Watching a Roomba do its magic is satisfying if a bit baffling experience. You may have wondered how these adorable machines navigate their way around rooms.
Do they clean randomly or follow an intelligent pattern? How do they figure out which parts of the house need more attention, and which ones they should avoid?
The science behind the product
Autonomous robotic vacuum cleaners use a variety of technologies to navigate cleaning surfaces. That cute Roomba keeping your house squeaky clean is basically a robot and comes pre-programmed to perform certain maneuvers.
They do this by utilizing a variety of sensors. These allow them to visualize a room, avoid obstacles, and clean hard to reach parts. Newer versions such as the Roomba 980 and i7 also make use of increasingly sophisticated mapping technology.
The types of sensors found in robotic vacuum cleaners include:
They’re located on the Roomba’s shock-absorbing bumpers, which allow it to clean while avoiding obstructions. When it encounters an obstacle, it reverses to a point where it can continue moving in a straight line without hitting it again.
In this case, its navigation is determined by the side on which its obstacle sensors are activated. For instance, if the right obstacle sensors are triggered, it will move to the left.
These are standard safety features in all robot vacuums, meant to protect them from damaging falls. They constantly emit infrared signals as a way of measuring the distance to walls and other obstacles.
If these signals don’t bounce back immediately, the Roomba concludes there’s a stair or other form of a cliff and changes direction.
They help robotic vacuum cleaners differentiate between walls and other obstacles like furniture. Once a wall is detected, the Roomba will clean along with it without bumping against it.
These sensors also allow it to identify doorways and other open spaces between walls. By doing so, it can navigate towards other rooms in the house.
By using light sensors, the Roomba calculates the number of wheel rotations used while cleaning. Multiplying this by the wheel circumference gives it an accurate calculation of distance traveled.
In the past, this was how all robotic vacuum cleaners moved, which led to haphazard navigation. It’s now used in cheaper models, which take longer to clean surfaces.
Vision and mapping
The Roomba 980 added a camera and image analysis software to its navigation capabilities. The camera captures various images of the room it’s cleaning.
The software then processes them and systematically creates a reliable map for future reference.
Other than cleaning your hardwood floors more efficiently, this technology allows you to see a map of where the robot has vacuumed.
The Roomba 980 and flagship i7 also have the innovative VSLAM (Vision Simultaneous Localization and Mapping) technology. This allows them to come up with and customize the most effective cleaning pattern for your house.
It also means the Roomba won’t need to survey the room every time it cleans. The i7’s iAdapt 3.0 software can save up to 10 maps to a cloud server through its persistent mapping technology.
This means it cleans rooms it’s already familiar with. By using these saved maps, it can navigate the room in a smarter, more efficient pattern.
Future cleaning runs are also likely to be shorter and more thorough because the map is constantly being updated.
These robots can still find their way around a room even if some parts of their navigation systems are blocked.
For instance, if your cat blocks the camera by riding on the Roomba, it can still use its various sensors to clean accurately. This is referred to as sensor fusion.
Other navigation techniques
Other robotic vacuum cleaners such as Neato Botvacs use LIDAR(Light Detection and Ranging) technology for navigation.
Lidar is becoming an increasingly popular navigation solution for various innovative products. These include unmanned aerial vehicles, self-driving cars, and 3D mapping tools.
Lidar measures distance by a pulsed emitting laser. This allows vacuum cleaners to identify obstacles, scan, and navigate rooms more efficiently while cleaning.
Most Roombas use a combination of navigation techniques to come up with the most efficient cleaning patterns. As robotics, AI, IoT, and associated technologies get better, and smarter solutions are guaranteed to hit the market.
At the moment, iRobot leads the pack with their advanced navigation features. We can’t wait to see what new features future models will have, or how competitors will respond.