Jumping Robot Reaches Tallest Height of Any Jumper

A mechanical jumper developed by UC Santa Barbara researchers has reached new heights — roughly 100 feet to be exact. The UCSB team, led by engineering professor Elliot Hawkes, was motivated by a desire to understand the limits on engineered jumpers, uniting centuries of study on biological jumpers with the more recent lines of inquiry into bio-inspired mechanical jumpers. Ultimately, by following both lines of inquiry, the team hoped to understand whether engineered jumpers are really limited by the same laws as biological jumpers. The resulting design — which represents a novel approach to jumping devices and an advancement in our understanding of jumping as a form of locomotion — is capable of reaching the tallest height of any jumper to date, engineered or biological.

The research, published in Nature, highlights the limiting factor in biological systems — they can only jump with as much energy as they can produce with a single stroke of their muscle. So what happens when it is possible to increase the amount of energy available? Engineered jumpers use motors that ratchet or rotate through many strokes, multiplying the amount of energy that can be stored in their spring. This ability, termed “work multiplication” by the team at UCSB, is found in engineered jumpers of all shapes and sizes.

These insights led to a jumper quite unlike any animal—the size of its spring relative to its motor is nearly 100 times that of the correlated biological parts. The spring itself is novel, a hybrid tension-compression design in which carbon-fiber compression bows are squashed while rubber bands are stretched, pulled by a line attached to a motor-driven spindle. The hybrid design, strengthened by linking the outward-bound edges of the bows through the center with rubber held in tension, serves to maximize the spring’s energy storage per mass.

The jumper is also lightweight and aerodynamic — the latching mechanism that releases energy for the jump is minimalistic, and the legs fold in to minimize air drag. Altogether, these features allow the device to achieve an acceleration force of 315g — from 0 to 60 mph in 9 meters per second — and jump to a height of approximately 100 feet during demonstrations, shown in a video posted to Nature’s YouTube channel.

These measures of height and force exceed the limits set by biological designs, allowing for a reimagining of jumping as an efficient form of machine locomotion. Jumping robots could reach places that were previously only reachable by flying robots. Away from Earth’s gravity, where the benefits would be more pronounced, jumping robots could traverse planetary terrains quickly and access features and perspectives unreachable by ground-based robots. As Hawkes told the UCSB Current, “That would be one giant leap for engineered jumpers.”