step.servo.preset

ServoPreset — named positions for a servo, generated from project YAML.

A ServoPreset wraps a raw Servo and provides callable attributes for each named position. It is the recommended way to interact with servos that have well-defined positions (e.g., “open”, “closed”, “up”, “down”).

Calling a position without speed uses an instant servo() command. Calling with speed uses SlowServo for eased motion.

The optional offset shifts all positions by a fixed amount — useful when a servo is remounted slightly off from its original alignment.

Instances are normally code-generated from raccoon.project.yml into defs.py, so users just import and call:

from src.hardware.defs import Defs

# In a mission sequence:
Defs.pom_arm.down()            # instant
Defs.pom_arm.up(speed=250)     # eased at 250 deg/s

YAML definition:

definitions:
  pom_arm:
    type: Servo
    port: 1
    offset: 0           # optional, default 0
    positions:
      down: 0
      above_pom: 50
      up: 90

Classes

ServoPreset

Named servo positions with optional mounting offset.

Module Contents

class step.servo.preset.ServoPreset(servo: raccoon.hal.Servo, positions: dict[str, float], offset: float = 0)

Named servo positions with optional mounting offset.

Each position becomes a callable attribute that returns a Step.

Parameters:

• servo – The underlying Servo hardware device.

• positions – Mapping of position name to angle in degrees.

• offset – Fixed angle offset added to every position (default 0).

property device: raccoon.hal.Servo

The underlying Servo hardware device, for raw access.

property offset: float

Current mounting offset in degrees.

property positions: dict[str, float]

Copy of the position name → angle mapping (before offset).