Lesson's learned from V1 and initial design

A project log for Bi-Copter V2

The objective of this project is to design a frame for an RC Bi-Copter in CAD with laser cutting in mind

SpencerSpencer 05/18/2016 at 05:020 Comments

Bi-copter V1 was okay... But had severe issues. This is V1 is all his glory.

Some of the problems were easy to fix. For example the wire landing gear produced far to much vibrations so they were replaced by foam blocks. However some problems are not so easy to fix. believeit or not it kept snapping metal gear servo shafts in mid flight.

Now this was likely related to the weird angle the motors are at in this picture. I read online that having them tile at 45 degrees relative to each other can help with stability. This made the design of the mounts quite a bit harder. Due to this the center of gravity of the motors do not line up with the pivot point. In fact the COG is about 10mm higher than the pivot point. This means the servos have to work much harder and potentially explain the snapped gears. However the mounts also had a limit freedom of movement. If the tilted to far either way they would crash against the mount. This could also have been the reason for the breakage or it could even be due to both. So the new design will not feature angled motor mounts.

The new design will also be laser cut. This is due to two reasons. First is that the laser cuter is far easier to use. Second is that due to internal political BS at my college the CNC mill is effectively out of service. However the laser cuter is available instead so it's not all bad.

For V1 I had the pleasure of using Creo parametric. Lets just say I'm not a fan and I don't miss it. For V2 I'm using a student

version of Fusion 360 and it's been working very well. A side affect if that I can enter it in design for auto desk and win a cash prize. Sweet.

Here is my current progress on V2, most of the hard work is already done.