Xiaomi Mi Robot Vacuum is a smart device that makes cleaning a home much easier. However, over time, its sensors become contaminated, leading to navigation errors, incorrect mapping of the room or even a complete shutdown. Cleaning sensors is not just a recommendation, but a necessary procedure to maintain the accuracy and efficiency of the device.
In this article, we'll look at what sensors Xiaomi's robot vacuum cleaner has, how to clean them properly, and what happens if you neglect care, and why vacuum cleaners start to get lost in space, bump into furniture, or ignore obstacles, and how to fix them. And we'll also explore a little-known nuance: why, after cleaning the laser sensor, the robot can temporarily go blind, and how to avoid it.
What sensors are in Xiaomi Mi Robot Vacuum and what they are responsible for
Xiaomi's robot vacuum cleaner has several types of sensors, each of which performs a different function, and their contamination causes problems ranging from inaccurate mapping to complete shutdown of the device.
- 🔦 laser sensor (LDS) — It's responsible for scanning the room and building the map, and pollution causes the robot to go blind and move around in a chaotic way.
- 🚪 Bumper sensors detect obstacles when they crash, and if they're contaminated, the vacuum cleaner may not respond to impacts or may stop for no reason.
- 👁️ Optical sensors (cliff sensors) prevent falling from stairs and high rapids, and the dust on them makes the robot "fearless" - it can slide down.
- 🌀 The gyroscope and the accelerometer are responsible for orientation in space, and their failures lead to the vacuum cleaner driving in a circle.
- 🔋 Charge sensor - monitors battery levels. Contact contamination can cause charging problems.
The Mi Robot Vacuum-Mop 2 Pro and later also have ultrasonic sensors for improved obstacle detection, and cleaning them requires a special approach, as they are sensitive to moisture.
If you notice that the vacuum cleaner is getting worse at orienting itself, often hanging out or ignoring obstacles, the first reason is usually contaminated sensors, but before cleaning, it's important to understand which sensor is failing so you don't waste time.
Signs Xiaomi robot vacuum cleaner sensors are contaminated
How do you know when it's time to clean up? There are a few obvious symptoms that indicate sensory problems:
- 🗺️ Robot builds an inaccurate map of the room or refuses to keep it.
- 🤖 The vacuum cleaner takin' with furniture, although he used to bypass it.
- 🌀 "Drunk driving in circles or chaotic movements for no apparent reason.
- ⚡ Not returning to base for charging, although battery is discharged.
- 🚫 Ignores virtual walls or cleaning areas configured in the app.
- 📉 Falling down stairs, though I've found them before.
If one of these signs is present, one or more sensors are contaminated (LDS) Most of the time, it's dusty, because it's constantly rotating and it's attracting particles, and optical sensors (cliff sensors) can get covered in a film of fat if the vacuum cleaner is running in the kitchen.
It's important not to confuse sensor contamination with software failures, and if there's a problem after cleaning, you might need to reset your settings or update your firmware, but 80 percent of the time, it's the dust that's to blame.
⚠️ Note: If Xiaomi’s robot vacuum cleaner starts to behave even stranger after cleaning the sensors (for example, spinning around or not responding to commands), check if you damaged the sensors. The laser sensor is especially sensitive to mechanical stress - it can not be rubbed with hard objects!
Preparation for cleaning: what you need and precautions
Before you start cleaning the sensors, prepare the necessary tools and materials.
- 🧴 Soft brush (for example, for drawing or cleaning lenses).
- 🧻 Microfibre wipe (without pile!).
- 💨 A container with compressed air (for blowing dust from hard-to-reach places).
- 🪛 Plastic blade or mediator (for careful lid fitting).
- 🧴 Alcohol wipes (for degreasing optical sensors).
- ⚡ Screwdriver (if you need to disassemble the body).
What can't be done:
- 🚫 Use water or liquid cleaning products – they can damage electronic components.
- 🚫 Use abrasive materials (sandpaper, hard brushes).
- 🚫 Blow on sensors with the mouth – saliva contains fats that will leave the film.
- 🚫 Disassemble the robot without disconnecting it from power.
If you're cleaning the sensors for the first time, take a picture of each step of disassembly - this will help you put the device back together correctly. Also make sure the robot is completely off (not just in sleep mode!). 3-5 seconds until the indicator goes out.
Turn off the robot vacuum cleaner
Prepare tools (tassel, napkins, compressed air)
Take a picture of the process of disassembly (if required)
Make sure the battery is not fully discharged (minimum 20%)
Working on a clean, flat surface-->
Step-by-step: how to clean the laser sensor (LDS)
laser sensor (LDS — Laser Distance Sensor is the eyes of a robot vacuum cleaner. It rotates at speed. 5-10 And then you get dust, spiders, even tiny hairs, over time, scanning the room, and you get a distortion of the map, or you lose your orientation.
How to clean LDS:
- Turn off the robot and turn it upside down (where the laser module is located).
