Abstract: This paper proposes a new method and implementation scheme for directly generating the function curve for machining functional curves to reach the specified feedrate. The speed control model for each axis is derived from the equation of the function curve being machined, and the speed of the stepper motor for each axis is directly controlled to achieve the given synthetic feedrate and motion trajectory at the machining point . Simultaneously, it effectively resolves the contradiction between precise stepping of the curve and the capacity of the control system. Simulation results verify the correctness and feasibility of the proposed control method. Keywords: Stepper motor; CNC; Feed rate; Control; Function curve Meanwhile the conflict between part precision and CNC machine's memory resolved． The motion accuracy and feasibility of the proposed method have been verified with provided intersecting curve example． Kye word: stepping motor; CNC; feedrate; control; funetional curves Click here to download the original text