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Quantum
07-28-2009, 01:07 AM
Well the mini biped didnt turn out to well but the main reason I built those legs were for this guy its been an on going project for awhile and finished up the body. Never built a quad so here it goes.

I still need to make the head and tail. I will just update as things get done. Before I get started on the tail and head plan to do some code work to get this guy rocking.

Just a little more info. For the head I'd like to use some simple sensor for detection maybe a ping it will also give the appearance of eyes. And two neck servos for some simple up/down left/right movement. The tail no servo small motors on a pully system using fine steal thread so the motion will be fluid.

Battery is going to a small lithium battery for wieght issues and Ill be using a controller board based on Parallax's Prop.

Since I saw the StickyBot I have had this in the back of my mind.

Project Plans
Wieght: Currently 15oz.
Material: 6061 AL .04 and .06 thick.
Servos: HS-55 (Hitec) Running at 5V/6V thru a UBEC
Controller: Propeller Based
Battery: Lithium something that has about 10A max 800Mah.
Some Pics Below.

Zenta
07-28-2009, 01:23 AM
WoW!

It look awesome! Very well built and nice custom parts.

Did I count 6 DOF per leg!? I bet its gonna be pretty heavy, what servo are you using? Have you solved the gait/kinematics?

The relative large feets should make it able to walk pretty stable I guess.

Keep up this great work. Looking forward to see more!

-Zenta

darkback2
07-28-2009, 01:37 AM
I think I have to take a look at these micro servos. Great bot. Can't wait to see it move!

DB

Quantum
07-28-2009, 01:43 AM
Thanks Zenta

Yup 6 DOF per leg. It should have that sneaky looking walk that lizards have.

I just finished putting it together last night. It wieghts in at 15 oz. I have that mini hex which is 12.5 oz and I have put almost twice the wieght on it so I am more than confident that wieght right now is not an issue. The servo are HS-55 by Hitec. I had just enough to build what you see.

Its gait will always have 3 legs down when walking and the IK is going to kill me to figure that out. Thinking of doing a mix. Tables and IK motions.

As for the feet I made simple round ones as well so I have those at the shop I snap some pics of those aswell. The bottom of the feet will have a rubber sole which I'm cutting out right now.

I'll make a simple video showing it doing some simple standing and squatting lifting and moving the limbs around.
This should be in a day or two.

Paul

jes1510
07-28-2009, 09:54 AM
Nice! You have to keep the big floppy looking feet. It really gives it character.

gdubb2
07-28-2009, 11:53 AM
Very nicely done. I'm looking forward to seeing more. I was heading towards a lizard type build with Bheka before getting sidetracked my the mech thing.

The gait will indeed be challenging, It seems there are so very many creatures with such interesting ways of motivation.

Good job
Gary

Quantum
07-31-2009, 09:39 PM
I havnt had time this week but this weekend is the plan to get some coding done.

Quantum
09-01-2009, 11:15 PM
Sorry for no updates any sooner than this. Working on some code. Its a lot harder than I though and it dosent help to much since Im not that great at it to begin with. Its not dead but slowly chuging along.

nagmier
09-02-2009, 12:04 AM
I hear ya Q, dont feel bad we all hit that point. I happen to be in a similar crunch coding can be fun and a real pain at the same time :D

Quantum
09-02-2009, 12:26 AM
God do I hate writing code. I would rather build and have someone else code.

tom_chang79
09-02-2009, 03:30 AM
Very, very nice looking hardware you got there!!! Looks like air-borne grade stuff, very minimalist on weight but highly functional!!!

I share the same sentiments Q, I think I enjoyed doing the electronic hardware and the mechanical assembly more then I do coding. But it's very rewarding. Once you get something going, you keep building on it, each time improving something, locomotions, sensors, and etc...

6DOF per leg quad, I can't even imagine how fluid the movement will look like with a good gaiting. Have you checked out Oricom's site? Zenta mentioned it in one of the postings on another forum:

www.oricomtech.com (http://www.oricomtech.com)

They have some extensive gaiting information as well as links to researches of gaiting on there... Truly awesome gem of a website in the research of walking bots...

EDIT:
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Forgot to mention, you can start by reducing the DOF on each leg (by fixing the PWM and not moving it) and trying to get it to walk. You can then incorporate another DOF as you progress in your coding...