(Nanowerk Information) Widespread push puppet toys within the shapes of animals and fashionable figures can transfer or collapse with the push of a button on the backside of the toys’ base. Now, a staff of UCLA engineers has created a brand new class of tunable dynamic materials that mimics the internal workings of push puppets, with purposes for smooth robotics, reconfigurable architectures and area engineering.
Inside a push puppet, there are connecting cords that, when pulled taught, will make the toy stand stiff. However by loosening these cords, the “limbs” of the toy will go limp. Utilizing the identical twine tension-based precept that controls a puppet, researchers have developed a brand new kind of metamaterial, a fabric engineered to own properties with promising superior capabilities.
The undeployed metamaterial (left) positive factors energy and type when deployed (heart), with the power to return to its limp state (proper). (Picture: Wenzhong Yan, UCLA)
Revealed in Supplies Horizons (“Self-deployable contracting-cord metamaterials with tunable mechanical properties”), the UCLA examine demonstrates the brand new light-weight metamaterial, which is outfitted with both motor-driven or self-actuating cords which are threaded via interlocking cone-tipped beads. When activated, the cords are pulled tight, inflicting the nesting chain of bead particles to jam and straighten right into a line, making the fabric flip stiff whereas sustaining its total construction.
The examine additionally unveiled the fabric’s versatile qualities that would result in its eventual incorporation into smooth robotics or different reconfigurable constructions:
The extent of stress within the cords can “tune” the ensuing construction’s stiffness — a completely taut state affords the strongest and stiffest stage, however incremental modifications within the cords’ stress permit the construction to flex whereas nonetheless providing energy. The secret is the precision geometry of the nesting cones and the friction between them.
Buildings that use the design can collapse and stiffen time and again, making them helpful for long-lasting designs that require repeated actions. The fabric additionally affords simpler transportation and storage when in its undeployed, limp state.
After deployment, the fabric displays pronounced tunability, turning into greater than 35 instances stiffer and altering its damping functionality by 50%.
The metamaterial might be designed to self-actuate, via synthetic tendons that set off the form with out human management
“Our metamaterial enables new capabilities, showing great potential for its incorporation into robotics, reconfigurable structures and space engineering,” mentioned corresponding creator and UCLA Samueli College of Engineering postdoctoral scholar Wenzhong Yan. “Built with this material, a self-deployable soft robot, for example, could calibrate its limbs’ stiffness to accommodate different terrains for optimal movement while retaining its body structure. The sturdy metamaterial could also help a robot lift, push or pull objects.”
Push puppet toys can collapse after which stiffen once more. UCLA developed a tunable metamaterial mimicking the internal workings of push puppets to regulate the form and rigidity of a construction.
“The general concept of contracting-cord metamaterials opens up intriguing possibilities on how to build mechanical intelligence into robots and other devices,” Yan mentioned.
Senior authors on the paper are Ankur Mehta, a UCLA Samueli affiliate professor {of electrical} and pc engineering and director of the Laboratory for Embedded Machines and Ubiquitous Robots of which Yan is a member, and Jonathan Hopkins, a professor of mechanical and aerospace engineering who leads UCLA’s Versatile Analysis Group.
In accordance with the researchers, potential purposes of the fabric additionally embody self-assembling shelters with shells that encapsulate a collapsible scaffolding. It might additionally function a compact shock absorber with programmable dampening capabilities for autos transferring via tough environments.
“Looking ahead, there’s a vast space to explore in tailoring and customizing capabilities by altering the size and shape of the beads, as well as how they are connected,” mentioned Mehta, who additionally has a college appointment in mechanical and aerospace engineering.
Whereas earlier analysis has explored contracting cords, this paper has delved into the mechanical properties of such a system, together with the perfect shapes for bead alignment, self-assembly and the power to be tuned to carry their total framework.
