A device including: a command-generator outputting a drive command signal to a drive unit; a detector outputting a position-detection signal of the drive unit; a drive-current detector outputting a drive-current detection value; a controller receiving the drive command and position-detection signals to generate a drive-force command signal, and supplying the drive current according to the drive-force command signal and the drive-current detection value; a friction-characteristics-estimator receiving a drive force signal and the position-detection signal to output a friction-characteristics estimate value; a temperature-information acquirer outputting a temperature information value; a friction modeling unit having a set reference friction model having temperature-dependent characteristics, and outputting reference friction characteristics based on the temperature information value; and a friction-variation analyzer outputting a friction variation value based on variation of the friction-characteristics estimate value from the reference friction characteristics.