What is LEGO Smart Brick used for and what can you build with it?

If you're wondering What is LEGO SMART BRICK used for?The short answer is that it transforms classic LEGO bricks into pieces capable of reacting to light, sound, and movement, without the need for screens or apps. The long, and much more interesting, answer is that this is LEGO's most ambitious attempt yet to bring its classic system into the realm of electronics without sacrificing its analog essence.

LEGO has been flirting with digital technology for years, but with SMART Brick and the new SMART Play System He dares to put sensors, microphones, and chips inside a standard 2x4 brick. The result is a brick that detects its movement, its surroundings, and the characters in the scene, reacting with light and sound effects that accompany the story the child (or adult) is imagining.

What exactly is LEGO SMART BRICK and the SMART Play system?

LEGO officially unveiled its platform SMART Play System at CES in Las Vegas, describing it as the most important evolution of its gaming system since the arrival of the minifigure in the late 70s. The goal is for the usual physical constructions to be able to react in real time through lights, sounds and interactive behaviors, without breaking the free building logic that has defined the brand.

Within that system, the technological heart is the SMART BrickIt's a classic 2x4 brick that looks like any normal piece on the outside, but inside it's a different story. This block integrates a tiny custom chip, smaller even than a standard LEGO stud, along with motion, light, and sound sensors, an LED matrix, and a miniature speaker capable of generating audio effects on the fly.

Unlike other technological proposals from the company, such as Mindstorms or experiments with augmented reality, here the The electronics are completely hidden. inside the brick, so the player doesn't see any cables, screens, or strange modules. What they have in their hands are still interlocking bricks, but now with the ability to react to how they are handled.

LEGO insists that SMART Play is not an add-on accessory, but a platform designed to last for decades with the rest of the brick system, compatible with both 1958 bricks and those yet to come. The company even says that this system is designed for the "next century of play" with LEGO.

System components: SMART Brick, SMART Tags, and SMART Minifigures

The entire ecosystem of SMART Play System It's organized around three elements that work together: the SMART Brick, the SMART Tags, and the SMART Minifigures. The idea is that you don't buy individual gadgets, but rather pieces that integrate seamlessly into any construction.

El SMART Brick It's the operations center. It functions as the brain and loudspeaker of the scene: it receives data from its own internal sensors, detects which tags and characters are nearby, and, based on that, triggers sequences of lights and sounds. It reacts when it turns, shakes, tilts, or enters a moving structure, such as an airplane or a vehicle.

Beside him are the SMART TagsThese are 2x2 tiles with unique digital identifiers. These tags tell the brick what kind of object or context it's representing: a birthday cake, a spaceship's cockpit, a villain's throne, or any other scenario. By bringing them close or placing them in specific positions, the system recognizes the situation and adjusts its behavior, changing sounds, light patterns, or other effects.

Finally, there are the SMART MinifiguresMinifigures with a digital component that incorporates "personalities" and moods. When one of these figures enters the game, the system can respond differently depending on whether it is, for example, a hero, a villain, or a neutral character, generating combinations of reactions that vary according to who sits on the throne, who pilots the ship, or who participates in the scene.

LEGO emphasizes that these three elements are not separate toys, but parts of the same language: pieces that connect physically as always, but that now also "recognize" each other digitally to generate richer behaviors without complicating the user's life.

Internal technology: sensors, sound and lights without screens

One of the key decisions of the SMART Play project has been to do without screens, cameras, and artificial intelligence. Although the brick includes a microphone, LEGO has made it clear that It is only used as an input sensor to detect blows, knocks or certain noises, without recording or sending audio anywhere.

Inside the SMART Brick we find a low-power microprocessor and various inertial sensors, such as an accelerometer and gyroscope, which allow the brick to detect with considerable accuracy whether it is being shaken, rotated, tilted, or is part of a moving structure. Thanks to a color scanner and light sensors, it can also react to changes in the environment, such as variations in lighting or the presence of certain colors.

