[ExI] former deceased nfl players...

[spike]

-----Original Message-----
From: extropy-chat [mailto:extropy-chat-bounces at lists.extropy.org] On Behalf
Of david
...
> 
>>... We see in nature quadruped and a few biped designs in humans and 
> birds, but as I think about it, I am very surprised evolution never 
> came up with any tripedal locomotion examples... spike 


>...Have a look at the Australian kangaroo. At low speeds it uses tripedal
locomotion with the tail acting as a third leg. At high speeds it
transitions to bipedal jumping, and the tail is used for balance and control

-David
_______________________________________________


Ja, good point.  Perhaps the bipedal dinosaurs did the same or similar.

For robot locomotion that would be a good choice for some applications.
Mammalian muscle uses energy just holding taut.  Hold any light weight at
arm's length or even just empty handed horizontal arm for just a few minutes
and notice how tired you are.  There is no force times distance, so those
muscles have done no work, but they have used a lot of chemical energy.  A
horizontal tail used for balance in a robot wouldn't use energy just holding
still.

For other applications such as office use, a triped might still be best.
There is no mechanical reason why it couldn't have three legs all nearly
identical, jointed a lot like our legs, with the two outboard limbs working
in parallel with the center one pi radians out of phase.

I need to put together a JavaScript graphic of that, or have my son do it.

spike