Tag Archive for: compliant mechanisms

Lamina Emergent Mechanisms

BYU Professor Larry Howell studies lamina emergent mechanisms, in other words, machines that emerge from flat pieces of material. If you think about the subtly complex movement of a children’s pop-up book, the way a page elegantly untucks itself to display a scene and then tucks itself back in, you wouldn’t be too far off.  The interesting thing about lamina emergent mechanisms is that they are compliant mechanisms that come out of a plane—out of a flat surface—which allows for a low cost of manufacturing. The trick is that designing something like this is challenging, and indeed “design of lamina emergent mechanisms that have not previously been possible” is the big challenge this research pushes up against.

Lamina emergent mechanisms, or LEMs, can perform sophisticated tasks with simple topology. The cost efficiency of this type of mechanism starting from a flat initial state means that there is the potential for very affordable manufacturing.  Since these mechanisms “pop out” of flat materials, manufacturing them in large quantities is cost effective since the associated manufacturing processes for replicating sheet materials are relatively simple and therefore low cost.

lamina-emergent-mechanismsLamina emergent mechanisms are notable because they save space. They emerge from a flat initial state so they can be used in applications that have limited space, which is oftentimes a design challenge. From a business perspective, these mechanisms are attractive because they can be made compact for shipping and then later deployed in their designed function at the desired location when they need to be. Reductions in handling, shipping, and storing, particularly in high volume, can lead to significant cost savings.

lamina-emergent-mechanisms-interacting

Another thing to note is that these mechanisms can interact with one another in interesting, useful ways, as seen in this image. 

The word that comes to mind with lamina emergent mechanisms is efficiency. We’ve talked about efficiency in manufacturing, but now let’s talk about efficiency at the machine level. The creation of controlled motion without bearings leads to opportunities for increased precision because of the elimination of backlash and wear, reduction of friction between rubbing parts, and the lack of a need for assembly since the devices are single-piece constructions. There are a lot of wins with LEMs, which means they have a bright future.

A key to the continued advancement of LEMs and their applications is the development of actuation approaches to allow them to move. – BYU Compliant Mechanisms Research Website

Professor Craig Lusk (University of South Florida) works in the same field and designs shape shifting mechanisms that could be used for statically balanced body armor that could take the form of a collapsible shield or provide full body coverage.

Select here to see Professor Howell’s presentation on LEMs at the Workshop on 21st Century Kinematics.