The audio is provided by a miniaturized speaker Connected to an internal synthesizer, it can generate real-time effects, not just play recorded clips. This allows for the creation of a dynamic soundscape: the drone of a ship's engines can vary depending on its tilt, or the roar of an engine intensifies when the model "accelerates" in the player's hand.

Simultaneously, a small LED array integrated into the brick activates lighting effects coordinated with the context and physical interaction, simulating cabin lights, explosion flashes, alarm signals, or simple blinks that accompany the action. All of this is controlled from a... internal game engine which combines sensor readings with information provided by SMART Tags and minifigures.

LEGO claims that the system has been designed with a logic of long lifespan and minimal obsolescenceFuture improvements will come through software updates that expand behaviors and sounds, without requiring hardware replacement every few years, something very relevant in the realm of electronic toys.

BrickNet and communication between smart bricks

When several SMART Bricks are used in the same construction, the following comes into play BrickNetIt uses a proprietary communication protocol based on Bluetooth Low Energy. This system allows smart bricks to detect each other, share information, and coordinate their reactions without the need for external hubs, remote controls, or mobile apps.

Thanks to BrickNet, SMART Bricks can identify their relative position and orientation with respect to other active bricks, as well as reacting to magnetic fields and the presence of certain tags or minifigures. This opens the door to setups where different parts of a scene interact in a synchronized way: for example, a hangar that vibrates and makes noise when a ship takes off, or several sections of a castle that change their atmosphere when a certain character enters.

LEGO's approach involves creating decentralized brick networkswhere each piece makes local decisions based on what it perceives, without depending on a central device. This reduces complexity for the user: there's no need to pair each brick with a mobile device or configure a complicated network; simply assemble them and start playing.

Another advantage of this architecture is that the game works completely without internet connectionNo WiFi, online accounts, or constant cloud updates are needed, which reassures many parents concerned about children's privacy and digital exposure.

The company emphasizes that behind this system there is a portfolio of more than twenty patents, including a dedicated SMART Play ASIC chip, designed from scratch to manage sound, sensors and communications within the physical limitations of a 2×4 brick.

Battery, charging and durability of the SMART Brick

To power all this electronics, the SMART Brick incorporates a internal rechargeable battery Designed to withstand long play sessions, LEGO has created a wireless charging base capable of charging multiple bricks simultaneously. This allows families with more than one set to simply place the bricks on the base when not in use and forget about cables.

In some variations or generations of the smart brick concept, charging is also considered. hidden USB-C portThis makes it easy to plug in like any other modern device. In any case, the priority has been to prevent the user from having to open battery compartments or deal with fragile screws and covers.

LEGO claims that the battery retains its functionality even after long periods of inactivityThis is a critical point for electronic toys that often sit in a box for months. The idea is that you can retrieve the set from the closet after years, charge the brick a bit, and keep playing without noticing how much time has passed.

This combination of wireless charging, good battery life, and low chip power consumption makes the SMART Brick a perfect fit for the typical LEGO play dynamic, where constructions are constantly being assembled, disassembled, and transformed. It's not a delicate object to be treated like a mobile phone, but a piece designed to withstand rough handling. impacts, drops and intensive use.

All of this reinforces the idea that the smart brick is not an ephemeral gadget, but a structural part of the brand's ecosystem, with vocation to last so many years like any other piece of plastic from the company.

Learning, creative play, and STEM skills

Beyond the light and sound show, one of LEGO's strongest arguments for justifying the SMART Brick is its educational potential. The piece opens the door to basic programming dynamics and logical thinking, either through visual interfaces like code blocks or through simplified systems of rules and reactions.

In some approaches, especially those geared towards education, the brick can be linked to applications that allow actions to be defined: if the model detects a fall, an alarm sounds; if the environment darkens, the lights turn on; if a certain character is shaken, a specific reaction is triggered. This transforms the brick into a bridge between the traditional educational robotics and the free construction game.

