cancel
Showing results for 
Search instead for 
Did you mean: 

DARPA’s Micro-PNT sensor technology as positioning tracker?

Harley
Level 2
Micro-PNT (Micro-Technology for Positioning, Navigation and Timing) does absolute position tracking on a single chip!

To oversimplify it; Micro-PNT adds integrates a highly-accurate master timing clock integrated into a IMU (Inertial Measurement Unit) chip, making it a "TIMU" ("Timing & Inertial Measurement Unit") chip.

So these TIMU chips for Micro-PNT have integrated 3-axis gyroscope, 3-axis accelerometer, and 3-axis magnetometer, and together with the integrated highly-accurate master timing clock it simultaneous measure the motion tracked and combines that with timing from the synchronized clock, and with sensor fusion it makes a single chip that does absolute position tracking, all without external transmitters/transceivers.

http://www.darpa.mil/NewsEvents/Releases/2013/04/10.aspx

Is this technology just too expensive or not yet released by DARPA for use in non-militarized commercial products?

DARPA researchers at the University of Michigan have made significant progress with a timing & inertial measurement unit (TIMU) that contains everything needed to aid navigation when GPS is temporarily unavailable.

The single chip TIMU prototype contains a six axis IMU (three gyroscopes and three accelerometers) and integrates a highly-accurate master clock into a single miniature system, smaller than the size of a penny. This chip integrates breakthrough devices (clocks, gyroscopes and accelerometers), materials and designs from DARPA’s Micro-Technology for Positioning, Navigation and Timing (Micro-PNT) program.

Three pieces of information are needed to navigate between known points ‘A’ and ‘B’ with precision: orientation, acceleration and time. This new chip integrates state-of-the-art devices that can measure all three simultaneously. This elegant design is accomplished through new fabrication processes in high-quality materials for multi-layered, packaged inertial sensors and a timing unit, all in a tiny 10 cubic millimeter package. Each of the six microfabricated layers of the TIMU is only 50 microns thick, approximately the thickness of a human hair. Each layer has a different function, akin to floors in a building.

“Both the structural layer of the sensors and the integrated package are made of silica,” said Andrei Shkel, DARPA program manager. “The hardness and the high-performance material properties of silica make it the material of choice for integrating all of these devices into a miniature package. The resulting TIMU is small enough and should be robust enough for applications (when GPS is unavailable or limited for a short period of time) such as personnel tracking, handheld navigation, small diameter munitions and small airborne platforms.”

The goal of the Micro-Technology for Positioning, Navigation and Timing (Micro-PNT) program is to develop technology for self-contained, chip-scale inertial navigation and precision guidance. Other recent breakthroughs from Micro-PNT include new microfabrication methods and materials for inertial sensors.


http://www.darpa.mil/Our_Work/MTO/Programs/Micro-Technology_for_Positioning,_Navigation_and_Timing_%...



Micro-Technology for Positioning, Navigation and Timing (Micro-PNT)

For decades, Global Positioning System (GPS) technology has been incorporated into munitions to meet rigid requirements for guidance and navigation. As a result, a substantial number of DoD weapons systems are dependent on GPS data to provide accurate position, direction of motion, and time information while in flight. This dependency creates a critical vulnerability for many U.S. munitions systems in engagements where the intended targets are either equipped with high-power jammers or the GPS constellation is compromised.

The goal of the Micro-Technology for Positioning, Navigation and Timing (Micro-PNT) program is to develop technology for self-contained, chip-scale inertial navigation and precision guidance. Size, weight, and power are key concerns in the overall system design of guided munitions. Breakthroughs in microfabrication techniques may allow for the development of a single package containing all the necessary devices (clocks, accelerometers, gyroscopes and calibration stages) incorporated into a small (8 mm3) and low-power (1 W) timing and inertial measurement unit. On-chip calibration should allow for constant internal error correction to reduce drift and thereby enable more accurate devices. Trending away from ultra-low drift sensors to a self-calibration approach will allow revolutionary breakthroughs in technology for positioning, navigation, and timing.

