Abstract: This paper introduces an open CNC system applicable to both virtual axis tool grinding machines and conventional tool grinding machines. The hardware and software structures of the control system are presented, along with an example of grinding helical drill bits on both machines. Keywords : Digital control system; tool grinding machine; grinding; virtual axis machine tool; drill tip grinding. Traditional CNC machine tools have their motion axes arranged in series in a Cartesian coordinate system, with each axis's theoretical position achievable independently through its respective servo system. Machine tools manufactured in this manner are easy to calculate and control. However, virtual axis machine tools are different. The tool trajectory and the displacement of each link have a complex nonlinear relationship, with coupling and interference existing between the links. Furthermore, tool grinding requires complex mathematical transformations, which determines the unique characteristics of the CNC system for tool grinding machines. Beijing University of Aeronautics and Astronautics (BUAA) began research and development of CNC tool grinding machines in the 1980s, developing several models. To maximize the utilization of existing research results, BUAA developed a CNC system suitable for both virtual-axis and traditional CNC tool grinding machines. The implementation of this CNC system is briefly described below. 1. CNC System Structure of the CNC Tool Grinding Machine The CNC system design of the CNC tool grinding machine embodies a certain degree of openness. It is a PC-based CNC system, with the main functions performed by the PC. It connects to the machine tool only via a 24in/24out digital input/output interface board and a simple motion control board. Real-time and non-real-time functions are coordinated and completed in software within the PC. The system provides users with a control interface and a common language (such as VC) environment, allowing users to set machine tool structural parameters and adjust controllable parameters online. Users can add functional modules using VC to meet special requirements. The software adopts a modular design, possessing reconfigurability and portability. [b][align=center]For details, please click: CNC System Applicable to Virtual Axis and Conventional Tool Grinding Machines[/align][/b]