THAMTU T21: A Super Slim and Powerful Robot Vacuum Cleaner with Lidar

The Thamtu T21 robot vacuum cleaner is a new product for 2023. Its main highlight is its laser navigation, which is only 7 cm tall. It also boasts a claimed suction power of up to 3500 Pa and a wet cleaning function. The most important thing is the price, which is between $160-$200, or $200-$250 at the exchange rate at the time of writing. Overall, at first glance, the robot has some very strong points compared to competitors in this price range. So, I thoroughly tested the Thamtu T21, demonstrated its capabilities, and then expressed my opinion on whether the robot vacuum cleaner is worth the money. Let's get to the review!

Equipment

The robot vacuum cleaner arrived in a branded box like this:

The package includes:

1. Charging base.
2. Power adapter.
3. Nozzle for wet cleaning with a cloth installation.
4. Spare napkin.
5. Two spare side brushes.
6. Spare HEPA and foam filters.
7. Operating instructions in English.

The kit is well-equipped. It includes all the necessary consumables for the robot's initial use.

Appearance

Now let's take a look at the design of the Thamtu T21 robot vacuum cleaner. It comes in black. The finish is glossy, which isn't very practical. The body is round and about 72 mm high.

A static lidar sensor is installed on the front mechanical bumper, which is responsible for navigation.

The robot is equipped with two mechanical buttons. The combined dust container and water tank are removable from the rear. It conveniently stores the cleaning tool. The tank holds up to 300 ml of water. The amount of water flowing to the cleaning cloth is electronically adjustable. The dust container has a capacity of 250 ml. The filtration system is triple: mesh, foam, and HEPA filters.

The rear of the container has terminals for connecting to the self-cleaning station, as well as a dustbin for emptying the container. Unfortunately, the seller states that the station cannot be purchased separately. This same model with a self-cleaning station is sold as the Thamtu T21s. This attachment with a cleaning cloth is attached to the robot. Water flows through three holes. The cleaning cloth is attached to the attachment with Velcro.

The robot has four fall protection sensors installed underneath. It also has two side brushes, three-beam and quick-release.

The central brush unit is non-floating. The turbo brush itself is made of bristles and petals. Both sides can be removed to remove tangled hair and pet hair.

Overall, considering the price, there are no particular complaints about the robot's design.

Technical specifications

The main characteristics of the Thamtu T21, as stated by the manufacturer, are displayed on the screen:

• Li-Ion battery 5200 mAh.
• Suction power up to 3500 Pa.
• Operating time up to 180 min.
• Dust collector 250 ml.
• Water tank 300 ml.
• Dimensions: 350*72 mm.
• Weight: 3.4 kg.

It's worth highlighting the capacious battery and increased suction power, which will be verified in tests.

Functional capabilities

Regarding the capabilities of this robot vacuum cleaner, it is controlled via the proprietary Thamtu mobile app. The interface is in Russian, and connection was straightforward.

The main functions of Thamtu T21 are displayed on the screen:

• Save up to 5 cleaning maps.
• Automatic zoning of premises into rooms.
• Selecting areas and rooms for cleaning.
• Virtual walls and no-go zones.
• Prohibited areas for wet cleaning.
• Suction power adjustment.
• Adjusting the water supply level.
• User mode.
• Double pass mode for the entire area.
• Cleaning log.
• Setting up cleaning according to a schedule.
• Voice notifications in Russian.
• Resume cleaning after charging.
• Automatic power increase on carpet.
• Yandex.Alice support.

I was pleased with the functionality. It includes all the basic features for flexible cleaning settings, which is a plus.

Testing

A detailed video review of the Thamtu T21, including all tests, has already been published on the channel:

Navigation

And finally, let's move on to the tests. First, we'll test the Thamtu T21's navigation in a room with obstacles. Upon entering the test zone, the robot vacuum cleaner begins cleaning the designated area in a serpentine pattern. It moved over the legs of the dryer without getting stuck. It also cleaned around the box and chair legs. It did move the box, however, and it's clear that its contact with objects isn't very precise, despite the lidar sensor on the bumper itself. Furthermore, the robot didn't complete a control walk around the perimeter.