In January 2010, DARPA launched a coordinated effort focused on the development of microtechnology specifically addressing the challenges associated with miniaturization of high-precision clocks and inertial instruments. The program, Micro-PNT is comprised of four thrust areas: Clocks, Inertial Sensors, Microscale Integration, and Test & Evaluation. Each of these thrust areas is made up of various efforts exploring new fabrication techniques, deep integration, and on-chip self-calibration, all hand-in-hand with the development of “plug-and-test” architectures.

The developments consider a number of operational scenarios, ranging from dismounted-soldier navigation to navigation, guidance, and control (NG&C) of Unmanned Air Vehicles (UAVs), Unmanned Underwater Vehicles (UUVs), and guided missiles. The new Micro-PNT initiatives seek to increase the dynamic range of inertial sensors, reduce the long-term drift in clocks and inertial sensors, develop ultra-small chips providing position, orientation, and time information, and provide a universal and flexible platform for the test and evaluation of components developed within the comprehensive Micro-PNT program.


http://www.darpa.mil/NewsEvents/Releases/2012/09/20.aspx

Microfabrication methods to help navigate a day without GPS

New techniques developed for smaller inertial sensors

Military missions of all types need extremely accurate navigation techniques to keep people and equipment on target. That is why the Military relies on GPS or, when GPS is unavailable, precise sensors for navigation. These sensors, such as gyroscopes that measure orientation, are bulky and expensive to fabricate. For example, a single gyroscope designed as an inertial sensor accurate enough for a precision missile can take up to 1 month to be hand assembled and cost up to $1 million. DARPA has made progress in developing less expensive fabrication methods for inertial sensors and is making them orders of magnitude smaller and less expensive.

DARPA is developing new fabrication techniques for microscale inertial sensors with the goal of creating enough accuracy to replace the large, expensive gyroscopes used today. This work is being done under the Microscale Rate Integrating Gyroscope (MRIG) effort of the Micro-Technology for Positioning, Navigation and Timing (Micro-PNT) program. During the recently completed first phase, MRIG focused on 3-D microfabrication methods using nontraditional materials, such as bulk metallic glasses, diamond and ultra-low expansion glass. Small 3-D structures such as toroids, hemispheres and wineglass-shaped structures were successfully fabricated, shifting away from the 2-D paradigm of current state-of-the-art microgyroscopes.

These microscale inertial sensors work like Foucault pendulums commonly found in museums. The swinging direction of the pendulum slowly changes as the Earth rotates. Instead of a swinging pendulum, microscale inertial sensors send out vibrations across the surface of a 3-D structure. The precession of the standing wave is measured and any changes reflect a change in orientation. Among the several new fabrication methods created by DARPA to work with these microscale inertial sensors are:


University of Michigan Image

Glass-blowing. Researchers developed fabrication methods that replicate traditional glass-blowing techniques at the microscale. The result is tiny 3-D wineglass-shaped inertial sensors. These sensors are symmetrical enough to have a frequency split approaching 10 hertz—a result never before achieved at this size and approaching levels of symmetry required for high-quality navigation devices.The frequency split is a measure to predict the symmetry—and thus accuracy—of the device. It is a measure of the difference between two different axes of elasticity. The greater the difference, the more imperfection is present, resulting in a less accurate sensor.


Georgia Tech Image

Blown quartz. Similar to glass blowing, quartz blowing can be used to make an even more symmetric structure. Researchers developed fabrication techniques needed to heat quartz to 1,700 degrees Celsius (a typical softening point for glass is about 800 degrees Celsius) and to then cool it rapidly. The fabrication can be performed in large quantity batches, producing hundreds of devices on a single wafer.


