SpotMini is an evolution from BigDog, which was introduced in 2009.
Basically designed for military use and was able to carry about 330 pounds.
Then came a much smaller version Spot in 2015.
Year later was introduced SpotMini with a long neck and head.
And the newest version of SpotMini as you can see in a video has smooth and more lifelike motion with a sleeker look.
Take a look how at newest version: