How to measure torque of servo motor

Dear Experts,
i want to plot a speed torque characterstics in labview using ni hardware with servo motor.
please suggest me complete solution for this  above question

Torque specifications should be available from the motor manufacturer.  I'm not aware of a standard way to measure torque vs. speed, but maybe a google search would turn something up.  Here's what I found.
Good Luck
Adam

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