Let me guess.looks more like a harpoon than anything else, especially with what appears to be a trailing wire
Fire harpoon across the line of advance of enemy tanks. Torpedo winches itself along the cable, stopping when it is a set distance from the harpoon. Tank snags cable and drags the torpedo onto itself. Command detonation options available to reduce wastage maybe.
The same principle as the anti-aircraft rocket but done horizontally.
As I said, just a guess though, but maybe not as silly-sounding as it would first appear.
..and never got past the concept stage because of difficulties getting the harpoon to stick in the ground vertically.