...
A straightforward reaction wheel design would have maximum OD of 5.5 in or .14m. The 335kv motors can obtain a max RPM of 4800. Conservatively using 3500 RPM or 583.3 hz, we can calculate the necessary moment of inertia of the reaction wheel to be
which is a disk of 0.8kg or a thin walled tube of 0.4kg.
| Mathinline | ||
|---|---|---|
|
These design parameters were translated into CAD. A steel tube is used to provide most of the wheel inertia, with an aluminum support and a bearing set providing constraints. A PTFE wear ring keeps the disk from riding. A thin shim stock raceway protects wires running from avionics to the payload. All components except the bearing seat mechanically mount to a new aluminum bulkhead. The system has an optimized mass of 840g. Superior performance is almost certainly possible, given the wheel mass of 390g and the motor ass of 205, which comprise the only 'essential' components of the system.
Hardware
Pyxida will send I2C commands to a Teensy 3.5 which will PWM Control 60A Hobbyking ESC units that drive Quantum MT motors. The system is powered by a 4s LiPo battery.
...