Avoiding servo jitter

I tried using capacitors to avoid servo jitter and it worked.So should i use 4 capacitors for avoiding jitter for 4 servos.I am using breadboard and arduino uno.The capacitors are 470 uf 25v .

The best way to avoid servo jitter is to use an adequate power supply, capable of handling the total stall current of all the servos that are moving at once. The Arduino 5V output should never be used for motors or servos.

A power supply capable of providing one Ampere per servo is a good rule of thumb, but look up your servo's stall current to be sure. Be sure to connect all the grounds.

Breadboards will burn out if used as connections to motors and servos. It is best to solder all power connections.

Bume:
I tried using capacitors to avoid servo jitter and it worked.So should i use 4 capacitors for avoiding jitter for 4 servos.I am using breadboard and arduino uno.The capacitors are 470 uf 25v .

I don't see a question here.

Servo motors are never "off". When they reach a setpoint, the motor will constantly make micro-adjustments to stay in position. Cheaper servos with plastic gears are worse than expensive servos with metal gears and a higher gear ratio to the feedback variable resistor, but they all will do micro adjustments to maintain position as whatever the servo is driving drifts out of position.

I can't imagine where you would put a capacitor on a servo, let alone one that large.

Capacitors are sometimes placed across the power lines close to the servo in an attempt to help with the initial startup current surge. They rarely work well. But since to do anything at all they should be close to the servo then you would need four if one is going to be close to each servo.

But as already said (many times all over these forums) it would be far more effective just to use a better power source that can provide the required current without messing about adding capacitors.

Steve

@SteveMann can u post a source from where you got information about “micro adjustments
“ while servo is ON? Just for an experiment if you will send a signal to servo to move to some degree/angle then stop feeding with signal but still powering servo will it make adjustments to stay in position? I dont know the answer to my question but its interesting if its doing the way you described.

My statement assumes that the servo is still connected to the arduino. The PWM signals are still there and as the servo drifts, and they all do, it gets nudged back to the setpoint. This is what I am assuming that you mean by "servo jitter".

set your servo pin as input_pullup on start up

call

servo.attach(servo_pin);

your_move_function();

servo.detach();

surepic:
if you will send a signal to servo to move to some degree/angle then stop feeding with signal but still powering servo will it make adjustments to stay in position?

If by "stop feeding with signal" you mean do a servo.detach() then no, it won't "make adjustments to stay in position" since at that stage it has no notion of "position".

Hi,
If you wish your servo to stay in the position and you have it set by the input signal AND the servo is working against a torque load;

If you detach the signal the servo will loose control and the arm will move out of position because of the torque load.

You have to stay attached and sending the position signal, this means the servo motor will be keeping position by applying its own torque in STALLED mode.
So the servo will be consuming power even if it is not moving.

Tom.. :slight_smile: