It can fly over 30 meters in the air: scientists have developed a robot that can jump up to 100 times its size. It exceeds previous artificial jumpers, as well as the efficiency of biological systems. The concept is based on the sudden release of a taut system of springs and rubber bands. For jumps, the technique outperforms biology because of its more efficient options for storing elastic energy, the researchers explain. According to them, jumping robots could economically provide a bird’s eye view of the terrain. This can be especially effective when exploring the lunar surface.
As is well known, there is an alternative way to fly, at least for a short time: people sometimes use jumps to overcome obstacles or to reach something high. Our capabilities, however, are quite modest: the world record is 2.45 meters at a height of 1.93 meters. However, in relation to body size, some animals achieve much higher performance. However, a particularly strong jumping force of insect species such as grasshoppers and the like is based on a concept that is very different from our process.
While humans and other larger creatures use spontaneous muscle contractions to jump, the insect world record holders first accumulate stored elastic energy through muscle tension. Due to certain mechanisms, the potential can be suddenly released, which means that the animals are transported upwards very efficiently. This basic principle of biology has already been used to make robots jump. As reported by scientists led by Elliot Hawkes from the University of California in Santa Barbara, they were now able to take this process to an extreme.
Cleverly promoted to the top
Her jumping robot, 30 cm high, has an aerodynamically shaped head that houses the battery and motor. During the pull-in phase, it produces a rotating motion that winds the line onto the axle. Its lower end is attached to four arched members made of flexible carbon fiber material. When the rope is wound on, they deform under the pulling force and thus store spring energy. This effect is additionally strengthened by rubber bands that are stretched between the elements of the arch like spokes. A full charge is achieved when the wedge attached to the cord contacts the latch in the robot head and snaps into place. This item is then opened to trigger a jump. The tension in the rope breaks immediately and the elastic energy stored in the bow elements and elastics is suddenly released.
According to the researchers, the results of their tests during the tests revealed: The robot, which is 30 centimeters high and weighs 30 grams, is approaching a height of about 33 meters. During take-off, it reaches a speed of over 28 meters per second. According to the researchers, this is the highest performance ever achieved in technical jumpers and also outperforms biological systems. Although some insects achieve a similar body length to jump height ratio, this is limited to light ones, with a take-off speed of only around four meters per second. Weighing 30 grams, Hawkes and his colleagues’ robot is more than ten times heavier than the largest jumping creatures with stored elastic energy concepts.
alternative to flying
The scientists explain that more effective methods of elastic energy storage allow the use of biological methods in the technique. Because the animals’ maximum jumping performance is limited by the effect that their muscles can create in one stroke. On the other hand, the technical bridge potential can reach a higher level as the rotary motor can provide much more stored energy through the winding effect. “Our work helps to better understand the mechanisms involved in jumps, highlights potential efficiencies, and highlights the importance of taking into account the differences between artificial and biological systems,” write Hawkes and his colleagues.
As they conclude, the strength of their design also shows the potential of using jumping robots. They could therefore be a practical alternative to flying objects as they are able to overcome obstacles and reach heights that were previously reserved for drones and the like. This allows them to collect visual terrain data from a bird’s eye view while jumping. This would be of particular interest when exploring the moon, for example: due to the lower gravity, the current model could jump 125 meters and travel half a kilometer in one hop, the scientists write.
Source: Nature, doi: 10.1038 / s41586-022-04606-3