Air studio review or at least it will be eventually

[sturgm]

Firstly all the views and comments are offered as is with the best intentions. I have tried to be honest in appraisals and suggestions.  However I could be totally wrong or totally right or somewhere in between.  All my views have been obtained over many years of experience consisting of many failures as well as some successes.
If any person is offended, then I apologise unreservedly in advance.
Well I thought that it might be a good idea to give you all some background about me, especially if you are contemplating some of my advice.
You can skip this if you wish as it has become a quite bit larger than I originally planned and has veered off into some strange areas.
INTRO
I first became introduced to flying model aircraft when I was eight as a result of a Christmas present from my cousin.  It was a fine balsa wood kit for a Spitfire that was powered by a rubber band and was supposed to fly if constructed correctly.
I had no idea how to construct the plane and neither did my father, but together we tried.  Aided with half of a safety razor blade from my father's shaver to cut the pieces from the balsa sheets and some quick drying glue we attacked the project with some gusto. As was my father's custom, there was no need to read the instructions as it was obvious what had to be done.
Some days later, the plane was considered finished.  A test flight in the back yard was arranged.  My mother made an appearance to the well published maiden flight.  Expectations were running high. The propeller was duly wound the required 150 turns.
The plane was enthusiastically launched by my father accompanied by excited clapping from my mother and a friend of mine who lived upstairs.
It dropped like a stone to crash some 8ft in front of my father.  This was about as far as he could have thrown the box and contents of the kit had it not been built.
The clapping had abruptly finished by now and my friend had sloped off not wishing to gloat at the disaster that had befallen his friend.  I always like Ian he really was a true friend.
I had become riveted to the spot stunned by the events that had unfolded before me.  My father was mumbling to himself about construction techniques and alike and was by now in among the wreckage (looking for the black box?).
I now burst into a stream of uncontrollable tears.  My mother was instantly at my side cooing as only mothers can do, trying the consol me.  She finally ushered me in away from the carnage that had been my Christmas present.
The next day was the post mortem.
My father had spoken to a friend of his at work who had experience of building these models and had explained to my father where he had gone wrong and was quite willing to pop round and see us that evening and guide me through the complete construction process.  Also my father, in preparation, had purchased a new kit for me to build.
My mother on hearing the news of an unexpected guest from my father went pop!  At which point they both quickly went off to the lounge where a heated discussion commenced. 
Some minutes later my father returned and said that all was fine and Peter (my dad's work colleague) would be here soon.
Peter was as good as his word.  He arrived on the dot at eight.  He was a slim man and quite a bit younger than my father.  He had a very easy manner and a level of patience that I had not experienced before as my father had quite a fiery reputation and did not really think things though.  'Actions speak louder than words' was his by line.
After an hour or two it became obvious to Peter and me where things had gone wrong.  The wings had been put on upside down and the couple of coats of emulsion over the tissue paper had added way too much weight and along with the prop being fitted on back to front the plane had been destined to failure.
Over the following days armed with a new razor blade and brisling with new knowledge from Peter I embarked on a solo build.  After about a week I had managed to build the fuselage, wings and tail.  These had all been fitted correctly and I had already had many imaginary flights.
It was Saturday and as a family we used to go the local market for the week's shop.  So I had put the nearly finished plane on top of the fridge out of harm's way for safe keeping.  It was virtually complete.  I had even glued on the tissue and had carefully flicked it with water to tighten it up before I was going to varnish it and prepare it for its maiden flight on Sunday.
All the way to the market, during the shopping and all the way home all I could talk about was my plane.  Skipping and hoping alongside my poor mother and father they must have gone deaf listening to my descriptions of construction, planning, flying, future plans and aspirations of becoming an aircraft engineer.
This Sunday was going to be the biggest event of my young life.  It just could not come quick enough.
We finally reached home and I burst in though the front door and raced down to the kitchen to check on my plane.  Into the kitchen I went, looked up at the fridge expecting to see my flying sleeping beauty.  It was not there!
Wide eyed I stared in disbelieve at the vacant space where my plane had been just a few hours ago.  I shouted out in despair 'Mum my plane's gone'
