July 21, 2025, 8:26 am | Read time: 4 minutes
Vacuum robots are taking over floor cleaning in more and more households. These practical helpers tirelessly zip through homes, keeping rooms clean. But why don’t vacuum robots have corners? Wouldn’t that be much better for sucking up dirt from every nook and cranny? myHOMEBOOK reached out to manufacturers for this article to find out why vacuum robots are generally round.
There are inherent limitations in the development of a vacuum robot that a device must overcome. Width and height play a crucial role. When searching for lost dust particles, the vacuuming robot must fit between two chair legs and clean the floor under cabinets.
Since a home is rarely empty and furniture restricts the vacuum robot’s movement, special demands are placed on the navigation of such a device. In households with children, additional obstacles like scattered socks, toys, or other items further block its path.
D-Shape–A Good Corner Cleaner?
Vorwerk attempts to tackle the problem of dirty corners with D-shaped vacuum robots. “This design, combined with extra-wide brushes below and on the sides of the device, removes dirt and dust from all corners,” the PR manager of Vorwerk told myHOMEBOOK.
Vorwerk specifically chose the D-shape to clean corners and areas near walls as effectively as possible. Additionally, the vacuum robots from the Wuppertal-based company have flat edges to get as close as possible to hard-to-reach spots in the room. “Our devices create a wider cleaning area per vacuum pass due to the D-shape,” the PR department of Vorwerk emphasizes.
The D-shape is a compromise between round and angular. A completely angular vacuum robot would likely be even more efficient in corners and would almost hug walls while vacuuming. Why the angular shape is ultimately less favorable is illustrated in this short clip from the film “Austin Powers: The Spy Who Shagged Me.”
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Are Round Vacuum Robots Better?
An angular vacuum robot would be limited in its maneuverability. That’s why most manufacturers opt for a circular design. Newer models from Ecovacs have also adopted this approach after relying on D-shaped vacuum robots for a long time. A completely round vacuum robot can rotate on its axis without getting stuck on objects.
However, the question remains about corners and other floor areas that are not fully reachable due to the round shape. myHOMEBOOK also asked Roborock how they address the persistent corner problem. “For corner cleaning, our devices have extendable round brushes,” explains the Roborock spokesperson. “The devices move as far into the corner as possible. Then the cleaning continues without interruption.”
Is the D-Shape Too Complicated?
With the D-shape, the vacuum robot does drive directly into the corner. However, a reverse maneuver is necessary to get out. It’s likely a matter of preference as to what is ultimately “better.” Since battery life is always a concern, unnecessary maneuvers should be avoided.
Another small advantage of the round design: When the vacuum robot encounters smaller, movable objects, it has no consequences. “If a D-shaped vacuum robot turns and its wider angular side hits such items, they could fall over. A round vacuum robot simply rotates in place. There are no protruding parts,” reports the Roborock spokesperson.
At the end of the day, the customer decides. If the cleaning is sufficient for them, it doesn’t matter whether a D-shaped or round vacuum robot is responsible.