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Hexapods

Right and wrong ways of walking?
Six-legged animals are extremely abundant on earth: insects! With that fact in mind, you would expect that much would be known about how they walk, and that is indeed the case. There are no large six-legged animal on Earth though, and when designers or writers have to make any up for a film or illustration they seem to forget that you do not have to come up with any brand new design. as the solution is right there. The most common insect gait is the tripod, explained below, but also shown here. As you can see, it is easy: each tripod consists of a front and hind leg on one side and a middle leg on the other side.
With that in mind, you would think that people working on the film Avatar would take a good look at insects but they did not. Pity. Instead, they chose the odd solution of coupling the front and middle leg on each side to move in unison. These legs are also placed close together. In effect, the gait is then that of a quadruped, as shown in this model (here, a trot). I wrote more in a blog post on just that subject. I still think it is a pity, because there is so much more you can do with six legs, as explained below ('if only they had asked me, etc...').

tripod

wrong
wallow walk

Marshwallow walk
The marshwallow is a large swamp hexapod, whose gaits have been well-studied. There is a post on its ;a href design history on the Furaha blog http://planetfuraha.blogspot.nl/2011/12/from-ifb-archives-2-marshwalloidea.html design history on the Furaha blog As in four-legged animals, the 'walk' in six-legged animals is typified by an even spacing of footfalls over a cycle, but the difference between phases feet is of course smaller at one sixth instead of one quarter of a cycle. Again, you need to work out the phase of any leg by following the lines connecting it to the left hind leg and add all phases. The result is a stable comfortable gait, in which there are always at least four feet feet on the ground.

Marshwallow in tripod gait
Six-legged animals can also walk with their legs arranged in pairs, but where there were only three ways do to do with four legs, there are many more ways to divide six legs into three pairs. We will not show any of these here as it is not difficult to work them out. Instead, we will show that the legs can also be divided in threesomes, of which there are then two. The simplest variant is shown here: the tripod gait. It is extremely stable and fairly boring. There are always at least three feet on the ground and sometimes six; that's why it is stable.

wallow walk
wallow walk

Marshwallow in a fast run
There are various symmetrical as well as asymmetrical fast gaits for hexapods. We will show one that is suitable for a relatively slow animal such as the marshwallow. A word to the wise: do not underestimate a marshwallow and never position yourself between them and their favourite pool. Shown here is the 'ripple run', in which the middle legs move in such a way that there is little risk of bumping them into the other ones. Marshwallows can cover quite a bit of ground in this way.