My mother was still struggling with the shopping bags when she heard my cry. She instantly dropped the bags and ran down to find me, my father followed quickly after.
All three of us stood looking at the fridge.  Where had it gone? 
The kitchen was quite small.  It had room enough for a small table and three chairs along with a butler sink.  I had many a Sunday evening in that sink having a wash down by my mother.  There were some small wall cupboards and some slightly larger floor cupboards around some of the walls and in one of the corners was a small blanket for Tiger, the family cat.
Tiger had been bought by my father at Brick lane in the east end of London for two shillings (that's 10p today). He was a rough hardened street cat a great and fearless mouser (and the odd rat).  Always happy to bring back his catch and put it on display in the house where you would least expect to find it.
As our eyes scanned around the kitchen looking for the plane we all came to a stop on Tiger.  He was curled up quite contently amongst a scattering of tissue paper and balsa wood that had been my plane.
I was speechless, wide eyed and blinking slowly in a state of shock.  By now Tiger had just opened one eye.  My father having quickly assessed the scene had decided on a course of action which included lots of shouting, animation and the cat.
However Tiger was having none of it.  He had eyed the opened door and tried to make a run for it.  Quick as Tiger was my father had seen this manoeuvre and had countered by slamming the door shut moments before Tiger made his bid for freedom.  No Escape was now available for Tiger.  The result was a foregone conclusion. It was only a matter of time.
The screams, the screeching, the clawing, the scratching and gnashing of teeth were horrendous.  At that was just my father.  You could not believe what the cat was doing.  It suddenly came to an abrupt end when my father clamped his hand on the back of Tigers neck.
Tiger was squirming and wriggling but to no avail.  My father went straight out into the yard and drop kicked Tiger straight over the neighbour's fence.  The next door neighbour was a kindly old lady who owned a rather over weight pit bull who had a perchance for cats.  Tiger, like all of the local cats gave the garden a wide berth.
I had no idea what happened to Tiger that day and the mood that I was in I did not care.  And for all you cat lovers, he did appear back a day later no worse for wear.
My father bought me another replacement kit which I duly finished in even quicker time having learned quite a bit on the previous kit.
Within a year I had built up a small squadron of these planes and regularly went to the local park to fly them.
I had also moved on to a JetX propulsion system that surely would be banned from sale these days.  It used solid fuel pellets in a small metal container.  With two pellets in the engine (a loose term here) and a fuse, one would light the fuse and retire to a safe distance and off it would go like a fire work rocket.
These little engines could be attached to the tail section of the kit planes that had been built as jet aircraft and if all went well the engine could power the jet up to a considerable height then glide back down.  At least that was the theory.
For my first flight I had enlisted my father to launch it for me over at the park. I had enlightened him as to what he was expected to do.  I would light the fuse and he was to launch it as high as he could on my command.
To protect the very flammable construction materials a small foil patch had to be strategically placed where the engines exhaust blew out.  This I had done as directed by the instructions supplied with kit.
Well, I lit the fuse and my father launched the plane on my mark and to my astonishment it soared off.  Up and up it went leaving its combustion trail behind. 
A few bystanders had by now taken an interest in this rocket propelled model plane.  After a short period of time the plane began to level out as the rocket engine began to fade and that was when I noticed that even though the engine had now closed down there appeared to be an orange glow in the tail section which seemed to be getting bigger.
Yes, it was on fire.  So much for the foil protection!  It was rapidly turning into a meteor on its fiery decent into the atmosphere.  It came roaring down and crashed in a ball of flame onto the grass accompanied by the clapping of the bystanders who quickly came over and congratulated my father on a fabulous display and wondered if we were doing any more and if so when.
My father thought this was hilarious and to this day has recited the episode at every opportunity. I, of course did not see the funny side of this at the time.
By the time I was ten I wanted a complete flying plane that had control wires so I could fly it in a circle and control the height up and down.  So for Xmas I showed my parents the model I wanted and it was arranged.  I had to be very specific about all aspects of the plane as they had no real understanding of what I was up to.  So to be on the safe side I had given them a written list of all the requirements and suggested that they should check with the shop assistant at the time of purchase.  My Mum was not really too happy about all of this as she felt that Xmas presents should be a surprise and it was not in keeping with the spirit of the occasion.  However, my persistence and agreement to perfect behaviour had won the day.
