ERC 2025: Freya's First Visit to Krakow

In late August 2025, our team packed rover Freya, a custom-built F450 drone, and a van filled to the brim with equipment and headed to Krakow, Poland. Our destination: the European Rover Challenge, the largest planetary robotics competition in Europe, hosted at AGH University of Science and Technology.

It was our first time competing. The team was founded less than two years prior at Brno University of Technology, pulling together students from five faculties: FEKT, FSI, FIT, FCH, and FP. We had no legacy hardware, no prior competition experience, and a rover built entirely from scratch.

The Competition

ERC 2025 drew over 100 teams from 33 countries. Only 25 were selected for the on-site finals. We were among them, the only Czech team to qualify. The competition consisted of five tasks: Science (exploration, sampling, astro-bio), Navigation (autonomous traverse + drone mission), Maintenance (panel manipulation), Probing (sample collection), and Presentation.

Standout Performances

2nd Place: Drone Navigation. Our F450 drone, running PX4 on a Pixhawk CubeOrange with a Jetson Orin Nano companion computer, executed autonomous takeoffs, precision landings on ArUco markers, and probe detection across three consecutive missions inside the drone cage. The combination of YOLO-based object detection and reliable flight control put us ahead of teams with years of drone development experience.

2nd Place: Probing. The probing task required Freya to locate, collect, and transport three aluminum probes scattered across the Mars Yard, all under time pressure. Teleoperated by our drivers, the manipulator arm powered by stepper motors handled the probes with surprising precision. Combined with efficient driving, we finished in competitive time.

11th Place Overall. Across all five tasks, we placed 11th out of 25 finalists. For a team competing for the very first time against established programs with multi-year development cycles, this was a strong validation of our engineering approach.

Lessons Learned

ERC 2025 taught us more in four days than months of lab work. The key takeaways:

• Field conditions are brutal. Sand, dust, uneven terrain, and sun glare exposed every weakness in our mechanical design. Our rocker-bogie suspension held up, but we identified critical improvements needed for the chassis legs and wheel-terrain interaction.
• Autonomous navigation is hard. Our VIO system drifted under dynamic conditions, and IMU data from the drone was heavily corrupted by motor vibrations. GPS-denied navigation remains our biggest technical challenge.
• Reliability beats performance. The teams that scored highest weren't necessarily the most advanced; they were the most reliable. Simple, robust systems that work every time outperform complex ones that fail unpredictably.
• Presentation matters. The ERC judges care deeply about engineering process, team organization, and communication. Technical excellence alone isn't enough.

What's Next: ERC 2026

We're already building Freya 2026, and the goal is ambitious: drop from 72 kg down to around 50 kg. The wheels and wheel assemblies are being completely redesigned. The manipulator arm is getting a full overhaul, replacing the stepper motors with Cubemars actuators and CNC-machined joints. The drill mechanism is being rebuilt from scratch. And the autonomy software is receiving a huge update to close the gap on GPS-denied navigation.

ERC 2026 takes place September 4–6 in Krakow. We're coming back, and this time, we know what to expect.

Freya being prepared for competition at AGH University, Krakow

Brno Mars Rover Team