Servosila-Device-Reference-0xA020192

Command - Electronic Torque Control (ETC)
This commands instructs the controller to drive a brushless motor in such a way that the motor generates a specific
constant torque. Use this command to directly control torque of a brushless motor. Note that the command might cause
the motor to continuously accelerate.
Under the hood the controller converts the torque reference into an electrical current reference, and issues itself a "Field
Oriented Control (FOC)" command. Properly set the "Back-Emf Constant (Ke)" and "Poles Number" parameters in the
"Datasheet" section before using this command since the parameters are needed when converting the torque reference
to an electrical current reference.
Parameter Units Description Data type
Position in
Payload
1
Torque N*m The "Torque" parameter is the constant torque that the brushless
motor is commanded to produce.
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The RPDO COB-ID is 0x200.
The Command Code is 0x14.
This command should be sent CONTINUOUSLY at regular intervals to avoid heartbeat timeout on the device side.
Command - Direct Field Control: Rotation
The "Direct Field Control: Rotation" command instructs the controller to use the coils of a brushless motor to create a
magnetic field inside the motor, and then ROTATE the magnetic field with a given speed. What happens next is that
permanent magnets of the rotor get attracted to the rotating magnetic field of the coils. The rotor starts following the
rotation of the magnetic field. Note that this way of moving the rotor is inefficient from energy point of view as
compared to Field Orieted Control (FOC), and can lead to heating the motor. However this mode of operation is useful
any many practical applications such as gyro-stabilization of optical payloads.
Parameter Units Description Data type
Position
in
Payload
1 Voltage V This parameter specifies a voltage that the controller applies to the coils of
the stator to create a magnetic field inside the motor. The higher the
voltage is, the stronger the electric current in the coils is, the stronger the
rotor is attracted to the rotating magnetic field.
ATTENTION: Wrong voltage burns brushless motors. The coils of
brushless motors tend to have low electrical resistance. Even a small
voltage (0.20-0.30 V) can create an electric current strong enough to burn
the coils. If you are not sure what a safe voltage is, start with a small
voltage (0.10 V), and gradually raise it, while observing electrical currents
flowing through the motor's phases using the controller's telemetry screen.
The electrical currents should not be stronger than "Maximum Continuous
Current" limit of the motor, a datasheet value.
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