Corvus Robotics autonomous drones take warehouse inventory faster than humans
Warehouses offer a range of opportunities for robots. A semi-structured controlled environment, many repetitive tasks, and people who would prefer to be somewhere else. Robots excel at work involving moving things from one place to another, but there are many other tasks that could make warehouses run more efficiently.
Startup Corvus Robotics has just emerged from stealth and said it wants to tackle inventory tracking, making sure a warehouse knows exactly what is where. This is a harder task than it seems, and not every robot can handle it. The company has developed autonomous drones that can fly unattended for several weeks, collecting inventory data without human intervention.
Many warehouses have a special team of people whose job is to walk through the warehouse and scan materials to keep an up-to-date list of where everything is. This task is very important but also very boring. It turns out autonomous drones can scan 10 times faster than people.
Corvus Robotics drones can inventory an entire warehouse on an ongoing basis in just a couple of days, while a human crew would need weeks to do the same.
Inventory is an important opportunity for robotics. There have been many attempts at inventory in places like supermarkets, but warehouses can be different. Robots that can handle this task in a supermarket simply will not manage it in huge warehouses, because they cannot see inventory stored on shelves up to the ceiling (ceilings can be more than 20 m high). That is why the innovative drone form factor offers a unique and useful solution.
A warehouse is probably fairly considered a semi-structured environment. At the start of deployment, Corvus will generate a single map of the work area that includes geometric and semantic information. Then the drones will autonomously update this map with every flight throughout their operating time.
Walls, ceilings and large racks do not move, but this does not help the localization system, since they all look alike. Truly unique things (items on shelves) constantly change. Corvus's chief technology officer believes this is a huge problem, but a solvable one.
The drone has a docking station for charging and an initial map, but otherwise it performs built-in visual-inertial SLAM (simultaneous localization and mapping), volumetric mapping and motion planning with 10 cameras and an autonomy stack running on ROS and PX4 for real-time flight control.
"For us, full autonomy means continuous operation without human involvement in a specific scenario or environment. Clearly, this is not level five autonomy, because no one is working on level five, which requires general intelligence to fly anywhere. But at level four, for the interior of a warehouse, drones fly on a schedule, intelligently find items of interest while avoiding collisions, return to the ground, recharge and share this data," said Jacky Wu, CEO of Corvus Robotics.
Corvus is not yet ready to reveal all its cards, but has said it uses some of the structured components of the environment in its SLAM solution. One important element of this is the ability to localize in very large, unstructured environments where things constantly change, without relying on external infrastructure. In essence, all the computing capabilities of a self-driving car have been compressed to the size of a drone.
Corvus can scan 200 to 400 positions per hour, including drone recharging time. At ground level this is roughly equal to human speed, but when inventory scanning starts above ground, the drone maintains a constant scanning rate, while for a person it becomes exponentially harder. Most items in a tall warehouse are not at ground level, since it covers only one or two levels of space, which can reach 20 m.
With some exceptions, it is unlikely that most warehouses will be free of people in the foreseeable future.
“We can work when no one is nearby, so our customers often schedule drone launches for the third shift, when the warehouse is dark. There are also customers who want us to work alongside people, which initially scared us, since interaction with people can be quite complex. But over the past few years we have built safety systems to handle this”
In addition to collision avoidance, provided by a 360-degree vision system (which the drone uses for navigation), it has many safety-oriented behaviors, including searching for clear flat areas to land in an emergency.
However, the main way Corvus tries to maintain safety is by keeping drones and people as far apart as possible, which may require changing warehouse processes. Corvus Robotics' CEO says: "If you see a drone in an aisle, just don't enter until it finishes its work."
