Physical Properties Configuration

Swerve Module Physical Properties (modules/physicalproperties.json)

This JSON configures the physical properties shared with all the Swerve Modules. It maps 1:1 with PhysicalPropertiesJson which creates SwerveModulePhysicalCharacteristics.

Use the Standard Conversion Factors page to set the conversion factors for your robot if you're using a COTS swerve module!

Fields

Name	Units	Required	Description
conversionFactors	Conversion Factor Composition	Y	Conversion factor composition. Factor is calculated on startup.
optimalVoltage	Voltage	Y	Optimal voltage to compensate to and base feedforward calculations off of.
currentLimit	MotorConfig More info here.	N	The current limit in AMPs to apply to the motors. Stator limit for SparkMAXs, Supply limit for TalonFXs.
rampRate	MotorConfig	N	The minimum number of seconds to take for the motor to go from 0 to full throttle.
friction	MotorConfig	N	The minimum voltage to move the wheel or module. Defaults to 0.2 for drive motors, and 0.3 for angle motors.
robotMass	Lb (Pounds)	N	Default is 50kgs.
steerRotationalInertia	KilogramMetersSquare	N	The rotational inertia in KilogramMetersSquare . Defaults to 0.03.
wheelGripCoefficientOfFriction	Coefficient of Friction on Carpet	N	The grip tape coefficient of friction on carpet. Used to calculate the practical maximum acceleration.

MotorConfig

Name	Units	Required	Description
drive	Number	Y	Drive motor value.
angle	Number	Y	Angle motor value.

Conversion Factor Composition

Name	Units	Required	Description
drive	Drive Composition	Y	Drive conversion factor composition
angle	Angle Composition	Y	Angle conversion factor composition

Drive Conversion Factor Composition

Name	Units	Required	Description
diameter	Inches	Y	Diameter of the wheel.
gearRatio	Number	Y	Gear ratio of the drive motor to wheel.
factor	Number	N	Pre-calculated conversion factor.

Angle Conversion Factor Composition

Name	Units	Required	Description
gearRatio	Number	Y	Gear ratio of the angle/steering/azimuth motor to wheel.
factor	Number	N	Pre-calculated conversion factor.

Example Configuration File

{
  "conversionFactors": {
	"angle": {"gearRatio": 28.125},
	"drive": {"diameter": 4, "gearRatio": 6.75}
  },
  "currentLimit": {
    "drive": 40,
    "angle": 20
  },
  "rampRate": {
    "drive": 0.25,
    "angle": 0.25
  },
  "wheelGripCoefficientOfFriction": 1.19,
  "optimalVoltage": 12
}