Visual Perspective and Feedback Guidance for VR Free-Throw Training

Abstract

Accurate distance perception and natural interactions are mandatory conditions when training precision aiming tasks in VR. However, many factors specific to virtual environments (VEs) lead to differences in the way users execute a motor task in VR versus the real world. To investigate these differences, the authors performed a study on basketball beginners' free-throw performance in VEs under different visual conditions. Although the success rate is not statistically different, some adaptations occurred in the way the users performed the task, depending on the visual conditions. In the third-person perspective visual condition, the release parameters indicate that the users more accurately estimated distance to target. Adding visual guidance information (gradual depth information showing the ideal ball trajectory) also led to more natural motor behavior. The final aim of this study was to develop a reliable basketball free-throw training system in VEs, so the authors compared beginners' performances in VR with experts' models of performance. Their results show that most of the performance variables tended to evolve closer to the experts' performance during the training in the VE.

EBAGG: Error-Based Assistance for Gesture Guidance in Virtual Environments

“…Trainees had to pass the forceps blades the closest to the center of those spheres to perform as good as the reference. Covaci et al [2] displayed the ideal trajectory with ellipses representing the position of the ball in a basketball free-throw simulator, in like manner as Moreau's guide spheres. However, these types of feedback are not reactive and not adaptive to the users' gestures.…”

“…It involves physiological and cognitive mechanisms, making some complex tasks or gesture hard to perform. On the other hand, VR has shown some promising solutions in various fields such as sport [2], medical science [3] or technical gesture [4].…”

A study on improving performance in gesture training through visual guidance based on learners' errors

“…In [Covaci et al 2015], Covaci et al proposed a basketball free-throw simulator and analyzed the transfer of motor skills from training in virtual environments to real practice. The authors compared several training paradigms, looking in particular at the effectiveness of visual guidance.…”

“…Thus we decided to design a 3D path of the reference gesture as shown in Figure 1-(a). The path was composed of a number of red segments positioned along the ideal motion in the same way as in [Covaci et al 2015;Moreau et al 2007]. Subjects were required to follow this path to reproduce the reference gesture.…”

“…Immersive environments are known to be valuable tools for training in a variety of contexts including sporting performance [Covaci et al 2015], the health sector [Moreau et al 2007] and even assembly and maintenance scenarios [Louison et al 2017]. Learners can train in safer and longer training sessions than in real environments, which has particular advantages in scenarios such as industrial maintenance where conditions are difficult.…”