Hello there, I am new to CNC programing and am facing a challenging task. Hope you can contribute/help.

My query is about interactions between “PROG RUN” and “MDI” modes.

Basically, I have written of sub-routine with lab-view for visiting points on a surface. The sub-routine enables to bring my tool holder (equipped with a camera) close to points of interest. In practice, this is done through a txt file that the CNC reads and executes in PROG RUN mode. As there is four points the CNC does it through four sequences. At the end of each sequence, the operator must handwheel the camera for fine adjusting the position. Then he captures the set of coordinates. Practically, the acquisition of coordinates is carried out by a four step explained hereafter. First there is a M0 in my sub-routine, operator select the handwheel mode, using electronic handwheel he fine tunes the position, he selects the MDI mode, he records the coordinates in the MDI mode, and he selects PROG RUN mode for executing the rest of the program. Indeed, he stores XYZ coordinates in MDI through the hard key “capture actual position”. This works fine till he goes back to PROG RUN mode. The reason is that the CNC needs that he pushes the “REST POS AT” soft key, push “RUN” button, push “RESTORE POSITION” soft key, push “RUN” button, push “RUN” button n times according to number of axes used for fine tuning. In other words, it is a quite demanding procedure for operators.

Camera is mounted solid into the toolholder. However at the end of this process I take camera out manually. The reason why I want to implement this routine is for safety. Indeed, prior to be ready for my machine, mirrors went through grinding, robot polishing (for months). Once mounted in my machine if operator comes to touch mirror with camera or the distance between ion beam source and mirror’s surface is not correct is money through the door.

For your information, instead of regular milling tool I use an ion gun in vacuum environment. It is a big pressure vessel with a motion system embeded. The machine is built for corrections of surfaces at atomic level (astronomy and space applications). The machine has five axes and algorithm is based on dwell time.

Any suggestions will help?

Additional information:
Brand: Heidenhain
Model: TNC430 (5 axes)
NC: Software number 280472 13
PLC: software number BASIC—31
SETUP: 280641 13