Partner's comment repost

[This is a comment from my partner, reposted as a post as he forgot the password to the blog, as it is somewhat important]

It’s probably about time that I say something, so here goes.
In terms of actual progress the completion of phase 1 was a pretty fulfilling experience seeing as it really pissed me off in its initial stages. The transgression into phase 2 is just as my colleague says; in its infant stages whereby the physical airframe needs to be constucted from twinwall, sintra and cabon fibre alike.
If I decide to grace this blog with my presence at some point in the future, and thats a big IF, i’ll probably be updating this progress sheet with intel on the electronic side of the project.
At this current moment in time the autopilt system is to be installed using the ardupilot system. I have recently come into possession od the various processor boards, GPS Modules and airspeed indicators but for the time being it seems that the airframe is going to require more attention.

And that’s about it…

So long.

Phase 1 redo

Due to numerous problems, I had to bring home the Mugi to fix several things, namely the pushrods, the servos, and try and get a better cockpit configuration. So far it's all gone well and the promising first flight is within reach - its rather annoying its taken so long to get here, but being new to rc planes I feel we have learnt many invaluable lessons, one of which is battery care (having possibly avoided an explosion!).

But everything has been fixed, and now I'm just waiting for Tuesday so we can get a proper flight going, having ordered a new battery charger and transmitter battery for monday. I finally took a couple of pictures:





Whilst I'm busy fixing the Mugi, P has been working on the airframe for our Phase 2, with emphasis on stability, and repairability. We've come across a good design from diydrones.com and, with some modifications, hope to use it for our project. We're still working on constructional techniques and exact dimensions, but we're thinking about 1.5m wingspan, and a 0.7m fuselage connected to a tailplane by two rods.

Nearly there...

We had all the parts. The equipment was set, and we ventured onto the nearest patch of grass, only to be beset by the fact that after a horrific nosedive after a self launch, it was discovered the antenna had in fact snapped. By the time we had soldered everything back together, there was no more time - and thus, for the second time, we were cheated of our promised maiden flight.

The good news is that the pre-flight checks looked promising. The ESC that arrived needed some modifications before it was fully functional, as we had to replace the seemingly faulty push switch (and it didn't behave as we expected either) with a SPST toggle switch. The battery also had to be modified, as I had to split the power supply (not sure if this is an altogether acceptable thing to do) to power both the receiver and the ESC, but after that, the prop worked wonders, spinning furiously (and at one point coming off and nearly taking someone's eye out), and the elevons responded nicely. The centre of gravity seems to be in the right place, but the motor is a bit loose (but the line of thrust is correct, as we see it).

The maiden flight will have to wait until after the holidays unfortunately, but we will begin phase 2 in January as well (hopefully), after we get the results from flying with the mugi.

The final part

The ESC arrived yesterday, completing the puzzle needed to finish the project. We had to solder in some home-made connections to due esc having a battery connector from Hong Kong that did not fit, and the fact that with only one battery, we had to split the power supply (obviously this would result in reduced flight time, but we hope to obtain another battery soon) - but in the end, it all fitted together nicely.

We were rather surprised by the power of the motor, after its feeble performance a few hours earlier. We did some electronics test, and the servos and the esc worked as they should - the servo jitter is still a nagging problem, but we don't exactly know how to fix it yet.

We were about to launch it for its final test flight, before the battery gave up on us (though checking the centre of gravity and the general aerofoil shape, everything should progress smoothly. Hopefully the battery will be ready to go tomorrow after some charging, and after I fix the slightly off-centred elevon, the Mugi should work like a dream.

Clevis fix

I managed to remember to bring in the clevis today, and after breaking yet another one, we managed to replace the old broken one, thus restoring good control and balance, and synchronisation to the elevons. Now all we need is the ESC, with which we can do some test flights and establish a good aerofoil for the Phase 2 aircraft.

Arrival of parts

Today I happily recieved the new clevises in the mail, along with some more twinwall sample material, and a rather interesting letter. This should speed things up a bit and allow us to finally synchronise and smooth out the elevon movement on the right wing, after my little crushing incident. The shipping status on the esc states a friday or perhaps saturday arrival (hopefully)

P has also obtained some Sintra, with the hope of creating some cross-sectional shapes for the fuselage and the wings, for Phase 2, and that will definitely be useful. I'll just have to investigate weight issues and decide whether twinwall really is the best material to use. Since our aircraft will not necessarily be flying at high speed, and maximum efficieny as well as stability is crucial, so an aerofoil with some camber and high lift at low speeds would be ideal.

UAV initial thoughts

This will be where progress is logged.

We have a contingency plan consisting of several phases. Phase 1, at this point in time is nearing completion, as the Mugi Evo is nearly finished. It was mostly assembled kit, but so far it has helped us understand the basic control features of the plane ans well as transmitter programming, both essential for an autonomous vehicle.

So far, progress has gone well, with few upsets - the plane is now only awaiting a new clevis to attach the control rod to the servo, and a brushed motor controller to control the motors. We also need to find a way to attach the battery to both a servo lead as well as the standard battery connector.

Both are crrently being shipped in, with a total of approx 110 pounds spent on the project already.

Just so you know what Phase 1 will attempt to look like, here's a picture from the manufacturer's website.