Jansen's linkage

[1] Jansen has used his mechanism in a variety of kinetic sculptures which are known as Strandbeesten (Dutch for "beach beasts").

Jansen's linkage bears artistic as well as mechanical merit for its simulation of organic walking motion using a simple rotary input.

All other links and pin joints are unactuated and move because of the motion imparted by the crank.

Their positions and orientations are uniquely defined by specifying the crank angle and hence the mechanism has only one degree of freedom (1-DoF).

[6] These models can be used to rate the actuator torque and in design of the hardware and controller for such a system.

Theo Jansen's linkage. When the blue line at the right end of the picture is driven in a clockwise rotary motion, the leg (blue triangle at the bottom) executes a walking motion. Relative (dimensionless) proportions shown.
Jansens' Strandbeest
Theo Jansen 's kinetic sculpture Strandbeest. A wind-driven walking machine.
A Strandbeest in action