Invocation Norse rites where Odin is invoked to "ride" workers of seidr (Norse shamanism), much like the god rides his eight-legged horse Sleipnir. Indeed, forms of possessive invocation appear throughout the world in most mystical or ecstatic traditions, wherever devotees seek to touch upon the essence of a deity or spirit. Some have performed invocation for the purpose of controlling or extracting favors from certain spirits or deities. These invocations usually involve a commandment or threat against the entity invoked. The following is a curious example of such an invocation, found engraved in cuneiform on a statue of the Assyrian demon
Legged robot tripod. Four-legged robots also benefit from a lower center of gravity than two-legged systems. Four legged robots include: Six-legged robots, or "hexapods", are motivated by a desire for even greater stability than bipedal or quadrupedal robots. Their final designs often mimic the mechanics of insects, and their gaits may be categorized similarly. These include: Six-legged robots include: Eight-legged legged robots are inspired by spiders and other arachnids, as well as some underwater walkers. They offer by far the greatest stability, which enabled some early successes with legged robots. Eight-legged robots include: Some robots use a combination of legs and wheels.