Stocktaking by drone

Automated stocktaking by drone is possible, but until now it had its weaknesses. The KION Group might have found the solution to these problems – and a truck has an important part to play.



Stocktaking tends to be pretty costly, in terms of both the time and the personnel involved. It is not uncommon for the manual counting process to interrupt the operation of the business, and it can increase the risk of accidents and damage to goods. Not to mention that no matter how diligent you are, it is very difficult to totally avoid errors. “As soon as humans are involved, there’s a danger that something will be missed,” says Tobias Zierhut, Head of Product Management – Warehouse Trucks at Linde Material Handling. According to experts, he adds, German companies spend up to 8 percent of the value of their stock on stocktaking.

If this process could be automated, would that not be more practical and efficient? This question gave the specialists in the KION Group an idea. “We asked ourselves if there were any synergies beyond robotics that we could offer our customers,” says Zierhut. One of the conclusions was: Why not automate stocktaking, for example using a drone?

Tobias Zierhut,
Head of Product Management Warehouse Trucks
at Linde Material Handling.

Tracking and battery life are no longer an issue

There are a number of stocktaking drones on the market, but they all have their weaknesses. Their battery charge might only last for 15 minutes, or half an hour at a stretch. And often they need to be manually controlled. The team at Linde robotics has responded to these challenges with a simple idea. The Flybox, a prototype jointly developed by Linde and Balyo, is directly connected to an automated Linde truck. “A standard truck,” Zierhut adds. “If the customer had to buy a new truck as well, it would be a considerably less attractive proposition.” Instead, the customer can use the Linde robotics truck in a variety of ways, for example to transport pallets in the daytime and to carry the drone at night. Battery life is no longer an issue, as the drone is attached to the truck via a robust and tear-proof Kevlar cable.

The connection to the Linde robotics truck also means the drone can be tracked around the warehouse, even without GPS, and is truly autonomous. Thanks to geonavigation in the truck, the system always knows exactly where the drone is. The truck transmits the coordinates on the ground, and a height sensor in the drone measures its altitude. “With pinpoint precision,” Zierhut says. The drone, which is the size of a small briefcase, takes to the air using its six rotors. It then slowly makes its way up the front of a rack, taking a photo of every pallet storage space, and using its scanner to capture the barcodes of the stored goods. When it reaches the uppermost rack, it tells the truck to follow it to the next position. The application software allows users to view the photos and barcodes on their screens at any time and automatically transfer them to the inventory management program.

Strong interest in the prototype

In the not too distant future, drones could actually take over stocktaking – or certainly the tasks involving comparing photos, counting, and categorizing. They cannot look inside the packages and boxes yet, of course. But the Flybox is only a prototype, and is useful for gauging the level of interest in this innovation. “There has been strong interest,” says Zierhut, who has presented the drone at the LogiMat intralogistics trade fair and other events. “It was one of our highlights at the trade fair, and we had many inquiries.” The next steps will be to calculate the development costs in detail and to plan exactly how the final version might look. “The relationship between weight and flying capability is likely to be an important factor,” according to Zierhut. The heavier the drone, the more power it will need to fly.

It is his firm belief that the KION Group is leading the way in this technology thanks to the expertise of Linde robotics. “The autonomous trucks that our customers use already have the route and the map of the warehouse stored in their systems,” he explains. “This means the route programming required to carry out a stock check could be based on a standard task.” Market launch is likely to be in 2018 at the earliest.