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Vaccum-chamber quantum sensor device could allow GPS-free navigation

breakingdefense.com

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Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#31

Post by soneil »

jonplackett wrote: post #10
Snoozus wrote: post #9

Earlier quoted context omitted.

Just like dead reckoning works today, you start from a known point at known attitude and integrate up accelerations and rotations to keep an up to date position. Whenever you can get a GPS signal you use that to reduce the drift. Cheap systems can do this for seconds, 10k$ buys you 15minutes (MEMS), 100k an hour (laser gyro), everything above is under export restrictions and NDAs so noone will tell you what the state…

The whole premise that this might be something in everyday use one day seems completely flawed. Even at the 1cm cube of physics it’s huge compared to GPS and it uses incredibly expensive materials. If you’re a nuclear submarine or stealth bomber it makes loads of sense. For anything else I don’t really get the point.

There's a fairly obvious application in pretty much any military theatre. GPS is vulnerable to spoofing, having a second source of truth lets you know you're even being attacked. Comparing an IDS to a GPS at least gives you a canary.

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#32

Post by dumdumdumdum »

> Using a starting point as a fixed reference and calibrated to the patterns of Earth’s magnetic field, data from a quantum navigation system will give us all the information we need to accurately determine where we are.

Why is the Earth's magnetic field important? And isn't that just as easy to "spoof" (if not more) than a GPS signal?

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#33

Post by bitwize »

snerbles wrote: post #21
errcorrectcode wrote: post #16

How is this an improvement over other INS like LRG? INS mechanisms suffer from the same problem: that they only detect linear or rotational acceleration. To reach position, double integration must be performed, which rapidly accumulates error (drift) because velocity and position both have to be maintained to calculate the next position. Disclaimer: Trimble Nav alum

While I heard that the effect of double integration is bad, attempting it as a student with consumer MEMS devices was quite dramatic. Really underscores the importance of Kalman filters and updates from sensors with fewer derivatives.

You mean like... GPS?

I used to work on AUVs with inertial navigation, and a Kalman filter accepting input from GPS at the surface and a DVL or similar underwater, as well as the inertial unit, was pretty much standard equipment. The device in the article has to have miraculously low error in order to eliminate the need for GPS.

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#34

Post by danielheath »

dumdumdumdum wrote: post #32

> Using a starting point as a fixed reference and calibrated to the patterns of Earth’s magnetic field, data from a quantum navigation system will give us all the information we need to accurately determine where we are. Why is the Earth's magnetic field important? And isn't that just as easy to "spoof" (if not more) than a GPS signal?

Magnetic field strength falls off rapidly - a spoofer would be extremely large and heavy to reach even a very short range. It’s not going to work against aircraft.

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#36

Post by Animats »

DARPA has been funding work on better gyros and accelerometers for about 10 years now. MEMS gyros keep getting better. The good ones are down to a few degrees per hour.[1] That IMU/GPS is $3,386.09. Not down to the phone/vacuum cleaner price point yet.

This is nowhere near as good as the device described in the parent article, but it's good enough for a lot of applications. If you can get a GPS fix every few minutes, it's good enough for many nav applications.

(When we did a DARPA Grand Challenge vehicle in 2005, we had a MEMS gyro with over 10 deg/minute drift. That was too much for the mapping to work properly. We needed [1] https://www.mouser.com/ProductDetail/Parker-LORD/3DMGQ7

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#38

Post by willis936 »

Animats wrote: post #36

DARPA has been funding work on better gyros and accelerometers for about 10 years now. MEMS gyros keep getting better. The good ones are down to a few degrees per hour.[1] That IMU/GPS is $3,386.09. Not down to the phone/vacuum cleaner price point yet. This is nowhere near as good as the device described in the parent article, but it's good enough for a lot of applications. If you can get a GPS fix every few minutes,…

GPS is trivial to jam. Any exotic IMU has huge defense implications. Being able to miniaturize it would be a big deal.

Re: Vaccum-chamber quantum sensor device could allow GPS-free navigation

#40

Post by rjeli »

errcorrectcode wrote: post #16

How is this an improvement over other INS like LRG? INS mechanisms suffer from the same problem: that they only detect linear or rotational acceleration. To reach position, double integration must be performed, which rapidly accumulates error (drift) because velocity and position both have to be maintained to calculate the next position. Disclaimer: Trimble Nav alum

even worse, your (single) integrated gyro estimate must then be fed back into your double integrated accel filter to subtract gravity and further compound errors :)
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