This year, two companies - Anello Photonics in Santa Clara, California, and One Silicon Chip Photonics (OSCP) in Montreal - introduced new on-chip gyroscope navigation systems that enable precise heading and distance tracking without satellite signals.

This inertial navigation is increasingly important today because GPS is susceptible to jamming and spoofing, which can disrupt navigation or provide misleading position data. These problems have been well documented in conflict zones such as Ukraine and the Middle East, where military operations face severe GPS jamming. For drones that rely on GPS for positioning, signal loss can be catastrophic, rendering them unable to navigate and sometimes even causing crashes.

Optical gyroscopes have long been considered an alternative navigation technology to satellite-based global navigation systems. Large devices such as ring laser gyroscopes have been around since the 1970s. However, shrinking these devices to chip size is easier said than done.

Optical gyroscopes produced since the mid-1970s have difficulty maintaining the light signal strength required for precise rotation sensing. Shrinking them only makes the signal-to-noise ratio worse. So while most microelectronic devices have followed the path of miniaturization described by Moore's Law, light-based gyroscopes have remained large, bulky, and power-hungry.

Size and precision limitations

That is until Ali Hajimiri, a professor of electrical engineering and medical engineering at Caltech, and his team made a breakthrough that overcame previous size and precision limitations. In a 2018 paper, they described how to create a solid-state gyroscope small enough to fit on a grain of rice. Like optical gyroscopes before it, this one exploits the Sagnac effect, first demonstrated in 1913 by French physicist Georges Sagnac.

The Sagnac effect occurs when a beam of light is split into two and sent in opposite directions along a circular path. If the device is rotated, one beam reaches the detector before the other, allowing the angle of rotation to be precisely measured. Because this approach doesn't rely on external signals, it's immune to electromagnetic interference, vibrations, and cyberattacks over open communications channels—making it an ideal solution for applications where GPS is unreliable or denied altogether.

By introducing a technique to eliminate noise, Hajimiri and his colleagues were able to create an optical gyroscope that's one-five-hundredth the size of commercially available fiber-optic gyroscopes, but with comparable sensitivity.

Anello and OSCP enter the market

Less than a decade after Hajimiri's breakthrough, Anello Photonics and OSCP are trying to reshape the navigation market with their gyroscope-based systems. They've introduced further improvements that allow the gyroscopes to be even more miniaturized without compromising their effectiveness. Anello's low-loss silicon nitride waveguides allow light to circulate inside the gyroscopes longer, which improves signal strength and reduces error accumulation. Anello's technology further suppresses other noise sources, so that smaller waveguides can hold less light (and therefore weaker signals) but still be enough to get accurate rotation readings.

Anello CEO Mario Paniccia said the work was shown at CES in 2024 and earlier this year. Paniccia explained that his company's inertial measurement units (IMUs) consist of three chip-based gyroscopes and other components that can be held in the palm of your hand. They provide high accuracy for a variety of applications, including agriculture, where autonomous tractors must maintain perfectly straight furrows for up to 800 meters. Longer distances are also not a problem for the navigation system, he said. "If you drive 100 kilometers," Paniccia said, "the system will measure distance to within 100 meters, or 0.1% of the distance driven."

 OSCP is also making strides in miniaturized navigation technology. At CES 2025, OSCP founder and CEO Kazem Zandi unveiled an upgraded multi-gyro IMU that is half the size of the previous generation. "Not only is it smaller, it's more energy efficient and cheaper," Zandi said at the tech expo in Las Vegas. "These gyros can provide dead reckoning with centimeter-level positioning accuracy."

IMU of Anello and OCSP

Anello and OCSP's IMUs are designed to work in conjunction with GPS, constantly monitoring position inputs. If GPS interference is detected, the artificial intelligence (AI) within both companies' systems automatically transfers navigation control to the gyroscope. "For example, if you're in New York," Paniccia explained, "and the gyroscope says you've traveled 100 meters forward, but the GPS says you're now in Texas, then the algorithm knows to transfer control to [the gyroscope]."

Anello's latest system is designed for unmanned underwater and surface vehicles that navigate the vast open ocean with no landmarks to aid navigation, according to Paniccia. "In the ocean, everything looks the same," he said. In ocean space, currents make navigation more complicated than tracking position on land or in the air, and Paniccia said the Anello device's positioning error is more like 3 or 4 percent of the distance traveled.

Paniccia said he envisions a future where tiny gyroscopes could be embedded in firefighters' handheld devices to help them navigate smoke-filled buildings where stairways and exits are no longer visible. "It's essentially an electronic compass," he said.

Source: Content compiled from IEEE

Reference link https://spectrum.ieee.org/optical-gyroscopes-on-chip

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