Engineering Commons^™

Membrane-Enhanced Lamina Emergent Torsional Joints For Surrogate Folds, Guimin Chen, Spencer P. Magleby, Larry L. Howell

Faculty Publications

Lamina emergent compliant mechanisms (including origami-adapted compliant mechanisms) are mechanical devices that can be fabricated from a planar material (a lamina) and have motion that emerges out of the fabrication plane. Lamina emergent compliant mechanisms often exhibit undesirable parasitic motions due to the planar fabrication constraint. This work introduces a type of lamina emergent torsion (LET) joint that reduces parasitic motions of lamina emergent mechanisms (LEMs), and presents equations for modeling parasitic motion of LET joints. The membrane joint also makes possible one-way joints that can ensure origami-based mechanisms emerge from their flat state (a change point) into the desired …

Regional Stiffness Reduction Using Lamina Emergent Torsional Joints For Flexible Printed Circuit Board Design, Bryce P. Defigueiredo, Brian Dale Russell, Trent K. Zimmerman, Larry L. Howell

Faculty Publications

Flexible printed circuit boards (PCBs) make it possi- ble for engineers to design devices that use space efficiently

and can undergo changes in shape and configuration. How- ever, they also suffer from trade-offs due to non-ideal mate- rial properties. Here, a method is presented that allows en- gineers to introduce regions of flexibility in otherwise rigid

PCB substrates. This method employs geometric features to reduce local stiffness in the PCB, rather than reducing

the global stiffness by material selection. Analytical and fi- nite element models are presented to calculate the maximum

stresses caused by deflection. An example device is produced …