The delivery vehicle is suspended from three ropes allowing it to be positioned anywhere above the city and then lowering or picking up it's baggage.
The anchoring points themselves are situated in traingular locations held up high above the city by balloons. Each balloon is tethered to the ground with (at least) three ropes anchored in a triangular shape giving the anchor point good stability.
If needed the anchor points of the package are changed to a different set of "coordinating ropes" and then simply pulled into position inside the triangle, where it accepts or releases the package, rapidly for lightweight and non-fragile packages, but carefully and slowly for fragile cargo.
The anchoring points do not have to be permanent, and the anchors themselves can reach the new locations with a lightweight system similar to the one mentioned above, or, in case of leaving the inside of the grid, using an automated quadcopter.-- pashute, Dec 28 2020 Cargo for one of these https://en.wikipedia.org/wiki/SpidercamWorks for areas of large stadiums. [wjt, Dec 28 2020] Triangular location https://www.english...n-triangular-lodge/ [pocmloc, Dec 30 2020] I went to a triangular location once.-- pocmloc, Dec 28 2020 Lucky the crowd control police will be swapping helicopters for electric quadcopters.-- wjt, Dec 28 2020 Expensive, impractical, what's not to like? [+]-- Voice, Dec 30 2020 "Hangover delivery"?
Reminds me of the "chasm city" from a novel by the same name, in which spider-legged cars traverse fixed cables to move about the city.
I like this idea but would propose that the ropes be rapidly tightened to fling a package high into the air then softly catch it with a different set of ropes.-- sninctown, Dec 30 2020 //Expensive, impractical, //
Isn't all proto-stuff.-- wjt, Dec 30 2020 //only work in a triangular cities or regions//
Actually its more subtle than that. Suppose you managed to find three triangular sites, spaced far enough away from the edge of the city that the ropes between tham could deliver to anywhere in the city. Well, now there is a big selection pressure on new developments to happen within the space bounded by the ropes, and so the city will naturally grow to fill that triangular place.
On the other hand if the three triangular plots are at the edge of the city, then sites further round the edge which fall outside the range of this devide will lose value and utility and may even be abandoned and turn into first wasteland and second scrubland and third primeval forest, and so the city would over time shrink to become triangular.
There is another possibility, which is that smaller independent hangdelivery systems will be installed alongside the main one. A system which was one third of the linear size of the main system could be installed in the centre of each long side of the main system. The interface could consist of a series of intechange depots, so a parcel or person or other item could be dropped off by one system and picked up by the other. A Koch series of ever smaller systems could fill the entire area of the city. As long as the fractal edges were aligned with development plots, you would not need to have a series of tiny rope systems inside your bathroom cabinet to get the toothpaste from the tube to your brush.-- pocmloc, Dec 30 2020 //you would not need to have a series of tiny rope systems inside your bathroom cabinet//
Wait - you don't have one of those?-- pertinax, Dec 30 2020 I only said you wouldn't -need- to have one.-- pocmloc, Dec 30 2020 random, halfbakery