Hello everyone! I have 3D printed, built, and flown a T4 Quadcopter Drone
I’m going to use this space to log the testing process.
Goal: To build a 3D printed robotics platform. End goal will be ROS2 on a companionon computer and either 360 lidar or a few 3d depth cameras.
3D printer- Creality CR30 Belt printer
Filament- 3DPrintLab Polyair Red
Temp: I need to doublecheck this, I printed the parts a long long time ago.
Printer running Klipper Firmware, otherwise stock.
Holybro Pixhawk 5X
Holybro H-RTK M8P GNSS Rover lite
Holybro H-RTK M8P Base Station
SpeedyBee F405 BLS 50A 30x30 4-in-1 ESC
Holybro PM02D Power Module
SIYI HM30 Telemetry/Radio Control/1080P Radio
FRSKY X8R Reciever
RadioMaster Zorro TX
4S 3000mah Battery
1045 slowfly props
850KV D2830 Brushless motor
3.5mm Bullet Connectors
28Gauge wire (ESC)
30 Gauge wire (Radio connections, ESC DSHOT)
First Flight here: 3D Printed Quadcopter Drone. First flight. Pixhawk 5X. 10" props. - YouTube Manual into Altitude into Position. Defaults for generic quad for PID settings.
My 2nd flight ended in failure. I forgot to threadlock my motor mounts. I meant to do a very very short flight to ensure the motor wiring was OK, then threadlock everything into place + ziptie the end of the motor wires down. Got excited to fly and completely forgot. I damaged 1 arm that needs to be replaced and everything else is A-OK. It fell from about 6 feet straight to the concrete, so good all things considered. I think that arm had a bit of under extrusion anyways…so we will see in other crashes how the other arms fair.
Completed flight 3, 4, and 5. I’m also going to upload logs for all flights starting today along with any videos and pics I take.
Flight 4 and 5 stats:
Battery- 3300mah 4S
Air Temp- 80F
New Polycarbonate Carbon Fiber Arms.
Video:flight 4- 3d printed quadcopter T4 - YouTube
Autotune performed then landed after a quick test flight.
Video:Flight 5- 3d printed 10" quadcopter T4 - YouTube
Test flight in altitude + position test. Very sloppy on position. Slow and uncoordinated.
After our crash on Flight 2- I had to evaluate what went wrong and how to prevent it in the future. At first I thought it was the lack of threadlock on the motors that allowed it to quickly come free. After flight 3 I learned that the motors were becoming incredibly hot, which was softening the polyair plastic significantly. This allowed the the motors to move freely in their nacelles as that is how soft the plastic was. The bolts on the bottom of the motors were very hot to the touch. I’m certain this is what caused the 1st crash. They softened significantly and then started coming loose.
During Assembly I also noticed that the motor recommended on the T4 thingiverse page had vent holes that didn’t quite line up with the vent holes built into the 3d printed arm. This contributed to how hot the motor got in that nacelle.
What we changed for flight 4 and 5.
I asked my good friend and neighbor, Matt, if he would reprint the arms for me in polycarbonate carbon fiber. Instead of using the stock arms, I switched to a new design that claimed to fix the vent hole problem and changed the top of the design a bit to allow more air around the motor. The new arm can be found here: Improved ventilation T4 arm by oseiler - Thingiverse They turned out beautifully and I made quick work to get them on the quad. We also changed the stock screws they included for bolts with a washer. We then threadlocked them in.
Up next- Continue PID Tuning and Position tuning. Then add optical flow/lidar - ArkFlow