on Accessible Computing (TACCESS), 11(4), 1-25. (2018)

Abstract— Modern immersive virtual reality experiences have the unique potential to motivate patients undergoing physical therapy for performing intensive repetitive task-based treatment and can be utilized to collect real-time user data to track adherence and compliance rates. This article reports the design and evaluation of an immersive virtual reality game using the HTC Vive for upper limb rehabilitation, titled “Project Star Catcher” (PSC), aimed at users with hemiparesis. The game mechanics were adapted from modified Constraint Induced Therapy (mCIT), an established therapy method where users are asked to use the weaker arm by physically binding the stronger arm. Our adaptation changes the physical to psychological binding by providing various types of immersive stimulation to influence the use of the weaker arm. PSC was evaluated by users with combined developmental and physical impairments as well as stroke survivors. The results suggest that we were successful in providing a motivating experience for performing mCIT as well as a cost-effective solution for real-time data capture during therapy. We conclude the article with a set of considerations for immersive virtual reality therapy game design.

Lessard, S., Pansodtee, P., Robbins, A., Trombadore, J. M., Kurniawan, S., & Teodorescu, M. “A Soft Exo-suit for Flexible Upper-Extremity Rehabilitation. IEEE Transactions on Neural Systems and Rehabilitation Engineering”, 26(8), 1604-1617. (2018).

Abstract— For stroke survivors and many other people with upper-extremity impairment, daily life can be difficult without properly functioning arms. Some modern physical therapy exercises focus on rehabilitating people with these troubles by correcting patients' perceptions of their own body to eventually regain complete control and strength over their arms again. Augmentative wearable robots, such as the upper-extremity exoskeletons and exosuits, may be able to assist in this endeavor. A common drawback in many of these exoskeletons, however, is their inability to conform to the natural flexibility of the human body without a rigid base. We have built one such exosuit to address this challenge: Compliant Robotic Upper-extremity eXosuit (CRUX). This robot is a compliant, lightweight, multi-DoF, portable exosuit that affords its wearer the ability to augment themselves in many unconventional settings (i.e. outside of a clinic). These attributes are largely achieved by using a modified tensegrity design situated according to measured lines of minimal-extension, where a network of tension members provide a foundation to apply augmentative forces via precisely placed power-lines. In this paper, we detail the design process of CRUX, the report on CRUX's prototypical composition, and describe the mimetic control algorithm used. We also discuss the results of three studies that illustrate the efficacy of CRUX's mimetic controller, CRUX's flexibility and compliance, and the metabolic cost reduction when users exercise with assistance from CRUX as opposed to without. We conclude this paper with a summary of our findings, potential use cases for this technology, and the direction of future related work.