Servo motor (servo motor) refers to the engine that controls the operation of mechanical components in the servo system. It is an auxiliary motor indirect transmission.
The servo motor can control the speed and position accuracy. It can convert the voltage signal into torque and speed to drive the control object.
The rotor speed of the servo motor is controlled by the input signal and can respond quickly. In the automatic control system, it is used as an executive element. Converted into
angular displacement or angular velocity output on the motor shaft.
What I share with you today is the debugging method of the servo motor.
1 initialization parameters
Before wiring, initialize the parameters.
On the control card: select the control method; clear the PID parameters; let the control card turn off the default enable signal when the control card is powered on; save
this state to ensure that the control card will be in this state when it is powered on again.
On the servo motor: set the control mode; set the enable to be controlled externally; the gear ratio of the encoder signal output; set the proportional relationship between
the control signal and the motor speed. In general, it is recommended that the maximum design speed in servo operation corresponds to a control voltage of 9V.
2 Wiring
Power off the control card and connect the signal line between the control card and the servo. The following lines must be connected: the analog output line of the control
card, the enable signal line, and the encoder signal line of the servo output.
After checking that there are no errors in wiring, power on the servo motor and control card (and PC). At this time, the motor should not move and can be easily rotated
by external force. If not, check the setting and wiring of the enable signal. Use external force to rotate the motor and check whether the control card can correctly detect
the change in motor position, otherwise check the wiring and setting of the encoder signal.
3 Test direction
For a closed-loop control system, if the direction of the feedback signal is incorrect, the consequences must be catastrophic. Turn on the servo enable signal through the
control card. This is the servo should rotate at a lower speed, this is the legendary "zero drift".
Generally, there are instructions or parameters on the control card to suppress zero drift. Use this command or parameter to see if the speed and direction of the motor
can be controlled by this command (parameter).
If it cannot be controlled, check the parameter settings of the analog wiring and control mode. Make sure that if a positive number is given, the motor is running forward,
and the encoder count is increased; if a negative number is given, the motor is running in reverse, and the encoder count is decreased.
If the motor has a load and the stroke is limited, do not use this method. Do not give too much voltage to the test, it is recommended to be below 1V. If the directions
are not consistent, you can modify the parameters on the control card or motor to make them consistent.
4 Suppression of zero drift
In the closed-loop control process, the existence of zero drift will have a certain effect on the control effect, it is best to suppress it. Use the control card or servo to
suppress the zero drift parameters, and adjust carefully to make the speed of the motor approach zero. Because the zero drift itself also has a certain randomness, it is not
necessary to require that the motor speed be absolutely zero.
5 Establishing closed-loop control
Release the servo enable signal through the control card again, and input a small proportional gain on the control card. As for how large it is, it can only be felt. If you are not
at ease, enter the minimum allowable amount of the control card Value, the control card and servo enable signals are turned on. At this point, the motor should already be
able to make a rough move in accordance with the motion command.
6 Adjust closed-loop parameters
Fine-tuning the control parameters to ensure that the motor moves according to the instructions of the control card. This is a work that must be done, and this part of the
work is more experience, which can only be omitted here.