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Hello once again,

I have now changed the FERROR and MIN_FERROR values so that they are the correct way round. I have also reduced the acceleration and made the values the same in the ini and hal files.

The machine will function correctly without giving any joint follow errors in joint mode, in MDI mode and it will excecute programs correctly without any problems but I am still unable to jog in world mode as I get joint follow errors if I try and move anything other than very very slowly.

My current config is attached.

Thanks again,

Chris

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This all seems a bit odd, I will try to have a play with your config in a simulator tonight. (No promises though)

I couldn't use a simulator, I needed to try it on the real 5i25/7i76 machine. (luckily, I have one).

I made the problem go away by setting the stepgen maxaccel parameters to 0 in the HAL file.
However I seem to recall PCW saying that that was a bad idea.

It is, anyway, a bad idea in this case because the underlying problem is that there is _no_ acceleration limit applied when jogging in your config.
I am not sure why that would be, as there definitely is in a trivkins, and gantrykins is just a slightly complicated trivkins.

I think I fixed it

You need an entry in the [TRAJ] section of your INI file

[TRAJ]
...
DEFAULT_ACCELERATION = 20
...

Actually, all your accelerations seem a bit low really. Also, your stepgen-maxaccel values in the HAL file need to be 25% higher than the axis accelerations.

Andy is there something that needs to be in the manual about this?

I also don't see that entry in the gantry sample config... should it be there?

I also just tested the gantry config and it jogs fine in world mode so it there more to it than meets the eye? The only thing funny is the A axis shows up in world mode but does nothing it seems.

John

BigJohnT wrote:It is there in the INI config, but perhaps not stressed.I think so.Try sliding the speed slider to max and try again. It f-errors when you release the button.