Xmas came.  I excitedly got up early Xmas morning and crept into the sitting room where I knew the presents would be laid out for me.  I switched the light on and looked at the presents all carefully wrapped by my mother.  I was only really interested in one and there is was the box containing the plane.  It had to be that one because it was the only one big enough. I scrambled over and tore off the wrapping paper in a frenzy of expectation.
I was not disappointed.  I opened the box and there it sat in all its glory with its Babe bee glow plug engine and the shiny red and yellow plastic body.  As it was about 4 am I still had several hours before I could even start it up so I turned my attention to the other presents, but after each present was unwrapped my eyes kept turning back to the plane.  I really wanted to start that engine.
The hours dragged by.  Eventually my mother came in and wished me happy Xmas and asked if I was happy with the presents.  I sure was and gave her a big Kiss and babbled away about the plane and my plans for it.  The first being the start up.
By now my father was in the room and I quickly thanked him as well and got straight to the start up.  He said it was still a bit too early and we should all get dressed properly, have breakfast and then we can sort something out.
Dressing dragged. Breakfast dragged.  Everything dragged.  All I wanted to do was start the engine.  I had by now got the plane out of the box.  Read the instructions front to back, back to front, and sideways as well
I knew exactly what to.  Fill up the engine with the fuel, check. Connect the battery to the engine, check.  Hook up the starting spring and wind up, check. Let the prop go and watch it start.
I had also checked and double checked the parts many times over but there was one thing I could not find, the fuel.  I guessed Dad had put it somewhere safe as it said in the instructions it was very flammable.
Time had been ticking by slowly and I had been hoping about all over the place pestering my Dad about starting.  Finally at about eight a.m. he agreed and off we went to the yard for the test start.
I got everything set up and then turned to my father and asked him for the fuel.
'What fuel?' 
'For the engine' I replied.
'Ah, he said I have got some in the cellar I will get it for you.  I won't be a moment.'
The so called moment dragged on and on and on.  I was starting to get worried.  Then there he was there with the bottle.  I grasped it with both hands as though being given the elixir for eternal youth.
Funny looking bottle I thought, it looked like a medicine bottle, but I opened it up anyway.  I knew that smell it was petrol.  So I ask Dad where he got this from.  He informed me that he had just got it from his cars spare petrol can.
'But I need Glow plug fuel.' I pleaded.  'This will not work at all. Where is the can that the shop gave you when you bought the plane?'
'What can?'
The reality of the situation was starting to dawn.  It was Xmas day. I had my dream plane.  I had everything to start the engine except the fuel.
Despair flooded over me.  Should I try the petrol? It might work.  I was a ten year old getting desperate.  It was worth a try, wasn't it?
At this point the bottle was whisked away by my father with the parting comment of 'Oh well you won't need this then'.  Luckily for me he did.
So, for two days I sat and stared at my fuel less plane and wondering what might have been.
On the day after Boxing Day my father and I were waiting outside the model shop for it to open along with quite a few other fathers and sons, but we were first!
The doors opened and we all trooped in I asked the shop assistant for a can of glow plug fuel.
'Sorry son I cannot sell it to you as you are not old enough' he replied.  I could not believe my ears all this way and I could not buy any.  All this time I had spent counting the hours at home, waiting for this very moment. I was just about to go pop.  Then in the corner of my eye I noticed that the assistant had been winking at my father who had a wry smile forming on his face.
We left the store (and the funny ha ha shop assistant), to my relief with a full can of glow plug fuel.  Life was certainly looking good for me now.
After this hiccup in events we went home.  I started the engine and it ran well.  We then went over to the park to fly it.  It did fly as expected, in circles with me getting somewhat giddy.  All in all it was a bit of a disappointment.  Flying a model plane around in circles on a long string was not really fun at all.
Fast forward 30 years.
I was by now a very successful freelance computer consultant/programmer with an engineering background writing trading software for a very profitable merchant Bank. 
I had first started programming in machine code on a 6502 processor many years earlier as a bit of a hobby. I was like a duck to water.  It just seemed so easy.  I rapidly moved on to other processors Z80, 80286 etc.
I had also written a popular game for the Commodore 64 but had used a 'nom de plume' of Clarke Kent (cheesy I know).
