PURPOSE: To faciitate variation of bilateral response characteristics.

CONSTITUTION: A sum (A+B) of a value A obtained by multiplying information on an external force, transmitted from a slave, by a gain K1 and a value B obtained by multiplying a value totalized by multiplying movement information on acceleration, the speed, and the position of a slave arm, transmitted from a slave, by the factors of target inertia, target viscosity, and target elasticity by a gain K2 forms a control input to a master. A sum (C+D) of a value C obtained by multiplying information on an external force transmitted from a master by a gain K3 and a value D obtained by multiplying a value, totalized by multiplying movement information on acceleration, the speed, and the position of a master arm, transmitted from a master, by the factors of target inertia, target viscosity, and target elasticity, by a gain K4 forms a control input to the slave.