<Hello everyone am studying Electrical/Electronics with City and guilds of London, they have a training center in Nigeria. I just rounded up level 3 and studying for level 5. i got wind of robotics while studying level 3 and since then been so facinated about it. i want to interact with experts lately am designing a CNC machine and am still stumbling over some interfacing, so i would like pointers.>


Hi Teme,

As there are several interfaces involved in a CNC machine, I am wondering which ones you are having your stumbling points over.


The CNC machine will typically have a machine bed where the work peice is bolted down to and two, three of four degrees (X/Y/Z/A) of motion (separate motorised axis).

You have interfaces between the motor and the X/Y/Z drive electronics which may be a stepper motor or servo motors with positional feedback. Each of these, because they are connecting to a motor, of some descroiption, will necessitate some power electronics to provide sufficent power to deal with moving masses. The tool motor (usually designated A) is quite often a variable speed motor that has a very high speed of rotation. Quite often these are brushless DC motors.


The other interfaces will be between your CNC machine controller and the indivdual power electronic modules that drive the motor systems. Finally, there is also the necessary interface between your CAD PC and the CNC controller.


Regarding software, most CNC machines (of the milling variety) use G-Codes or M-Codes. These instruct the CNC controller regarding the specifics of motion for teh tip of the tool and have to be translated into motion for each of the axis'. If you are implementing the CNC controller yourself, you should consider using these codes. See <www.cnccookbook.com/.../> for a list of both G-Codes and M-codes.


Of course, there are other ways of implementing a CNC machine. One could use a fixed tool head and a multi-axis robotic arm to move the work peice.


Happy to hold email conversations on the topic.


regards

Paul E. Bennett IEng MIET.

<Hello everyone am studying Electrical/Electronics with City and guilds of London, they have a training center in Nigeria. I just rounded up level 3 and studying for level 5. i got wind of robotics while studying level 3 and since then been so facinated about it. i want to interact with experts lately am designing a CNC machine and am still stumbling over some interfacing, so i would like pointers.>


Hi Teme,

As there are several interfaces involved in a CNC machine, I am wondering which ones you are having your stumbling points over.


The CNC machine will typically have a machine bed where the work peice is bolted down to and two, three of four degrees (X/Y/Z/A) of motion (separate motorised axis).

You have interfaces between the motor and the X/Y/Z drive electronics which may be a stepper motor or servo motors with positional feedback. Each of these, because they are connecting to a motor, of some descroiption, will necessitate some power electronics to provide sufficent power to deal with moving masses. The tool motor (usually designated A) is quite often a variable speed motor that has a very high speed of rotation. Quite often these are brushless DC motors.


The other interfaces will be between your CNC machine controller and the indivdual power electronic modules that drive the motor systems. Finally, there is also the necessary interface between your CAD PC and the CNC controller.


Regarding software, most CNC machines (of the milling variety) use G-Codes or M-Codes. These instruct the CNC controller regarding the specifics of motion for teh tip of the tool and have to be translated into motion for each of the axis'. If you are implementing the CNC controller yourself, you should consider using these codes. See <www.cnccookbook.com/.../> for a list of both G-Codes and M-codes.


Of course, there are other ways of implementing a CNC machine. One could use a fixed tool head and a multi-axis robotic arm to move the work peice.


Happy to hold email conversations on the topic.


regards

Paul E. Bennett IEng MIET.