The Klann linkage is a planar mechanism designed to simulate the gait of legged animal and function as a wheel replacement. The linkage consists of the frame, a crank, two grounded rockers, and two couplers all connected by pivot joints.
The proportions of each of the links in the mechanism are defined to optimize the linearity of the foot for one-half of the rotation of the crank. The remaining rotation of the crank allows the foot to be raised to a predetermined height before returning to the starting position and repeating the cycle. Two of these linkages coupled together at the crank and one-half cycle out of phase with each other will allow the frame of a vehicle to travel parallel to the ground.
The Klann linkage provides many of the benefits of more advanced walking vehicles without some of their limitations. It can step over curbs, climb stairs, or travel into areas that are currently not accessible with wheels but does not require microprocessor control or multitudes of actuator mechanisms. It fits into the technological space between these walking devices and axle-driven wheels.
In US Patent 6,260,862 there is a set of coordinates for an example leg:
|9||1.366||1.366||first rocker arm axle|
|11||1.009||0.574||second rocker arm axle|
|fully extended ground stride position|
|grounded gait position|
The Klann linkage was developed by Joe Klann in 1994 as an expansion of Burmester curves which are used to develop four-bar double-rocker linkages such as harbor crane booms. It is categorized as a modified Stephenson type III kinematic chain.
- U.S. Provisional Application Ser. No. 60/074,425, was filed on Feb. 11, 1998
- US Patent 6,260,862, issued July 17, 2001
- US Patent 6,364,040, issued April 2, 2002
- US Patent 6,478,314, issued November 12, 2002
- Rooney, T., Pearson, M., Welsby, J., Horsfield, I., Sewell, R. and Dogramadzi, S. (6–8 September 2011), Artificial active whiskers for guiding underwater autonomous walking robots (PDF), CLAWAR 2011, Paris, France
- Enable Text, linkage design notes.
- U.S. Patent 6,260,862
- U.S. Patent 6,364,040
- U.S. Patent 6,478,314
|Wikimedia Commons has media related to Klann linkages.|
- Klann Linkage In Phun on YouTube Animation of the linkage's climbing ability
- Legs, mk2 on YouTube Clear side-on view of linkage in motion
- Son of Mr Crabby - CamBam made Klann linkage walking crab robot on YouTube
- Mondo Spider
- Walking Beast
- Artificial Active Whiskers for Guiding Underwater Autonomous Walking Robots eprint