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Why do servo motors hold their position?
It’s a function of the motor and the gearing in the servo. Typically the motor is geared down a lot in a servo, so the motor is spinning much faster than the servo output. That means the servo itself has a lot of torque, and torque translates to holding force.
How does a servo hold position?
A servo motor contains electronics that are internally turning a DC motor on and off as necessary to hold the target position. If the target does not match the current position, it turns on the motor to turn until the two match. The servo control loop is always running comparing the shaft position to a target.
How much current does a servo draw?
A standard servo will have a stall current around one amp, a micro servo will need a few hundred milliamps, and a giant servo can draw ten amps or more. Since servos run at basically the same voltages, the only ways servos can offer more torque is to have higher gear ratios or to use more current.
Why does the servo draw a high current when moving?
Current will be high again if a torque is applied to the servo arm this last can actually be higher than current while moving, up to the stall current of the internal DC motor. This is because the servo controller drives the motor hard to force it to hold the target position.
What do you need to know about a servo?
In a general sense, the servo is a control loop that takes as input a position target and applies force to hold at the requested target. If you want the target to be maintained, then the servo must be running. A servo motor contains electronics that are internally turning a DC motor on and off as necessary to hold the target position.
Where does a servo interpret a 1ms pulse?
A servo interprets a 1ms pulse as far left, a 1.5ms pulse as centre and a 2ms pulse as far right, usually. But what if there is no pulse?
What does CEMF do to a linear motor servo?
Although CEMF won’t prevent motion, it can help resist continued motion and provide instant deceleration when intermittent load spikes are applied that try to move the unpowered servo. All of the above is also generally true for linear motor servos.