Stop me if you’ve seen this before: a black and white pixelated square in place of a physical menu at a restaurant.
QR codes seem to be common in everyday life. Whether you see a code on a coupon at the grocery store, a flyer on a bulletin board, or a wall at a museum exhibit, each code contains embedded data.
Unfortunately, QR codes in physical space are sometimes substituted or spoofed to trick you into giving your data to unwanted parties — a seemingly innocuous set of pixels that can lead you to dangerous links and viruses. Researchers from MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) have developed another potential alternative: BrightMarker, an invisible fluorescent tag hidden in 3D printed objects, such as such as balls, containers, utility boxes, or gears. The researchers believe their system can enhance motion tracking, virtual reality, and object detection.
To create BrightMarker, users can download the software plugin of the CSAIL team for 3D modeling programs like Blender. After placing the tag in the design’s geometry, they can export it as an STL file for 3D printing. With fluorescent filaments fed into the printer, users can craft an object with a hidden tag, like an invisible QR code. Users will need to embed their markers in an object before it is crafted, meaning tags cannot be added to existing items.
Fluorescent materials allow each tag to emit light at a specific near-infrared wavelength, making them viewable with high contrast in an infrared camera. The researchers designed two pluggable hardware setups capable of detecting BrightMarkers: one for smartphones and one for augmented reality (AR) and virtual reality (VR) headsets. Both are capable of viewing and scanning QR code-like markers that glow in the dark. Surrounding objects can be obscured from view using a long-distance filter, another mountable unit that detects only fluorescence.
BrightMarkers are invisible to the naked eye — and are unobtrusive, meaning they do not alter the shape, appearance, or function of the subject. This makes them tamper-proof while seamlessly embedding metadata in the real world. By adding an extra layer of connectivity between data and physical objects, users gain access to a more interactive experience with the world around them.
“In today’s rapidly evolving world, where the lines between physical and digital environments continue to blur, there is a growing need for powerful solutions that seamlessly connect physical objects. management with their digital counterparts,” said MIT CSAIL and the Department of Electrical Engineering and Digital Science. Computer Science PhD candidate Mustafa Doğa Doğan. “BrightMarkers serves as a gateway to ‘pervasive metadata’ in the physical realm. The term refers to the concept of embedding metadata — descriptive information about an object’s identity, origin, function, etc. — directly into physical items, like an invisible digital signature. included with each product.”
BrightMarkers in action
Their system made promise in virtual reality settings. For example, a toy lightsaber with an embedded BrightMarker can be used as an in-game tool to slice through a virtual environment, using tag detection hardware. This tool can activate other objects in the game for a richer VR experience.
“In a future dominated by AR and VR modeling, object recognition, tracking and traceability are crucial to connecting the physical and digital worlds: BrightMarker is just the beginning, ” said Raúl García-Martín, visiting researcher at MIT CSAIL, who is doing his research. PhD at the Carlos III University of Madrid. “BrightMarker’s seamless tracking marks the beginning of an exciting journey towards a technology-powered future.”
For motion tracking, BrightMarkers can be deployed into wearables that can accurately track limb movements. For example, a user can wear a bracelet with an implanted BrightMarker, which allows a piece of hardware to digitize the user’s movement. If a game designer wanted to develop an authentic first-person experience, they could model the hands of their characters after accurately tracking each marker. The system can also assist users with disabilities and different limb sizes, bridging the gap between digital and physical experiences for many users.
BrightMarkers can also be tracked in the supply chain. On-site manufacturers can scan tags in different locations to get metadata about the product’s origin and movement. Likewise, consumers can check a product’s digital signature to verify ethical sourcing and recycling information, similar to the Alliance’s proposed Digital Product Passport. Europe.
Another potential use: night vision monitoring in home security cameras. If users want to ensure their possessions are safe overnight, a camera can be fitted to track objects using hardware designed to track and notify the owner of any movement. any. Unlike similar products available, this camera will not need to capture the user’s entire room, thus protecting their privacy.
Better than InfraredTags and AirTags
The work of Doğan and his team sounds familiar: they previously developed Infrared Tags, a technology that embeds data on 3D printed tags in physical objects, nominated for a Demo Award Best voted by people at ACM CHI 2022 Conference on human factors in computer systems. Although their previous project only worked with black objects, users have many color options with BrightMarker. With fluorescent materials, the tags are configured to emit light at a specific wavelength, making them much easier to isolate and track than Infrared Tags, which can only be detected at low wavelengths. low contrast due to noise from other wavelengths in the captured environment.
“Light-emitting fluorescent fibers can be intensely filtered by our imaging hardware,” says Doğan. “This overcomes the ‘blur’ typically associated with traditionally embedded discreet markers and enables effective real-time tracking even when subjects are in motion.”
Compared to Apple’s AirTags, BrightMarkers are low cost and low in power. However, depending on the application, one potential limitation is that tags cannot be added to existing post hoc objects. In addition, tracking each tag can be impeded if the user’s hand or other object in the room obstructs the view of the camera. The team recommends combining this technology with magnetic fibers to be able to track the object’s magnetic field as a remedy to enhance detection. The detection performance of the tracer can also be improved by creating fibers with a higher concentration of fluorochrome.
“Fluorescent object tracking markers like BrightMarker hold great promise in providing a potentially practical solution for tracking,” said Andreea Danielescu, director of Future Technology Research and Development at Accenture Labs. product tracking and authentication. they can also be used to verify the authenticity of a product, such as a vegan handbag.”
“Immersive technologies require strong scene understanding,” said Google research scientist Mar Gonzalez-Franco, who was not involved in the work. “Embedding invisible markers, such as those from BrightMarker, can simplify computer vision needs and help devices identify interactive objects and bridge the gap for AR and VR users.”
Doğan is optimistic about the system’s potential to connect metadata in our daily lives. “BrightMarker holds great promise in reshaping our real-life interactions with technology,” he notes. “As this technology continues to advance, we can envision a world where BrightMarkers are seamlessly integrated into our everyday objects, facilitating easy interactions between objects. physical and digital domains. From retail experiences where consumers can access detailed product information in stores to industrial facilities, where BrightMarkers streamlines supply chain tracking, the possibilities are vast. “
Doğan and Garcia-Martin wrote the paper with MIT CSAIL undergraduate students Patrick Haertel, Jamison O’Keefe, Ahmad Taka, and Akarsh Aurora. Raul Sanchez-Reillo, professor at Carlos III University of Madrid, and Stefanie Mueller, a CSAIL affiliate and associate professor in MIT’s department of Electrical and Computer Science and Mechanical Engineering, are also authors. . The researchers used a fluorescent filament supplied by DIC Corp. They will present their findings at the Computer Society’s 2023 User Interface Software and Technology Symposium (UIST).