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I've been traveling around the world the past couple years and on/off of it's occurred to me that it'd be great to have a drone to get some of the crazy shots at especially scenic locales.

The latest generation of consumer drones are almost there - the Phantom 4 and (to a lesser degree) the Yuneec Typhoon H PRO have decent image quality in a small package (1.4kg, 2kg respectively). As a photo/video geek however, tiny sensors with middling dynamic range, rolling shutter, and substandard bit-rates rankles. Having the flexibility of mounting a higher quality payload like the BMMCC, or a 360 solution like the 360fly 4K would be much better.

The tradeoff for DIY drones is that while adding payload flexibility (and a potentially better travel form-factor), they seem to have fallen behind AIO devices in terms of flight/camera automation.

$1399 - Phantom 4 Positives:

• A very nice phone/tablet UI that includes smart drone and camera control as well as video.
  • Tap to fly
  • Optical object tracking (ActiveTrack)
  • Orbit mode
  • While it doesn't have explicit "cable cam" modes, you can course lock and set waypoints and manually control the gimbal
• Lightbridge is a 2.4GHz digital Wimax-like protocol that advertises 5km range and does integrated transmit, telemetry, and video (220ms latency)
• Has stereo-optical frontal sense and avoid and active obstacle avoidance
• It also has a downward facing camera and ultrasonic sensors that give it best-in-class low-altitude hover
• 1.4kg flight ready
• Quick release rotors

Phantom 4 Gotchas/Mods:

• Replacing landing gear - the form factor isn't ideal for strapping on the back while hiking, this, and landing gears in the shot can both be fixed by replacing the default skids w/ retractable landing gear (see also: 1, 2, 3, 4, 5, 6)
• The gimbal/camera is quite complex looking, hasn't been reverse engineered, you're likely stuck w/ it
• You can probably take the Phantom apart and weatherproof it (CorrosionX everything); it may be possible to replace the lens

$1899 Yuneec Typhoon H Pro/Realsense:

• Sadly, it's almost not worth talking about this because while there are a many good things, the camera is terrible - it shoots a mystifyingly low bit rate (29Mbps vs the Phantom 4's 60Mbps) and doesn't have a true flat profile. The default lens is super-crappy and focused improperly, so if you buy one, consider a lens upgrade mandatory.
• The Typhoon H is a hex, and can fly if a motor/prop goes out. It also has quick release rotors.
• It comes with a retractable landing gear and allows 360 motion on the gimbal out of the box, but that doesn't help portability much - the arms fold down, making a big cylinder that's probably not the most convenient thing to carry.
• The ST16 controller is quite large, but integrates an Intel Atom touch screen system into the controller w/ 1080P transmission w/ <200ms latency all via a custom 5.8GHz (802.11ac-like?) protocol (1.6km range)
• It uses front-facing ultrasound and Intel Real Sense camera for obstacle avoidance
• Camera modes:
  • Orbit Me
  • POI
  • Journey (selfie)
  • Curve Cable Cam (preset curves for flight and camera position via waypoints)
  • Watch Me/Follow Me (GPS)

And of course, there's the DIY Drone option. I will probably end up here, since I've started going down the rabbit hole here, but some thoughts.

First, portability is the pretty key here. Although flying weight will probably be a bit heavier than the Phantom 4 (just over 2kg), we can build a drone that can lift over 1kg of payload that packs up to about the size of an A3 piece of paper using an Alien 680 frame (Skylark, H4/H4).

Above is what it looks like folded up

The foldable props are particularly sexy.

For travel, separate servoless retracts is probably the way to go, but life may be easier w/ some known standard retracts.

We're of course responsible for our own camera/payload here. I have a Point Grey Grasshopper 3 lying around that'd be worth trying to get to work. Notably, it has a Sony IMX252 sensor which is FHD+, 120fps+, has a global shutter, and about 12 stops (72dB) of dynamic range, far better than the DJI/Yuneeq cameras assuming I can get something reasonable to record with (ideally an XU4, MinnowBoard MAX, or less ideally, a TX1/J120).

In addition to that we'll need a gimbal. Variations of the Alexmos/SimpleBGC controllers seem to be the most common/well known. This undoubtedly requires some more research, but there's no end of control/programmability there.

The same lightweight gimbals should be usable for mounting something like the Fly360 4K.

Gimbals that can handle heavier setups (BMMCC, other m43 cameras) are more expensive and heavier, but should be doable. (if my eCalc numbers are accurate)

You can of course spend a lot of time working on the power train. I'm almost tempted to buy some motors and a testbench simply to confirm some of these, but there's no point over-optimizing before doing a build, I suppose.

Lastly, and most importantly perhaps are the navigation bits.

There's plenty of 915MHz telemetry modules that are quite cheap, although it might be worth considering a DragonLink for ridiculous range, handling the RC transmission, and bt connecting to handhelds.

The UBLOX M8N GPS modules seem pretty standard and can be bought for dirt cheap (cheap one w/ EMI protection), you might benefit from a really large pro version (or an expensive smaller one) - there's a tiny comparison here. For those serious about their GNSS it looks like Emlid's Reach is pretty cool (DrotekandPiksi are two others)

For the Pixhawk flight controllers, two good options look like the PixRacer which has slightly newer sensors and built-in wifi, and the PixFalcon which has a failsafe mc and some extra power filtering. Both are pretty tiny.  (I'm still researching whether it's worth going with the newer RPi-based controllers like the Erle-Brain 2 and Navio2 - right now it may be better/worth it to simply connect a separate board via MAVLink for more complex stuff, but have a more reliable mc for basic flight controls).

My initial plan for video transmission is to use an analog 5.8GHz transmitter w/ HDMI support, but the Amimon Connex Mini looks pretty darn cool (1080p60 @ 1ms latency, 500m range).

Ultimately, I'd like to primarily use autopilot/telemetry for most of the flying, and at the very least reduce radios (the DragonLink would combine the telemetry and RC control), but RC control, at least for a backup/emergency is of course required.  This is probably it's own project, but it seems like it'd be possible to build a tinyduino/PPM+receiver+minjoystick 2/4-channel doohickey.  Until then, a janky $15 controller might be the most compact option.

Obviously, just about everything for this setup requires some work, but the big projects for me would be:

• optical-flow/object tracking/gimble movement (optical follow me)
• gimble/camera direction waypointing (curved cable cam)
• laser/sonar obstacle avoidance/stability
• fly-by-telemetry (radio/control reduction)

For those interested in a parts list/notes:

https://docs.google.com/spreadsheets/d/1TkPLaImvb76bMIvJKKhjp9y2UGUzCGRrSXMRtdTIkas/edit#gid=0

My plan is to start putting some of this together when I get back in the US in Sept/Oct