Prizes
Grand prize
$1,500
Highest total across all six stages, bonuses included.
Stage prizes
$250
Highest score in each of the six stages.
Best design history
Sponsor prize
Best documentation
Sponsor prize
Best physical build
Sponsor prize
Community reach
Sponsor prize
$3,000 in cash prizes. The judges decide the four sponsor prizes. Community reach goes to the entry with the highest community interest score, from stars and forks, across the stages. Sponsor prizes are announced here as sponsors confirm.
Key dates
Registration
Open now
Closes 25 Jul 2027
Stage 1 opens
1 Mar 2027
Stage deadlines
Last Sunday of each month
23:59 UTC
Final deadline
29 Aug 2027
23:59 UTC
Stages
One stage per month. Each one builds on the last.
| Stage | Month | Deliverable |
|---|---|---|
| stage-1 Thesis and airframe | Mar | A thesis stating what the drone is for and the requirements that follow. Arms, body, landing gear and motor mounts as STEP. Printable or machinable. |
| stage-2 Electronics layout | Apr | Flight controller, ESC and battery mounts, cable routing. PCB outline if custom. |
| stage-3 Propulsion | May | Motor selection and prop guards. Thrust math documented in the repo. |
| stage-4 Control and sensing | Jun | FC mount, camera or sensor gimbal, antenna placement. |
| stage-5 Integration | Jul | Full assembly, interference check, mass budget, BOM. |
| stage-6 Release and remix | Aug | A v1.0 release with build guide, BOM and drawings. Fork another team's entry, remix one subsystem, and open a pull request. |
How it is judged
- Engineering quality35
- Design process20
- Integration with prior stages20
- Documentation15
- Community interest10
Stages 1 to 5 are scored out of 100 as above. Stage 6 scores your release (50) and your remix of another team's entry (50). Every stage also offers up to 10 bonus points for merged pull requests from outside contributors, and up to 5 for a physical part.
There is no minimum commit count, but judges read your whole history, so a single deadline-day commit scores below a month of small commits.
Rules summary
- One public Nurbly repo per team, with
nbc-2027in its name or description. - All models as STEP, from any CAD tool.
- Tag each stage
stage-Nbefore the deadline. - Start with a thesis: what your drone is for.
- Civilian, lawful designs only.
- Late joiners welcome from any stage.
- Participants keep their IP.
- You must be 18 or older.
FAQ
Do I need to build the drone physically?
No. A physical build is optional. Each stage offers a bonus of up to 5 points for a photo of a physical part of that stage's subsystem, at any scale.
What CAD tool do I need?
Any tool that exports STEP. Nurbly shows STEP files in 3D right in the browser and compares revisions face by face, so judges can see how your design changed. Native files, like SolidWorks parts, can live in the repo too. Only STEP gets the 3D view.
Do I need to know Git?
No. Nurbly runs on Git, but you never type a git command. Upload files in the browser,
or use the free nrb command line tool and desktop companion, which offers to
check in changes from your system tray.
What does Nurbly cost?
Nothing. Challenge repos are public, and public repos on Nurbly are free with no limit on collaborators. A team of any size can compete on free accounts.
How big can our repo be?
A free Nurbly repo holds up to 500 MiB. That is plenty for STEP files. Keep build photos and videos compressed.
Can I join late?
Yes. You can join from any stage until registration closes on 25 Jul 2027. A late team can win the stage prize for any stage it submits, and the grand prize if it submits stages 4, 5 and 6.
Where do I ask questions?
Email us at . You can also ask on our Discord.