Mary Cheh, who has sat on the Washington, D.C., City Council since 2007, took a brand new approach to filing legislation last month: Instead of walking it down to the legislative office herself, she had a robot deliver it.

It was a bit of a publicity stunt, of course, for the makers of the robot, a European company called Starship Technologies. But the manufacturers say it could upend the whole U.S. package delivery industry.

First, though, the robot -- which Cheh says looks “like a rolling cooler with a lot of electrical equipment built into it" -- will try to prove itself in Washington.

The legislation that the robot carried through the municipal offices gives the rolling delivery devices permission to operate on the sidewalks, making Washington the first U.S. city with the experimental technology. The robots are already roaming in the United Kingdom, Germany and Switzerland, delivering packages -- and sometimes hot food -- to customers’ doorsteps.

The idea, says Starship spokesman Henry Harris-Burland, is to use these delivery robots to reduce costs for retailers and make things more convenient for customers. The robots, which are designed to work within a mile or two of their base, are targeting what Starship sees as the most inefficient part of delivery services: the last mile. The stop-and-go routes of delivery drivers are slow, expensive and often inconvenient for customers.

These robots can replace bulky package trucks, says Harris-Burland. What's more, they're simple to use: Customers can choose when they want the package delivered and then track the robot's progress on their phone. When the package arrives, customers simply open the locked compartment with a special code.

“The power is in your hands," said Harris-Burland. "Unlike conventional delivery as it stands, you’re not given a two-hour window or a slip through your door or a parcel over your fence. You will call the robot when it is convenient to you."

Starship hasn't yet announced what types of goods it will deliver in Washington, but Harris-Burland said the company would announce that soon.

The delivery robots each have six wheels, weigh about 40 pounds and have nine cameras to help them navigate city neighborhoods. They are designed to travel mostly on sidewalks, although they can negotiate small curbs.

When they first hit the sidewalks of several residential neighborhoods in D.C. next month, the robots will be controlled remotely by humans. Over time, though, the machines will gather enough information to build 3D maps of the neighborhoods they operate in and work autonomously.

The new D.C. law explicitly grants Starship permission to test up to five vehicles on city sidewalks at speeds of up to 10 mph, although they typically travel 4 mph. Starship’s robots will join wheelchairs, bicycles and Segways as the only vehicles allowed to operate on sidewalks.

Starship considered many cities when it was contemplating where to make its U.S. debut. It ultimately chose Washington because of its good sidewalks and dense residential neighborhoods.

“On top of that, I suspect, and I hope it’s true that D.C. is pretty progressive and reformist and innovative and interested in new technology and putting it to work,” said Cheh.

Washington was one of the first places in the country to authorize ride-hailing apps like Uber, clear the way legally for autonomous vehicles, permit car-sharing services like ZipCar and car2go, and launch a bike-share system, Cheh noted.

If successful, the company hopes to bring the robots to other American cities, such as Austin, New York and San Francisco.