Units

Default Units

Quantity	Default Units	Affected by
Setpoint	Rotations	Position Conversion Factor
Encoder Position	Rotations	Position Conversion Factor
Encoder Velocity	RPM	Velocity Conversion Factor
Applied Output	Duty Cycle
kP	Duty cycle per rotation	Position Conversion Factor
kI	Duty cycle per (rotation*ms)	Position Conversion Factor
kD	(Duty cycle*ms) per rotation	Position Conversion Factor
kS	Volts
kV	Volts per RPM	Velocity Conversion Factor
kA	Volts per RPM/s	Velocity Conversion Factor
kG	Volts
kCos	Volts per Rotation
MAXMotion Cruise Velocity	RPM	Velocity Conversion Factor
MAXMotion Maximum Acceleration	RPM/s	Velocity Conversion Factor
MAXMotion Allowed Profile Error	Rotations	Position Conversion Factor

Conversion Factors

There are two configurable Conversion Factors on each Encoder type that can be used to account for gear ratios and unit conversions in the motor control logic. These are applied independently and the velocity factor does not rely on the position factor, so different units can be used for each.

Position Conversion Factor

Positions read from the feedback encoder are multiplied by the Position Conversion Factor before being processed by the closed-loop controller.

Common Position Conversion Factors

Description	Factor
Default (Revolutions)	1
Degrees	360
Radians	2π (6.28318530718)
10:1 Gearbox, Rotations at output	1/10 (0.1)
Distance in inches traveled with a 6in diameter wheel	6π (18.8495559215)

Velocity Conversion Factor

Velocities read from the feedback encoder are multiplied by the Velocity Conversion Factor before being processed by the closed-loop controller.

The velocity conversion factor is completely independent of the position conversion factor, so both need to be set to change both units.

All accelerations on the SPARK controllers are in terms of velocity per second, where the velocity is in units specified by the Velocity Conversion Factor.

Common Velocity Conversion Factors

Description	Factor
Default (RPM)	1
Revolutions per Second	1/60 (0.01666666666)
Degrees per Minute	360
Degrees per Second	360/60 (6)
Radians per Minute	2π (6.28318530718)
Radians per Second	2π/60 (0.10471975512)