Post by thread:measuring current pulses to imply torque

> I'd like to use a PIC to measure the torque on an R/C servo. For my > project, it would suffice to measure the pulse widths of current sent to the > motor by the h-bridge in the servo. Note that this is a rather poor approximation to torque. It does not take the motor back EMF into account, nor the flywheel current thru the diodes during the PWM off phase. You can compensate for these in software somewhat if you know the speed of the motor and the inductance of the motor coils. The latter can be measured once for the type of motor, but the former would have to be measured on the fly. ***************************************************************** Embed Inc, embedded system specialists in Littleton Massachusetts (978) 742-9014, http://www.embedinc.com -- http://www.piclist.com hint: To leave the PICList spam_OUTpiclist-unsubscribe-requestTakeThisOuTmitvma.mit.edu>