Mechanism Design and Mechanism Dynamics > Mechanism Dynamics > Other Measures > About Net Load Measures
About Net Load Measures
A net load measure evaluates the force applied by a motor, spring, damper, force, or torque, or the net force experienced by a motion axis. You can create this measure to determine whether the load exerted by one of these entities during an analysis meets your criteria for the mechanism. You can also use this measure to confirm a force motor profile or to confirm that a user-defined force or torque reaches the desired value at the desired time.
For example, assume you have defined a servo motor to reach a certain velocity in a certain amount of time, and you want to know how much force to apply to attain the same velocity in the same amount of time. You can run a dynamic analysis with the servo motor, create a net load measure that displays the force variation with time, and create a force motor with the same force profile.
You define a spring by specifying the unstretched length and a stiffness constant. You define a damper by specifying a damping coefficient. The actual forces felt by a spring or damper will be the result of other reactions present in the mechanism. In both cases, you can use a net load measure to calculate the force on the spring or damper during an analysis, and adjust your definitions to meet the needs of your mechanism.
* If your model includes a gear pair connection, the reaction measures on the connections used to create the gears will not include a contribution from gear tooth contact.
You can select the following entities for net load measures:
Servo motor—Measure the total load applied by the servo motor to cause the specified motion
Force motor—Measure the value of the force applied by the force motor.
Spring—Measure the applied value of the spring load.
Damper—Measure the applied value of the damper load.
Force/Torqu—e–Measure the applied value of the force or torque. Use this measure, for example, if you define a table force or user-defined force that varies with time, to confirm that the force reaches the desired value at a given time during the analysis.
Motion axis—Measure the sum of all the applied loads, including forces, motors, springs, and dampers, acting on the motion axis. This sum does not include forces, torques, or connection reactions.