Improving Haptic Response for Contextual Human Robot Interaction.

For haptic interaction, a user in a virtual environment needs to interact with proxies attached to a robot. The device must be at the exact location defined in the virtual environment in time. However, due to device limitations, delays are always unavoidable. One of the solutions to improve the device response is to infer human intended motion and move the robot at the earliest time possible to the desired goal. This paper presents an experimental study to improve the prediction time and reduce the robot time taken to reach the desired position. We developed motion strategies based on the hand motion and eye-gaze direction to determine the point of user interaction in a virtual environment. To assess the performance of the strategies, we conducted a subject-based experiment using an exergame for reach and grab tasks designed for upper limb rehabilitation training. The experimental results in this study revealed that eye-gaze-based prediction significantly improved the detection time by 37% and the robot time taken to reach the target by 27%. Further analysis provided more insight on the effect of the eye-gaze window and the hand threshold on the device response for the experimental task.

Computer-Mediated Therapies for Stroke Rehabilitation: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate the efficacy of different forms of virtual reality (VR) treatments as either immersive virtual reality (IVR) or non-immersive virtual reality (NIVR) in comparison to conventional therapy (CT) in improving physical and psychological status among stroke patients. METHODS: The literature search was conducted on seven databases: ACM Digital Library, Medline (via PubMed), Cochrane, IEEE Xplore, Web of Science, Scopus, and science direct. The effect sizes of the main outcomes were calculated using Cohen's d. Pooled results were used to present an overall estimate of the treatment effect using a random-effects model. RESULTS: A total of 22 randomized controlled trials were evaluated. 3 trials demonstrated that immersive virtual reality improved upper limb activity, function and activity of daily life in a way comparable to CT. 18 trials showed that NIVR had similar benefits to CT for upper limb activity and function, balance and mobility, activities of daily living and participation. A comparison between the different forms of VR showed that IVR may be more beneficial than NIVR for upper limb training and activities of daily life. CONCLUSIONS: This study found out that IVR therapies may be more effective than NIVR but not CT to improve upper limb activity, function, and daily life activities. However, there is no evidence of the durability of IVR treatment. More research involving studies with larger samples is needed to assess the long-term effects and promising benefits of immersive virtual reality technology.