Gita – autonomous lightweight delivery system

So instead of tube, how about a delivery robot that's like an alley cat? One which grew up watching Indian Jones and superhero cartoons. And loves tightropes. And wants to be flying squirrel. And is wired into Google RealTime City Map...

I haz the cheezeburger. My human customer hungrily awaits. So I roll down the alley, and around the trash. Pause for traffic, and scoot across the street. Time for my usual northbound path. Up onto the roof. Down a toll zipline to another roof. Leap, wings out, glide, grab a street-pole cable, wings in. Roll along the cable, dodge pole, cable, pole, cable, etc. Roll down a quiet side street. Roof, alley, jump fence. Quick charge station. I consider Uber, but no! Here comes city bus #1726! Leap, electromagnet, hitchhike. Drop, wait for light, down sidewalk. Jump to porch, landing before the hungry human. A human lucky that it is I, city cat, that haz their cheezburger. And not some blind dumb hulking oft-clogged brute of a straw. Though if the straw ever gets built, I may ride that too. I take my bow, and my leave.

What constitutes travel infrastructure depends on what you can cope with. Wrt power, mechanics, sensors, information, and computes. It may be that those advance more rapidly than our ability to build large-scale physical-plant infrastructure. Like cars were easier than moving sidewalks. Robots that can use custom infrastructure where it exists, but can cope "on the ground" in the infrastructure gaps, would have higher complexity cost than say drones. But as costs change...

And hybrids may be interesting. The midday Amazon truck drives down the main road, shedding drones and robots, and taking on those dropped in the morning...

That's different from the military using drones, which are highly trained operators with robots in the air, which is a lot less cluttered.