Skywalker X8 VTOL Design

Hello all,

I recently received a question regarding my design for my Skywalker VTOL design, so I made this post to outline my design and some tips that I have for those interested in implementing it. The original design idea came from Sander Smeets: http://px4.io/portfolio/quadranger-vtol/

Here are a few pictures of the bottoms of my wings:


New photo by Evan Palmer

New photo by Evan Palmer

The design specifications are here:
Booms:

Plate:

Motor Mounts:

Motors:

Propellers:

ESCs:

Design:

  • Cut the Aluminum tubes into halves and use each piece to glue the carbon fiber tubes together.
  • Attach the plate to the wing
    • The front edge of the plate is 7.25 inches from the front of the wing
    • With the X8 wing, I personally used a dremel and leveled out the wing so that it would sit flush with the wing. Rather than having edges lifted.
    • Tip: Take the small wing joiner pieces off of the wing joiner prior to gluing to avoid gluing the small piece and the wing joiner together. (Yes I have done this before, and no, it is not fun to take them off.)
  • Attach the booms to the wing plate
    • The center of the boom is located 0.75" above the front of the plate.
    • Tip: This is something that I did to ensure that I glued the booms onto the plate square. Take an old shoe box and cut the lid off of the box. Once you have them in two pieces, use the box portion and tape this onto the plate with the edge lined up square and at the distance which you will glue on the boom. When this is taped set the boom onto the plate flush with the box. Then, with the top of the box which you just cut off, line this up against the edge of the boom to guarantee that you have the correct width. This makes it much easier to glue on than drawing lines into the plate and then worrying about gluing the boom onto that exact spot. This way, you can simply put the glue into the gap made by the two parts of the shoe box, and attach the boom.
  • Once the boom has dried, attach the motors
    • With the motor mounts and motors specified above, it will be necessary for you to drill new holes into the mount as the pre-drilled holes will not fit with the mount with comes with the motors.

Side Notes:

  • The Battery Setup which I use is two 4S 5000 mAh batteries with 35C discharge attached in parallel ONLY for the vertical take off and landing. I have a separate battery for forward flight. I will be testing smaller batteries in the future as recommended by the mad genius Darrell Burkey.
  • I personally extended the motor wires on the ESCs rather than the power wires. I have heard people say positives and negatives of both methods, such as that extending the motor wires can result in differences in timing and distortion of signal, and in regards to extending the power wires, there can be a voltage drop over the distance. I have not had any issues extending the motor wires.
  • DO NOT cut holes into the booms to run your wires through. While it may be more aesthetic, those will be the first places to break on impact. Simply tie the wires on with zip ties.
  • At the time of writing this, I forgot to measure the distance between the wing joiner and the inside edge of the boom, I will update that soon.
  • If you have any questions, feel free to let me know!

Thanks for writing this up. I’ve had quite a few questions regarding VTOL conversions and this is very helpful.

Hi
Very interesting. Thank you for sharing!
Can you share your Pixhawk 2 set up please or direct me to where I might find it?
Thanks
Ned

Can you explain a little bit more on the different power system for vtol and foward flight. How do you setup this?

The two different power systems were used to both create a failsafe and to provide extra flight time. Regarding vertical flight, this was done by creating a connector (make sure to use XT90 and not XT60 connectors as XT60 cannot handle this much current) that brings the two batteries together in parallel. From here, the connection is split into four outputs for each of the ESCs. In between the parrallel and branching connection is a power module as well for failsafe and battery monitoring in-flight. Regarding the forward flight power, the typical one battery setup is used.

Hi, can you post your pictures again?
is this build a better suggestion than the one made by the mad genius Darrell Burkey:smile:
i mean this post: Skywalker X8 Quadplane Build 4
i’d like to make the best out of both of them.

I will have to see if I can find them again, but if I do, I will certainly post them. Regarding the better design, I believe Darrell’s is better. This design is easier to build, but Darrell’s is more structurally sound.

The electrical design and layouts are similar. I believe he is trying out some new digital ESCs though.