In this paper, a virtual prototype system for control panels is presented by using an encountered-type haptic device. The system can render different switches arranged on a virtual control panel by a single haptic device. A motion planning algorithm for the encountered-type haptic device is proposed so that the device is properly encountered by the user at the switch locations while it avoids unintended collisions with the user elsewhere. To reduce the duty of the device motion, the weighting function in the algorithm is improved. Control panel surface coordinates are newly introduced in the motion planning so that unintended collisions of the device with the user are completely avoided in free space. The proposed motion planning algorithm with some improvements is verified by numerical simulations.