Modern smart cleaning models from Xiaomi and sub-brands like Roborock, Dreame or Viomi are able to navigate the space themselves. However, many users are faced with the fact that the device “forgets” the layout of the apartment or builds a map anew every time you start, understanding the principles of lidar and optical sensors allows not only to solve the problem, but also to optimize the cleaning routes.
The mapping process is a complex algorithm that depends on the state of the sensors, the lighting and the correct settings in the Mi Home application. If the robot vacuum cleaner can not create a static map, it goes into chaotic mode of movement, which significantly reduces the efficiency of cleaning and increases battery life. In this article, we will discuss the technical aspects of creating maps, methods for saving them and solving frequent errors.
So the basic principle is that a permanent map is formed after only a few complete cleaning cycles. The initial run is often exploratory. The device scans the perimeter, detects obstacles, and creates a point cloud, which then turns into a two-dimensional floor plan, and without that, you can't use advanced features like room division or virtual exclusion zones.
The principle of operation of the LDS navigation system and VSLAM
Most modern Xiaomi models have a laser rangefinder (LDS) on the top panel, which rotates and emits beams to measure the distance to walls and furniture, and a VSLAM (visual navigation) system that uses a camera to recognize the texture of the floor and position in space, and it is the combination of these technologies that allows you to build accurate maps.
If a robot vacuum cleaner starts spinning in place or building a map anew, the problem is often the sensors get dirty. The laser module requires cleanliness, because even a thin layer of dust distorts distance measurements. Also important is the condition of the side turbo brush, which can mechanically interfere with the rotation of the laser tower.
There are several key factors that affect the quality of the scan:
- 🔦 Lighting: For cameras VSLAM Light is critical; in complete darkness, navigation can be disrupted.
- 🪞 Reflective surfaces: Mirrors and glossy facades confuse lidar, making the robot think there is an extension of the room.
- 📡 Wi-Fi signal: A weak signal prevents you from uploading the card to the cloud, which may not save it after cleaning.
⚠️ Warning: Do not put protective films on the laser dome or paint over the sensor holes, which leads to irreversible positioning errors and failures in the construction of the route.
Step-by-step: first start and create a map
To make Xiaomi Robot Vacuum remember the map correctly, you need to properly prepare the room: remove wires, socks and small objects that can get stuck in the wheels from the floor; doors to rooms that should be part of the map should be opened; start the process better in the afternoon when the lighting is as bright and stable as possible.
Once you've connected to your Wi-Fi and linked to your Mi Home account, go to your robot settings. Find the Settings card or Map. If you already have a card but it's incorrect, you need to delete it. To do that, select Delete the card and confirm the action. Now the robot is ready for a clean start.
☑️ Preparation for the first map construction
Run Quiet Cleaning or a special Build Map mode if available in your model. Don't interrupt the process even if the robot has finished cleaning one room - it must return to base on its own. Only after a successful return to base and completion of the cycle will the data be recorded in the device's memory.
Configure virtual walls and zones in the Mi Home app
Once the map is saved, you can access a fine-tuning, so you can divide the space into separate rooms, and in the map editing mode, select the "Separate" tool and draw a line in the doorway, which allows you to set the cleaning modes for each zone individually.
Virtual walls and no-go zones are powerful tools for protecting certain areas, such as not allowing a robot to go under a sofa with low clearance or into an area where a pet's water bowl is located, and settings are made through the Zone menu -> No-go zone.
The main types of restrictions available in the interface:
- 🚫 No-go zone: The square area where the robot is not allowed to enter.
- 🧱 Virtual Wall: An invisible line that a device cannot cross.
- 🧹 Zone cleaning: Allocating a specific rectangle for spot cleaning.
💡
Use the Save a few maps feature if you have a two-story house, which allows the robot to switch between floor plans without losing data.
Remember to save the changes after each edit. Sometimes the app requires re-confirmation to update the card firmware in the robot's memory. If you've made changes to the furniture arrangement, the map is better updated through the Edit function.
Problems with saving the map and their solution
A common situation is that the robot has gone away, but the map has disappeared or moved, and this may be due to a server sync failure, check if the phone has a background restriction for the Mi Home app, and make sure that the account region matches the region of the device.
Another reason is a change in base location, and if you move the dock even 30-40 cm, the robot can lose its anchorage and start building a new map over the old one, in which case manual positioning reset or complete removal of the old map helps.
Comparison of the reasons for resetting the card:
| Reason. | Symptoms. | Decision |
|---|---|---|
| Transfer of the base | The robot can't find the base. | Delete the map and create a new one |
| Weak Wi-Fi. | The card is not loaded into the app | Install a repeater or transfer the router |
| Dirty lidar | Robot spins, map curves | Wipe the sensors with an alcohol napkin. |
| Dark time of the day | Loss of orientation (for VSLAM) | Leave a night light or light in the corridor |
⚠️ Warning: Don't move the robot vacuum cleaner with your hands while you're working. If you're taking it to get it out of the chair, make sure you put it back in the same place, or the coordinates will get lost.
Use of the Multi-Card Function
Owners of country houses or large apartments with multiple levels will benefit from the multi-card feature. Xiaomi and Roborock flagship models allow you to save up to 4 different maps. This means that you can move the robot to another floor, and it automatically recognizes the layout.
To activate this feature, go to the map settings in the app and select Save Card. Once you finish cleaning on the second floor, the system will prompt you to save the new plan.
It's important to understand that the robot only transitions between floors when it's off or when it's moved by the user. It can't climb stairs on its own. When you move the device, make sure it's off so it doesn't disrupt the current coordinates.
Can two cards be combined into one?
Cartography reset and update
If the map is damaged or contains artifacts (extra walls, ghost objects), it must be reset. In the Mi Home app, select the device, go to the settings (three dots in the corner) and find Reset the card.
Sometimes you need to update the firmware of the robot itself or the device plugin. Check the software version under General settings -> Check for updates. New navigation algorithms often come with firmware updates, improving the accuracy of route construction.
The sequence of actions in full reset:
- Remove the current card in the app.
- Clean all sensors (LDS, bumper, wheel sensors).
- Restart the router and the robot itself (on button).
- Start building the map again in good lighting.
After these steps are completed, the device must be stable, and if problems persist, it may be necessary to replace the LDS laser module, which wears out over time.
💡
The stable operation of the card depends not only on the software, but also on the physical purity of the sensors and the immobility of the base during cleaning.