Caribou heavy-lift hexacopter
Open-source heavy-lift hexacopter for Arrow Air: six Hobbywing X15 drives with 63-inch folding propellers, a carbon sandwich frame, and our battery-connector and main boards. 220 kg maximum take-off mass.
Projects
A selection of what we have designed and built. The open projects come with their full CAD, parts lists and build guides.
Longshot battery pack
A 14S9P drone battery of 126 cells of 21700 in printed holders with spot-welded busbars, the Tattu 4.0 connector and latch, and its own power board. Built and flown in 2026.
PT3 battery system
Six independent 24S5P packs of Molicel P45B cells, 11.7 kWh in total, for Arrow Air's PT3 heavy-lift drone. Each pack has its own BMS, contactor, precharge and CAN interface.
Heavy-lift drone frame
An earlier heavy-lift drone frame made of steel and aluminium tubes.
Thrust stand
Test stand for electric motor and propeller combinations.
21700 battery prototype
Built to test the manufacturing process with 21700 cylindrical Li-ion cells.
Signal distribution board
Connects the flight controller to the batteries, ESCs and other devices and routes their signals.
Second-life energy storage
Stationary storage built from used EV battery modules, giving them a second life.
1953 Buick Roadmaster, electric
The first big project, in 2016: a conversion to electric drive with 80 kW and 250 km of range.