11 Different Sensors On a Roomba And Their Uses

Last updated on January 5th, 2024

A Roomba operates based on an impressive array of sensors. These sensors let your vacuum navigate complex house settings, avoid obstacles, and deliver efficient cleaning results. Without them, your vacuum basically won’t function. Let’s take a look at what different types of sensors iRobot has imbibed in its Roombas.

How many different sensors are there on a Roomba?

There are a total of 11 different sensors on a Roomba:

  1. Bump sensor
  2. Cliff sensor
  3. Wall sensor
  4. Dirt sensor
  5. Floor tracking sensor
  6. Camera sensor
  7. Object sensor
  8. Optical sensor
  9. Room confinement sensor (RCON)
  10. Full bin sensor
  11. Fluid level sensor

Different sensors on a Roomba

Let’s discuss these sensors in a bit more detail.

Types of sensors on Roomba
Different sensors on a Roomba

Bump sensor

A bump sensor, also known as a light touch sensor, is present on the front of the vacuum. If your vacuum bumps into any object, this sensor will recognize the touch and turn away. This prevents your vacuum from trying to go over objects like chair legs or cupboards.

For all round-shaped Roombas, the bump sensor is present on the front arc of the circular shape, while in D-shaped ones, it is present on the front of the flat surface of the D.

Bump sensor placed on the front arc of the vacuum
Bump sensor placed on the front arc of the vacuum

Is a bump switch a digital sensor?

Yes, a bump switch is a digital sensor as it has to determine whether something has bumped into it or not. Thus, only the two possible values, 0 and 1, are acceptable as outcomes.

Cliff sensor

 Cliff Sensors used in Roomba
Cliff Sensors

A cliff sensor prevents your Roomba from falling down the stairs. These sensors are located all around the base of the vacuum. There are 4 to 6 of them, depending on the make of the model. They measure the distance between the floor and the base of the vacuum. If they encounter a sudden increase in this distance, they back off.

These sensors tell the robot where it is not supposed to go based on the difference in the height of the floor. These sensors are also responsible for your vacuum going or not going over door frames, railings, and thresholds.

For curious minds: The cliff sensors use IR radiation to measure the distance between the floor and the vacuum base. The IR light is bounced off the floor, and the amount of time it takes to return is counted. This then determines the distance.

Wall sensor

As the name suggests, a wall sensor senses the presence of walls. These sensors use a similar mechanism as the cliff sensors to detect walls. It is because of these sensors that your vacuum doesn’t bump into walls and turn around when it detects one.

Wall sensors also recognize other surfaces, like cupboards, sofas, doors, etc., as walls if there’s no gap between the floor and the object’s surface.

Does Roomba hit walls?

If the wall sensors are dysfunctioning, then a Roomba can hit walls. The solution is to clean wall sensors with a soft cloth. If the problem persists, then contact customer care.

Dirt sensor

A dirt sensor senses the presence of dirt and also determines its quantity. If the amount of dirt is more in a particular region, it kicks in the dirt detection technology. This tech then asks the robot to go over the heavy traffic region multiple times to ensure all of the dirt is picked up.

It is a piezoelectric sensor, which is a small crystal that recognizes when dirt comes in contact with it. On contact, it generates small electrical impulses. If excessive electrical impulses are generated, the dirt detection feature gets triggered. And then, the vacuum cleans the spot where these impulses were generated more.

Where is the Roomba dust sensor?

The dust (dirt) sensor in Roomba is located on the base of the vacuum.

Floor tracking sensor

Floor Tracking sensor
Floor Tracking sensor

A floor tracking sensor is an optical sensor that will track the surface your vacuum is running on. This sensor is responsible for tracking the location of your vacuum. It works very similarly to your computer’s mouse. It precisely tracks the movement of your Roomba and sends the data to the cloud for further use.

The floor tracking sensor is located on the base of the vacuum. It constantly comes in contact with dust, so you have to clean it timely. If you are having a problem viewing the location of your robovac, then ensure that this sensor is free from any dust.

Does Roomba work on different floor types?

Yes, Roomba can work on different floor types like hardwood and carpets. The floor tracking sensor will note the change when switching from one surface type to another.


