PURPOSE: To control a displacement amount of a stylus so as to be fixed, so that accurate copying control can be performed, in a pencil copying control system of manually moving a stylus to copy a model surface.

CONSTITUTION: The first stylus 27 in a tracer head 26 is a stylus displaced by manual operation, and on the other hand, the second stylus 28 is a stylus displaced into contact with a surface of a model 29. A feed command speed arithmetic circuit 41 calculates feed command speeds Vmx, Vmy, Vmz of copying in accordance with each displacement amount of an operating transformer 27a. A synthesizing circuit 43 calculates a synthetic displacement amount of a displacement amount of an operating transformer 28a. An adder 44 calculates a displacement difference Δ between this synthetic displacement amount and a reference displacement amount 0 set previously by a parameter or the like, to calculate, based on the displacement difference Δ, a copying command speed Vn of a shaft of copying displacement of a model surface by a copying command speed arithmetic circuit 45. An output shaft select circuit 42, in accordance with a select command of a copying mode set by a mode setting image plane, selects an output shaft.