Tag: optical chip

Advanced Navigation launches Boreas D70 digital fiber-optic gyroscope
Photo: Advanced Navigation

Advanced Navigation has announced the Boreas D70, a fiber-optic gyroscope (FOG) inertial navigation system (INS).

The D70 is the latest release in the Boreas digital FOG (DFOG) series, offering a new performance grade with superior accuracy, exceptional stability and reliability. The technology is suited to surveying, mapping and navigation across subsea, marine, land and air applications.

“We are thrilled to expand the Boreas series with the D70. It’s a system that will provide additional flexibility in the Boreas family, making ultra-high accuracy inertial navigation far more affordable than with previous FOG INS systems,” said Xavier Orr, CEO and co-founder of Advanced Navigation. “This patented technology opens the possibility for adopting FOG INS systems across a much broader range of vehicular applications, particularly autonomous vehicles and aircraft where weight and size are at a premium.”

Boreas D70 combines closed-loop DFOG and accelerometer technologies with a dual-antenna real-time kinematic (RTK) GNSS receiver. These are coupled with Advanced Navigation’s artificial-intelligence-based fusion algorithm to deliver accurate and precise navigation.

The system features ultra-fast gyrocompassing, acquiring and maintaining an accurate heading under demanding conditions. While the D70 does contain a GNSS receiver, it is not required for gyrocompass operation.

Based on the company’s DFOG technology, the D70 delivers a 40% reduction in size, weight, power and cost (SWaP-C) when compared to systems of similar performance.
- 0.01° roll and pitch
- 0.1° secant latitude heading (gyrocompass)
- 0.01°/hour bias instability
- 10 mm position accuracy
The Boreas Series

The Boreas DFOG series features ultra-fast gyrocompassing and can acquire heading, either stationary or dynamically, in less than two minutes. The gyrocompassing allows the system to determine a highly accurate heading without any reliance on magnetic heading or GNSS.

The technology stems from Advanced Navigation’s artificial intelligence sensor-fusion algorithm allowing the system to extract significantly more information from the data. It is designed for control applications, with a high level of health monitoring and instability prevention to ensure stable and reliable data.

Advanced Navigation designed Boreas from the ground up for reliability and availability. The hardware and software are designed and tested to international safety standards and have been environmentally tested to MIL-STD-810. The system achieves a mean time between failure (MTBF) of more than 70,000 hours.

Additional features of the Boreas D70 include Ethernet, CAN and NMEA protocols, as well as disciplined timing via a PTP server and 1 PPS. An embedded web interface provides full access to all of the device’s internal functions and data. Internal storage allows for up to 1 year of data logging.

About DFOG Technology

DFOG is patented technology, which has been developed over 25 years involving two research institutions. DFOG was created to meet the demand for smaller and more cost-effective FOGs, while increasing reliability and accuracy.

The first generation of FOG, made available in 1976, used analog signals and analog-signal processing. The second generation was developed in 1994 and is still used to this day. It improved upon the first generation with a hybrid approach using an analog signal in the coil with digital signal processing.

In 2021, FOG evolved into DFOG. This third generation of FOG sets itself apart by being completely digital, providing higher performance and reliability while enabling a 40% reduction in SWaP-C.

To achieve this, three different yet complementary technologies have been developed to improve the capabilities of FOG.

Digital Modulation Techniques. DFOG uses a specially developed digital modulation technique passing spread spectrum signals through the coil. The new digital modulation technique introduced in DFOG technology allows in-run variable errors in the coil to be measured and removed from the measurements. This makes DFOG significantly more stable and reliable than traditional FOGs. It also allows a smaller FOG with less coil length to achieve the accuracy of one with a longer coil.

Revolutionary Optical Chip. By integrating five sensitive components into a single chip and removing all the fiber splices, the size, weight and power are reduced considerably while significantly improving reliability and performance.

Specially Designed Optical Coil. DFOG employs a specially designed closed-loop optical coil, developed to take full advantage of the digital modulation techniques. The design allows for optimum sensing of in-run variable coil errors using the new digital modulation technique. It also provides a very high level of protection for the optical components from shock and vibration.
November 3, 2022
Integrating photonic chips for better performance

KVH photonics engineers test PICs for validation prior to production. (Photo: KVH)

In June, KVH Industries launched the P-1775 inertial measurement unit (IMU), featuring its new PIC Inside photonic integrated chip (PIC) technology.

After developing and testing the technology for more than three years, the company began incorporating it into existing product lines and has shipped the first units.

The PIC technology features an integrated planar optical chip that replaces individual fiber-optic components to simplify production while maintaining or improving accuracy and performance.

The product is designed to deliver 20 times higher accuracy than less expensive micro-electromechanical systems (MEMS) IMUs. It uses modular designs for ease of integration and has outstanding repeatability unit-to-unit, according to the company.