Then one day my eldest boy Paul had come home from school looking a bit sad.  I asked him 'Why he had such a glum face'.  His reply was that I had just cost him quite a few free drinks and sweets.  How?  Well it seemed that one of his school friends had bought a new game called 'Star Command' and Paul had been invited round to play it.  On seeing it he said that I had written it.  His friend said that is was not possible because it had been written by 'Clarke Kent' and 'Kent' was not Paul's surname.
OK how does that cause you the loss?  Well, If they had believed me I would have had such 'street cred' that everybody would have wanted to buy me drinks and sweets!
I also began programming in high languages such as 'C'.  I started getting commissions to write device drivers for UNIX and the fledgling OS from Microsoft called Windows.  After some time I decided to 'throw my hat in 'with Windows and ease off on the UNIX.
As the years went by Windows was in the ascendance and my skills were in great demand.   Then by chance I came across an article about radio controlled model helicopters and what advances had been made with modern solid state gyros.
Then all the deeply hidden desires came flooding back, I had to have one.  This time, however I may have been cash rich but I was time poor.  I still found time to make some enquires and tracked down some stockist and made the necessary purchases to start the build.  If memory serves, I think it was a size 36 heli (Riobo?) with a nitro engine.  I even bought a SIM which was quite disappointing but 'par for the course' for those times.  It was so blocky it was like a cross between Pac man and Teletext.
I managed to squeeze in some time over the months to build it.  The Internet as this time was in its fledging days so there were only books and phone calls to stockist for help on setup problems.  I had considered joining a club but never did for one reason or another.
After many crashes and phone calls for parts, I finally got it in the air for long enough to embark upon setting changes.  I was fortunate enough to own a house with quite a bit of land so I literally stepped out the back door into a field.
I was still having the occasional crash and I had the stockist on speed dial. We were on first name terms by now and a 20% trade discount.
This adventure had cost me Thousands.  I must have bought enough parts to build ten helis over the months but it was fun and I needed that as the work was starting to crush me.
I stilled loved the coding but it was the politics that was stifling.
My wife and I had a chat and I was going to end the contract and retire.  The guys on the trading desk had other ideas.  They really could not understand why being prepared to pay me any sum mentioned I would still want to leave.
As one of them sardonically mentioned 'The only way we will let you leave is in a coffin'.  I manage to negotiate a six month notice period with a further six months of home support.
The discipline that coding in that hot house environment instilled was second to none.  There is nothing like the stress of a real-time system failure with no back stop loses in place.  It really does crystallize one's focus when the desk stands to lose £10,000 per second.  To get things into perspective, in those days you could buy a nice detached house for about £35,000.
After leaving work I started to concentrate on my two hobbies.  Woodworking and Helis.  Over the next few years I bought all number of helis right down to the tiny MXCP always being amazed at the miniaturisation that was available.
Then I discovered Quads.  I was drawn completely in by the thought of being able to write code that could control these wonderful flying machines.
You, dear reader, may be thinking why are we here?  What has all this to do with a flight controller board?
Broadly speaking, everything. In over 30 years of coding certain ideas and concepts always rise to the top and cannot be disputed, discussed maybe but will never alter. The average phone these days has more computing power than any of the systems that I worked on the early years.   However the rules do not change.
The code had to clean and well documented so ANYBODY could pick it up. Variable names must represent usage and type. Source control was strictly monitored and adhered to.  Any code had to be peer reviewed and tested to destruction.  This sadly is not the case with open source code.
I have worked on device drivers that had read printer ports via interrupt code and I only had 73 clock cycles to process the port before returning.  I had an ICE plugged into the CPU socket and had to calculate the clock cycles each instruction took and hand code the routine in assembler.
On the other end of the scale I had to write a DLL to interface with an Excel spread sheet to calculate the value of a German Warrant in real-time in under .01 seconds
Here are a few things to consider. As in 'Strictly Come dancing' parlance 'in no particular order'.
(1)   Firstly no matter how good the hardware is, it is the code that makes it tick.
(2)   Poorly written code on next generation hardware will most probably NOT out perform quality code on legacy hardware.
(3)   A port of code from one CPU to another should always be considered a stop gap, not a solution.
(4)   If common components are used on different supplier's boards there will be no difference in performance if the same ported code is used.
(5)   A higher clock rate does not guarantee better performance.
(6)   The way forward for true improvement is interrupt driven code.

