In this research, we allowed duplicate gestures according to on operation mode to reduce the number of gestures and avoid confusion. Most users were able to input the defined gestures easily on our system. However, a few users were confused about how many fingers they should use to enter the cut, sweep, and datum planeWhen users were confused, we provided a table containing information on the number of fingers necessary for each function. This helped the users to create a proper model. There appears to be a problem caused by the mapping of multiple functions to a single motion for simplified input. Therefore, a study that determines the optimal numbers of gestures and functions is needed in the future to enhance user understanding. Above all, the primary ben