Origami-inspired, versatile fabrication of millimeter-scale mechanical devices

The fabrication of mechanical devices on the millimeter scale is a critical capability for autonomous microrobots and micromanipulation devices, and is important to manufacture active components in optical switches and smart antennas. However, available manufacturing technologies lack the versatility, precision, and cost-efficiency to produce large quantities of functional devices at this scale.

The present invention is a revolutionary manufacturing process inspired by origami, which enables the manufacture of complex electromechanical systems, such as medical devices, small robots, or specialized sensors. Furthermore, the process allows for the use of a wide variety of materials, including alloyed metals, polymers, and carbon fiber sheets, to create complicated kinematic linkages, support structures, and assembly-assist features on a single layup. Full subcomponents such as motors, ICs, and batteries can also be integrated into devices during this fabrication process. The invented process employs low-cost, low-power operations such as laser micromachining, press lamination, and folding techniques to greatly reduce assembly expense and increase process scalability.

For example, we present the “Monolithic Bee” robot. Fabrication starts with the laser micromachining of several material layers, ranging from structural carbon fiber sheet layers to flexible polyimide layers joint to create foldable joints. Laser micromachining creates patterns necessary for mechanical coupling, the release of rigid bodies comprising mechanical linkages, and the removal sacrificial material. Two piezoelectric transducer (PZT) plates used for device actuation are seen at the bottom of the image.

Fifteen micromachined material layers used in the Monolithic Bee robot

After the initial micromachining, the material layers are aligned for press lamination using dowel pins and assembly-assist features cut into the layers. Micromachining and lamination operations can be performed several times on layups containing subsets of the device’s layers. After the insertion of the discrete PZT subcomponents into the layups, the set can be laminated together to form a complete device, and functional components can be released with additional laser micromachining.

Monolithic Bee material layers stacked in a layup for press curing

After removal of the fully machined and laminated layup, the “Monolithic Bee” device is removed in its superplanar form. At this point, the 2D planar device is assembled by “pop-up” using a few assembly degrees of freedom built into the device’s structure. The final 3D “pop-up” form of the Monolithic Bee” device can then has its assembly degrees of freedom frozen in place using dip or wave soldering, completing the fabrication process.

Monolithic Bee robot after release from scrap materials, and after “pop-up” assembly

U.S. Patent(s) Issued: WO/2012/109559