Adaptive machining

Measuring probe

Previously, I posted an article on reducing operator intervention, which basically outlined ways to automatically make changes to a part set up or process without the operator doing any work. This cuts down on calculator and keypunch errors and increases uptime. With the goal of having a completely computer/CNC controlled operation we can strive to take the operator completely out of the process and observe continuous operation twenty-four/seven with no coffee or rest room breaks and take errors to almost zero.  This is probably an impossible task but using a combination of machine functions, tool life management and measuring probe applications you can custom form a process that is efficient, significantly reduces the occurrence of nonconformities. With the extra man-hours achieved you can now have an operator run two or even more machines.

A measuring probe is at the heart of this operation and it will be necessary to use all of its functionality.  Probes can and should be used for processes other than just in machine CMM functions. They can also be used effectively to set tool heights with grouped tools in the ATC, probe and make wear offsets, setting work offsets and fixture identification.  The list goes on and on and is limited only by your ingenuity. By probing and storing desired data and referencing system variables for position, distance to go or any other pertinent machine data, the value for almost any unknown can be calculated and used in your programs. Study the chapter in your operator’s manual that describes custom macro programming and familiarize yourself with the system variable list and decision-making operators.

Part programming can play an important role in adaptive machining through the use of interrupt programs. Use what you learned about probes and macro programming to make decisions when and where process modifications need to be made then invoke an interrupt call at those points to logically call the correct program in each instance. Be sure to learn the difference between sub program and macro program interrupt calls because each type of call returns to a different position when the interrupt program is complete. Interrupt programs allow for execution of another program while the interrupted program waits. When the sub program or macro program completes, execution picks up in the main program where it previously left off.

This article has solved no problems, not given the answer to questions you may have or typed out any sample programs. It was merely written to open your eyes to the possibilities. Every machining process is different and special attention to your particular case needs to be studied to arrive at a custom fit process. There are many obstacles to overcome if you are starting from scratch. I would suggest getting some experienced engineering help.