A Chain-Link rotates as it moves around each Pulley. Currently, we do not have a Part that rotates.
We can add a rotating-Part that makes a kinematic-link between the two Slider Sets.
The Chain-Link is represented by one of the two Parts in an R-P-R Dyad.
As always, a Dyad has two Parts and three Joints.
•Add a new Part - add a Pin-Joint (R--). Join it to a Point on Y-Slider of Slider-Set 1
•Add a new Part - add a Pin-Joint (--R). Join a Point on Y-Slider of Slider-Set 2
•Add a Slide-Joint (-P-) - between the CAD-Lines in each of the two new Parts
The two Parts and three Joints make the R-P-R Dyad.
We add a rotating-Part at each end of the Chain to represent the Pulleys
They must rotate (12÷5) times each time the Chain cycles one time.
Remember, Dyads always have two Parts and three Joints.
Add an R-P-R Dyad between Slider-Set 1 and Slider-Set 2
This dyad is: R(Pin-Joint) - P(Slide-Joint) - R(Pin-Joint)
Top-Tip: Temporarily hide the Motion-Dimension FBs. See Display Filters: Hide Dimensions
STEP 1: Add two Parts and R Joints
The two Pin-Joints are the Revolute joints in the R – P – R dyad.
STEP 1: Add a Slide-Joint to join the Part 1 and Part 2
The Slide-Joint completes the RPR Dyad.
The Part-Outlines of the Part 1 and Part 2 become Green.
When you cycle the machine, you will see the RPR Dyad move with the Slider-Sets.
STEP 2: Add a Measurement FB between the Pin-Joints
As you cycle the model you will see the length variation between the Pin-Joints is from 100mm to 93.55mm.
STEP 1: Add rotating-Parts for the Pulleys
STEP 2: Rotate the Pulleys at the correct Speed
The Chain - with 12 links - makes one full belt-length in each machine-cycle. Each Pulley has 5 Teeth for Chain-Links.
We can use the Gearing FB to change the rotational speed of the Pulleys. The ratio is #12/5 × Pulley Rotations per 1 Belt Path of 12 Links