The review starts here
Why did I buy the board?
There are a few reasons.  The sensors are on a separate board and the quality of the individual sensors was of a good standard.
I have pasted below excepts from their web site
Flight Control Set feature list
   Stabilized flight modes for different multicopter frames (Tricopter, X4, plus4, Y6, Hexacopter, Octocopter, X8);
   Integrated On Screen Display (OSD) for First Person View (FPV) flights
   GPS for position hold, return to home position and loiter (GPS position hold)
   Magnetometer (Compass) for heading determination
   Very precise Barometer for altitude hold
   Automated waypoint navigation using ground station software
   Mounted camera stabilization and shutter capability
   Specialized Power board for power distribution and current measuring
   User configurable LED output with possibility to inform about low battery
   Capability to use any R/C receiver
   External signal module (Status board) for visual summary of aircraft condition
   Optional:
   Sonar sensor for automated takeoff and landing capability and altitude hold (till 5m height)
   Wireless telemetry for long distance communication.

Air Studio Control board is MegaPirateNG and MultiWii compatible hardware with ATmega2560 and some additional features:
   Dedicated output pin for high current load up to 8A (LED strips, etc.)
   Third output (besides Pitch and Roll) for camera gimbal that can be used for camera Shutter control
   Integrated OSD controller with LM1881 sync detector that is compatible with DIY OSD and other open source OSD software that can use ATmega328P.OSD has serial connection to main controller for receiving sensor readings
   Integrated voltage divider for battery voltage measuring up to 4S LiPo, input for current and RC receiver RSSI measuring

