Designers of futuristic cityscapes envision delivery drones dropping off your packages from the sky and driverless cars taking you to work. But the robotic delivery invasion already has arrived in the form of machines that look like beer coolers on wheels.
The ground-bound robots, developed by Starship Technologies, will be showing up any day in up to 10 US cities, ferrying groceries and other packages over what the company calls the "last mile," from a neighborhood delivery "hub" to your front door, all for as little as US$1 (HK$7.80) a trip.
A second company, TeleRetail, plans to test its sidewalk robots next year.
Like driverless cars, the delivery robots use cameras, GPS and radar to "see" their urban environment and navigate through it. The robots are the first of what the companies foresee as a wave of inexpensive, high-tech, electricity- driven alternatives to gasoline car- driven shopping trips and delivery trucks that contribute to traffic gridlock and pollution.
Urban futurists see the little robots as an integral part of a digitally based "smart city" landscape - although it will take time for humans to adjust to them, and they come with privacy concerns.
"We think there will be hundreds, if not thousands, of robots on the ground eventually around the world," said Allan Martinson, chief operating officer of Starship Technologies, started by the co-founders of Skype.
Torsten Scholl, founder of TeleRetail said: "Why have a vehicle as big as an autonomous car to deliver goods? We think of it as a self-driving trunk."
And tech gadget website Tech Crunch has called autonomous vehicles - like drones, driverless cars and delivery robots - among the "Top Five Technologies" that will define cities in the next decade.
Starship's delivery robots work this way: Customers use a smartphone mobile application to order their delivery. A text alerts customers - "You have a robot waiting for you outside" - when the robot is near their home or business. A person must be present to receive the delivery because only the customer has a unique code to unlock the robot's box.
Cities that have laid out the welcome mat for the robots see practical promise in them.
"We're excited," said Catherine Ralston, economic development manager of Redwood City.
"They did a video in our downtown of the robot going into the bakery, picking up baked goods, and at the moment it rolled into City Hall, it popped open and presented the cookies to city council."
They're thinking of using the robots for city services, such as delivering library books.
The Washington, DC, council passed legislation last month that allows up to five different robot companies to operate in the area.
"To be candid, I'm not at all futuristic. I'm a here-and-now kind of person," said Leif Dormsjo, head of the district's Department of Transportation. "But our approach to transportation innovation is that we want to be a catalyst for new and interesting technologies. We have a permissive attitude about cooperating with new technologies."
Whether city dwellers will be as enthusiastic as their city leaders are is open to question.
A year ago, a robot called HitchBOT traveled across Canada, the United Kingdom and Holland before it was brought to the United States. The robot was a social experiment started by two Canadian professors. It looked like a cartoon human and was designed to be picked up on the side of the road voluntarily by drivers, like a hitchhiker.
It posted photos of its adventures to its popular Twitter, Facebook and Instagram profiles, and its trek appeared to be well-received. But after just two weeks in the United States, the HitchBOT's world trip ended when it was found dismembered in Philadelphia.
"Humans don't always act in rational ways," said professor Missy Cummings, director of the Humans and Autonomy Lab at Duke University.
"Look, I'm from the Deep South, and as soon as a robot delivers a six- pack of beer down there, they'll get out the guns and shoot it up."
Starship Technologies already has robots operating in 58 cities in 16 countries around the world. More than 1.7 million people have encountered the robots on sidewalks, or used their services - without incident. "We took a video in London showing that 3,000 people passed by our robots without even noticing them," said Martinson.
Ralston said test robots haven't caused any issues so far. "People enjoy seeing the little robots. Or they completely ignore them, they don't even take a glance. They realize, okay, there's something rolling along the sidewalk. It looks all right."
But Cummings worries that new technologies are being developed without enough attention paid to how they will interact with people, or how people will react. "It's a huge problem in robotics, which are developed by engineers" who know little about human interaction, she said. "Look at Google Glass.It wasn't weird to geeky engineers." But real people didn't want to use or wear the glasses - or have their photos taken by people wearing them.
The presence of video cameras in the robots is a potential privacy issue, too, said Jeramie Scott, director of the Domestic Surveillance Project of the Electronic Privacy Information Center.
"You can imagine these autonomous drones, on the ground or in the skies flying around, with a lot of surveillance equipment," he said.
Starship Technologies uses high- definition video cameras as part of its location triangulation, which allows the robots to navigate sidewalks and curbs, to track the robots.
But spokesman David Catania said the company generally does not keep high-resolution images, except if there is a safety or security issue like vandalism. When the devices are being operated by humans, a lower resolution feed is used and images are blurred.
For tech-friendly cities like Austin, Texas, city planners say: "Bring it on."
"We're always open to new ideas," said Jason Stanford, communications director for the mayor's office.
"We've got [driverless] Google cars operating all over the place here, and we don't get a single complaint about them," he said. "Now, we do have complaints about wild peacocks, but that's animals."