Summary
A Revolutionary Radar That Came Too Soon
Deep within Google’s headquarters in Mountain View, California, a secretive innovation lab known as ATAP (Advanced Technology and Projects) spent years developing a futuristic concept: Project Soli.
This ambitious project introduced radar-based gesture sensing — technology capable of detecting sub-millimeter hand movements using short-range radio waves.
Essentially, Soli was a miniaturized radar system, designed to transform how we interact with devices.
According to Google’s own description from a 2015 YouTube video, “Project Soli is developing a new interaction sensor using radar technology.
The sensor can track sub-millimeter motions at high speed and accuracy.
It fits onto a chip, can be produced at scale, and built into small devices and everyday objects.”
By 2019, Soli had made its consumer debut in the Pixel 4 and Pixel 4 XL smartphones.
Touted as a breakthrough in gesture-based input, it enabled a feature suite branded as Motion Sense and enhanced the phones’ biometric face unlock system.
Soli’s Short-Lived Moment in the Spotlight
Despite heavy promotion, the Pixel 4 lineup didn’t achieve standout commercial success.
Many critics pointed to Soli’s implementation as flawed—not due to its capabilities, but because of timing and design compromises.
The radar system required a larger top bezel, clashing with the industry trend of ultra-slim displays.
Combined with battery performance issues and the absence of a wide-angle lens (a controversial decision at the time), the Pixel 4 fell short of consumer expectations.
As a result, Google quietly abandoned Soli in the Pixel 5.
The radar hardware was nowhere to be found, and Motion Sense disappeared from future releases, as the company shifted focus to new chipsets and design language, starting with the Pixel 6 series.
A Brilliant Tech That Was Overshadowed
Even though it didn’t shine in the market, Soli itself was an impressive piece of engineering.
While the gesture controls (like waving to skip songs or silence alarms) were often considered gimmicky, Soli’s integration with facial recognition was genuinely innovative.
Thanks to the radar’s ability to detect when a user was approaching the phone, Soli allowed the Pixel 4’s biometric system to prepare in advance.
The result? Near-instant facial unlock that worked seamlessly in all lighting conditions — something many current phones still struggle to achieve.
The Case for a Soli Comeback
The misconception that Soli consumed excessive space in the phone’s forehead is misleading.
In reality, the radar chip was just a small component among others like the IR camera, dot projector, ambient light sensors, and the front-facing camera.
Today, smartphone technology has evolved significantly — with under-display sensors, smaller cutouts, and space-efficient designs becoming the norm.
Apple’s Face ID, now embedded in the slim Dynamic Island, proves that advanced biometric tech can coexist with modern form factors.
This progress opens the door for Soli to return in a more compact and refined format — perhaps embedded beneath the display or within a smaller housing — without compromising aesthetics or screen-to-body ratio.
Looking Ahead: Pixel 11 and the Potential of Soli 2.0
As the Pixel series matures, reintroducing Soli could differentiate Google’s smartphones in meaningful ways.
A new iteration of Soli could not only revive fast, secure facial recognition, but also unlock smarter gesture controls built on refined machine learning.
Imagine a Pixel 11 with Soli-enhanced interaction — a phone that wakes up the moment you reach for it, recognizes your face instantly in any condition, and offers intuitive, practical gestures that complement your daily routine.
With today’s hardware maturity, this vision is more achievable than ever.
Project Soli was an example of Google’s boldness in blending hardware and software innovation.
It might have arrived too early for the market to fully appreciate its value, but that doesn’t mean its story should end.
With modern advancements and the right implementation strategy, Soli can be more than a footnote in Pixel’s history — it can be its next defining feature.