Bistable Insect-Scale Jumpers with Tunable Energy Barriers for Multimodal Locomotion.

Drawing inspiration from the jumping mechanisms of insects (e.g., click beetles), bistable structures can convert slow deformations of soft actuating material into fast jumping motions (i.e., power amplification). However, bistable jumpers often encounter large energy barriers for energy release/re-storage, posing a challenge in achieving multimodal (i.e., height/distance) and continuous jumps at the insect scale (body length under 20 mm). Here, a new offset-buckling bistable design is introduced that features antisymmetric equilibrium states and tunable energy barriers. Leveraging this design, a Boundary Actuation Tunable Energy-barrier (BATE) jumper (body length down to 15 mm) is developed, and transform BATE jumper from height-jump mode (up to 12.7 body lengths) to distance-jump mode (up to 20 body lengths). BATE jumpers can perform agile continuous jumping (within 300 ms for energy release/re-storage times) and real-time status detection is further demonstrated. This insect-level performance of the proposed BATE jumper showcases its potential toward future applications in exploration, search, and rescue.