At the European Robotics Forum in Stavanger, Swedish drone maker Bitcraze demonstrated a swarm of fully autonomous miniature drones capable of avoiding mid-air collisions entirely on their own.
Speaking to Rocking Robots at ERF 2026, Fredrik Ehrenstråle from Bitcraze AB stood in front of a live flying demonstration that drew consistent attention from passersby. Behind him, a cluster of small drones — the company’s Crazyflie platform — circled autonomously inside a mesh cage, their LED indicators shifting colors as they moved.
All the Intelligence Is on the Drone
What makes the demonstration stand out is where the computing happens. “Everything that’s being done by the drones is being done on device,” Ehrenstråle explained. There is no external computer making flight decisions or coordinating traffic — each drone handles its own navigation independently.
The collision avoidance is built on continuous peer-to-peer communication between the drones. Each unit broadcasts its position so that every other drone in the swarm knows where its neighbors are at all times. That shared spatial awareness is what prevents mid-air collisions as the drones circle the enclosure, and it is what allows them to eventually find their way back to their individual charging pads without human intervention.
The color-changing LEDs are more than a visual flourish — they reflect the drone’s internal state and position within the cage, offering a real-time window into the software’s decision-making.
A Platform Built for Researchers
Bitcraze’s primary market is universities and research institutions, though Ehrenstråle noted growing interest from industry as well. The open-source software stack that runs the Crazyflie is deliberately broad in scope, supporting work in swarm algorithms, autonomous navigation, SLAM (simultaneous localization and mapping), and human-computer interaction.
“We are really surprised at just how many directions the community has taken this,” Ehrenstråle said, suggesting the platform has evolved well beyond what its creators originally envisioned.
Swarming Technology and the Dual-Use Question
ERF 2026 dedicated significant plenary time to the question of dual-use technology — civilian versus military applications of robotics — a topic that is impossible to sidestep in the current geopolitical climate. Ehrenstråle acknowledged that public funding for drone and swarming technology has increased sharply, and that Bitcraze is benefiting from that trend.
He was candid about the tension: “You can put a gun on anything,” he said, “but our primary focus is civilian use, for sure.”
Why It Matters
Collision avoidance in drone swarms is one of the central engineering challenges standing between today’s research prototypes and real-world deployments — whether for warehouse logistics, infrastructure inspection, search and rescue, or any scenario where multiple drones must operate in close proximity without a human managing each one. Bitcraze’s on-device, peer-to-peer approach is a practical demonstration that the problem is solvable at small scale today, with the research community pushing the boundaries further.
