Animations of linkage movement.

Ballistic Function

Mechanization of the ballistic function

This Stephenson III six-bar linkage sets the elevation of a ballistic trajectory to reach a specified distance downrange given an initial velocity of 500 m/s. This function is described in Computing Linkages by A. Svoboda (pg 285). Mark Plecnik obtained this linkage after evaluating almost 100,000 different designs.

Retractable handle

Retractable handle

This six-bar linkage was developed at the request of a designer who wanted the handle to move in and out along a circle, while the linkage and attachments were located in the rectangle. This linkage designed by Kaustubh Sonawale seems to meet his needs.

Tensegrity Linkage

Tensegrity Linkage

This is a design concept that uses tensegrity beam elements as the bars of a large-scale linkage system for use in deployable structures for disaster relief. This animation is by Mark Plecnik.

Kempe Linkages

Translational Linkages from Kempe

These linkages guide a platform in straight-line translation. They are generalizations of traditional straight-line linkages and can be found in Kempe’s How to Draw a Straight Line. Mark Plecnik generated the SolidWorks files and animations to help my MAE 183 students.


Kassim Car Door

An RSSR-TS Car Door Linkage

Kassim Abdul-Sater provides this CATIA animation of a spatial linkage that guides a car door through a spatial movement. This is a spatial RSSR four-bar linkage that connects the SS coupler to ground using a TS chain to control its orientation. He reports that this application was inspired by Kaustubh Sonawale’s spherical Watt I car door linkage.


Spherical Car Door Linkage

Spherical Watt I six-bar up close

This view shows the operation of the spherical Watt I six-bar door linkage designed by Kaustubh Sonawale.


Spherical Car Door

Spherical Watt I six-bar linkage

The movement of this car door is guided by a spherical Watt I six-bar linkage. This is a test of our prototype MechGen 5 design system. This will be the first design system for these linkages and is a another example of the work by Kaustubh Sonawale and Alex Arredondo.


Six-bar Function Generator

Stephenson II six-bar linkage function generator

Mark Plecnik designed this Stephenson II function generator by specifying eight accuracy points and solving the resulting 22 polynomial equations using the numerical homotopy solver, Bertini. He then used Mathematica to examine the 68,000 roots to find 38 useful linkages. SolidWorks was used to generate the solid model and animate the design.


Plecnik Art

Mark Plecnik’s Art Project

Mark Plecnik designed this system to illustrate the movement of a wide range of specialized linkages and gear trains.


Cameron Turner’s Wheelbarrow Linkage

Cameron Turner’s Wheelbarrow Linkage

Cameron Turner designed a four-bar and a six-bar linkage to assist the dumping movement of a wheelbarrow. This video provides a comparison of their operation.