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Overview

The SPEED parameter group (specifically SPEED_MAX) configures the horizontal travel speed for ArduRover.

Key Concepts

1. Velocity Target

  • SPEED_MAX: The physical maximum speed (m/s) that the rover is capable of at full throttle.
  • Estimation: If set to 0, the autopilot will attempt to estimate the max speed based on CRUISE_SPEED and CRUISE_THROTTLE.

Developer Notes

  • Library: ArduRover/Parameters.cpp.
  • Related: Multicopter navigation speeds are typically in the WPNAV_ group.

SPEED_MAX

m/s
Default 0.0f
Range 0 30

Speed maximum (SPEED_MAX)

Description

This parameter defines the Physical Maximum Speed of the Rover at 100% throttle. The navigation controller uses this value to scale its throttle output. If set to 0, the autopilot will attempt to estimate it based on CRUISE_SPEED and CRUISE_THROTTLE, but setting it explicitly provides better performance.

The Mathematics

$$ \text{Throttle}\_{demand} \approx \frac{\text{Target Speed}}{\text{SPEED\_MAX}} $$

The Engineer's View

Defined in Rover/Parameters.cpp. Used in AR_AttitudeControl (the Ackermann/Skid steering controller) to normalize speed demands to throttle percentages.

  • If 0: SPEED_MAX is derived: $\text{SPEED\_MAX} = \text{CRUISE\_SPEED} / (\text{CRUISE\_THROTTLE} / 100) $.

Tuning & Behavior

  • Default Value: 0 (Auto-calculate)
  • Set to: The actual top speed of the rover in meters/second.
  • Effect: Improving this value helps the speed controller achieve target speeds more accurately without overshooting (if too low) or undershooting (if too high).
View Source

SPEED_TYPE

Default 0
Range 0 4

SPEED_TYPE: Wind speed sensor Type

Description

This parameter selects the type of hardware used to measure wind speed (anemometer) when using the WindVane library.

Values

Value Meaning
0 None (Disabled)
1 Analog Pin (Voltage-based anemometer)
2 Modern Device (I2C or Serial sensor)
4 SITL (Simulation only)
  • Default: 0

Description

SPEED_TYPE is used on autonomous sailboats and wind-monitoring systems to quantify the current wind velocity.

  • Function: Knowing the exact wind speed allows the autopilot to make better decisions about sail trim and tacking maneuvers.
  • Requirement: Once you select a type, you must also configure the corresponding hardware pins (e.g., WNDVN_SPEED_PIN) and scaling factors.
  • Usage: Primarily used in ArduRover (Sailboat) and specialized ground stations.
View Source
Specific Gravity Configuration (SPEC) Crop Sprayer Configuration (SPRAY)