R-R-R Dyad

Dyads do not change the number of Degrees-of-Freedom of a kinematic-chain. If the kinematic-chain has Green Part-Outlines before you add the Dyad, it should have Green Part-Outlines after


To show you how to add this Dyad, we have two design cases.

In Case 1, we join the two Parts in the Dyad to the Base-Part and the Rocker
In Case 2, we join the two Parts in the Dyad to the Base-Part and the Slider

There are three Pin-Joints in the R-R-R Dyad, and two Parts.

I follow a consistent three-step procedure.

General Three-Step Procedure to add a Dyad

STEP 1: Add the two Parts
STEP 2: Add the two 'outer' Joints: Join each Part to two separate Kinematically Defined Parts
STEP 3: Add the 'inner' Joint: Join the two Parts together

CASE 1:
Rocker + R-R-R

CASE 2:
Slider + R-R-R

Examples

 

'Expand' then 'Play'

 

 

'Expand' then 'Play'

 

Videos

RRRrocker1

RRRSlider1

Preparation:

Two Kinematically Defined Parts:

Case 1: Part 1: Base-Part, Part 2: Rocker
Case 2: Part 1: Base-Part, Part 2: Slider

RRRrocker2

RRRSlider2

Step 1: New Parts

Add two parts to the Mechanism.

RRRrocker3

RRRSlider3

Step 2: 'Outer' Joints

Add the two 'outer' Joints (R-R-Joints). In this case, a

Pin-Joint with the new Part and the Motion Part Red-14-1b
Pin-Joint with the other new Part and the Base-Part Red-14-2

The two Joints are the 'outer' Joints of the R-R-R Dyad: R-R

RRR Dyad with Rocker

RRR Dyad with Sldier

Step 3: 'Inner' Joint

Connect the two new parts together with a Pin-JointRed-14-3

The Kinematic-Chain becomes Kinematically Defined with an R-R-R Dyad

Green Part-Outlines

RRRrocker5

RRRSlider5

Kinematics-Tree

Shows the original Rocker or Slider, plus the new R-R-R Dyad

Tutorials and Reference Help Files for MechDesigner and MotionDesigner 14.2 + © Machine, Cam, Mechanism, and Motion Design Software by PSMotion Ltd