Robot magazine can help a little here. Their website has a neat video of a 4 servo humanoid made out of the Bioloid kit (it’s huge though).
Also last issue had an article by Matt Bauer in which he described how he put two LiPO’s that provided regulated power to his servos, in his Robonova’s feet.
I’m wondering though how much you’re going to learn with just 4 DOF. You’ll only be able to tilt the ankles sideways but not forwards. I would think that you could learn a whole bunch more info that would be directly transferrable to your larger humanoid by having at least 2 DOF in each ankle; sideways and fwd and back.
Good point.
The nice part is, switching that around necessitates the interchange of only four brackets.
So, for an extra $20, I suppose I’ll just get them ahead of time and have multiple options.
To be honest, I had been thinking of changing my biped to the above sort of setup, as it seemed to be a lot more effective when I was playing around with the Biped Scout.
I’ve been lax and haven’t renewed my subscription to Servo.
:X
Thanks for reminding me!
I’ve had a ball with the BRAT. It’s really amazing what can be done with just 6 DOF. I think a natural progression would be to add 2 more DOF to see what can be done then. I think it would open up another completely different set of possibilities. Actually, I’d guess that the 8 DOF configuration would provide the best platform for your foot sensor experiments. Then again, simpler still would be a hip servo and 2 ankle servos and may work just as well for your project. Hmmmm…
I’ve no doubt that I’ll eventually learn more from the full humanoid about balancing than I can ever learn with this little bugger.
But, the sheer volume and variety of what I’d need to understand is a bit daunting.
This little guy should get me kickstarted in the right direction.
Worst comes to worst, it doesn’t.
In that case, I’ll just have to part this poor bugger out and have two extra pan and tilts.
Yeah, start with a BRAT. Then add more DOF’s as you work. Think of all the other BRAT builders who will be praising your name Nick. hehehe
The switch / foot PC board is a good idea. I want to have a PC board made with the switches and even LEDs, that can either replace the aluminum foot for lightweight bots, or be added to the aluminum foot for heavier bots. It’s on the drawing board anyway.
I’ve been thinking about this quite a bit and I think it’s the way to go for me to start looking at balance in humanoids. The configuration that seems to make the most sense to me is to add another servo just above the foot with the same SES components that are on the similarly placed servo on the BRAT. This would require an ABS-04, ABS-06 and ABS-09. Jim, what do you think? I remember you suggesting that adding another DOF at the hip may make more sense.
Any thoughts from other BRAT owners or SES experts?
This looks really interesting too. Any chance that it’s moved off the drawing board yet?