Anti-Tank Dog Mine
The simplicity of the dog mine must have been appealing concept in 1942 when the Russian army was still hard pressed fighting to keep the German invaders in check. The basic idea was that the dog carried on it's back a wooden box or packets containing explosives strapped on with a harness. The dogs were then trained to run underneath enemy tanks and in doing so they would tip back a vertical wooden lever on their backs, which would detonate the explosives, much to the surprise of the German tank crews and the dogs.
This however, was one simple idea that did not work terribly effectively in combat. As the dogs were trained by placing food under Soviet tanks they would run to the familiar smells and sounds of any Soviet tanks in battle rather than the strange smells and sounds of the German tanks, and with hindsight, one would also expect that in battle a dog would run anywhere but towards a moving tank firing overhead, and in doing so become a menace to everyone else on the battlefield.
The German army quickly learned of the Soviet hundminen and so spread throughout the ranks information that all Russian dogs likely to be encountered were probably rabid and so should be shot on sight. As a result all dogs virtually disappeared from the Eastern Front in the ensuing few days, making the use of dog mines all the less feasible.
Dog mines did have some success, but once their dangerous drawbacks were realised they were not used after 1942. Some reports on the Soviet Army after 1945 still contained references to dog mines however, and there were also reports of dog mines as having been used by the Viet Minh (fighting in Indo-China) in the late 1940s.