The goal of this research was to design an artificial hand and bow force-adjusting system for playing the violin and to validate its effectiveness. The hand had five solid fingers without rotary joints. Instead, a chamber covered with a silicone rubber membrane was placed in each finger, except for the thumb. When the air pressure in the chamber is increased using an electric pneumatic regulator, the membrane inflates, which increases the force required to push the bow stick. We fabricated a hand and installed it on our 7-degrees-of-freedom manipulator. We conducted preliminary experiments to obtain the basic characteristics of the hand and built a bow force-adjusting system. We performed an experiment to confirm that the bow force could be adjusted by increasing or decreasing the air pressure in the index and little fingers. Thus, the bow force was successfully adjusted to the target using the artificial hand.

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