As some of you know I have been working with a new robot project. This time I'm trying to make a quad walk. I must say when I saw the [ame="http://www.youtube.com/watch?v=W1czBcnX1Ww"]Big Dog on youtube[/ame] I was VERY impressed and thinking that must be almost impossible to copy :lol: Anyway I'm not trying to say that my goal is to make a "mini Dog" or a quad that has the abilities like this big dog (its probably way way over my little head )but some of the design are inspired of the Big Dog.
One big challenge with all quads is the walking part. Its almost like having a four legged table, cut of one leg and its very unstable. And the table has not even tried to move . So I have been thinking of a leg design where you easily can shift the COG, by adding one DOF. Another challenge with some quads (2 DOF) is the turning part.
Here is a picture of the body (this is an earlier version, a bit shorter)
As you can see I'm using a 5645 servo and this is the 4. DOF. The body are made of 3mm aluminium, all parts are handmade with a bandsaw.
For powering I'm using 2x LiPo's and I'm trying to use 2 Turnigy 8Amps (maks 15 amp burst) DC-DC converter. This is a picture showing them modified with a spacer I used for mounting:
Another picture of the brackets/spacers for holding the servowires and the powerswitch:
And here they are mounted to the body. I'm gonna place the SSC32 on top of the black plastic plate.
Another view (underside):
This is a picture (also bottom view) showing the Turnigy mounted between the servos:
And finaly a complete mounted body with the SSC32 onboard. I still have some work left. Calibrating, mounting batteries and BlueSMIRF.
Legs curled up:
For the time I'm also working with the kinematics on a Excel sheet. The reason for why I'm using Excel is that its very easy to experiment with different fomulas and kinematics methods. But my goal is also here (like for the Phoenix) to have a onboard brain doing all the math.
Felix is not walking yet...
BTW: The foot are made of parts from my very first hexapod I made late 2006:
I'll post more information when I have a video ready