phoenix6.controls.torque_current_foc#

Module Contents#

class phoenix6.controls.torque_current_foc.TorqueCurrentFOC(output: phoenix6.units.ampere, max_abs_duty_cycle: float = 1.0, deadband: phoenix6.units.ampere = 0.0, override_coast_dur_neutral: bool = False, limit_forward_motion: bool = False, limit_reverse_motion: bool = False)#

Requires Phoenix Pro; Request a specified motor current (field oriented control).

This control request will drive the motor to the requested motor (stator) current value. This leverages field oriented control (FOC), which means greater peak power than what is documented. This scales to torque based on Motor’s kT constant.

Parameters:
  • output (ampere) – Amount of motor current in Amperes

  • max_abs_duty_cycle (float) – The maximum absolute motor output that can be applied, which effectively limits the velocity. For example, 0.50 means no more than 50% output in either direction. This is useful for preventing the motor from spinning to its terminal velocity when there is no external torque applied unto the rotor. Note this is absolute maximum, so the value should be between zero and one.

  • deadband (ampere) – Deadband in Amperes. If torque request is within deadband, the bridge output is neutral. If deadband is set to zero then there is effectively no deadband. Note if deadband is zero, a free spinning motor will spin for quite a while as the firmware attempts to hold the motor’s bemf. If user expects motor to cease spinning quickly with a demand of zero, we recommend a deadband of one Ampere. This value will be converted to an integral value of amps.

  • override_coast_dur_neutral (bool) – Set to true to coast the rotor when output is zero (or within deadband). Set to false to use the NeutralMode configuration setting (default). This flag exists to provide the fundamental behavior of this control when output is zero, which is to provide 0A (zero torque).

  • limit_forward_motion (bool) – Set to true to force forward limiting. This allows users to use other limit switch sensors connected to robot controller. This also allows use of active sensors that require external power.

  • limit_reverse_motion (bool) – Set to true to force reverse limiting. This allows users to use other limit switch sensors connected to robot controller. This also allows use of active sensors that require external power.

property name: str#

Gets the name of this control request.

Returns:

Name of the control request

Return type:

str

property control_info: dict#

Gets information about this control request.

Returns:

Dictonary of control parameter names and corresponding applied values

Return type:

dict

output#

Amount of motor current in Amperes

max_abs_duty_cycle#

The maximum absolute motor output that can be applied, which effectively limits the velocity. For example, 0.50 means no more than 50% output in either direction. This is useful for preventing the motor from spinning to its terminal velocity when there is no external torque applied unto the rotor. Note this is absolute maximum, so the value should be between zero and one.

deadband#

Deadband in Amperes. If torque request is within deadband, the bridge output is neutral. If deadband is set to zero then there is effectively no deadband. Note if deadband is zero, a free spinning motor will spin for quite a while as the firmware attempts to hold the motor’s bemf. If user expects motor to cease spinning quickly with a demand of zero, we recommend a deadband of one Ampere. This value will be converted to an integral value of amps.

override_coast_dur_neutral#

Set to true to coast the rotor when output is zero (or within deadband). Set to false to use the NeutralMode configuration setting (default). This flag exists to provide the fundamental behavior of this control when output is zero, which is to provide 0A (zero torque).

limit_forward_motion#

Set to true to force forward limiting. This allows users to use other limit switch sensors connected to robot controller. This also allows use of active sensors that require external power.

limit_reverse_motion#

Set to true to force reverse limiting. This allows users to use other limit switch sensors connected to robot controller. This also allows use of active sensors that require external power.

with_output(new_output: phoenix6.units.ampere) TorqueCurrentFOC#

Modifies this Control Request’s output parameter and returns itself for method-chaining and easier to use request API.

Amount of motor current in Amperes

Parameters:

new_output (ampere) – Parameter to modify

Returns:

Itself

Return type:

TorqueCurrentFOC

with_max_abs_duty_cycle(new_max_abs_duty_cycle: float) TorqueCurrentFOC#

Modifies this Control Request’s max_abs_duty_cycle parameter and returns itself for method-chaining and easier to use request API.

The maximum absolute motor output that can be applied, which effectively limits the velocity. For example, 0.50 means no more than 50% output in either direction. This is useful for preventing the motor from spinning to its terminal velocity when there is no external torque applied unto the rotor. Note this is absolute maximum, so the value should be between zero and one.

Parameters:

new_max_abs_duty_cycle (float) – Parameter to modify

Returns:

Itself

Return type:

TorqueCurrentFOC

with_deadband(new_deadband: phoenix6.units.ampere) TorqueCurrentFOC#

Modifies this Control Request’s deadband parameter and returns itself for method-chaining and easier to use request API.

Deadband in Amperes. If torque request is within deadband, the bridge output is neutral. If deadband is set to zero then there is effectively no deadband. Note if deadband is zero, a free spinning motor will spin for quite a while as the firmware attempts to hold the motor’s bemf. If user expects motor to cease spinning quickly with a demand of zero, we recommend a deadband of one Ampere. This value will be converted to an integral value of amps.

Parameters:

new_deadband (ampere) – Parameter to modify

Returns:

Itself

Return type:

TorqueCurrentFOC

with_override_coast_dur_neutral(new_override_coast_dur_neutral: bool) TorqueCurrentFOC#

Modifies this Control Request’s override_coast_dur_neutral parameter and returns itself for method-chaining and easier to use request API.

Set to true to coast the rotor when output is zero (or within deadband). Set to false to use the NeutralMode configuration setting (default). This flag exists to provide the fundamental behavior of this control when output is zero, which is to provide 0A (zero torque).

Parameters:

new_override_coast_dur_neutral (bool) – Parameter to modify

Returns:

Itself

Return type:

TorqueCurrentFOC

with_limit_forward_motion(new_limit_forward_motion: bool) TorqueCurrentFOC#

Modifies this Control Request’s limit_forward_motion parameter and returns itself for method-chaining and easier to use request API.

Set to true to force forward limiting. This allows users to use other limit switch sensors connected to robot controller. This also allows use of active sensors that require external power.

Parameters:

new_limit_forward_motion (bool) – Parameter to modify

Returns:

Itself

Return type:

TorqueCurrentFOC

with_limit_reverse_motion(new_limit_reverse_motion: bool) TorqueCurrentFOC#

Modifies this Control Request’s limit_reverse_motion parameter and returns itself for method-chaining and easier to use request API.

Set to true to force reverse limiting. This allows users to use other limit switch sensors connected to robot controller. This also allows use of active sensors that require external power.

Parameters:

new_limit_reverse_motion (bool) – Parameter to modify

Returns:

Itself

Return type:

TorqueCurrentFOC

with_update_freq_hz(new_update_freq_hz: phoenix6.units.hertz) TorqueCurrentFOC#

Sets the period at which this control will update at. This is designated in Hertz, with a minimum of 20 Hz (every 50 ms) and a maximum of 1000 Hz (every 1 ms).

If this field is set to 0 Hz, the control request will be sent immediately as a one-shot frame. This may be useful for advanced applications that require outputs to be synchronized with data acquisition. In this case, we recommend not exceeding 50 ms between control calls.

Parameters:

new_update_freq_hz (hertz) – Parameter to modify

Returns:

Itself

Return type:

TorqueCurrentFOC