Death of a Flying Wing
The FPV wing I built with my CNC hot wire foam cutter didn’t last very long. I added a HobbyKing 3 axis gyro to it and it felt very strange on the first flight and then disaster on the second. The wing flew OK before the gyro but not stable enough for FPV, I tried it and it was a bit scary. So I thought adding the gyro would help. On the second flight launch will all the gyros turned down to zero it went off intially OK and then did a nose dive straight into the ground with no amount of up eleavator making any difference, it was a write off but luckliy my FPV camera and transmitter survived So back to the drawing board and this time a HobbyKing EPP-FPV with ArduPilot (HKPilot 2.7)
The HobbyKing EPP-FPV – ArduPilot/ArduPlane
I wanted a Bixler but couldn’t find one anywhere in stock and so after some more research I went for the HobbyKing EPP-FPV but this time I’m going to add and APM (Arduino Pilot Mega) for the safety features it will give me, such as RTL (Return to Launch) and Geo Fence (won’t fly outside a given area). Its a big plane and from the videos I’ve seen on YouTube it looks just the job.
I’m going to use this complete kit from HobbyKing HK Pilot 2.7
I highly recommend watching this video series by Painless 360 APM Flight Controller they’re outstanding and high quality from guy that really knows his stuff.
Plan will be ;-
- Build the plane first without any extra equipment and get it trimmed out for stable flight.
- Add video camera and transmitter and check picture is OK on ground station
- Add the APM and check its function OK, this will probably take a few flights
- Fly FPV
I’m going to document the build and installation so it may help others. Seems to be quite a lot for quad-copters but not as much for planes, The main resource for this is at http://plane.ardupilot.com/ So as I progress I’ll update this page
The build of the EPP-FPV is very easy and the instructions quite good. I used 5 minute epoxy for for all the joints and Hobby King 9 gram servos. I’ve also glued a small piece of lite-ply on the nose section to mount the the Mobius action cam and the Sony TVL 600 FPV camera. As a precaution I’ve fitted a rubber band on the nose section piece even though the magnets seem quite strong. The maiden flight will be without any FPV or APM to get the model trimmed and get me use to flying it. FIrst attempet to maiden was aborted because it was too windy, so just the pictures below at the Rotherham and District Model Flying club
Maiden flight was OK but found it better to add some rudder in the turns. The centre of gravity is way off in the manual and I’ve balanced it on the main spar. Flies much better now. HK Pilot 2.7 is a bit of a squeeze as the fuselage is not very wide, have set it on the CG and tested it was showing level on mission planer when the plane was on my CG balancer.
Installation of the APM
Installed a liteply support for the APM and mounted so it was right on the C of G. I used CPPM from the OrangeRX receiver so I only had 1 lead going to the APM. The GPS I mounted on the wing on some Velcro so it can be detached. Took quite a bit of time to understand the set up and Mission planner but its worth the effort.
The APM controller is no longer being developed so the latest firmware for arduplane is 3.4.0. This is because it’s 8 bit technology and the developers have reached a point where they have no more resources available.
Don’t be put off by this the APM is very mature and still does a great job
First flight with APM
Took off in manual mode everything worked as expected. Switched into FBWA and this really smoothed out the flight and then tried RTL(return to launch). Was really amazed how it throttled up and flew circle around the launch point.
I then decided to try FPV which was a bit strange but I knew I had RTL to get me out of trouble. I flew around for a couple of circuits and then went back to line of sight. Camera needs to pointed down a bit next time, The video in my HobbyKing Quanum V1 headset is OK but I’ve know invested in the V2 which seem a lot better.
I’ve set up and Mission to fly a circuit around the field and plan to use this to help flying FPV so I can get use to the view from on board.
Minim OSD woes
I had lots of issues with the OSD and have fried 3 of them. I think I finally have it sorted. The only one that seems to work well is the V1.1 with the firmware listed in the link below. I tried a later version and one from eBay. Sometimes they wouldn’t boot and one of them as soon as I applied throttle the video was lost. I’m using the https://code.google.com/p/minimosd-extra/downloads/detail?name=MinimOSD%20Extra%20Plane%202.2.hex&can=2&q= which is the latest stable version.
This one fried as well.! This time I’ve carried out the 5Volt modification but first practiced the soldering on one of the fried OSD. Here’s a link to the way to do it https://www.flitetest.com/articles/rctimer-minimosd-5v-mod . I purchased these magnifiers from Amazon and used a very small soldering iron and it was really easy to do. The magnifiers are brilliant and I used them on lots of other jobs since. Make sure you don’t connect the 12Volt red wire on the video in and out connectors just join them together and apply some heat shrink.