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# Dialog: Servo-motor and Gearbox Sizing

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# Dialog: Servo-motor and Gearbox Sizing

## Kinetostatic Torque and Speed

Note: The options for a Linear Motor with a Slide-Joint will become available in a later release.

Use the Kinetostatic Torque and Speed dialog to:

Select a Planetary Gearbox from the major gearbox manufacturers

Select a Servo-motor from the major manufactures

Plot the Servo-motor Torque and Speed curve; in four quadrants, find the Maximum and RMS Torque values

Calculate the Duty-Cycle as a percentage of the machine-cycle

Note: Use this tool with one degree-of-freedom kinematic-chains. Email PSMotion if the kinematic-chain has two or more degrees-of-freedom, each with a servo-motor.

 How to open the Kinetostatic-Torque and Speed dialog
 STEP 1: Enable: You must be able to see the Motor-Symbol at a joint - see image below. A Motor Symbol is at the Pin-Joint that is a Power Source. STEP 2: Move the Power Source to the correct joint STEP 3: Open the Kinetostatic Torque-Speed dialog: 1.Click the Motor Symbol in the graphic-area The Pin-Joint shows in the Selection-Window. 2.Right-Click the Pin-Joint 3.Click Edit element in the shortcut menu. OR The Kinetostatic Torque-Speed dialog is now open.
 Application (Load) Torque vs Speed plot
 STEP 1: Auto-Filter and Range-Factor
 STEP 2: Select a Gearbox Manufacturer
 STEP 3: Select a Gearbox Model
 Gearbox Parameters Check List.
 Gearbox Output Torque vs Speed plot
 STEP 4: Select a Servo-motor Manufacturer
 STEP 5: Select a Servo-motor Model
 Servo-motor Parameters Check List.
 Servomotor Torque vs Speed plot

 Why is the Motor Torque is different to the Mechanism Torque
 More on Torque vs Speed Curves
 How we calculate the Motor Torque and Motor Speed