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 a Part that will become the Pulley

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

The rotating-Part may be:

or

STEP 4: Do Add 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 no limit to the number of DriveN Pulleys in one sketch-loop.

Kinematics Tree and the Pulley-Rocker

MD-17-1-KinematicsTreePulley

Kinematics of Pulley-Rocker

The complete kinematic-chain is the:

1.Rocker
2.Pulley-Rocker
oPart, with a
oPin-Joint, and a
oPath-Joint.

Tutorial and Reference Help Files for MechDesigner and MotionDesigner 13.2 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd