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by hef19898 844 days ago
Sure. And then you have to upload those new, and vetted, imagines to all your drones. Other nav data is much more stable.

Mind you, military hardware is not your smartphone, OTA updates are usually not a thong for various reasons.

The approach for sure is interesting so.
3 comments
krisoft 844 days ago
That is all really interesting speculation, but I'm not describing a system which could be, but one which is already available and fielded. In cruise missiles it is called DSMAC.

Here are some papers: https://secwww.jhuapl.edu/techdigest/Content/techdigest/pdf/...

https://apps.dtic.mil/sti/tr/pdf/ADA315439.pdf

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hef19898 844 days ago
Basically inertia guidance enhanced by terrain matching. Which is great, but terrain matching as a stand-alonenis pretty useless. And it still requires good map data. Fine for a cruise missile launched from a base or ship. Becomes an operational issue for cheap throw-away drones launched from the middle of nowhere.
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Zetobal 844 days ago
Yes, that's also how it works right fucking now.
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magicalhippo 844 days ago
Well if you combine it with dead reckoning, I guess even a war torn field could be referenced against a pre-war image?

I mean, a prominent tree along a stone wall might be sufficient to be fairly sure, if you at least got some idea of the area you're in via dead reckoning.

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hef19898 844 days ago
And deadrecking is already standard in anything military anyways. For decades.

As an added data source to improve navigation accuracy, the approach sure is interesting (I am no expert in nav systems, just remotely familiar with some of them). Unless the approach was tried in real world scenarios, and developed to proper standards, we won't see it used in a milotary context so. Or civilian aerospace.

Especially since GPS is dirt cheap and works for most drone applications just fine (GPS, Galileo, Glanos doesn't matter).

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magicalhippo 844 days ago
For a loitering drone I imagine dead reckoning would cause significant drift unless corrected by external input. GPS is great when it's available but can be jammed.

I was thinking along the lines of preprocessing satellite images to extract prominent features, then using modern image processing to try to match against the observed features.

A quite underconstrained problem in general, but if you have a decent idea of where you should be due to dead reckoning, then perhaps quite doable?

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