High Speed Machining Direct from CAM

The DMAC machine controller consists of a PC workstation, and a fiber optic serial communications card interfaced to digital drive motor amplifiers and an I/O interface to the machine electrics. The PC workstation is outfitted with dual processors.  One of the processors is dedicated to running Microsoft Windows applications (such as CAD/CAM or robot simulation software). The other processor runs under a real-time operating system and is dedicated to controlling the machine tool through the digital drive amplifiers and digital I/O interfaces.

The entire controller, from high level motion planning through low level motor servo control, is implemented in software. A set of Application Programming Interfaces (APIs) are available for the CAD/CAM system (or other motion planning software) to pass path and process information to the controller software.

The DMAC process is radically different from the traditional CAD –> CAM –> Post-process–> CNC process. With DMAC the CAM software controls the CNC machine directly from the native process geometry, in much the same way that a standard Windows application controls a printer.  DMAC is to machine control as a printer driver is to printing.

Machining parts directly from the CAM model provides many advantages. The CAM model contains tool paths and machine operations in their native format as defined by the process engineer.  The traditional approach to machine tool control requires a minimum of two translations from this data before it ever reaches the controller.  The integrity of the data can be compromised each time it is translated. DMAC processes tool paths using whatever data format the CAM system uses internally - resulting in no approximations and therefore greater accuracy.

Post processing is a thing of the past.  Process data and tool path geometry drive the machine tool in their native CAM format .  All changes to the process, whether made by the CAM engineer or the machine tool operator, are made to the CAM model.