Helicopter: Align TREX 450 Pro V2 build plan!

This is a to-do list and build plan for the Trex 450 V2 flybarless helicopter, APM/FPV/sUAS build, so expect a lot more posts based on what you see below. I highly suggest you make your own plans like this, as it takes a lot off of your mind when its all layed out in digital bits.

DONE: visually check all parts prior to assembly, and circuit boards with loupe for poor solder joints
DONE: assemble frame, bolts finger tight
DONE: mod: dual thrust torque boom bearings to reduce tail boom vibration. Add tail motor if necessary. Pic below.
DONE: mount Gopro, used Moolgel and Tarot “card” system…though modified. Pic below.
DONE: make skids, for frame level and camera mount. *no pic yet*
DONE: kapton tape all circuit boards, for water and dust. Then wrap in aluminum foil tied to ground, then wrap in kapton again

-solder new  wiring plug on 1258Mhz video transmitter, I hate DF13 connectors! They are too fragile. Replacing with two JST connectors
-mount 1258Mhz video transmitter
-mount magnetometer, upgrade HMC-5983
-wire and mount power supply (BEC) for discreet power for APM and 433Mhz rx to prevent brownouts due to servo electrical draw
-balance props, remove weight if all possible. Tape is last resort.
-mount servos
-mount FPV camera
-remove and Blue-loctite all bolts, careful to keep off loctite off plastics
-mount 433Mhz receiver
-make 433Mhz dipole antenna, or turnstyle type
-mount 900Mhz telemetry
-make 900Mhz antenna
-mount “minimosd extra” HUD video overlay (already programmed, procedure here)
-program ESC, set RPM governor. 2500rpm???
-add foam over barometer, to smooth the pressure differential. Makes APM more stable in auto and loiter.
-foam up Microphone for wind, place inside frame
-set up RC transmitter for *airplane*, APM likes non-mixed inputs
-program APM (arduino/gyro/flight controller/arducopter)
-set servos 90 degrees and tie in linkages
-double check all electrical
-full power up, test all electrical
-evaluate RF noise for RF interference abatement, LCfilter/torroid placement, planning on using none due to shielding, component spacing and twisted pair cat5 wiring throughout. Don’t want the extra weight. Use a RTL-SDR for evaluation.
-lightly lube all gears
-double check all mechanical parts
-spin up motor while copter is anchored, evaluate APM vibration log
-test RC inputs work with mechanics
-log all up weight (auw)
-check final center of gravity (CG)
-take pictures, this is the best it will ever look
-check ground station FPV gear and Mission Planner
-maiden 1, spin up, frame tied to ground. Test control surfaces
-maiden 2, take off 5′ then land
-maiden 3, repeat 2
-maiden 4, fly a *short* distance, return and land
-maiden 5, repeat 4
-maiden 6, test APM auto modes
-maiden 7, repeat 6
-flight check then normal flight


Radio Frequency (RF) Real Estate Map.

-frequency spacing- nose to tail:
433Mhz KnownGopro-Interference, 900MhzTelemetry, 1258MhzVideoTx, 1227/1575MhzGPS, 433MhzRxDipoleMountedOnTail………..the idea is to keep the noise up front and quiet at the tail. RF energy is logarithmic, so the more distance you place between the items of interest the less they will interfere. ….(433Mhz Interference from Gopro in the front, Tx in the center, critical receivers on the tail)

-potential interference directions and radiated/received RF:
433MhzGopro.interf/tx.Omni, BroadbandMotor.intref/tx.Omni, 900Mhz-TelemRxTx-omni/down, 1258-Vtx-omni/down, 1227.60/1575.42GPS-Rx-omni/up, 433-Rx-omni/down. [Vtx and GPS are close, however the Vtx is narrow band and doesn’t interfere.]

P1010084 (Large)

P1010078 (Large)

P1010085 (Large)


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