University of California, Irvine Image Image

Atomic layering of diamond. Layering diamond over a blown structure or depositing CVD diamond in a micro-well on the substrate have been shown to be effective, promising methods for creating highly symmetric, accurate 3-D inertial-sensor structures.

“These new fabrication methods were thought to be unrealistic just a few years ago,” said Andrei Shkel, the DARPA program manager. “The first phase of MRIG has proven these new fabrication techniques and begun the process of validating the new structures and materials through testing. Phase 2 has kicked off, in which DARPA seeks to hone these methods to create and demonstrate operational devices.”

Phase 2 performers seek to make these devices even more accurate and reliable by reducing frequency split from 10 Hz to 5 Hz, increasing decay times from 10 seconds to 100 seconds, and decreasing volume from 20 mm3 to 10 mm3. The final goal of Phase 2 is to demonstrate a working, first-of-its-kind microrate integrating gyroscope.

“As work continues, DARPA hopes these new technologies will enable large-scale production of navigation-grade microscale inertial sensors,” added Shkel. “Production of 3-D inertial sensors with these new techniques would cost about the same as today’s integrated circuit, making them orders of magnitude smaller, cheaper and more capable than current microgyroscopes.”


http://www.darpa.mil/Our_Work/MTO/Programs/Micro-Technology_Positioning,_Navigation_and_Timing_%28Mi...

Micro-PNT - Clocks

CSAC

The Chip-Scale Atomic Clock (CSAC) effort created ultra-miniaturized, low-power, atomic time and frequency reference units. The development of CSAC enabled ultra-miniaturized and ultra low power time and frequency references for high-security Ultra High Frequency (UHF) communication and jam-resistant GPS receivers. The use of these ultra-miniature time reference units can greatly improve the mobility and robustness of any military systems and platforms with sophisticated UHF communication and/or navigation requirements.

This effort resulted in commercially available CSAC technology. The CSAC effort achieved a 100 times size reduction (from the size of a microwave oven to a sugar cube) while consuming 10 times less power than traditional atomic clocks. An effort is currently underway to test CSACs in space for small satellite applications. The CSACs will be inserted into bowling-ball sized Synchronized Position, Hold, Engage and Reorient Experimental Satellites (SPHERES) on the International Space Station (ISS) and tested against the traditional atomic clock onboard the ISS.

IMPACT

The Integrated Micro Primary Atomic Clock Technology (IMPACT) effort is developing technologies to miniaturize primary atomic clocks while reducing power and maintaining primary clock accuracy and stability. If successful, the IMPACT effort would exceed the accuracy and stability of CSAC by two orders of magnitude. However, much of the technology that is envisioned to enable the success of IMPACT will be directly leveraging science and technology developed through the CSAC effort. Used in tandem, solid-state and IMPACT devices could serve to give accuracy and stability, while consuming low power, for both short-term and long-term mission applications.

The IMPACT program is in its second of three planned phases. Phase II requires performers to deliver a 20 cc, 250 mW working clock that will have less than 160 ns time loss after 1month.
4 REPLIES 4

Anonymous
Not applicable
Very cool but very much research work at the moment from reading the last press release. As you suggest military research and budgets can stand much higher piece prices than commercial items and the manufacturing process sounds complex which usually means expensive

I'd be surprised if we see anything being produced in cheap mass volume in the next few years.

zalo
Level 3
It looks like these systems are designed for use when GPS signals are non-existent. So really, it just has to be accurate between the time the GPS signal is lost, and the GPS signal is regained.

IMUs will never be accurate or absolute indefinitely.

DwanaKloss
Level 2
I ever meet such problem before, after the high recommendation of one of my good friends, I got a wireless cell phone signal booster, everything is OK now. You can have a try!

MrMonkeybat
Level 3
Its similar to the sensors used on PrioVR devices. Could make PrioVR type tracking more accurate but probably still need DK2's optical head tracking.

A 2 meter absolute position drift would not matter for an artillery shell but it would for VR.