Four-bar Kinematic-chains

Many more to come with time....

Four-bar: one Motion-Part, two Parts in a Dyad, and a total of four Joints.

The Motion-Part is a Rocker or Slider.

Crank +RRR


Four-bar Mechanism

Four-bar Linkage

Crank + RRP


Crank + RRP

Offset Slider Crank

Crank + RPR

Crank is Shorter than the Frame Part

Output is an rotating-part that swings back and forth - it is an Oscillating Output.

Crank + RPR

Crank is Longer than Frame Part

Output is a rotating-part.

Crank + RPR

Offset Slider

Crank + PRP

Output sliding-part moves between ± Infinity.

Crank + RPP

Output sliding-part moves with Simple Harmonic Motion.

Known as a 'Scotch -Yoke'


Crank + PRR

The RRP Dyad is Asymmetrical - you can think of it as an RRP or an PRR. The Dyad itself is identical, but you can reverse the two 'outer' joints: you can connect the R joint to the Crank or the P Joint to the Crank.

Reversed: You can connect the Prismatic-Joint to the Crank or the Ground

The input can only oscillate - it is a Rocker.

Oscillating Output. Output is shorter than fixed Part.

Crank + PRR (The Dyad is 'Reversed')

The input can rotate fully - it is a Crank.

The Prismatic Joint is along the Input 'Crank', not on the ground

Output Rotates

Crank + PRR (The Dyad is 'Reversed')

Rocker Output

The Prismatic-Joint is along the Input 'Crank', not on the ground

Output Rocker is longer than fixed Part




Slider RPR

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