CNC AXIS IN PARKING MODE

Good morning everyone.
I need to replace an old Siemens CNC.
I'd like to try Linux CNC, but the machine is a boring machine with a Z-axis that can be controlled manually or via CNC.
Let me explain. The Z-axis performs normal axis reference and moves in jog+ and jog- directions, with the position controlled by an optical scale.
However, the operator can press a mechanical selector, which allows the axis to be moved with a mechanical handwheel and, when desired, re-engage the axis in the CNC.
Clearly, the current CNC disables the axis drive when the mechanical handwheel is selected.
The axis on the current CNC goes into park mode, meaning the commanded position follows the feedback position, and when the mechanical handwheel is disengaged, the CNC does not enter a following error.
With Linux CNC, I could disable the drive and move the axis with the mechanical handwheel, but as soon as I disable the handwheel and enable the drive again, the CNC displays the following error because the commanded position doesn't follow the feedback position.

Is there a way to mimic the behavior of the Siemens CNC?

Thanks for support

A picture might help.

Why do you need to use a manual handwheel?

Wouldn't it be possible to move the axis solely via CNC control?

What is "The following error"? You don't print any error message after that statement.

An idea:
You could connect a rotary encoder wheel and configure LinuxCNC so it behaves exactly like the handwheel, but drives the axis via the motors and CNC, without directly, physically moving the axis itself. It'll also save your shoulder from the strain of turning the handwheel and allow ultra-precise movement too.

I'm sure that the functionality you describe is possible, but I'm sure there must be some easier workaround for this problem.

Just to come up with something, doesn't necessarily mean it is practical
- set f-error-limit to a lot
- get feedback position
- fast forward to feedback position (servo off)
- reset f-error-lim and re-engage the servo
Maybe this can be done in a g-code macro.

You should be able to create  component that sets feedback = commanded pos when the handwheel is engaged. the cia402 component does this...

Thanks for the replies.
The solution of increasing the tracking value and resetting the axis is impractical and technically incorrect.

The servos are analog and controlled by Mesa boards.
Isn't there a component that creates the command position = position read by the transducer?
Or is there a way to modify the Trivkins kinematics?

Why do you need to manaully move the axis?

Why does jogging the axis via LinuxCNC not suffice.

There is a myriad of configuration options available in the config files.

Isn't there a component that creates the command position = position read by the transducer?

LinuxCNC does this (sets commanded position to actual position) when motion is disabled, but it's global (all joints)
It might require a modification of LinuxCNCs motion component to do this correctly on a joint by joint basis

OP: Is this a one axis machine?

Try the attached component

Untested. Probably has some typos but the logic should be sound.

Ooops, I did not set  pos_cmd_out but its not needed and could be removed from the component