nnChipmunk - 800mm
Part 6 - How to Design DTFB Planes
So right after finishing version 1 of my laser cut foldable quad I decided to go for a second version of the frame to introduce some improvements that were needed from my previous build.
The landing gear was quite unstable, I've gone through a couple of iterations of the design. The first version the legs were too short and didn't fit very tightly into the booms.
I attempted to build a second version which had two parts to fit as a + into the boom anchored using zipties. I found this design complicated and it's quite difficult to get the tolerances right for a flush fit.
The final version was based on boat masts, think of a forestay and backstay holding the arm into the boom, by moving the ziptie anchors down the landing gear I think I have created a nice compromise solution that doesn't remove too much material on the boom. Keeping with that design decision, all ziptie anchors on the booms and landing gear have a significantly reduced area, again to remove the least amount of material.
My original design used two layer plates but atter building it, I found that having two was an overdesign. I decided to merge all of the features of both plates into one (for more details on the layer plates you can check the "layerd approach" heading in my previous article). I've also done some minor tweaks like adding orthogonal velcro strap anchors. Additionally, one set of ziptie anchors can be used to mount the KK2 boards (original was designed only to accept the v1 board) using M3 nylon screws or zipties. Another key innovation, is the little gap at the edge of the plate to allow the builder to pop-in cables in the cable feed hole. This improvement makes mounting ESCs onto the plate a lot easier.
I've gone through a few motor mount designs to get to v2. I wanted to maintain the ability for the builder to use zipties to mount the motors while also allowing the builder to use M3 screws to mount their motors. I've tried to keep a balance in the design by not removing too much material while being functional, I think I hit the sweet spot.
Please share your comments below and checkout my build in the forum. Also please don't forget to rate this article!