More Quadcopter

With FRC finally over, I have been able to actually work on other things as well getting around to updating this, which I admit I do suck at a lot...

The more time I spent flying my Quadcopter the more I realized it was a bit undersized for flying with the GoPro and in general a bit to small (for my tastes).  So with this so called free time I build another one! I decided on using the same KK2 controller with a similar style frame, the KK2 for $25 is an amazing control board and with the new 1.5v firmware works even better. Auto level has been improved quite a bit since the first revision and now almost snaps to level instantly.

Now for the build. A nice photo montage to show some progress, I need to work on taking photos though out the build instead of just the end product...
The main plates are now G10/FR4 instead of delrin, 1/8 thick for the body and 1/16th thick for the landing legs.

However because of the epoxy and fiber bend of G10 I wasn't able to cut it with the laser since it just burned. So had to used the Tormach CNC mill, and using a brand new carbide 1/8th endmill at 5000 RPM I was able to go at it with 1/16th DOC at 40 IPM so it didn't take long. Designed in solidworks and then CAMed with HSMxpress as usual.

Because the G10 stock I got off McMaster-Carr had this horrible white color to it, everything got murdered out. And in all seriousness a good looking paint job, makes a bit difference in what people perceptive. It always happens in FRC where the painted/powercoated/anodized robots are always joked about being "mentor/sponsor built" and usually do perform better because they are better built.

In addition the arms are now thin walled aluminum, .5in square with 40 thou wall thickness, a good improvement over the polycarb box. Because getting this type of aluminum isn't an standard extrusion they are actually sourced from towel racks. And again I used the tormach CNC to drill all the holes for mounting. After I was done with that, I was able to bolt the the frame together! Held together with 4-40 SCHS and lock nuts.

This is probably one of the better/sexier looking things I have built, again the paint and machined tolerances gives it a good look. I do get people asking me if this was a kit, and it does kinda look like the Talon Frame Kit off HobbyKing (totally couldn't have bought that).  Well the rest of the work was just adding the electronics and wiring. I deiced to go with bigger NTN 35 1100kv motors  on 3S and 10x5 blades for what I figured to be the optimal life to power draw ratio. So more photos!

I am using my Spektrum DX6 radio and noticed that you can get $6 6 channel receivers on HobbyKing...... however this unit seemed to bugged out and I am replacing it with a legit Spektrum branded one, about 10x the cash but totally wroth it. Cheap Chinese electronics are cheap for a reason.

And here's the post build product shot! With Gopro which is just hanging with an adhesive mount, shock mount is in the planning. I added an LED light strip to the front which helps with orientation at night but besides there isn't really any aid for orientation.

And here's some goPRO Video!

What goes up, must come down

Now I have been lazy with posting on this and all... this being the blogging and stuff but...

IT FLIES.

Using square lexan from McMaster worked out well, the stuff is more flexible then carbon fiber but much less prone to cracking or splitting and relatively cheap. Getting the KK2 chip tuned in was a bit of a hassle however once I learned to turn on height damping. This effectively keeps the quad from dropping when you do any kind of maneuvers. Now technically you are suppose to do this by yourself, add a bit of throttle when you tilt forwards but used to driving FRC robots at 100% power this was a learning curve... So cheating and making the on board gyros/accelerometers do all the work with some finely tuned PIDs makes flying this thing almost easy.

However I did in the process of tuning and learning to fly go though all my props *sigh...
New ones are on the way as well as more flight training.

Here's a pic just before I broke the last prop:

Failure is always an option.

Well there it was this morning, looking pretty good. There was one more plate to be bolted on over the KK2 for the battery to be velcroed to. Everything seemed pretty solid and all the electronics powered up and tested fine. The KK2 was an pleasure to setup and do the initial ESC and sensor calibrations. So I strapped on a battery and went outside to do some flight testing on it; now my RC flying skills or lack thereof are a bit rusty. And well some of my design choices could have been better so what the quad looked like after the flight...

Yeah... and specifically:

 Bad material choice bites me in the ass

The carbon fiber tubes split nicely along the seams after a few hard landings and eventually came apart. Well lesson learned cheap carbon fiber from China has some issues. Tube was a 10mm square with an 8mm circle running through it so the walls were only 1mm thick on each side; and all the fibers running in one direction... With the rails completely useless I disassembled the quad and cleaned off the dirt from it and planned out revision 2. Now the few tries I was able to get the thing in the air successfully and it seemed to work pretty well; I had issues with it drifting around but I think that was my lack of control over the craft and the gusty wind.

So after tearing it apart revision two started:

Solidworks <3

So the carbon fiber has been replaced with .5 alum box stock 1/32 wall thickness, roughly the same weight but stiffer and 6061 doesn't suffer cracking issues. I do however need to check if I have any .5 box, if not other solutions will be sought but probably not going to touch carbon fiber. Thinking about it, using clamps with round stock carbon fiber instead of drilling though it would have probably worked out well. But I digress, the booms are also now .5 inch shorter and the landing legs moved closer to the center. In the last iteration they were all the way to the edge which acted as a lever amplifying forces from hard landings. Also the landing legs will be made longer so the blades are father from the ground, broke 2 already on the last bad landing...

So as soon as I can go back to the shop more laser-ing and CNC-ing the above should happen. "These kinds of parts are really simple and quick to fabricate especially with CNC gear. So hopfully the rebuild should be done in a week or two at the most.

Quad

It's been awhile since I have posted anything on this. But I have been working! (some might disagree..) So this quadcopter thing...

The classic Quadcopter.
This is something I have been wanting to do for awhile and now has finally materialized. The basics goals of this was:
1. Cheap but not cheap2. Custom frame aka not a kit build.
3. Can carry a small HD camera [goPro]

The frame is laser cut from a 1/8 delrin sheet that makes up the body and the motor mounts. The Struts are 10mm carbon fiber box from Hobbyking while the landing gear is laser cut wood; with the intent to be swapped for bigger ones when a camera is attached. The main bulk the electronics is sourced from Hobby King, and the main control board is the new KK2. And because everyone loves photos:

I also picked up an Spektrum 6 Channel Radio and receiver for control and also future projects. One more order from McMaster should provide the raw materials and fastening hardware.