The researchers from UT built a system to protect against GPS spoofing. In order to prove that their protection system works, they had to demonstrate that GPS spoofing is feasible. Without exception, every news item on this only mentions the spoofing part, and not the protection part.
Military unmanned systems use encrypted GPS that is not vulnerable to the attack demonstrated.
Its possible to make a vehicle fly erratically, or even cause it to crash by spoofing GPS. But to take control requires a lot more than what was demonstrated. An error of 1us in the spoofed signal corresponds to 1000ft -- that's why the actual descriptions of the vehicle say 'banked hard' or 'veered' off course.
GPS jamming is so much easier than spoofing and results in the same thing.
Does it? Can't the drone tell that the GPS input that it's getting is inconsistent and fall back to flying home using dead reckoning?
Edit: the low-cost sensors can be augmented with sensors other than GPS too, like vision processing. This has been demonstrated but is not yet in widespread usage. I expect to see this become more common due to demonstrated vulnerabilities in GPS.
The unique value of inertial navigation is that it requires neither receiving nor sending a signal that can be jammed or spoofed, hence why the military uses it for everything.
Citation: Myself, I worked on a variety of systems including INS and GPS in the military.
LR gyros are also limited by physics to a certain limit of precision, and this is the specific mechanism by which they can drift (from what I understand though building larger gyros might help). So flying for a long time.... I don't know to what extent we know how much drift might occur. It would certainly be possible to build in some checks here though since landing in Iran instead of Afghanistan would seem to show some discrepancy between the two systems.
I am just not sure you can be sure that relative position will be as accurate as absolute position over an extended period of airtime.
I'm am pretty sure this is very wrong, although I'm not an expert enough to downvote you. Having multiple systems allows one to average out (statistically independent) drifts; it's not just a protection from failure. I don't think there's anything special about a "slow turn" which will cause military-quality INSs to have correlated drifts.
I think the real problem is that INSs are simply to bulky and heavy for drones, rather than anything to do with drift.
I heard some Russian ICBMs had a special window so that cameras can see constellations for that purpose.
Low-cost GPS jammers are $30-$50 dollars, though they are illegal to sell or to use. Jamming is a simple matter of sending out a signal more powerful than the signal received from the satellites. 100mW transmitter is more than adequate in close range.
If that drone is in a homogenous-looking area, say a desert with litte habitation, it wouldn't be hard to slowly get the drone to a different target than desired, possibly having it think another car or house is its target.
They were using a small rotary wing (relatively cheap) research UAV, despite the various articles including pictures of Global Hawks/MQ-9s etc.
These small systems are usually designed for research, and so use the same UBlox/MTK/Sirf based GPS chipsets you find in sat-nav systems for example.
It looks similar to a Yamaha RMax, although I can't be bothered to find the actual model. The RMax is designed for agricultural use & research, not fighting wars.
The vehicle control software simply assumes the GPS is correct. It wouldn't be that difficult to cross-check against the IMU data - our research drones can happily fly for a few seconds if they loose their GPS lock but spoofing would probably knock them down, because we just assume it won't happen!
You could build a DIY version of the Texas drone for around $1000 using open source hardware and a COTS model helicopter.
This not news, anyone who works with these vehicles knows this. It's like shooting a horse and then claiming terrorists can take out tanks with a single bullet.
You could as well use a replay attack against the pilot's control system (probably on 2.4GHz) using much cheaper hardware.
There is still plenty of work to do before these class of research drones become commonplace overhead - in particular, practically every onboard system is a single point of failure.
If you are comfortable would you mind linking to your homepage or sending me your contact info? (You can find my email at dylanfield.com) I'd love to talk more with you sometime.
Edit: yep. It's from Adaptive Flight, Inc. which is a modified Logo 500.
The US military has always used inertial navigation systems, usually based on extremely precise laser interferometers. You can't spoof or jam inertial guidance short of locally altering the laws of physics. A few decades ago, GPS was used to apply corrections within the (classified) error bounds of the inertial navigation system, which could be significant; any GPS correction outside the error bound of the inertial navigation system was interpreted as GPS being compromised. As the decades have passed, inertial navigation systems have become progressively more precise to the point that GPS is adding a rapidly shrinking amount of extra precision.
In fact, the US military is starting to test a new type of ultra-precise interferometer that allows inertial navigation to exceed the precision of GPS. GPS correct INS will only continue to be used to the extent it is inexpensive and gets the job done.
They are #13 on the list of world rankings of engineering schools: http://www.timeshighereducation.co.uk/world-university-ranki...
By saying "Texas college", it makes it sound like some random second or third tier school did it. That's much more sensationalistic as it can easily give the casual reader the impression that pretty much anyone can easily hack these drones. If they said a team from a top engineering school did it, it would not frighten people because that's the kind of thing you EXPECT people from top engineering schools to be able to do.
Sorry, conditioned response from this alum.
so likely the simplest answer is correct, it's not a giant conspiracy after all.
The article sets the stage for easy agreement with the idea that US drone tech needs an overhaul. Even if the first appropriations toward this go to a small subset of current military drones, that gets the ball rolling.
I bet you DHS will turn this horrible news into a good PR, something like "we noticed they could take over our drone, but you see if we get additional 10 billion in funding, we could use encryption over GPS and then all our drones will be safe again".
Note that they are able to quite precisely control the spoofed location--there is no hard banking or veering. The phone thinks it's moving smoothly at 40 MPH.
Also note that it is believed that people have already been killed by GPS jamming: http://www.newscientist.com/blogs/onepercent/2012/05/gps-los...
Each one of these could be a potential missile used against us.
edit: ( I think the real concern in this situation would be reverse engineering with an eye to finding vulnerabilities to be exploited in other drones, not so much reprogramming the one and only they have )
Is it possible to somehow sign GPS coordinates? (Perhaps sync an internal clock at each mission's start, and check a time-based signature?)
If not, are there practical challenges to integrating the output of a drone's engine and calculating the path travelled, instead of naively believing satellite coordinates?
Actually, wind must make that difficult. For a car, you can attach a magnet to each wheel and count the surges as it passes a sensor on each rotation, to give you an idea of where you are. Due to the external forces on a drone, you would probably want to measure forces with an accelerometer/gyroscope, not engine output.)
What are the challenges involved in such? Is internal-location tracking even feasible?
GPS spoofing/jamming only works for systems that use GPS navigation systems; military weapons and systems have never used GPS navigation. Inertial navigation systems are spoof-proof.
If they're not: dear DoD, I can fix this for you with about $50 worth of parts.
The black box transcript from AF 447 is quite an interesting read: http://www.popularmechanics.com/technology/aviation/crashes/...
Inertial navigation used to have larger margins of error than GPS. Since GPS was not trustworthy and inertial is, they accept GPS fine-tuning to the trusted inertial system. If the inertial system and GPS system disagree, GPS is ignored.
State-of-the-art inertial systems are now more precise than GPS.