Large force scaling bilateral control using voice coil motor with thrust compensation

Many researchers have studied the development of micromanipulation robots in order to allow for the medical operation such as microsurgery. In addition, the touching sensation must be amplified in micro manipulation because the environment is too fragile. In particular, acquiring the impulsive reaction force is needed to detect contact. A haptic amplification system based on Voice Coil Motor (VCM) to transmit the minute touching sensation was developed and described in this paper. Proposed system can acquire minute impulsive reaction force and attain large scaling bilateral control. However there is a problem that thrust constant is varied in accordance with the position of coil. This phenomenon makes it difficult to measure the reaction force accurately if using RFOB to estimate the reaction force. In this paper, a method to compensate fluctuation of thrust constant is described. In the first experiment, the effectiveness of compensation method is confirmed by force control. In the second experiment, the slave robot was made contact with the environment and the force was amplified to 10000.0 and transmitted to master robot. Validity of these methods is verified through the experimental results.