Santa Clara, California-based Anello Photonics company and Montreal-based One Silicon Chip Photonics (OSCP) firm have introduced new gyroscope-on-a-chip navigation systems that allow for precise heading and distance tracking without satellite signals.
Optical gyroscopes were developed to replace satellite-based global navigation systems. GPS is susceptible to jamming and spoofing, disrupting navigation, or providing misleading location data.
In 2018, Caltech electrical engineering and medical engineering professor Ali Hajimiri and his team made a breakthrough that overcame the size and accuracy limitations of the 1970s optical gyroscopes.
The team created a solid-state gyroscope small enough to fit on a grain of rice and leveraged the Sagnac effect, a principle first proven in 1913 by French physicist Georges Sagnac.
The Sagnac effect happens when a beam of light is split into two and sent in opposite directions along a circular path.
When the device rotates, one beam reaches the detector ahead of the other, allowing precise measurement of the rotation angle. As this method does not work based on external signals, it is immune to electromagnetic interference, vibration, and cyberattacks through an open communication channel.
Therefore, it becomes an ideal solution for applications where GPS is unreliable.
Hajimiri and his colleagues adopted a technique for eliminating noise to create an optical gyroscope that was not only–five hundredth the size of commercially previous fiber-optic gyroscopes but also comparable in terms of sensitivity.
Anello Photonics and OSCP reshaped the navigation market with Hajimiri’s gyroscope-based systems that allow more miniaturization without diminishing the gyroscopes’ effectiveness.
Anello’s low-loss silicon nitride waveguides allow light to circulate longer within the gyroscope, enhancing signal strength and reducing error accumulation. In addition, Anello’s techniques also prevent other noise sources. They use a smaller waveguide holding less light. This means a fainter signal, but it is still sufficient for accurate rotation readings.
Mario Paniccia, Anello CEO, said his company’s inertial measurement units (IMUs), which consist of three chip-based gyroscopes and additional components, can fit in the palm of a person’s hand.
The tech can deliver high precision for multiple applications, such as agriculture, where autonomous tractors must maintain straight furrows for up to 800 meters. The system was designed specifically for unmanned underwater and surface vehicles.
Meanwhile, the OSCP founder and CEO Kazem Zandi also unveiled an upgraded multi-gyroscope IMU that is half the size of its predecessor but more power-efficient and less expensive.
