Abstract: A robot device of the present disclosure includes at least one artificial muscle that operates by being supplied with liquid; and a liquid supply device that supplies and discharges the liquid to/from the artificial muscle, and the liquid supply device includes: a liquid storage part that stores the liquid; a pressure regulating valve that regulates pressure of the liquid from the liquid storage part and supplies the liquid to the artificial muscle; and a liquid keeping part that allows the artificial muscle to keep the liquid supplied to the artificial muscle, according to occurrence of an abnormality, and the liquid supply device can allow the artificial muscle that operates by being supplied with liquid to operate properly.