- Blow the dust carefully with a compressed air can. Keep the balloon upright to avoid liquid.
- If there is any contamination, use a soft brush to sweep dust from the rotating glass.
- For persistent stains, wipe the glass with a dry microfiber wipe. Don't press hard!
- Check if there is any dust in the body around the sensor, remove it with a brush if necessary.
After cleaning, turn on the robot and start a test cleaning, and if it still doesn't navigate well, maybe the laser module isn't calibrated, in which case resetting the settings through the Mi Home app will help:
Settings → Device → Reset the card → Reset the robot⚠️ Note: Do not use cotton swabs to clean. LDS! The villi can stay on the glass and distort the signal even more. Also, don't blow on the sensor with your mouth, the moisture from the breath will settle on the lens and create a cloudy film.
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If after cleaning the laser sensor, the robot becomes worse to navigate, give it a hand. 10-15 I'll be back to the "recalibration" in the meantime. LDS adapt to the new conditions and accuracy returns.
Cleaning bumper sensors and optical sensors (cliff sensors)
The bumper sensors are located around the robot's perimeter and they go off when they hit obstacles. If they're contaminated, the vacuum cleaner can either ignore the obstacles or stop for no reason. The optical sensors (cliff sensors) are on the bottom and prevent falling from a height.
How to clean the bumper sensors:
- Turn over the robot and look at the rubber edge of the bumper, which often accumulates dust and hair.
- Carefully slap the bumper on the side (usually it is attached to the latches) and remove it.
- Wipe the sensor contacts with a dry wipe. If there are greasy spots, use an alcohol napkin.
- Check the bumper spring mechanisms – they should move freely.
Cleaning of cliff sensors (optical sensors):
- Find small round or rectangular windows on the bottom of the robot (usually their 4-6 piece).
- Dry them with a dry microfiber. If there is persistent contamination, use alcohol.
- Blow the holes with compressed air to remove the dust inside.
After cleaning, check the operation of the sensors:
Put your hand up to the bumper, the robot has to stop.
- Hang him over the stairs - he has to "retreat" back.
| Type of sensor | Signs of pollution | How to clean | Frequency of cleaning |
|---|---|---|---|
| Laser (LDS) | Imaculate map, chaotic movement | Compressed air + soft brush | 1 time 2-3 weeks |
| Bumper sensors | Not responding to collisions | Alcohol wipes, spring checks | 1 time per month |
| Cliff sensors. | Falling down stairs, ignoring the thresholds | Microfiber + compressed | 1 time 3-4 weekdays |
| gyroscope | Spinning around, "drunk" driving | Reboot, calibration in the annex | Failures |
What if the bumper doesn’t work after cleaning?
Cleaning of the gyroscope and charge sensor: nuances and features
The gyroscope and accelerometer are responsible for the robot's orientation in space, and their failures are manifested in the form of drunken driving when the vacuum cleaner spins in place or moves in an arc. Unlike other sensors, they can't be physically cleaned, only software calibration helps.
How to reset a gyroscope:
- Place the robot on a flat surface (for example, on a table).
- Press the power button for 10 seconds until you hear the beep.
- Open the Mi Home app and go to Settings → Calibration of the gyroscope.
- Follow the instructions on the screen (usually wait for the screen to be completed). 1-2 minute).
The charge sensor is located on the contact pad of the robot and the docking station, and if the vacuum cleaner is not charging well or not returning to the base, the reason may be oxidation of the contacts.
- 🔌 Wipe copper contacts on robot and station with an alcohol napkin.
- 🔍 Check if there are any foreign objects in the connector (hair, dust).
- 📏 Make sure the robot is snugly attached to the base (the distance between the contacts should be no more than that). 1-2 mm).
If after cleaning the charging problems remain, try resetting the base settings:
Settings in Mi Home → Docking Station → Resetting settings💡
The calibration of the gyroscope should be done on a perfectly flat surface, so if the robot is standing at an angle, the calibration will go wrong, and the navigation problems will intensify.
Frequent mistakes when cleaning sensors and how to avoid them
Many users make mistakes that harm the robot vacuum cleaner instead of benefiting, and the most common ones are:
- 🧹 Using a vacuum cleaner to clean sensors leads to static electricity, which attracts even more dust.
- 💦 Wet cleaning without drying - moisture corrodes contacts and spoils optics.
- 🔧 Disassembly of the robot without turning off - can lead to a short circuit.
- 🧴 The use of aggressive cleaning products (acetone, gasoline) - they corrode plastic and rubber.
- 🤏 Pressing too hard when cleaning – you can damage fragile sensors.
Another common mistake is ignoring firmware updates, and new software versions often fix bugs related to sensors. 3.5.8_004026 For Mi Robot Vacuum-Mop 2 Pro was fixed by a bug with false positives of cliff sensors.
If you are not sure about your abilities, you should contact the Xiaomi service center, especially models with ultrasonic sensors (for example, Mi Robot Vacuum-Mop 2 Ultra), which require professional calibration.