﻿ Getting Started Tutorials - MechDesigner > Tutorial 17: Belts and Pulleys > Option 1: Fixed Pulley Centres > Multiple-Pulleys driven by one Pulley

# Multiple-Pulleys driven by one Pulley

### Fixed-Center Pulleys

We will add a Multi-Pulley and Belt system.

We can define the motion of ZERO or ONE Pulley. In this model we will define the motion of ONE Pulley. THe motion of the others are found from the velocity of the Belt.

We will edit the Number of Teeth on each Pulley

We will edit the Length of the Belt with Controlling Dimension, using the Target Belt Length parameter.

Preparation

 STEP 1: Add a closed sketch-chain (sketch-loop) to represent the Path of the Belt a)Edit the Base-Part b)Part-Editor: Add a sketch-loop with more than two Arcs c)Part-Editor: You MUST add a dimension to each Arc. The exact radius of the Arc is not important. The Belt will be Driven by a Driving-Pulley, which will be a Rocker d)Part-Editor: Add a Line - its start-Point is merged or coincident with the center-point of an Arc. e)Close the Part-Editor STEP 2: Add Motion-Path FB   Select the sketch-loop that represents the path of the belt. The Motion-Point shows at the start-Point of the sketch-element you select in the sketch-loop. STEP 3: Add a Rotating-Part for each Pulley. Add one rotating-Part with its Pin-Joint at the centre of each Pulley. The length of each Part is not important. STEP 9: Add a Motion-Dimension FB to the Part you wish to be the Driving-Pulley. A maximum of one kinematically-defined Part can be a Driving-Pulley.