China's CNC machine tools gradually transition to processing units

Researcher Luo Baihui believes that “the current technological level of the world's machine tools is mainly driven by the production of CNC machine sheet machines. The development in the next 20 years will also be the case.” Based on further improvement in accuracy, efficiency, automation, intelligence, and networking CNC machine tools are gradually transitioning to machining units and cutting-edge flexible manufacturing systems.

China's "National Medium and Long-Term Plan for Scientific and Technological Development (2006-2020)" regards "the major special projects of high-end CNC machine tools and basic manufacturing equipment" as one of the 16 national major scientific and technological special projects, and clearly puts forward the goal of developing China's high-end CNC machine tools. The development and application of high-end CNC machine tools put forward higher requirements for CNC systems. High-speed and high-precision motion control has become a key technology of modern CNC systems. It has received widespread attention at home and abroad, and has undergone a lot of research from theoretical methods to practical applications. Practice has effectively promoted the technological progress of high-end CNC machine tools.

The goal of Cnc Machining is to achieve high speed, high precision and high efficiency machining. How to ensure the optimal acceleration and deceleration control law with the shortest transition time as the goal under the premise of smooth motion of the machine tool, so that the machine tool has the acceleration and deceleration characteristics to meet the requirements of high-speed machining, is a key issue in the study of acceleration and deceleration. Acceleration and deceleration control schemes usually have two kinds of pre-acceleration and deceleration control and post-acceleration and deceleration control: pre-acceleration and deceleration control is generally located before interpolation and after interpolation preprocessing. The object of acceleration and deceleration control is the command feedrate; post-acceleration and deceleration control After the interpolator and before the servo controller, the feedrate of each motion axis is controlled. After the acceleration/deceleration control does not need to calculate the deceleration point, the algorithm is relatively simple, but if the servo gain of each movement axis is different, it is easy to cause a large trajectory profile error and affect the movement accuracy.

Therefore, the current acceleration and deceleration control technology is mainly applied. Acceleration and deceleration control methods can be summarized as traditional acceleration and deceleration methods and flexible acceleration and deceleration methods: traditional acceleration and deceleration methods are trapezoidal acceleration and deceleration methods and exponential acceleration and deceleration methods; flexible acceleration and deceleration methods are trigonometric acceleration and deceleration methods, S curve acceleration and deceleration methods And polynomial acceleration and deceleration methods. The traditional trapezoidal and exponential acceleration and deceleration affect the smoothness of motion due to abrupt acceleration, and the flexible acceleration and deceleration have received much attention in high-speed machining because of continuous acceleration.