Garage Drone #3

Removing the ballast but leaving the top-plate in place, glue the next set of spars to the plate in the same way as previous.

As this plate is no longer available to distribute the pressure of the ballast, I have used a trolley to the same effect.

Wipe the edges with a solvent shortly afterward to ensure the upper "quad" assembly does not get stuck to the lower.

Garage Drone #2

Use the top-plate of the same dimensions as a spreader in order to apply pressure to the first application of adhesive but DO NOT adhere this top-plate to any of the parts at this stage.

Garage Drone #1

On a clean and flat surface lay out the base-plate, in this instance formed of aluminium of dimensions 500 x 500 x 1.5 mm.

Arrange the spars as shown ~ here measuring 1/16 x 1 x 2 x 39 inches ~ and mark up with a felt pen around the margins and the length of each spar as a guide to preparing the surfaces to be joined.

They should then be joined by a suitable epoxy and the choice is between a long cure suited to metal, or here a fast-setting mix to expedite. Super-glue might yet be tried and is likely to be equally cost-effective whilst altogether faster.

Effectively however this process serves mainly to locate the parts, as the plate and sections will be pop-riveted afterward.

Another Saturday Afternoon Gone

When you're designing these things, just when you think you're safe to go back into the water, another shark pops its fin up.

Specifically the two quads will have to be joined with a spacer, a little like the filling in a sandwich, to ensure that the propellers and motors are basically contained within the vertical depth of the airframe... in other words so that they do not stand proud of the deck.

(You can see that better in the profile view of the 1:10 scale model below.)

Exactly how thick that spacer needs to be is as yet an unknown quantity, as the specs for the motor show only its own depth ~ six centimetres ~ and not that combined with the propeller.

This I shall do myself with a ruler, as computer-aided design is well above my pay-grade.

Incy-Not-So-Wincy Spider

On two minds about whether to order the body or the legs first, and opt for the latter. Back to Simmal in Preston who turn the order around in thirty minutes and I come away with a full set of 39" spars.

The section I've gone for is 2" by 1" by 1/16" so we're back into Imperial measures, what with 32" props too.

Reason I've gone for 39" is the fact the alloy retails in 5.0 metre lengths, and given the width of the blade used for cutting it, you can squeeze five of these out of each unit with no waste left over.... I'm that mean.

Happily it means that I've ten spars in all, with two left over to go toward repeat builds.

Bit nervous at the weight loading them into the Jimny, but then remember there's two to split from the pack.

And turns out they weigh less than 625 grams (1.33 pounds) apiece, which is almost half the weight of the altogether thicker spars I used for the original alloy build seen here.

It means I've doubled the number of rotor-arms without significantly increasing the weight, in the way that we've doubled the number of motors, propellers and ESCs to the same effect.

Gryphon incidentally are heavy-drone manufacturers in Korea and we simply share a common UK distributor who in turn imports the T-motors that power both efforts.

They lift cargo, however, whereas we intend to lift people.

Independence Day (2.0)

Been a year as of tomorrow since I formed the company with a view to this venture and I am surprised at how much ~ and equally how little ~ progress I've made.

With the electrical equipment out of the box now, here's an email to my team-mates and shareholders that is as good an update as any:

Gents,

Apologies for what appears to have been slow progress on all fronts but there are times you need to ‘step away from the vehicle’ and reflect on the way forward.

The motors and propellers and speed-controllers (ESCs) are landed from China, and to look at them is to realise that electric flight (and cars) really are the next big thing… the 32” carbon-fibre propellers are so light I figured the boxes were empty, and the motors at 4-inch diameter will raise around 20 kilos apiece (and we’ve eight).

Taking everything into consideration I figure the initial prototype has to take the form of a simple ‘flying carpet’ as per the attached, which is suited to a seat although a podium is not out the question.

With this up and running the fundamental design is adaptable to top- and mid-mounted positions around any form of vertical space-frame, but I like how this looks as a way forward.

Happily the eight-legged layout (basically two quads bolted together) also appears to have been wholly unique from the patent point of view beside promising more stability and redundancy.

The dimensions are well within the fly-off regs (which the ‘flying phone box’ variations generally weren’t) and the airframe is only around five feet square with props stowed as shown and therefore roof-rackable and flyable out the garage door.

We also have barn/workshop/flight-field facilities available to the project with a chance of on-the-spot accommodation… bit like the Wright Brothers at Kittyhawk, but without the sand.

The motors are driven by 48V so we’ve motor batteries available for ground-electrics and tethered tests, whilst the real-deal batteries will be sourced from a bespoke firm in Hong Kong.

A reason for the ‘powered-platform’ design is in fact that their weight (stored as ballast in the base) maybe as much as half my own weight for a flight of ten minutes in ground-effect.

The arrangement also favours the simplest possible flight-control architecture, with each propeller pair driving left-right-forward-back respectively and the throttle adjusting height alone.

Control laws for the engine-out case will have to wait and any failure prior will hopefully take the form of a tight-spiral descent to a softish landing with concomitant damage inevitable.

The lower set of propellers will also be shut down for take-off and landing with the upper set providing those manoeuvres, to avoid prop-strike.

(Ground-effect should assist this up to around one metre by providing a surplus of thrust of between 25% and 50%).

With an airframe complete in July we can then push for first-flight with or without tether and likely a seated mannequin, and having done this the type can be listed in global databases of such project builds.

The biggest players have spent billions of dollars to date on eVTOL types so we haven’t done too badly in the double-garage to date…

Contracts will also need signing this month as otherwise there’s no entry to the ‘pit-lane’ at the event itself in California.

C.

Under Construction

Parts have arrived and we're set to build the first iteration.