Folding TriCopter for 15.5mm with OpenSCAD Source - Remixed

thingiverse

This CoaxQuad is a reinterpretation, based and inspired on the David Windestål design work at RCExplorer.se. If you haven't seen David's fantastic new v3.0 design, I recommend visiting his site and supporting him. This design enables the use of 15.5mm Towel Rack available at Home Depot which is significantly stronger than the 10mm x 10mm wood booms, while being very easy to obtain in the States, since Home Depot and Lowes are nearly everywhere. Plus you can edit the SCAD source to make the parts fit any size boom you wish. I modified this design and moved things into OpenSCAD to allow for using the CoaxQuad as a project for a MultiRotor building workshop. The source allows you to make each part or modify it to meet your needs. It supports wiring through the booms, as well as Naze32 (30.5mm x 30.5mm) flight controllers as well as APM mounts. Optionally you can use LiPo strapped directly to the center of the frame instead of the combination battery & camera tray. Motor Mounts remixed from shmorgan: http://www.thingiverse.com/thing:108762. Body Base remixed from peddiparth: http://www.thingiverse.com/thing:231205. BatteryTray remixed from bobunobo: http://www.thingiverse.com/thing:402931. I am currently building the prototype, and hopefully have a maiden shortly. I used 28xx 1200kv Motors with Afro 30A SimonK ESCs for testing of different props, however 2212 900kv Motors with 20 AMP ESCs should be fine and reduce weight. Also note I used a stand alone Castle Creations 10 amp Switching BEC, since I am using a digital servo. Analog servo would be fine, and would draw a lot less current. For Yaw Tail Rotor servo: I used a Savöx Micro digital servo Savöx SH-0257MG, most Micro style with Metal Gears should be fine. Analog: Hitec HS-82MG or HS-85MG. Digital: Savöx SH-0257MG or Hitec HS-5085MG. Servo mount area space is 30mm x 13mm x 30mm. Yaw Motor Mount, acts like a rear leg, and the top tilt motor mount is retained by a M4x40mm, and you have the option of using either side or front ball links. Side give you more throw, while front is neater in appearance. You can mount and use a Mobius and a GoPro at the same time. Mobius on the upper deck, and the GoPro on the bottom tray. For FPV, I'll use my http://www.thingiverse.com/thing:230797 mounted on one boom and the cam mounted on front upper deck. Folded Size: 670mm x 100m. Unfolded: 770mm x 905mm. Measured propeller tip to propeller tip. Maiden: 22-Nov-2014: Flight time 8m 23s. Props: APC 8 x 4.5 MR. LiPo: ReadyMade RC 3s 2200 @ 176g. AUW: 1052g. Print at .2mm layer height, 4 shells, 20% infill. Recommend that all wire for tray be printed on the plate. This allows for better fitment. Invert Wire Bend template needs to be rotated 180 degrees to print without support. Use 1.5mm x 1m Music Wire for Camera/Battery Tray vibration damping: K & S Metals Part# 3942 1m rod $3.75. Grainger Item #3L592 108 foot roll $4.53. To use the Simple Legs with LEDS, use a translucent PLA or ABS, then when the LED is lit, the entire leg will glow, it's a cool effect. Additional instructions to be developed. All parts can be printed without support, however you will need to rotate a few of them: MicroServo Control Horn, TC Wire Bend Template, and TC Yaw mount to print laying on its side. Naze32 Settings currently with base flight. TriCopter. Reverse Accel/Gyro Servo. Set MOTOR_STOP. PPM (for use with Immersion RC 4 Channel Lite, mounted under the Naze32) planning on moving to cleanflight firmware shortly. Taranas 9XD Settings. Adjustable Expo @ 0, 35%, 65%. I could shorten many of the cables, possibly saving another ~40g.