Computer-aided manufacturing
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Integrating computer-aided manufacturing (CAM) with computer-aided design systems produces quicker and more efficient manufacturing processes. This methodology is applied in different manufacturing areas.
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Things taken care of by CAM
- Verification of the data
- Panelization of the design to fit the raw material
- Ability to edit
- Ability to add manufacturing information
Data flow in mechanical engineering CAM
- First the information about a product is imported into the CAM system. Usually a CAD model is imported. The file may be a 3d model for milling machines. It may also be in the form of a 2d file for routers, lasers, waterjet or plasma tables.
- In mechanical engineering CAM is used to calculate toolpaths to cut material. Machining operations are calculated by using different functions that are offered by the CAM systems. The toolpath is usually written in CL data (Cutter Location data) format.
- The calculated toolpath is imported to the postprocessor which converts the CL data to the NC program for the specific machine. NC programs often use text files (which aid editing) and incorporate start and stop locations using an x,y,z grid. A simple example might be a 4" x 2" rectangle. The basic code might read something like:
N1X0Y0T01 N2X0Y2000 N3X4000Y2000 N4X4000Y0 N5X0Y0 N6M00
- Line 1 (N1) tells the machine to traverse to grid point X0Y0 and to pick tool #1
- Line 2 tells the machine to traverse to grid point X0Y2.000
- Line 3 tells the machine to travel to grid point X4.000Y2.000
- Line 4 tells the machine to travel to grid point X4.000Y0
- Line 5 returns the machine to origin
- Line 6 stops the machine
- Note that the program does nothing to define the tool cutting path. If the machine is a router and uses a 1/8" radius cutter, the actual part will end up 1/4" smaller than designed (1/8" per side). To compensate, a G-code command (in this case) may be used to adjust the tool path.
N1G44M0125 N2X0Y0T01 N3X0Y2000 N4X4000Y2000 N5X4000Y0 N6X0Y0 N7M00
- In this case, the controller sees the first line and adjusts the location of the cutter to .125 (or 1/8") to the outside of the cutting profile. Now the machine will make a part that matches the one designed. Depending on the cutting tool, the compensation can be set as needed. For example, a laser with a very fine beam might have a compensation of .005", while a waterjet with a .060 inside tip diameter may need a compensation of .030.
- NC program is exported to the NC machine and the manufacturing process can begin.
Areas of usage
- In mechanical engineering
- In electronic design automation, CAM tools prepare printed circuit board (PCB) and integrated circuit design data for manufacturing.
Brief description
In CNC manufacturing the CAM system is used to simplify the machining and design process. In most cases the CAM system will work with a CAD design made in a 3D environment. The CNC programmer will just specify the machining operations and the CAM system will create the CNC program. This compatibility of CAD/CAM systems eliminates the need for redefining the work piece configuration to the CAM system.
See also
- Computer Integrated Manufacturing (CIM)
- FMS (Flexible Manufacturing System)
- ICAM (Integrated Computer-Aided Manufacturing)
External links
- "What is a CAM system?" (http://www.pmozarks.com/article/cam_sys.htm)– By Mike Lynch
- "What are the differences between manual, conversational, and CAM system programming?" (http://www.cncci.com)de:Computer Aided Manufacturing
fr:Fabrication assistée par ordinateur ja:CAM pl:Wytwarzanie wspomagane komputerowo