I have seen a few posts asking for an SES based quadruoed in the dog format. I built up a leg and grabbed a few jpg’s of it. It uses a new bracket originally designed for the hexapod chassis. You only need a simple top and bottom panel to build it all up. Feedback…
Nice little 3DOF leg. I’d use a longer C bracket (or something else) to increase the length of the thigh. It’s too short I think.
Of course this type of leg would be cooler with a 2DOF ankle on the end. 8)
That looks about right. I’m thinking maybe a more “chunky” tibia. Something like a C bracket with a square rubber foot attached as in the pix below of Chien. But that’s not bad. I’d like to play with a set of 'em!
“joueur” (“Playful” ?):
http://www.marconettengineering.com/joueur.jpg
Alan KM6VV
Yeah, It’s really nice, but I think it could use an actual foot. 
Are you planning on selling these when finished? I would really like some of them!
Who are you talking to? If it’s me, the legs were built with off the shelf components. If you’re referring to the image just above it’s not a kit but just something a guy in France built.
No, I’m talking about the legs you built.
Wow, SES with another amazing design lol
wowy, it takes a total of 6 SES brakcets, 1 tube hub, a tue, and a tube foot, it would take 5 minutes…if that, to put ur own kit together for 2 pairs of these
two cents… the biggest limitation I see to this leg approach is it has the same style attachment as hex legs, that is it sticks out the sides of the body rather than coming from below the sides. This tends to make a quad looking more like a komodo dragon type lizard sans tail than something resembling a dog or cat. if you want to develop any sort of dynamic gait the balance will be much harder to maintain because the legs are further from the center of gravity without the luxury of an instep like bipeds have. 
If thats the case then why do they sell those Hexapod legs?
Probably because its a more popular design and its implemented more then this would be.
Plus this is just a little design that Jim came up with to show what could be done, not necessarily a new leg that could be used for the hex
You’re right up to a point. I believe the new bracket (plate?) the LM has allows the “hip” servo to be at right angles to the side of the 'bot, and thus move the leg in the sagittal plane (parallel to the body), rather then splayed out as an insect, or your dragon. True, the legs aren’t under the 'bot, but they are in a sagittal plane, as are the legs of dogs, cats, etc.
Perhaps you could elaborate on effect of the “instep” a little. 4DOF?
The CG is certainly more of a problem due to the unstable nature of the gait. That’s where the additional joint I mentioned to allow the body to be shifted side to side would be a help (ARAMAS).
Alan KM6VV
There would be no point for Jim to sell these as a kit. The whole point of SES is to buy the brackets seperately with your parts list and build whatever you want. The SES can make thousands of different things, but that dosen’t mean they all have to be kits. From Jim’s point this is something he did to demonstrate what can be done, not to spur up excitement in a new Kit hes coming out with.
The biped has a flat plate for the foot so there is a moment arm from the center of the plate to the instep of the foot that allows torque to be placed along the instep. Most of the hex and quad legs have a point contact for the foot so there is no instep. a quad like the above pic has no way to shift its CoG even close to the floor contact point while a biped only needs to shift the weight somewhat beyond the instep edge of a foot.
by placing the shoulder joint under but along the edge of the torso you move a lot of the CoG closer to the floor contact point and if you have even a small foot it would be much easier to control balance, even if it were simple a spring loaded 2-axis gimbal.
Did I muddle that up enough? 
I wonder if an inexpensive joystick could be disassembled and converted such that the leg attaches to the handle and the block supporting the gimbal could be the “foot”… have to find the right joystick I suppose.
I take your point. But we don’t want outrageous feet (like Loki) on a dog or cat 'bot!
A small joystick you say? I have one in mind, but I don’t see how that helps. Might be good for sensing the ground, 'tho.
Would a gimbaled joint give leverage? Is that it?
Nah, good Good description of the COG shift! I haven’t seen videos of either; but I think Aibo and Chien DO have at least a limited capability to shift their COG. The 2nd servo can move the foot into and away from the body, and hence the COG would shift. Enough? I couldn’t say.
ARAMAS that I mentioned has a specific servo arranged with it’s axis fore-aft to further allow this shift. But I understand they’re not even using it yet!
Alan KM6VV
a joystick was just an example of a spring centered two-axis gimbal. something like this
http://www.feteriscomponents.nl/graphics/tbg-30jb2.jpg
where the body of the joystick, specifically the surface opposite where the stick protrudes, serves as the “foot” and the stick is the attachment point.
similar concept, you could use a universal joint between the lower leg and a foot surface instead but then how do you center it with springs in a rugged and reliable way.
Try this little one:
search.digikey.com/scripts/DkSearch/dksus.dll?Detail?name=252A103B60NA-ND
OK, one could machine up a ball joint easily enough.
Alan KM6VV
