It always amazes me, the sheer complexity of the task. We must take a detailed engineering design, start with a simple block of metal, and through the application of pressure and process, whittle that block down to a functional product, accurate to within microns.
In order to accomplish this feat more efficiently and bring the cost/part down, CNC Machine Tools have added more of everything in recent years. They have become more powerful, allowing for higher cutting speeds that require advanced feed-rate controls to make effective. They have also become more dynamic, with 5-Axis Mills and multi-spindle, multi-turret Mill-turn machines offering opportunities to minimize part setups, increase accuracy, and reduce overall machining time.
They have, in short, become more complex. And with that complexity comes additional expense. With machines that routinely cost multiple hundreds of thousands, if not millions of dollars, the reality of the situation is that a machine collision is just not an option.
There are so many capabilities and options available on a modern NC Machine tool that ensuring that the machine is properly programmed to do what is expected becomes a monumental task. You need a powerful programming tool to help you create the paths, controlling the cutting tool axis, speeds, engagements and retracts so as to efficiently and accurately machine the product.
Those paths, when initially reviewed by the CAM software, may look feasible from the context of the tool, but upon generating the code and loading it into the controller, often there are motions that are either positional in nature (rotating the part to align the tool), or controller specific (ex. Go home moves) that create collisions with objects such as fixtures or the part, or that require movement beyond the machine’s axis limitations.
It becomes imperative, then, to simulate our toolpaths, and not only the basic simulation in the context of the tool that is common in so many CAM systems. NX CAM ISV (Integrated Simulation and Verification) allows us to build complete and accurate representations of even our most complex machine tools. The Machine tool builder within NX CAM ISV allows us to define the kinematic capabilities of the machine such as axis of rotation and travel limits based upon CAD geometry. The Post builder included with all NX CAM installations gives us an easy-to-use GUI with control over all aspects of our output G and M codes, cycle statements, and macros. And we are able to put all of that together, simulating not just the internal go to points from the CAM system, but actually sending the code through the post-processor and simulating the controller’s interpretation of the resulting G and M code. This ensures that we are simulating the exact code that will be running on the machine, giving us the confidence that what we see in the simulation is accurate, with program prove out done offline.
This ability to simulate posted code is just the beginning of the ISV’s capabilities. We are also able to define collision pairs between any pieces of geometry. We can track the tools travel, both non-cutting and cutting, in order to minimize extraneous positional movement. We can even read in outside Gcode from operations not programmed in NX CAM and still simulate the process.
Most CAM systems have parts of these capabilities, or require multiple expensive modules or costly translations in order to achieve what NX CAM can do out of the box due to its integrated nature. There are even specialized simulation software programs that focus solely on doing this sort of machine simulation. But often the process of exporting a program, geometry, fixtures and tooling becomes cumbersome enough that simulation is only done as a final step, eliminating the opportunity for path improvement in subsequent checks. In NX CAM, as we define each operation, it is quick and easy for us to jump into simulation, with no translations and without leaving our normal user interface; therefore we as users do not hesitate to check our work and improve the path based upon that feedback.
NX CAM Integrated Simulation and Verification is just one more example of Siemens leading the way in the digital engineering and manufacturing industry.
Latest posts by Casey Pratt (see all)
- Machine Simulation you can trust in NX CAM ISV - January 6, 2017
- Siemens NX 11 – Past and Future - October 19, 2016
- Revolutionizing Shape Design with NX Realize Shape - July 25, 2016