Plastering a display on top of your field of vision only gets you just so far. For augmented reality (AR) applications to really impact our everyday lives, they will also need to make objects in the real world more interactive. Whether that interactivity takes the form of providing us with additional contextual information about them or the ability to control them in new ways, the first step in the process is identifying everything that is nearby.
At present, that is not an easy task. Some headsets accomplish this goal through the use of computer vision algorithms. While they work reasonably well, they require substantial computing power and consume a large amount of energy. That is not compatible with a portable platform, especially one with a small form factor like a pair of smart glasses. As a compromise, some systems instead identify objects via passive markers such as QR codes and RFID tags. These options cut down on computation and energy, but they are static, so they cannot provide up-to-the-minute or variable information.
A marker circuit board and a headset equipped with a camera (📷: X. Yang et al.)
A new option has just emerged as the result of a collaboration between UCLA and Texas A&M University researchers. They have developed what they call LuxAct, a simple and inexpensive way to identify everyday objects. By using self-powered, blinking LEDs, LuxAct can also provide important context to the AR systems that it interacts with.
The goal of LuxAct is to transform ordinary objects into digital communicators. Instead of using expensive electronics or always-on sensors, each LuxAct-enabled object uses a tiny piezoelectric generator that produces electricity when it’s deformed. When a user taps, presses, or plucks at the object, the motion produces enough energy to power a small multicolor LED. That light blinks in a specific, color-coded pattern that can be read by the point-of-view cameras already built into most AR headsets or smart glasses.
A light tap on a surface might flash one color sequence, while twisting a knob or plucking a flexible tab could generate another. The resulting bursts of red, green, and blue light encode information such as the object’s ID, its current state, or even environmental data like temperature or pressure. Because these flashes occur only during interaction, they save power while also signaling that the user is actively engaging with the object.
Prototypes built with the system (📷: X. Yang et al.)
LuxAct’s design also eliminates the need for digital components such as microcontrollers. Instead, it relies entirely on the physics of piezoelectric motion and resistance changes in simple circuits. This minimalist approach makes it ultra-low-cost, lightweight, and easy to embed into virtually anything — from medicine containers that flash dosage reminders to water hoses that report flow conditions.
The researchers demonstrated several different prototypes, including fingertip sensors, interactive control knobs, and trash containers that communicate the remaining empty space when opened. Each prototype shows how LuxAct can bridge the gap between the physical and digital worlds, without the bulk and complexity of traditional systems.
While still in an experimental stage, LuxAct opens a path toward scalable, battery-free interactivity for AR environments. Everyday items could soon identify themselves and share context using nothing more than light and a bit of motion. There are challenges left to solve, such as improving detection under bright lighting or during rapid movements, but the foundation appears to be solid.
