Urgent Servo Motor Problem

Hi i m doing a self balancing bipedal walking robot for my final year engineering project..I m using 6 servomotors from nex robotics.. the motors were working fine until recently.. They are giving jerky movements even for one stationary position command. i cant understand why?? Also i dunno how to measure the current drawn by the motors? Pls help me out

hi,
If you have access to a oscilloscope one method is to add a low value resistor in series with motor, [ low side] and measure the voltage waveform across the known value resistor, then use Ohms law to calculate the current.
The resistor value should be as low as possible in order not to limit the measured current, say 0.1R thru 0.5R

I would also check that your power supply is able to supply the current required in the 'worst case' demand by the motors.