If we're going to follow the money and let the US patent content lead us by the nose, then it calls for a root-and-branch reappraisal of how we configure the eight motors that we've flight-tested recently in the double-decker format appearing two posts ago and which the patent examiner ruled out as at all original in the scheme of things. If there's one thing my brain's full of, it is the endless variations involved in configuring electrical motors around a space-frame for the purposes of flying people by drone.
At the smaller scale, the go-to drone for heavy-lift operations like professional video, aerial survey and crop-spraying is a ring-of-roses arrangement of eight propellers. This provides the most stable platform and the best aerodynamic efficiency, along with the most assured means of redundancy in the event of a failure of a single power unit. As a result, they don't come cheap, even at this 'industrial' scale.
At the same time they are almost invariably laid out is 'spider-leg' fashion, arrayed in a radial format around the centre-body. Up the ante to cargo drones or people-carriers however, and as often as not you've either a tic-tac-toe arrangement of four spars and a motor at the end of each. Alternatively you might find a pair of spars along the sides of a cockpit, with four motors arrayed along the length of each.
Neither suit the present objective of elevating human beings in a form of 'transporter' of the kind featured in episodes of Star Trek, emptying a 'phone-booth' of around two feet square (or one, in the case of the current half-scale prototype). Discounting the latter type altogether, the problem with a tic-tac-toe layout is that the central square is wholly defined by the diameter of the propellers, and far too big for our purposes.
Instead I opt for a 'Maltese Cross' layout, independent of the diameter of propellers on one hand and able to split into a pair of 'dog-bones' or bogeys for storage or transport. The planform in view will feature 60" long sections, 24" short (between motor axes) as well our 22" propellers. The pre-existing foot-square phone-booth will pass within the outline of its centre-section, the rig rising under its own power to engage the flange at the upper end of said booth and elevate its occupant.
I'm not a big one for setting people on top of drones in harms way ~ thought we could ~ for when all else fails in flight you're descending head first into the ground. Our first flight-test may yet simply affix the passenger booth to the underside (in which event the extent of any undercarriage is marked by the cross-hairs in the above draft), while my own preference is to start out the way we mean to finish by elevating into flight a wholly independent cabin.
It means at the same time that for the purpose of hauling cargo, we can containerise carriage in standardised boxes albeit with an overhang up top able to engage with the drone. I drive semis to pay the bills, and the patentable system changing the world in the 1960s was not the container itself, but those interlocks at each corner securing it.
Don't get me wrong... I'm a small foot-print kind of guy when it comes to personal air vehicles but consider this. We've eight under-powered motors we need to extract all we can from. I've two experts on tap who all along have been pushing me to adopt the tried-and-tested layouts commonplace to Pixhawk flight controllers, beside a patent agent's urgings to follow the money.
Above all this way forward most closely follows an original vision that was intended to entertain, at the same time as inspire.
Beam me up, Scotty.
