Create STAR.clld_probe_x_position_using_channel()

[BioCam]

Hi everyone,

In previous PRs I've added different object probing methods to the STARBackend class:

Z-Probing

• PR#69: Probe z height using channel (cLLD)
• PR260: Build ztouch Probing Function (force sensing)

Y-Probing

• PR#682: Probe y-position of resource using channel with cLLD

This PR

Here I am completing the series by adding X-Probing using cLLD:

  async def clld_probe_x_position_using_channel(
    self,
    channel_idx: int,  # 0-based indexing of channels!
    probing_direction: Literal["right", "left"],
    start_pos_search: Optional[float] = None,  # mm
    end_pos_search: Optional[float] = None,  # mm
    move_to_safe_z_before_move_to_start_pos: bool = True,
    post_detection_dist: float = 2.0,  # mm,
    tip_bottom_diameter: float = 1.2,  # mm
    read_timeout=240.0,  # seconds
  ) -> float

Warnings this STARBackend method...

• can ONLY be used to probe conductive materials (!),
• assumes you are using a Hamilton 1_000uL teaching needle for probing - if you use a different conductive tip, you have to modify the tip_bottom_diameter argument,
• should be used with caution - improper usage could break the channel.

Though, I've measured the default speed of this method to be 0.45 mm / second - so you have plenty of time to hit the emergency stop button if you e.g. accidentally made it probe a non-conductive material (e.g. a plate, tube, trough, ...).

Power
Together with z-probing and y-probing, x-probing now enables PyLabRobot programmers to make the STAR measure its own environment... and correct itself if something differs to the workcell model 👀

We are now deep in PLR's "autonomation" stage 🚀

Please let us know your thoughts, and whether you encounter any issues.

Happy automation 🦾

[Copilot]

Pull request overview

This PR introduces X-axis probing functionality using capacitive liquid level detection (cLLD) to complete the suite of object probing capabilities for the STAR robot system.

Key Changes:

• Adds clld_probe_x_position_using_channel() method to enable lateral X-axis probing of conductive materials
• Updates clld_probe_y_position_using_channel() to round return value to 1 decimal place for consistency

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[rickwierenga]

Completing the Trinity!!

[rickwierenga]

excellent