KVH will add the technology to its inertial sensor product line for use across a broad range of applications, from navigation to stabilization and pointing.

KVH’s fiber-optic gyros (FOGs) and FOG-based products are particularly well-suited for the large and growing autonomous market, which includes applications on land, sea and air, such as drones, people movers, trucks and mining and construction equipment.

Moving Components to the Chip

Photo:With PIC technology, KVH’s FOG production process incorporates machine automation for photonics assembly. (Photo: KVH)

The controls on FOGs have an electronics portion and an optics portion. The latter consists of a light source, a detector, couplers, polarizers, a coil (which performs the sensing), and a piezoelectric device for modulating the light, explained Robert Balog, KVH’s chief technology officer.

Until now, the company had fabricated all the products for that optical circuit in its Chicago facility, in a process that was labor-intensive and required much process control. For the PIC, “We’ve taken the couplers and the polarizer sections specifically and moved them onto the chip level,” Balog said.

While KVH manufactures the chip much like any other semiconductor device, rather than passing the light through the fiber KVH is now passing it through wave guides that are contained within that photonics chip, thereby moving the creation of the coupler module into a wafer-level component.

Mass Production and Better Quality

KVH produces the chips en masse on a wafer, then singulates and samples them. Once they are qualified and spot-checked, the chips are incorporated into KVH products.
“This affords us a way to mass produce those components,” Balog said, “and gives us much better quality.”

Photo: KVH

Additionally, it produces a much smaller device than before. The company will not reveal any numbers regarding its performance improvement until it produces and distributes more PICs, but “it is already producing better results than the manually produced components.”

The production process is intimately linked to the overall performance of the sensor. “The tighter your process control, the more reliable you can make the product,” Balog said.

The new process also improves the device’s field reliability because it contains fewer discreet components. The improved performance specifications on each individual FOG improve the overall performance of the IMU or the inertial navigation system (INS) because the bias is more stable and repeatable.

The Future

What is in the technology’s future?

“The next step is integrating the light source and the detector and potentially a modulator into that chip as well,” Balog said. “So, our ultimate technology road map is to continue condensing what would have been discrete components in traditional gyros all within that chip. As this technology progresses, it will get smaller, tighter, and better. Then you will see big leaps in performance.”

August 17, 2020
KVH inertial sensor integrates photonic chip technology

New patented PIC Inside technology is designed to enhance inertial sensor performance and reliability for the growing autonomous market

Photo: KVH

KVH Industries has launched the P-1775 inertial measurement unit (IMU), featuring KVH’s new PIC Inside photonic integrated chip (PIC) technology.

KVH has been developing and testing the technology for more than three years and is now incorporating it into existing product lines. The first units have started shipping.

One of the first customers has integrated the P-1775 IMU into its next-generation rocket launch vehicle.

KVH’s PIC Inside technology features an integrated planar optical chip that replaces individual fiber-optic components to simplify production while maintaining or improving accuracy and performance.

The PIC Inside product is designed to deliver 20 times higher accuracy than less expensive MEMS inertial measurement units, uses modular designs for ease of integration, and has outstanding repeatability unit-to-unit.

“I applaud the tremendous effort by our incredible engineers in developing this groundbreaking technology and I am thrilled that we have begun to incorporate PIC Inside technology into our existing products, a process that we expect to continue throughout the year,” said Martin Kits van Heyningen, KVH CEO.

The PIC technology will be added to KVH’s inertial sensor product line for use across a broad range of applications from navigation to stabilization and pointing. KVH’s fiber-optic gyros (FOGs) and FOG-based products are particularly well-suited for the large and growing autonomous market. This market includes applications on land, sea and air, such as drones, people movers, trucks, and mining and construction equipment.

Autonomous applications rely on high-quality inertial sensors to deliver an extremely accurate navigation solution, delivering the performance required in critical metrics such as angle random walk (ARW) and bias instability.

Next-generation driverless cars, which require centimeter-level precision for safety, are the ideal application for KVH’s inertial products, KVH said. Employing the PIC design allows for a lower cost and scalable solution due to the elimination of various fiber components and a reduction of labor.

In 2019, KVH delivered its first product prototypes containing PIC technology to automotive customers and presented the science behind the technology to an audience of engineers at an inertial sensor conference, describing the extensive development, testing, and benefits of the new technology.

KVH is a leading innovator for assured navigation and autonomous accuracy using high-performance sensors and integrated inertial systems. KVH’s widely fielded TACNAV systems are in use by the U.S. Army and Marine Corps as well as many allied militaries around the world. KVH’s FOGs and FOG-based IMUs are in use today in a wide variety of applications ranging from optical, antenna and sensor stabilization systems to mobile mapping solutions and autonomous platforms and cars.

June 30, 2020