Remote metal detection equipment?

[l_aventurier]

Hi,

As part of a bigger project, I’m investigating the different technologies available to detect metal remotely.

Let’s say there is a big wall, 50x50m and made of wood. On that wall, there are many small pieces of metal, let’s say 20x20cm each, their locations on the wall is random.

The electronic equipment is located 50 meters away from the wall and its purpose is to detect the “exact” coordinates of the pieces of metal on the wall (coordinates relative to the electronic equipment).

The pieces of metal (in red on the diagram) are visible (not hidden, nor buried) but there may be fog or lack of light so “photography + image processing” can’t be used.

From your knowledge/experience, what other approach could be used to solve that problem. What sort of equipment can do that? I know nothing to that field so I’m after some good pointers to get started .

Those components would be integrated in a bigger system so they should provide some sort of interface that can be accessed by other components driving it (to be somehow controllable programmatically from software or HDL kind of stuff).

Last comment is that we can’t mark the metal objects in any way before the experiment, no access at all, we just know they are there and are the only thing made of metal on the wall.

Thanks in advance!

 

[Sceadwian]

What is this for? The purpose of your post is vague at best and all answers to a post this complicated require intimate knowledge of the exact application in which your simple seeming question will actually be required to perform in.

If you description is accurate a simple thermal imager would work flawlessly, the emittance of metal and wood are dramatically different, even at the same temperature they will look very different to a thermal scope.

 

[l_aventurier]

Your comment about Thermal imager is exactly the kind of info I'm after. I just didn't know how to detect those pieces of metal.
Thank you!

So, I had a quick look on the internet and one thing that looks problematic is that the products offered by thermal image companies seem to be "all-in-one", camera + LCD screen + handle + ... in one item, I would much prefer to have just the camera bit with some port/interface outputting a real-time stream of data that can be used by either a PC (with a developper API) or other components (some ports following a standard protocol).
Has anyone got any experience related to those?

Also, half the problem is still there. I want to have the X,Y,Z coordinates of those pieces of metal relative to the electric equipment and those thermal imager just return a 2D chunk of data... In short, I still don't know how far the thing is.
One solution would be to somehow point at the object (once found with the thermal imager) with some sort of laser that can read the distance. Does such a thing exist? something that you can just point at an object and it tells you how far it is? If you know the location (and angles) of the pointer + the distance of the remote object, you can work out the coordinates of the remote object.
Any comment on that?

Thanks again, I appreciate this.