Introduction to TalonFX Control#
The TalonFX has a variety of open-loop and closed-loop control requests and supports Field Oriented Control.
Control Output Types#
The TalonFX currently supports three base control output types: DutyCycle, Voltage, and TorqueCurrentFOC.
Note
There are various configuration options available that influence the onboard control (for example, see Improving Performance with Current Limits).
DutyCycle#
A DutyCycle control request outputs a proportion of the supply voltage, which typically ranges from -1.0 to 1.0, inclusive. This control output type is typically used in systems where it is important to be capable of running at the maximum speed possible, such as in a typical robot drivetrain.
Voltage#
A Voltage control request directly controls the output voltage of the motor. The output voltage is capped by the supply voltage to the device. Since the output of a Voltage control request is typically unaffected by the supply voltage, this control output type results in more stable and reproducible behavior than a DutyCycle control request.
TorqueCurrentFOC#
Important
This feature requires the device to be Pro licensed.
A TorqueCurrentFOC control request uses Field Oriented Control to directly control the output torque current of the motor. Unlike the other control output types, where output roughly controls the velocity of the motor, a TorqueCurrentFOC request directly controls the acceleration of the motor.
Field Oriented Control#
Important
This feature requires the device to be Pro licensed.
Field Oriented Control (FOC) is a commutation mode that increases peak power by ~15%. All control modes that optionally support FOC have an EnableFOC field (Java, C++, Python). There are also control types that require FOC, such as TorqueCurrentFOC.
Behavior While Unlicensed#
When controlling an unlicensed device, the device will automatically fall back to non-FOC commutation for control requests that support the EnableFOC field.
For control requests that require FOC, such as TorqueCurrentFOC, the unlicensed device will:
Disable control output