it's not the exact science museum experience mentioned, but a quick Google search for "sand table video augment" pulled up a few, and this was the first one I found: https://share.google/89A6x4yfaw5a4hOuh

When the first Xbox were getting long in the tooth, I believe people were repurposing the motion tracking bar as the mechanism to measure the topography of the sand table. That, coupled with a video projector mounted over the top of the sand table provides the additional colors and elevation lines. (And of course a bit of cool software to process and produce the image.)