DPRG mailing list archives: DPRG: Robotics Contest

Thu Feb 20 09:37:33 CST 1997

> 
> James Vroman is planning to bring a functional BOT to the March 22nd
> meeting. I plan on having something ready for the trial run if anything
> goes according to plan (yeah . . right.) My entry will be a biped built
> from scratch using whatever materials and parts I can scrounge up. The
> brains will be an HC11 (or two or three) using The BOTBOARD2 from Marvin
> Green (bare-boards $15 each when you buy three). I am also using HITEC
> HS-422 servos (no DC motors or Hbridges).
> 
> I will not gaurantee that my BOT will even be able to stand on it's own
> two feet, but I plan on being able to run the course!

I've been thinking about doing a biped too... However, my money supply
is too limited to purchase the 8 servos I was needing to do my design.
How many servos are you talking?

I was thinking each leg would have 4 servos:

        _______
           O  2 hip servos  (left/right & forward backward)
	  \  \
           \  \
             O    1 knee servo (to swing the leg out forward)
           /  /
          /  /
           O   1 ankle servo  (for leveling foot before putting foot down)
         /   \___
         |_______\

One problem I thought of, was then when the power was removed, it's gonna
collapase so I'd have to have some sort of shutdown mode to put it in
a collapsed (squating) position before turning it off.  And when power is
restored, it's got to stand upright.

I don't have the money right now, though.

---------------------------------------------------------------------------
Jim Brown                jbrown at spdmail.spd.dsccc.com or jbrown at why.net
                         http://users.why.net/jbrown  
                         http://www.dprg.org (Next meeting Mar 22nd)

Work:  972-519-2868      My employer won't claim these opinions.    
Home:  972-495-3821      So I'm giving them away for free.   