General Procedure to add the Belt and Pulley Elements

Step 1: Add the Belt-Path:

Edit a Part, and sketch a sketch-loop with Lines and Arcs. The sketch-loop will become the path of the Belt.

Make sure you add a dimension to each Arc. Also, it is best to make the sketch fully constrained [the sketch should be black]

Step 2: Add a Motion-Point to the Belt-Path.

Use 'Add Motion-Path FB' and select the sketch-loop. This adds a Motion-Point to the 'Belt'.

The Motion-Point indicates the motion of the Belt.

Step 3: Add the Pulley Part:

Add a rotating-Part, with a Pin-Joint at the centre-Point of an Arc in the sketch-loop. The rotating-Part becomes a Pulley.

The rotating-Part may be:


Step 4: Add the Pulley:

Use Add Pulley [see the Command-Manager to select the correct elements].

If the rotating-Part [Step 3] is a kinematically-defined Part:
othe Motion-Point [on the Belt] becomes driven by the motion of the rotating-Part.
oThe rotating-Part becomes a DriveR Pulley.
oThe default colour of a Driver Pulley is Cyan.
oThere is a maximum of ONE DriveR Pulley in one belt/sketch-loop.

- or -

If the rotating-Part [Step 3] is not a kinematically-defined Part:
othe rotating-Part becomes driven by the motion of the Motion-Point on the Belt.
oThe rotating-Part becomes a DriveN Pulley.
oThe default colour of a DriveN Pulley is Magenta.
oThere is not a limit to the number of DriveN Pulleys in one sketch-loop.

tog_minus        Kinematics Tree and the Pulley-Rocker


Kinematics of Pulley-Rocker

The complete kinematic-chain is the:


It is a Part with a Pin-Joint and a Path-Joint.

The Path-Joint shows when you use Add Pulley.

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