Where is the obstacle sensor in the robot vacuum cleaner Xiaomi: location, types and health check

Xiaomi’s robot vacuum cleaners are smart assistants that save you time cleaning, but their effectiveness depends on the health of sensors, especially obstacle sensors. If your Mi Robot Vacuum, Viomi or Dreame starts to beat furniture, ignore walls or get stuck in corners, these components are likely the problem. In this article, we’ll look at where the obstacle sensors in popular models are physically located, how they work and what to do if they fail.

It is important to understand that different lines of Xiaomi robot vacuum cleaners use different types of sensors: infrared (IR), Ultrasonic, laser (LiDAR) and even cameras, which are located and numbered depending on the model and generation of the device, for example, low-end versions like the Mi Robot Vacuum-Mop 2 Lite are equipped with only basic IR sensors, whereas flagships like the Xiaomi Robot Vacuum-Mop 2 Pro or DreameBot. X30 Ultra have sophisticated navigation systems with laser scanners and tof cameras.

Before you take the vacuum cleaner apart or bring it to the service, check that it may be solved by simply cleaning the sensors or resetting the settings, and we will explain in detail how to diagnose a malfunction and what to do in each case.

Types of obstacle sensors in Xiaomi robot vacuum cleaners

Xiaomi’s modern robot vacuum cleaners use a combination of several types of sensors to detect obstacles, each of which is responsible for its own workload:

• 🔴 Infrared (IR) They're the simplest, cheapest sensors, and they're mounted on a bumper, and they detect obstacles 5 to 10 cm away, and they're a reflection of the signal, and if the beam comes back, the robot knows there's a barrier ahead.
• 🔵 Ultrasonic sensors are more accurate than IR and are used in mid- and premium segment models (for example, Viomi). V3). They can “see” obstacles at a distance of 1-2 meters, but are sensitive to soft surfaces (for example, curtains).
• 🟢 Laser sensors (LiDAR) – installed in top models (Xiaomi Mi Robot Vacuum-Mop 2 Pro, DreameBot) L10s Ultra. They're making it. 3D-a map of the room with millimeter accuracy, usually located on the top cover in the form of a rotating "turret".
• 📷 Cameras (ToF or RGB) — It is also available in the latest models (e.g. DreameBot). X30 Ultra: Analyzes real-time images, detects types of obstacles (furniture, wires, pets).
• 🛡️ Collision sensors (bumper) are mechanical or piezoelectric sensors that are triggered by physical contact with an obstacle.

Most models use a combination of 2-3 sensor types, such as the Mi Robot Vacuum-Mop P with bumper IR sensors and ultrasonic sensors on the front, and the DreameBot on the front. Z10 The Pro also has LiDAR for mapping, and the more expensive the model, the more complex the navigation system is.

Where exactly are the sensors of obstacles: diagrams and photos

The location of the sensors depends on the model, but there are general principles, and below we will analyze the most popular line of Xiaomi robot vacuum cleaners and show where to look for sensors.

Budget models (Mi Robot Vacuum-Mop 2 Lite, Redmi) 1C)

In low-cost vacuum cleaners, only infrared sensors and a mechanical bumper are used.

• 📍 Front bumper – 2-4 IR sensors (small black or transparent windows).
• 📍 Side sides – 1-2 IR sensors for wall detection.
• 📍 The bottom part is the drop sensors (not to be confused with the obstacle sensors!).

For example, in the Mi Robot Vacuum-Mop 2 Lite, the IR sensors are symmetrically positioned on the front bumper and sides, easily identified by small circular holes 3-5 mm in diameter. If these holes are contaminated, the robot will begin to "not see" the obstacles.

Mid-segment (Viomi) V3, Mi Robot Vacuum-Mop P)

And here you add ultrasonic sensors that are on top of the body.

• 📍 Top panel – 2 ultrasonic sensors (small round or oval holes).
• 📍 Front bumper – 4-6 IR sensors.
• 📍 Side sides – 1-2 IR sensors for wall circumvention.

