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Robots are literally taking up most of the task humans are capable of doing. And the most shocking thing is that they do it very well. Vacuum cleaners are not left out of this, and when we see them move, we can’t help but ask “how do robot vacuums find their base”? Their movement might seem hap hazard, but trust me, they are well guided.


Robotic vacuum cleaners find their base by making the most of the sensors they are built with to detect and navigate the area in which they are cleaning. The sensors they work with are bump sensors, optical encoders, cliff or height sensors, and wall sensors.

Integrating these sensors into a vacuum clear makes it very effective in cleaning. For instance, a bump sensor, as the name implies, makes the vacuum cleaner change direction when it hits objects like chair and table legs. The cliff sensor takes cognizance of the distance between its base and the floor. It makes this possible by sending the infrared light off and on the floor. If the distance between the floor and the vacuum base suddenly becomes higher, it probably has gotten to a stair, it adapts, and changes position.

For a wall sensor, the vacuum changes direction to the left or right when it hits a wall. The optical encoder of a robot vacuum cleaner is on a whole different level. It uses some light technology to know how many times the wheel of the vacuum turns. These sensors help to calculate the total distance covered by the vacuum cleaner.

These are the basic sensors that robot vacuum cleaners have to help them navigate and find their base. However, there are other sensors a manufacturer can add to the vacuum cleaner to make it differ one to another.


It might interest you to know that the navigations of robot vacuum cleaners were patterned after how worms and insects move. This was the grand work of a roboticist at Massachusetts Institute of Technology (MIT), known as Rodney Brooks. Some people refer to him as the father of robot vacuum cleaners. He realized that these little insects are not necessarily smart, but they just tend to follow some certain set of rules that is enough for them to survive by.

Therefore, a vacuum cleaner does not have to be necessarily smart to work. It just needs to adapt to the obstacles it faces, overcome them and clean up dirt. It does not even have to know the length and breadth of the area it is trying to clean. Simple things like turning away from a wall before hitting it are some of the “behaviors” roboticist have to program into a vacuum cleaner.


Let us now consider some of the behaviors a robot vacuum cleaner can have to help it navigate a room and find its base easily:

  • Ø When placed in a dirty area, the vacuum cleaner begins to move in spiral form making it clean the room by moving in expanding circles. This movement continues until it bounces of an obstacle or it has covered a large expanse of room size.
  • Ø If the vacuum cleaner bumps into an obstacle, it probably is a wall. It then changes direction to the left or to the right.
  • Ø If the vacuum cleaner moves seamlessly without hitting obstacles, it assumes a straight movement in any random angle it has been programmed to face.
  • Ø If it hits another bump while going straight, it circumvents the bump and then moves straight again.
  • Ø By virtue of careful calculations and programming, after turning at a random angle and going straight for a while, it begins to do a spiral again.

Following these behaviors help the vacuum cleaner know what to do if it gets stuck in its path. It can rotate, move backward or slowly, by way of creating a path for itself. If after all this is done and no way of escape for the vacuum cleaner, it beeps for help!


In spite of the vacuum cleaner being a robot, it can still need the assistance of humans to make it work better. Some of the things to do to assist the movement of a robot vacuum cleaner to its base are as follows:

Remove cords and long curtains

Sometimes, we leave USB cables and phone chargers lying carelessly on the floor. This could hamper the movement of vacuum cleaners. Long curtains that get to the floor are not left out of this too. If these items get stuck on the main brush of the vacuum cleaner, it could even make it stop dead in its track. To avoid this, make sure all objects including toys, socks, paper clips, wrists bands and any other object that could be lying loosely on the floor are removed. Make sure to raise and tie up curtains from the ground too.

Remove chairs

Just like they do in restaurants and bars, you could consider turning your chair upside down to create more room for the vacuum cleaner to clear off bread, biscuit and any other crumb from the floor without having the legs of the chair hampering its movement.

Keep charging area clear

Most robot vacuum cleaners are capable of returning to their charging base after cleaning. However, you have a responsibility to make sure that the area around the charging dock is clear enough for the vacuum cleaner locate it effortlessly. This will also make sure that the charging base is always connected. Preferably, you could place the charging dock some 2 feet away from any other object about 4 feet away from furniture. You can back it up against a wall, but make sure the ground is level too.

Clear tassels and shags

Robot vacuum cleaners have a record of ruining rugs that have their tassels laid out. Try to hide them under the rug so the vacuum cleaner can have smooth movement as opposed to having them stuck in the main brush. Also, try to move shags completely away from the path of vacuum cleaners. Instead of the cleaner to just remove dirt, it might end up pulling the shag.

Scheduled cleaning

With most of the modern robot vacuum cleaners available, you have the ability to schedule days and time for cleaning. You can program the vacuum clean when you are not around. Maybe you’ve left for school, work, or some other place, you return and find the floor clean. All of these can happen without you and the vacuum cleaner getting in the way of each other.

Build artificial walls

It is very possible to restrict the robot vacuum cleaner from covering some ground space, for reasons best known to you. You can program some more recent vacuum cleaners with your mobile App to make them acknowledge barriers with their advanced laser navigation sensors.

In fact, some models come with boundary strips that makes the vacuum cleaner believe it’s a virtual wall, hence redirecting it to some other location in the house. However, if the one you have does not have these features, you can use a physical barrier to achieve this.

Clean your vacuum cleaner

Make a habit of cleaning your robot vacuum cleaner periodically. Make sure you wipe off dust, cut off hair and empty the trash to make the vacuum cleaner perform better. It is important that you also clean off dust from the sensors and charging base. Twice or thrice a year, we recommend that you change the filter of the vacuum cleaner entirely. If you can afford it, there are super robotic vacuum cleaners that can empty out their own trash. Cue in the Roomba s9 or the Roomba i7.


Robot vacuum cleaners are equipped with enough sensors to move seamlessly and find their base. However, I believe you now know you have your own part to play as well.