Speaking of indoor navigation, I'll first show you how a hidden static lidar works. You can see that mapping is fast, in real time. Unlike a rotating lidar, which scans a room 360 degrees, a static lidar only scans the area in front of it, meaning the robot needs to rotate to scan the entire area around it. This system has both pros and cons. On the plus side, static lidar is more durable since there are no moving parts. However, the downside is that the robot cleans more slowly and less thoroughly. In our test, the Thamtu T21 cleaned room after room in a serpentine pattern. Again, it didn't complete the perimeter. And this is the first serious criticism I have of the robot. It performs worse along walls and furniture.

Another point regarding navigation: If the robot first builds a map, and then you close the door to one of the rooms during the next cleaning, it will draw a boundary at the entrance. After that, you won't be able to select that room for cleaning when you open the door until the robot rescans the entire room in automatic cleaning mode and removes the boundary. This is very inconvenient. Another observation: if you move the base to a different location, the map is rebuilt. This means the robot has a poorer understanding of its position on the map.

In the end, I can say that the navigation is better than that of inexpensive robot vacuum cleaners with a camera, but definitely inferior to a regular rotating lidar.

Suction power

The suction power was impressive. The Thamtu T21 was able to suck up debris from every crevice, including those as deep as 10 mm. This is definitely a powerful, slim robot vacuum!

Dry cleaning

The collection performance of various types of debris on laminate floors is good. Only a little debris remains in corners, where round robotic vacuums can't reach. A few hairs and fur got caught on the brushes, but most of the debris was collected in the dust bin. Test passed!

Carpet cleaning

Carpet cleaning performance is average. The robot is unable to remove small amounts of hair and pet hair from the carpet. This is likely due to the non-floating center brush unit.

Wet cleaning

There are no particular complaints about wet cleaning. The Thamtu T21 was able to remove dried-on dirt from the floor, leaving only minor streaks and a small area with a dirty streak along the baseboard. However, this last point is similar to the results of all other similar devices tested. Overall, the wet cleaning performance is average.

Wet cleaning and carpets

Regarding wet cleaning on carpets, the Thamtu T21 cannot automatically avoid carpets when the cleaning pad is attached. Therefore, it's best to protect them with separate no-go zones for wet cleaning mode.

Obstacle clearance

Obstacle clearance isn't very good. The robot can still navigate a 15mm threshold, but it gets stuck at 20mm. But given the robot's relatively small frame, this is to be expected.

Driving through black surfaces

There are also issues with driving over black surfaces. The robot detects elevation changes on black carpets and avoids them. However, there are no issues on hard black surfaces. This is important to keep in mind.

Noise level

The noise level ranges from 62 to 71 dB, depending on the selected mode. Considering the high suction power, the noise level is acceptable.

Personal opinion

The Thamtu T21 robot vacuum cleaner has been thoroughly reviewed and tested. our evaluation system he managed to gain 100 points, losing by only 1 point to its main competitor Xiaomi Mijia Ultra-Thin Robot Vacuum Cleaner, which also boasts a very thin body. In any case, the result is good, considering the price and features.

Overall rating of tested robot vacuum cleaners: https://robovac.washerhouse.com/en/rejtingi/robovac-obshhij-rejting-robotov-pylesosov-robo.html.

I'll share my personal opinion of the robot after testing it. I liked the following:

1. The presence of a hidden static lidar.
2. Small body height.
3. High suction power.
4. Capacious battery.
5. Simultaneous dry and wet cleaning.
6. A large number of functions in the application.
7. Full Russification of both the application and voice notifications.
8. Good equipment.
9. Optimal price considering the capabilities and navigation.

As for the shortcomings, the following comments were found about the robot:

1. Does not clean the perimeter of the room.
2. Careless touching of objects.
3. Afraid of black carpets.
4. Poor cross-country ability.

Ultimately, we see that this model has both pros and cons. In any case, the Thamtu T21 is worth considering if you're looking for a slim robot vacuum or simply an affordable model under $200. Cleaning quality is quite acceptable, and the robot is capable of cleaning large areas and has all the necessary features. If these concerns aren't critical for you, I recommend considering this model. I think the Thamtu T21 is an optimal choice for cleaning hard floors and under low furniture, with a clearance greater than 75 mm but less than 95 mm, which is beyond the reach of conventional lidar robots.

On that note, I'd like to end this review. If you have any questions, please ask them in the comments. Happy shopping. Bye!