The situation where a smart assistant suddenly stops in the middle of a room and starts to sound alarms is familiar to many owners of smart equipment. The drop sensor is a critical element of the navigation system, which often causes false alarms or a complete stop of the device. If your Xiaomi Mi Robot or Roborock is stuck on a flat carpet or panics at the doorstep, the problem almost certainly lies in the optical sensors located in the lower part of the case.
Understanding these components is essential for rapid fault detection. Unlike mechanical switches, it uses infrared radiation that can be blocked by the most common dust. 90% of sensor errors are caused by contamination of the transparent sensor window with pile and dust plugs. In this article, we will look in detail at where these elements are in the various robot lines, how to properly maintain them and what to do if simple cleaning does not help.
You don't want to ignore the height break signals, because the constant false stops can cause the robot to stop cleaning the room completely. The mapping algorithm perceives the signal from the sensor as a real barrier or a floor break, which causes it to make wrong routes. Let's look at the anatomy of your gadget to restore its efficiency and accuracy.
The technology for detecting elevation differences is based on the use of infrared LEDs and photodetectors. The emitter sends a signal down to the floor surface, and if there is a solid surface within 1-2 centimeters, the beam reflects and hits the receiver. The system reads this return as "safe." If there are no reflections (for example, a robot has come up to a ladder), the controller blocks the engines, preventing the fall. In the devices of the Xiaomi Vacuum and Roborock line, an array of several such sensors, usually from three to six pieces. This allows the device to assess the presence of the floor, but only the presence of the sensor, when it is on the floor, it is a slight angle, but it does not appear. This is most often due to the fact that the infrared beam is scattered in the dust layer or absorbed by the black pile of the carpet. ⚠️ Warning: Never try to seal the sensors with tape or tape to bypass the fall protection, which will cause a real accident and the device falls from a height, which is guaranteed to disable the battery and motors. Modern models use more sophisticated signal processing algorithms, but the physical principle remains the same: If a greasy film from cleaning with detergent hits the sensor's lens, the transparency for the IR rays drops dramatically, and the robot perceives this as a lack of reflection and stops. 📊 How often do you have fall sensor errors?Once a week when cleaning carpets Only after general cleaning Constantly, the robot can not work
The search for sensors always starts at the bottom of the device. Most of the robot vacuum cleaners Xiaomi and Roborock are unified, but there are nuances depending on the generation. 1S or 2 Pro, drop sensors are small black or transparent plastic windows embedded in the body next to the main wheel and side brush. Usually there are three: one in front in the center and two on the sides in front of the bottom. In more advanced models equipped with wet cleaning function, such as Roborock S5 Max or Xiaomi Mop 2 Pro, the number of sensors can be increased to four or five to more accurately track the position of the water tank above the carpets. For an accurate location in your model, refer to the table below, which provides data on popular modifications: Robot model Location Protection Type Mi Robot 1S 3 pieces. Front part, triangle Open lenses Roborock S5 6 pcs. Around the perimeter of the bumper Received Xiaomi Mop Essential 3 pcs. Along the front edge Protective grid Roborock S7 MaxV 5 pcs. Shifted to the centers of the wheels Anti-Stick If you flip the device and do not see the obvious black eye, some of the sensor may need a cleaner, for example, the X-s, the X-Pac, the X-Pac, the X-Pac, the X-Sensorpppex, the XPacularity range may be hidden under the XPac.
The most effective and safe way to restore performance is a thorough cleaning. You will need a dry waxless wipe, cotton swabs and possibly isopropyl alcohol. Water for this procedure is not recommended, as it can leave wiring that will also distort the signal. The cleaning process must be delicate. Do not use sharp objects such as needles or scissors to pick through the sensor holes. You can scratch the lens or damage the internal wiring, which will lead to the need to replace the entire 5-10 module, which will also help with a clean the front of the glass. Moisture residues can create a lens effect and distort the angle of reflection of the beam. Pay special attention to the side sensors, as they are most often clogged with dust swept away by the side brush. Pile can be tightly tamped into the protective net. In such cases, it is convenient to use a can of compressed air to blow contaminants from the depth of the body.
In cases where cleaning does not help, the emitter or receiver itself probably failed, or the plume has gone away. Replacement will require partial disassembly of the bottom cover. You will need a cross screwdriver (usually PH0 or PH1) and a plastic blade to open the latch. First remove the side brush and the main turbobrush. Then unscrew all visible screws on the bottom panel. Be careful: some screws can be hidden under rubber legs or on the 5th module. Remove the battery before the sculp and remove the sensor from the mainboard. 3. Replacing requires care, as the plumes in Xiaomi devices are quite thin and easily break if you carelessly handle. If you are not sure about your soldering skills or working with small electronics, you should order a service from a service center. However, if the problem was in the contact cliff, a simple soldering or replacement of the plume will bring the robot back to life.
It's not always the fault of the machine. Black glossy surfaces, dark carpets with high pile and mirrors on the floor can cause problems. Black absorbs infrared radiation, and the sensor "does not see" the reflection, believing that there is emptiness under the robot. This is a routine security behavior, not a breakdown, and if the house has dark floors, owners often find that the robot refuses to clean certain areas. In such cases, it helps to adjust virtual walls in the application to limit the cleaning area, or use special magnetic tapes (if the model supports). Some users go for a trick and stick small pieces of light tape on the black areas of the floor, but this is a temporary solution. 🌑 Deep black carpets can be perceived as a chasm. 🪞 Mirror surfaces create false reflections of the signal. 🌫️ Transparent glass (tables, windows) robot can ignore or take for a hole. 🧶 A long pile can physically block light from reaching the sensor, and understanding the limitations of optics helps to properly zoning the space. If the robot is constantly "afraid" of your favorite black carpet, maybe you should start cleaning only light areas or accept that this area will have to be vacuumed by hand. Can you turn off the fall sensors software? Standard software Xiaomi and Roborock do not have such a feature. It's done for safety reasons. There are modified firmware (like Valetudo for re-enhanced devices) that allows you to ignore the sensors, but it's a security breach and creates a risk of the device falling? If the threshold height exceeds the calibration limit (usually 1.5-2 cm), the robot may not have time to react, especially when reversing or at high speed. This also happens when the wheels wear out, when the clearance increases. How to check the sensor without disassembling? Turn the robot over, turn it on and hold the palm of your hand to the black windows at the bottom. If the sensor is working, you will hear a characteristic click or change in the tone of the sound signal, and the application may display the status of "raised".