Homing lift downward contact calibration?

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1

I noticed that the lift does not ever self-calibrate how low it can go, but it does calibrate how high the lift can go (and it marks those positions).

Are the downward limits hard-coded?

I am just curious about this, it isn’t blocking any work.

Separately, I am curious as to where files like stretch_xbox_controller_teleop.py are on github, because I couldn’t find them.

2

Hi. Indeed, the lift range of motion was calibrated at the factory. Nominal range is 1.1m.

This value can be found in your factory params (~/stretch_user/stretch-re1-xxx/stretch_re1_factory_params.py). For example:

lift:
  range_m:
  - 0.0
  - 1.0981830239156594

We don’t measure in the downward direction for two reasons:

  • To avoid inadvertent collisions if the user has an unknown payload attached to the wrist.
  • To decrease the time required to run the homing procedure

Also, stretch_xbox_controller_teleop.py is a part of the hello-robot-stretch-body-tools package, which is found here:

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