Jogging at a certain angle (lathe mode)?

Hi,

I wonder is it possible to jog at a certain angle with linuxcnc in lathe mode?
That would be a nice feature in order to avoid the compound on a cross slide for prototyping.

I guess the pendant signals would have to go through some user comp which would re-calculates the absolute coordinates.
Did anyone do some work in that area already?

it should be fairly easy to implement I think, calculating cos and sine at a particular angle and forwarding the adjusted values

This might be helpful for study.
github.com/LinuxCNC/linuxcnc/blob/master...c/motion/simple_tp.c
github.com/LinuxCNC/linuxcnc/blob/master/src/emc/motion/axis.c

well simple_tp does single axis jogging only, so one option would be to inject the jog data into the trajectory planner command path eg. by using tpAddLine and setting the motion_state to EMCMOT_MOTION_COORD.

I still don't have enough overview about that linuxcnc code, but so far jogging at a certain angle works for me (I use 45° hardcoded at the moment).

X/Z of the pendant should be used for regular jogging
A/B for simulated cross-slide moves (A jog distance, B jog angle)

I still have some problems syncing the keyboard jog position with the pendant jog position but I guess I'll figure that out today.

MRx wrote:

X/Z of the pendant should be used for regular jogging
A/B for simulated cross-slide moves (A jog distance, B jog angle)

This is a neat idea, I like it!

Perhaps you could write a hal component to set the axis.L.jog-scale(s) according to the required angle? So if your overall jog scale is set to 0.1 mm/count for instance, and your angle is set to 30°, the component would set axis.z.jog-scale to 0.1×sin(30) and axis.x.jog-scale to 0.1×cos(30).

The component could easily be made to have its own "count" input pin for setting the required angle. Not sure how to display the set angle though, I guess using a custom gladeVCP panel?

(Trying to modify the motion code or motion planner to do this seems a bit heavy-handed IMO... and not easy to get right!)

The problem there is the jogs are not coordinated - particularity if they have different acceleration rates.

Wold we need a multi axis simpe tp ?

Maybe just adapt the existing infrastructure and re-use MOTION_COORD (that was my initial approach and worked to some degree ..)

Simple_TP serves its purpose well / independent Axis jogging. Possibly feeding simple_tp with correct parameters should work too (eg. use the slowest axis acceleration as reference instead of independent parameters).
Using simple_tp was my first approach but resulted in a jerky movement at that time I did not check for using common acceleration parameters.