Control Board Specifications
   Input voltage: 6-18V
   Current consumption at 12V:
   Board only: 40mA
   Board with GPS, IMU, sonar: 80mA
   Switching voltage regulator for reduced heat dissipation.
   Operational temperature: 0C - +60C
   Dimensions: 50mm x 70mm
   Mounting holes: 3mm diameter, 45mm x 45mm
   Receiver channel count: 5 to 8
   Motor count: up to 8
   Camera gimbal outputs: Pitch, Roll, Shutter
   Output for high current load (LED strips): 8A

GPS Board Features
   MediaTek MT3339 66 channel GPS chipset
   Dimensions: 38mm x 17mm x 8mm
   High sensitivity: Up to -165dBm tracking
   Position accuracy: &lt 3m
   Maximum update rate: up to 10Hz
   Time to fix:
   Hot Start 1 second typical
   Warm Start 33 seconds typical
   Cold Start 35 seconds typical
   Very low power consumption：25mA acquisition, 20mA tracking
   Power supply: 3.6 - 16V
   Built-in supercap for RTC backup power to decrease Time To Fix after power reconnection
   Built-in patch antenna for reduced size
   Serial TTL Interface with default baud rate 38400 bps
   NMEA and Binary protocol
   Includes cable adapter
   Weight: 10 g

Sense board contains
   ITG-3200 gyroscope
   BMA180 accelerometer
   HMC5883L magnetometer
   MS5611 barometer
   logic level converter

As can been seen from the above the quality of the parts and the separate boards is most probably better than most.  However the specifications of the actual components are only equal to most of the other budget boards available on the market.
The onboard OSD is a real extra, along with the power board which enables an installation that does rely on a supply from one of the motor BECs which can be quite noisy.  However the GPS module is not up to the latest CN-06 V2 U-blox set that can get position accuracy to 13cm (yet to be confirmed).
As I mentioned early in the document most (if not all) FC boards use the same primary components and are compatible with the two major code sets available (Multi Wii and Mega Pirates).  So in essence, what is there that separates this product from the pack.
Even taking into account what you get for the complete set price it still is expensive. But, for me it was support and documentation.  They always answered any queries promptly and with usable answers and the modified code sets supplied worked with no further modifications.
The installation documentation offered was superb and the fitting into my air frame was simple.
Would I recommend it?
This is a bit tricky.  If you want to just fly a quad out of the box then any flight controller board is not for you as you should buy a finished kit from a reputable value added seller.
If you want to get your hands dirty then maybe.  But how involved do you want to become?  Modifying code and uploading it into a board can be a problematic and frustrating process as well as costly.  I can a test to that having bricked my first FC (a BV board) into a piece of junk.
You may also want to take a more middle of the road approach by buying a proprietary coded product that should work out of the box but at a higher price.
This now raises an interesting point.  What is the difference between the hardware on say the DJI Woookong boards compared to the cheaper FC boards?
The simple answer is nothing much.  So how do they achieve such levels of control and accuracy above and beyond the cheaper boards?
Software, produced by a team of in-house programmers who follow the same time served rules of software development is the answer.
It may seem harsh, but Open source software produced by well meaning like minded individuals can not consistently produce, release and support quality product to match that of a professional software house.
I have great admiration for these people and it was this aspect of the hobby that drew me in.  That said, after many months of trawling around the internet and inspecting the code produced I came to the above conclusion. It is a shame as I always felt that I could add some value to code base but it is not to be.
A good example of this is a feature called Alt Hold.  Look at any video of a DJI Woookong quad displaying this feature and then compare this to even the best of the rest.  Yes the OS people are getting better.  Yes they are catching up, but there is the truth of the matter 'catching up'.
So what exactly would one expect from a 'new' FC board with the same components and the same variant of software.  Much of the same.  So what actually is being reviewed?
In conclusion.
This article is most probably going to upset some people.  All I can say in my defence is that it is only my view of the current situation after doing some more research.  It will change over time as all things do.  I originally had no idea that it would end like this but there you go.

[Gaza07]

Another very well written story I enjoyed reading it thank you for posting 
the only thing I would say about this controller is the sensors are out of date and the AIOP has the newer 6050 gyro/acc for a lot less money although it doesn';t have the built in osd 

[sturgm]

Hi Gaza,
Thanks for the comments.  I know it turned out a bit long in content but I enjoyed writing it.
As regards to the board.
Early on in my programming career when PC';s were not as ubiquitous as they are now.  I was always asked what PC should I buy and was it a good time or should they wait for the newer model.
My advice was simple no matter how long you wait to buy your chosen setup, tomorrow it will be out of date.

Mike