Solar-powered shape-changing origami microfliers

Abstract

Using wind to disperse microfliers that fall like seeds and leaves can help automate large-scale sensor deployments. Here, we present battery-free microfliers that can change shape in mid-air to vary their dispersal distance. We designed origami microfliers using bistable leaf-out structures and uncovered an important property: A simple change in the shape of these origami structures causes two dramatically different falling behaviors. When unfolded and flat, the microfliers exhibit a tumbling behavior that increases lateral displacement in the wind. When folded inward, their orientation is stabilized, resulting in a downward descent that is less influenced by wind. To electronically transition between these two shapes, we designed a low-power electromagnetic actuator that produces peak forces of up to 200 millinewtons within 25 milliseconds while powered by solar cells. We fabricated a circuit directly on the folded origami structure that includes a programmable microcontroller, a Bluetooth radio, a solar power–harvesting circuit, a pressure sensor to estimate altitude, and a temperature sensor. Outdoor evaluations show that our 414-milligram origami microfliers were able to electronically change their shape mid-air, travel up to 98 meters in a light breeze, and wirelessly transmit data via Bluetooth up to 60 meters away, using only power collected from the sun.

Integrated Actuation and Sensing: Toward Intelligent Soft Robots

“…Includes solar cell-powered electromagnetic actuator with pressure and temperature sensors for altitude estimation. Reproduced with permission from [ 145 ].…”

“…7 E. In addition, Johnson et al. [ 145 ] designed a low-power electromagnetic actuator powered by a solar cell that allows a robot to generate a maximum actuation force of up to 200 mN in 25 ms. The researchers also fabricated a circuit on a folded origami structure that included a programmable microcontroller, a Bluetooth radio, solar energy harvesting circuitry, pressure sensors for estimating height, and temperature sensors (Fig.…”

Reconfigurable origami-inspired multistable metamorphous structures

“…Origami morphing structures have been extensively developed in fields such as robotics (14)(15)(16)(17)(18)(19)(20)(21), mechanical metamaterials (12,(22)(23)(24)(25)(26) and aerospace deployable structures (27)(28)(29). To achieve morphing, some origami structures rely on the switch of mountain and valley assignments of creases to alter folding motions (30)(31)(32)(33)(34), whereas others use flexibility of the materials to obtain multistable metamorphous structures (5,13,19,24,25,(35)(36)(37). At present, most such structures adopt a particular shape-changing mechanism or design from which almost all functions are derived.…”

Functional bio-inspired hybrid fliers with separated ring and leading edge vortices

“…Recent efforts focus on the development of passive flier systems inspired by wind-dispersed seeds for potential applications in environmental monitoring and other contexts that require coverage of electronic components or functional materials across vast spatial scales ( 13 ). Examples range from battery-free wireless ( 14 ), light-driven ( 15 , 16 ), biodegradable ( 17 , 18 ), shape-morphing ( 19 , 20 ), and power efficient ( 21 ) flier systems inspired by various wind-dispersed seeds including parachuting, autorotating, and gliding types. Contemporary advancements in soft electronic technologies create the possibility for integrating miniaturized electronic payloads conformal to nearly any 3D deformable surface ( 22 ), including curved wing areas with different shapes ( 13 , 18 ).…”