ABSTRACT
The objective of this study was to conduct a preliminary usability evaluation of a virtual reality (VR) simulator designed for training or retraining fine motor skills. The simulator was to be used to investigate the effects of visual display and haptic technology features on motor control rehabilitation and learning. The simulator modeled a block design task from the Wechsler Abbreviated Scale of Intelligence with augmented haptic control and visual feedback. Participants subjectively evaluated the usefulness and effectiveness of the simulation and provided comments regarding enhancements to the original design. Usability problems were categorized as haptic or visual-spatial. Some users had difficulties grasping and rotating a penlike stylus interface through more than 90 degrees at the wrist. Adjusting the system control-response (C/R) ratio and simplifying virtual block grabbing mechanisms were proposed as potential solutions. In terms of the visual-spatial challenges, field dependent users were expected to have difficulty in recognizing how the position and orientation of each virtual block uniquely contributed to overall designs in the simulation. Furthermore, since a user’s visual perspective in the VR was fixed they were expected to have less awareness of color patterns on blocks. Superimposing a grid on the stimulus design and making blocks translucent to reveal patterns on each side were proposed as potential solutions. Through system testing, a preferred C/R ratio was determined and grasping blocks by contact appeared useful for reducing unnecessary hand reorientations with the stylus. Performance problems related to haptic input and feedback were reduced to a greater extent than those related to visual-spatial issues.
