Assessment of Force Feedback Models in a Haptic Device Using Alignment Accuracy and Brain Activity.

When controlling a robot's velocity, it is necessary to provide force feedback to the user, which shows the amount of input from the neutral position. In this paper, we introduce three distinct force feedback models, each with one or two parameters, and investigate the influence on the operability of the robot and brain activity according to the changes of the force feedback model using a haptic device. Participants in the alignment task performed tasks in which they aligned an object with a target position in virtual space using our developed interface while we measured the participant's operational performance and brain activation using functional near-infrared spectroscopy. We performed fitting using quadratic functions with the parameters of each model as design variables. The results of the alignment task demonstrated that two models achieved higher alignment performance depending on the position of the target from the neutral position and, for one model, brain activation changed significantly as the parameters changed.