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A "wearable" UAV/FPV GCS with a twist

Here's an update to our handheld (or rather body worn) modular commercial/civilian UAV GCS, an all-in-one FPV system with a fully functional integrated PC telemetry head. This is something that we've had in the works for some time now, but only as a nice concept and some sketchy plans. Since one of our old clients has been pushing us hard for it, we had to put our CAD design into a tangible form eventually at the beginning of this year.

Even though our modular FPV tray system has become a very successful product with many working configurations and options, mounting a PC in it or over it was hardly a trivial task. We've been offering our own separate rugged telemetry system in the same Peli 1400 format as a companion to the belly box, so we knew what we were up against when we wanted to go even further.

On the one hand, we were very much aware of the weight issues that may arise with the number of functions we need to include. The telemetry PC needs a complete support frame, a practical user interface, brings the necessary RF modem into the tray, and it may have a huge impact on total battery endurance, all resulting in added weight. This will also affect console balance, which is a very important factor with all types of belly boxes, because you need a stable tray to control both the direct RC and the PC GUI with precision.

On the other hand, such a high number of electronic and RF systems in close proximity can cause havoc in both interoperability and interference. On top of the three obvious RC/AV/modem RF bands there are also some additional radio modules working in the PC. Of course WLAN, BT and NFC can easily be turned off in the field, but the embedded 3G modem is pretty handy for on-site live map services, and there's also a GPS in there. Depending on how you count them, we are talking about 10-12 different RF devices working close enough to bust each other's LNAs or end stages, even with their out-of-band or spurious emissions.

Anyway, the weight and balance issues never really cropped up, and we could use the same old folding brackets we made for the original control tray. We could mount the unit on the cross-over strap without a hitch. Even though the fold-up frame, its internal support and the PC adds some 700g to the set, you don't feel the difference, even after several hours of running around with it.

Probably because of careful module placement, adequate filtering and possibly some luck we haven't run into interference or loss of range issues, either. The current production sets are running with UHF LR RC, 868-915MHz telemetry and 5.8GHz AV in such a small unit, but we've also tested the same telemetry/AV combo with high power 2.4GHz RC without any issues.

The embedded tablet PC has a Z3740D Dual Atom CPU, 2GB RAM, 32-64GB RAM + micro SD card slot, 8" IPS Display with 1280 x 800 resolution and 10-point capacitive touchscreen, but it also works as a digitiser for even more accurate waypoint programming. It runs Windows 8.1, so Mission Planner and other standard GCS sw are there in your lap in full function.

In addition to the usual WLAN and BT modules, it also has a built in 3G-4G modem and both front facing and rear cameras. We've added a matte and low-reflectance (the two are not necessarily the same!) screen protector from 3M, to make the otherwise really high nit and high contrast panel even more sunlight readable. We have left both the SIM card and the micro SD card slots accessible, and we have also added a full size USB socket in the tray.

Adapting such a small piece of tablet hw has its own caveats, so, apart from toughening it up mechanically, we had to solve simultaneous OTG USB and charging, too. This is done through a single connector on the base for both the control tray electronics and the tablet. Despite the slightly higher power consumption of an embedded telemetry modem, battery endurance is still around five hours for the control tray. Since the tablet has its own battery, we have left it to its own devices for now, which will take it over the eight-hour mark easy, especially because there's an active powered USB hub for the peripherals.

For those in favour of lighter IT packages, we also have the same station framework with an 8" Android telemetry control head. Not only is it much lighter and still totally waterproof, it's also a bit easier to operate via touchscreen than Win8.1 systems. As DroidPlanner and now Tower is getting more and more mature as an all-round GCS sw package, I think the future is bright for both platforms.

Thanks for your kind attention,

Azjeg

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