A camera views the robot’s surroundings and helps it to determine the best path forward. It is located in different locations for different models of Roombas. You will find a front-facing camera on the j series models. For the s series models, you will find it behind the golden disc on the top. On most other models, the camera is situated somewhere on the top of the vacuum.

Why do Roombas have cameras?

The camera plays a vital role in object recognition and hazard detection. In the latest models, like the j7, the camera plays an integral part in navigation and obstacle detection.

Object sensor

An object sensor recognizes any objects that come in the cleaning path of your Roomba. These are mainly located at the front of the vacuum. It uses an IR transmitter and a photocell receiver for object detection.

Now this might sound very technical, but the work is pretty simple. The transmitter sends out a beam of IR light which reflects when it comes in contact with an object. This reflected beam is received by the receiver.

Optical sensor

An optical sensor measures how far your Roomba has traveled. These sensors are located on the robot’s wheels. They use a light sensor to count how many times the wheels have rotated. By comparing the rotation of the wheels and recording when the bot turns its wheels, this sensor determines the distance the vacuum has traveled.

You can view the area covered by the Roomba in your iRobot Home app. It is displayed as a part of the cleaning history, where the data is saved for future reference.

How to clean the optical sensor?

The optical sensor is imbibed well inside the Roomba’s body. It is not easy to reach as the opening is quite small. You can simply wipe the opening with a cloth, but there’s nothing more you can do to clean the optical sensor.

Room confinement sensor (RCON)

RCON Sensors in different series of Roomba
RCON Sensors in different series of Roomba

A room confinement sensor allows the Roomba to detect compatible devices like the virtual wall barriers, Home Base docking station, and Clean Base docking station. All Roombas except for the j series vacuums have an RCON sensor. The j series doesn’t need this sensor as it has a front-facing camera that can search and locate these devices.

If your vacuum is having trouble while docking or is not able to locate the docking station, then there could be an error with the room confinement sensor. Make sure you keep it clean, and free from dust. If the error persists, then contact iRobot customer care for help.

How do you test the room confinement sensor on a Roomba?

Manually place your Roomba away from the docking station and press the Home button on the robot. If your vacuum docks into the station without any issue, then your room confinement sensor is working just fine.

Full bin sensor

A full bin sensor senses that your Roomba’s dustbin is full. The indicator light on your vacuum will start blinking to indicate that the dustbin is full. You then have to empty your dustbin. If you have a self-emptying base, then you needn’t worry about that.

Where is the iRobot dustbin sensor?

There are two full bin sensors on the robot and four full bin sensor ports. Two of these ports are located inside the dustbin, and two are on the outside. Ensure that the sensors and sensor ports are always clean to avoid any errors.

Bin sensor used in Roomba
Bin sensor used in Roomba

Fluid level sensor

A fluid level sensor detects the amount of fluid in your Roomba water tank. It will create an alert when the volume of water in the tank is almost finished. This helps to refill the tank before all the water is used up, so the mopping action on your robot will not be hindered. This sensor is currently only available on the Roomba Combo j7+, as it is the only Roomba with a water tank.

Note: The error codes 1014 and 1015 are associated with fluid level sensors. Often restarting the Roomba makes the error go away. But if not, you will need professional help to get it sorted.

Check out: Roomba Error Code Guide


All these different sensors on a Roomba work together to give you the best cleaning experience possible. Each sensor plays its unique role in keeping the Roomba up and running.

If even one of these sensors is working, it can cause a hindrance to the cleaning process. That’s why it is important to do proper maintenance of these sensors. You can create a weekly cleaning schedule for all accessible sensors so that none get ignored.


Does Roomba have a LiDAR?

No, a Roomba does not have a LiDAR sensor for mapping.

What is the IR sensor used for in a Roomba?

The IR sensor is used for detecting movement and objects in the Roomba’s path.

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Siddhi Gurav

She is the editor and content writer at Smart Home Bulls. Siddhi merges her passion for language with SEO expertise. With 4 years of experience as a creative writer and a passion for smart home technology, she fits in perfectly at Smart Home Bulls. Her wide experience in content marketing has been an excellent addition to our team.

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