Insect-inspired drone goes soft to avoid crash damage
Drones are pretty adept at a number of things, including the ability to crash into stuff. Obstacle avoidance systems and protective frames are a couple of ways of protecting these fragile flying machines, but one team of researchers is pursuing a different path with a deformable drone that collapses to prevent damage in the event of a crash.
Origami and the animal kingdom are two regular sources of inspiration for the scientists at EPFL's Laboratory of Intelligent Systems. Robotic fish and eels, feathered drones and triangular origami bots are just a few of the creations cooked up by the team in the last couple of years. The researchers have again taken from the lessons of nature and folding paper to develop their latest promising robot.
The hybrid origami drone is inspired by insect wings, which are rigid in load-bearing sections but flexible at the joints. It consists of arms made from stretched membranes that mimic the soft elasticity of the joints, sandwiched between a pair of stiff plates. They are engineered so that when operational, the plates hold the arms out in a rigid state, but when a specific amount of force is applied, the plates break apart and the arms are able to bend.
This design actually builds on an early iteration shared by the researchers last year, which used a thin fiberglass frame, elastic bands and magnets at the joints to form rubbery drone arms that could completely detach from a central module and bounce around to protect it in the event of a crash.
The arms on the new version remain connected to the central module, but have just the right amount of give to still protect components like batteries and electronics that are essential to flight. It can then unfold and be readied for take off at the user's command.
"When we make a drone, we can give it specific mechanical properties," says Stefano Mintchev, the study's lead author. "This includes, for example, defining the moment at which the structure switches from stiff to flexible."
The team says this new design overcomes some of the problems of its previous origami-inspired machines, which generally fall into one of two categories: stiff structures that can bear considerable weight but then break apart under too much stress, and flexible structures that can't carry much weight at all.
"The current trend in robotics is to create 'softer' robots that can adapt to a given function and operate safely alongside humans," says Dario Floreano, who heads up the Laboratory of Intelligent Systems. "But some applications also require a certain level of rigidity. With our system, we have shown that you can strike the right balance between the two."
You can hear from the researchers in the video below, while their work was published in the journal Science Robotics.