A swarm of 10 bright blue drones takes off in a bamboo forest in China, then weaves its way through cluttered branches, bushes and over uneven ground as it autonomously navigates the best flight path through the forest.
The experiment, led by scientists at Zhejiang University, evokes scenes from science fiction — and the authors, in fact, cite movies such as Star Wars† Prometheus, and Blade Runner 2049 in the opening of their article published in the magazine on Wednesday Science Robotics†
“Here we are taking a step forward (towards) such a future,” wrote the team led by Xin Zhou.
In theory, there are numerous real-world applications, including aerial maps for conservation and disaster management. But the technology had to mature so that flying robots can adapt to new environments without crashing into each other or objects, endangering public safety.
Drone swarms have been tested in the past, but either in open environments with no obstacles, or with the location of those obstacles programmed into them, Enrica Soria, a roboticist from the Swiss Federal Institute of Technology Lausanne, who was not involved in the study, told AFP.
“This is the first time a swarm of drones has successfully flew outdoors in an unstructured environment, in the wild,” she said, adding that the experiment was “impressive.”
The palm-sized robots were purpose-built, with depth cameras, elevation sensors and an on-board computer. The biggest advance was a smart algorithm that includes collision avoidance, flight efficiency and intra-swarm coordination.
Since these drones do not rely on external infrastructure, such as GPS, swarms can be used during natural disasters.
For example, they can be sent to earthquake-affected areas to assess damage and determine where aid should be sent, or to buildings where it is unsafe to send people.
It is certainly possible to use separate drones in such scenarios, but a swarm approach would be much more efficient, especially given the limited flight times.
Another possible use is to have the swarm collectively lift and deliver heavy objects.
There’s also a dark side: swarms can be armed by military personnel, just as remote-controlled single drones are today. The Pentagon has repeatedly expressed interest and is conducting its own tests.
“Military research isn’t just shared openly with the rest of the world, so it’s hard to imagine what stage they are at in their development,” Soria says.
But progress shared in scientific journals can certainly be used for military use.
The Chinese team tested their drones in different scenarios: swarming through the bamboo forest, dodging other drones in a crowded experiment, and having the robots follow a person’s lead.
“Our work is inspired by birds that fly smoothly in a free swarm through even very dense forests,” Zhou wrote in a blog post.
The challenge, he said, was balancing competing demands: the need for small, lightweight machines, but with high computational power, and establishing safe trajectories without massively increasing flight time.
For Soria, it’s only a matter of a few years before we see such drones being deployed in the real thing. But first they need to be tested in ultra-dynamic environments like cities, where they constantly encounter people and vehicles.
Regulations will also have to be caught up, which takes extra time.
© Agence France Presse