Last week I spent an entire day trying to sort out my Iris+ with Tarot gimbal / Go Pro setup. Yes, it's supposed to be plug and play. And it sort of was. Just not play properly. The issue I had was widely noted on the net: the camera / gimbal 'shuddered' and would not hold a position. Generally I could get it pointed straight down, or straight out, but nothing in between. And then in flight, it would randomly switch between down or out angle - perhaps it thought it could choose the camera angle better than I could! Indeed, there were some nice horizon shots!

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​So back in the lab, I went back to the beginning to install and configure the gimbal. The reason I wasted so much time was because some of the websites that I visited had incorrect advice. Imagine that!

Rather than write an entire user guide, I've collated what I found out to work for me:

How to install the Tarot gimbal:
This is the best site to use. There are several, many with incorrect advice (including the 3dr official site!).

Make sure that you get the gimbal connection right! The connection shown here in step 3 is INCORRECT. The black wire needs to go to the pin on the bottom right of the picture, not the middle one. Thanks 3DR, this was one of my biggest problems - in this configuration the gimbal would not respond to the RC after the firmware upgrade at all. Weird that it responded beforehand though...

If the gimbal shudders (mine did!), upgrade the gimbal firmware as per above best site. Note the importance of NOT connecting to the power source until AFTER you start the upgrade. Weird hey. It's shown perfectly in the video below.

When trying to configure the gimbal, if you get a prolific USB to serial error, follow the directions on this page. I tried links from other pages as well but they didn't work. This was definitely the best one.

Once you've done all this, if the camera is not pointing in the correct direction, you need to re-calibrate it. Point it straight upwards towards the belly of the platform. Click on 'calibrate sensor'. This is shown in the video below as well.

If I had used the ardupilot wiki in the first place, then I would have saved myself a lot of time! For those sifting through the sea of advice on this matter, hopefully this confirms for you which recommendations to follow.

This morning I headed out to do a test flight with the 3DR Solo. I have to say - I was suitably impressed!

We flew with a GoPro in fixed position, rather than using a gimbal, so I can't comment about gimbal stability. But I liked the way the camera could be easily moved from looking outwards to downwards (pre-flight), while still feeling like it would hold its position during flight.

Some of the features that I particularly liked were:

• The box it comes in! Nice and sturdy, one of those ones that you don't want to throw out. Which is great, because it will do the job for transportation until you figure out which Pelican case or similar you need in the longer term
• The batteries. OK, propriety is a bit of a pain, and they are rather expensive, but their charge is easy to check with some lights on top, and they click in so smoothly to the upper body of the platform
• The centre-default throttle, which is great for holding altitude
• The integrated tablet holder, so you can use the Tower app at the same time as flying (annoying the app is not for iOS though)
• Flat propeller profile - makes them easy to pack away
• As with the Iris+, the idiot proof set up with the propellers having matching colours and icons to show which way to turn them to tighten - even my 4 year old can set this up without instruction
• The information screen is really easy to read and informative! Even with polarising sunnies on, it was super clear to see
• The option to add different payloads is a huge plus. We're looking to integrate a spectrometer, so I'm definitely keen to put this to the test
• Changing between manual and automatic flight is very easy with the Tower app. I definitely recommend two operators though. 'Unmanned' airborne vehicle is a bit of a misnomer!

There are only a couple of minor things where there is room for improvement in my opinion:

• Would like to see the front and back of the platform in different colours like the Iris+. The lights can't be seen during the day, so it's impossible to tell which way it's facing. Having said that, coloured or not, it's nearly impossible after it gets a little further away anyway, so I guess this isn't big issue.
• I felt a little limited with the flight modes. I'm used to being able to flick a switch to change between loiter and alt hold, then RTL for example. That could be done from the tablet but I don't want to take my eyes off the aircraft and controller to switch. Might just take some more experimenting.

With the fixed Go Pro, I flew for approximately 16 mins on a single battery, landing at the recommended 20% charge. There was a light breeze and I wasn't really working it hard, so I expect that this is the upper limit of flight time.

Two years ago I bought a dJI s800 for a complete package of around $10K. It came in a dodgy half broken cardboard box with no balance charger or power supply. Yet it was considered 'ready to fly'. The batteries allowed for five minutes of flight time before four hours of charging. Flight planning was difficult, and it was near impossible to extract the telemetry details post flight. The technology has come a long way since then!

The 3DR Solo is certainly 'off the shelf' technology that can be purchased from Harvey Norman or similar. It set my colleague back about $2K for the platform, spare battery, android tablet, and Go Pro. Certainly a worthwhile investment for extending field survey range, and scaling up to satellite data.

There are a heap of other features that I didn't check out in this preliminary test. But it certainly exceeded expectations in the areas I considered. They have clearly done a lot of work in making the design as polished as possible, and it has paid off with user experience. This really can be used by a complete novice. CASA has an interesting challenge ahead to deal with regulation against increasing accessibility of these devices.