Ever since Jeff Bezos pulled off a marketing coup by announcing his attention to launch an aerial delivery service using drones — in 2013, on the eve of Cyber Monday, no less — the notion of packages dropping from the sky within 30 minutes of placing an online order has remained a tantalizing fantasy for the public at large.
Nearly a decade later, Amazon Prime Air is rumored to be sputtering, but the concept of using drone delivery is alive and well, at least for some specific applications. Among the most vexing problems the industry has faced is how to safely put the package in the hands of the recipient — or at least on the ground next to them. At Expo, a company called A2Z Drone Delivery was showing off its solution.
“We sell a device that can be attached to any drone and turn it into a delivery drone,” explained Evan Hertafeld, A2Z’s co-founder. “It has the ability to carry a five-pound package and deliver it, at speed, from high altitude.”
When Hertafeld uses the phrase “at speed,” he isn’t kidding around — we’re talking free-fall in Earth gravity: 32 feet per second, squared. Naturally, I wanted to know whether or not this meant a hard landing for the cargo being delivered.
“We have a sensor suite that monitors the package during descent,” he said. “At precisely the right moment, we hit the brakes. We have a heat brake to decelerate the package and bring it to a stop 10 to 15 feet above the ground. At that point, the winch motor takes over and we have a controlled lower to the ground. At that point, it is automatically released from our hook and the only thing left behind is your box”
If the drone is hovering 100 feet above ground level, that whole process takes about six seconds, and 20 seconds later, the tether has been retracted and the drone is on its way back to base or to its next delivery location.
“That’s really important, because you want to minimize the time the aircraft spends on site, and you want to move away as quickly as possible from people and property,” Hertafeld explained. “So, we’re very consumer-friendly, as well as operator-friendly.”
To achieve the pinpoint timing required to pull off this aerial ballet, a LiDAR sensor on board the drone measures its precise altitude and the reel paying out the tether measures how much cord has been deployed. However, according to Hertafeld, that’s the easy part.
“So we’re monitoring the package as it falls, and we’re doing kinematic equations in real time,” he said. “We do some fancy-fancy mathematics, and we know the torque of our brake so we’re able to stop at just the right time.”
TEXT & PHOTOS BY PATRICK SHERMAN