In Viomi. V3 So ultrasonic sensors are hidden under a plastic grid on the robot's forehead, and they're easy to miss, because they don't look like classic sensors. If the robot starts to beat against glass surfaces (tables, cabinets), they're probably the problem.

3. Premium models (DreameBot) X30 Ultra, Mi Robot Vacuum-Mop 2 Pro)

Flagship vacuum cleaners are equipped with LiDAR and cameras.

• 📍 Rotating "turret" on the lid - laser sensor (LiDAR).
• 📍 Front panel – ToF camera (in DreameBot) X30 Ultra, it's hidden under black glass).
• 📍 Bumper - IR sensors (reserve system).
• 📍 Side Sides – ultrasonic sensors for precise obstacle avoidance.

In DreameBot. X30 The Ultra camera is located to the right of the LiDAR turret, which analyzes the image and recognizes objects (for example, distinguishes a chair from a pet). If the robot starts to ignore small obstacles (socks, wires), it may be contaminated or malfunctioning.

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If your robot vacuum cleaner starts to beat transparent obstacles (glass, mirrors), the problem is most likely in ultrasonic sensors or a camera.

How to check the performance of obstacle sensors

If the Xiaomi robot vacuum cleaner is acting strange (cannot see the wall, gets stuck, bangs on furniture), the first thing you need to do is check the sensors.

1. Visual inspection - make sure that the sensors are free of dirt, dust or scratches. Wipe them with a soft napkin soaked in alcohol.
2. Hand test – place your hand to each sensor at a distance of 5-10 cm. the robot must stop or change its trajectory.
3. Check through the app – in Mi Home or Dreame, open the Device Status (or Sensors) section, which displays the status of the sensors.
4. Error Diagnosis – If the robot produces an error such as Error 9 or Error 12, it may indicate a malfunction of the LiDAR or camera.

For a deeper diagnosis, you can use a service menu. For example, in DreameBot, press the Spot Cleaning and Home buttons for 5 seconds - the robot will turn on self-testing mode and show the status of all sensors on the display.

Examine sensors for dirt|Drain the IR sensors with alcohol|Check the reaction to the obstacle (to hold your hand)|Run the diagnosis through the application|View the error logs in Mi Home-->

If the robot ignores the obstacles on one side only, the problem is localized, for example, if it only hits the right leg of the table, the right IR sensor or the ultrasound sensor is likely to not work, in which case you can temporarily tape the faulty sensor (so that the robot does not rely on it) and check whether the navigation improves.

Cleaning and maintenance of sensors: step-by-step instructions

Contaminated sensors are the most common cause of navigation failures: dust, animal hair and greasy spots (such as from kitchen splashes) interfere with the proper operation of the sensors. Cleaning should be done at least 1 time per month, and if there are animals in the house - every 2 weeks.

You'll need:

• 🧴 Soft lilac wipe (microfibra).
• 💧 Isopropyl alcohol (70% or higher) or a special liquid for optics cleaning.
• 🪛 Plastic blade (for careful removal of covers).
• 🔦 Lantern (to better consider pollution).

Step-by-step cleaning:

1. Turn off the robot vacuum cleaner and remove the battery (if possible).
2. Wipe all sensor holes with a dry wipe to remove dust.
3. Soak the napkin in alcohol and wipe the sensors gently. Don't use cotton swabs - they can leave the fibers behind!
4. For LiDAR sensors (in models with a "turret") remove the protective glass (if it is removable) and wipe the lens from the inside.
5. Blow the sensor holes with compressed air (for example, a canister to clean the keyboard).
6. Let the robot dry for 10-15 minutes before turning on.

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Never use abrasive materials (sandpaper, hard brushes) or aggressive liquids (acetone, gasoline) to clean sensors, which will damage optics and lead to irreversible breakage!

