The insertability of an insertion portion of a medical device is enhanced by controlling driving of a bending portion of the insertion portion so that the bending portion takes a shape conforming to the internal shape of a tube cavity. To this end, a controller 5 includes a servo controller 36A that performs attitude control of the bending portion 14. A point lock computing section 50 is provided at the servo controller 36A. Based on supplied distal end command value information and position F/B information, the point lock computing section 50 performs computational processing by a distal end link root coordinate position calculating section 51 and an inverse kinematics computing section 52 in order to obtain a servo position command signal for a distal end-side link member 21a1 and a servo position command signal for a link member other than the link member 21a1, and outputs the same to a driving section 10b. Accordingly, point lock is enabled at two locations, namely, the distal end-side link member 21a1 and an arbitrary link member 21a, while other link members 21a are controlled so as to assume attitudes having redundancy.