The big difference with bulky robotics kits is that The technology remains invisible inside the brick.allowing learning to occur much more organically. The child focuses on the story they want to tell and the model they want to build, while the logic of sensors and reactions is integrated almost unconsciously.

Education experts highlight that this type of experience contributes to the development of STEM (science, technology, engineering, and mathematics) skills, in addition to reinforcing the problem solving and critical thinkingCoordinating multiple smart bricks within the same complex structure poses a challenge even for advanced users, who may encounter scenarios where different modules interact with each other.

For many parents and educators, the value of the SMART Brick lies in the fact that It reduces the gap between purely analog fun and technical training.allowing children to learn programming and electronics concepts while continuing to play "LEGO" as usual.

Debate and criticism: threat or evolution of free play?

The arrival of the SMART Brick has not been without controversy. Some experts in childhood and play, such as the director of the Fairplay organization, have pointed out that these smart bricks could undermine what made LEGO special, shifting some of the child's initiative towards predefined response systems.

It has also been noted that the historical value of the brand has resided in the absolute freedom of creation with simple blocks, without instructions imposed by technology. From this perspective, there is a risk that electronics will condition the type of stories and structures that children create, if the most spectacular effects only appear when certain play patterns are followed.

In response to these criticisms, LEGO defends itself by arguing that SMART Play is designed for expand physical play, don't replace itThe technology is deliberately kept in the background: there are no attention-stealing screens, no internet connection is required, and the system can be used as a normal brick if the battery runs out or if you simply want to play without effects.

The company insists that its priority has been to avoid the "tablet effect" and keep the child focused on the physical pieces and creative building. The sounds and lights are intended to accompany the imagination, not to rigidly direct the action.

In fact, the very design without AI and without cameras reflects that desire to remain on the sidelines of tech hype and prioritize the security, privacy, and durability of the system, even if that means giving up certain trendy features.

Eight years of development and a long-term commitment

LEGO acknowledges that SMART Play and the SMART Brick are the result of almost a decade of workAfter studies conducted around 2017, the company identified that children expected three things from their games: social experiences, tangible consequences for their actions, and for the toy to evolve over time.

The challenge was enormous: to integrate these expectations into the classic brick system without breaking it. To achieve this, LEGO assembled a multidisciplinary team of experts in engineering, design, sound, UX, and computing, with the mission of ensuring that the constructions reacted coherently to characters, context, and physical manipulation, but without abandoning the essence of open play.

During the process, multiple prototypes were tested, and the project was nearly cancelled on several occasions due to technical and feasibility problems. A final adjustment It was the one that allowed all the pieces to fit together: reliable wireless charging, robust sensors, relative positioning between bricks, dynamic sound, and a proprietary chip fitted to the size limit allowed by a standard brick.

This effort resulted in some 25 patents related to the system, including the specific ASIC for sound and sensors, the BrickNet protocol, and the suite of technologies for recognizing tags and minifigures. All of this demonstrates that LEGO doesn't see this as a passing fad, but as a stable pillar of its ecosystem for the coming decades.

The choice of Star Wars as the first license is no accident: it combines narrative demands, a variety of settings, and a huge fan base, making these sets a perfect stress test to verify if the system can handle the strain in a universe very rich in sounds, movements, and memorable scenes.

With all this context, it becomes clearer what LEGO SMART BRICK is for: it's the piece that allows physical models to react intelligently to play, connecting sensors, sound, light and narrative within the same brick, and opening a new chapter for the brand without giving up what made it great.

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LEGO Smart Brick: This is the new smart brick that wants to revolutionize physical play

Daniel Terrasa

Editor specialized in technology and internet issues with more than ten years of experience in different digital media. I have worked as an editor and content creator for e-commerce, communication, online marketing and advertising companies. I have also written on economics, finance and other sectors websites. My work is also my passion. Now, through my articles in Tecnobits, I try to explore all the news and new opportunities that the world of technology offers us every day to improve our lives.