After cleaning, test the robot in a test mode, run a small room cleaning and watch it bypass obstacles, and if the problem persists, the sensor may be faulty and needs to be replaced.

⚠️ Note: In models with ToF cameras (e.g. DreameBot) X30 Ultra) you can't touch the lens with your fingers - greasy marks distort the image. Use only special wipes for optics.

Typical sensor faults and repair methods

If cleaning didn't work, the sensor probably didn't work, and let's look at the most common breakdowns and their solutions.

The most common failure is the failure of IR sensors, which eventually become blind due to contamination or mechanical damage, and you can replace them yourself if you find original parts (for example, on AliExpress for "Xiaomi vacuum"). IR sensor”). The cost of one sensor is from 200 to 500 rubles.

And the more complicated thing is LiDAR, where if the laser sensor fails, the robot stops mapping the room and moves randomly, and there are two options:

1. Replace the LiDAR module (price - 1500-3,000 rubles).
2. Disable mapping in settings and use the robot in random cleaning mode (less efficient).

In models with cameras (for example, DreameBot) X30 Ultra can be a distraction in focus, and this is manifested by the robot not seeing small obstacles (socks, toys), the solution is calibrating the camera through a service menu or replacing the module.

⚠️ Warning: If the robot is still not working properly after the sensor is replaced, check the firmware. Sometimes navigation failures are caused by software errors. Update the software via the Mi Home or Dreame app.

How to turn off obstacle sensors (if they interfere)

Sometimes the obstacle sensors become too sensitive, such as a robot stopping for every small piece of debris or refusing to go under low furniture, in which case you can temporarily turn off some of the sensors or reduce their sensitivity.

Methods of shutdown:

• 📱 Through the application – in Mi Home or Dreame, find the section “Cleaning Settings" → "Sensitivity of sensors. Here you can reduce the response to obstacles.
• 🔧 Physical shutdown – seal unnecessary IR sensors with opaque tape (for example, if the robot is afraid to go under the sofa).
• 💻 Firmware – in some models, you can turn off individual sensors through an engineering menu (root access is required).

For example, in Viomi V3 You can turn off the ultrasonic sensors through the developer menu:

1. Press the Spot and Home buttons for 10 seconds.
2. In the menu that appears, select Sensor Settings.
3. Turn off Ultrasonic or IR (willingly).

Note that turning off the sensors impairs navigation, and the robot can start to hit furniture or fall down stairs, and only use this method as a last resort!

Where to buy spare parts to replace sensors

If the obstacle sensor fails, you can replace it yourself, and the main thing is to find an original or compatible part.

• 🛒 AliExpress is the biggest choice. Look for a robot model (e.g., "Viomi") V3 IR sensor or "DreameBot" X30 Ultra LiDAR”): Prices are lower than in Russia, but delivery takes 2-4 weeks.
• 🏬 Robot vacuum cleaner parts stores, such as RoboShop, Xiaomi Store or DNS. You can find original details here, but the price will be higher.
• 🔧 Service centers -- some workshops sell used parts from disassembled vacuum cleaners. It's cheaper, but the risk of running into a faulty module is higher.
• 🌍 eBay, Amazon -- suitable for rare models. Delivery takes longer, but sometimes you can find unique parts.

When buying, pay attention to:

• 🔍 Compatibility – the sensor should be suitable for your model.
• 📦 Set – some vendors sell only the sensor without mounts.
• ⭐ Check if other buyers are complaining about marriage.

Average Parts Prices (2026):

• IR sensor: 200-500 ₽.
• Ultrasonic sensor - 600-1200 ₽.
• LiDAR module - 1500-3000 ₽.
• ToF camera - 2000-4000 ₽.

If you're not sure about your abilities, you should go to the service. It'll cost you 1,000 to 2,500 to replace the sensor in the workshop. ₽ (plus the cost of the spare part).

FAQ: Frequent questions about obstacle sensors in Xiaomi robot vacuum cleaners