My first robot : a quadruped with 3 DOF by leg

It just trying to walk correctly for the moment :)

Update 2 : new video of the "spider style" walk

Hi everybody my name is MoX First i want to say sorry for my english : I'm French ...(and sorry for my president too...lol)

So this is my first robot, a quadruped with 12 standard servomotors and 3 dof by leg.

I make all the part myself with aluminum plate.

For now, it's just control by my computer link to it with a RS232 connection, and a SSC32 controlling servomotor card by Lynxmotion (a real good card i think :)

Today I'm trying to control it with an Arduino car but the com with UART between the two cards is not operational for the moment :( I'm also trying to include a URM37 ultrasound sensor :)

The first step was to create a second axis for all servos.

I used some support of roller-blade ball-bearing, and I stuck it to the servo with cyanoacrylate adhesive :

Now , let's use my best enemies (which offer me a lot of blister ! ) :  Saw, file, and tech vice (lol not the same signification in French MDR)

The body :  PVC plate (dimensions 180x180mm,5mm of thickness) :

Now the legs : I am going to use the terms of "shoulder", "leg" and "scratch" for the 3 parts of the legs... (sorry I know that my english vocabulary have to increase .....)

All the aluminum parts are from an old 19" computers rack ( 2mm of thickness )

First type of servos support : for the 2 servos of the "shoulder"

I have fold the plate following the dotted line, using a tech vice :

It's very important to align correctly the axis of the servo with it's new axis (the bearing part)  and to follow this alignment with the aluminum support of servomotor. Personally it's not perfect (i wish i had a numeric CNC :) future project ?!

when you love, you don't count (French proverb)...so 3 more to make ... or you could count your blisters LOL : 600W blister by hand !! thank you Miss metal file ! ........ heuuuu if you don't understand the blister thing....just French technical joke LOL

And the result with servos , but not yet fix to them ( one of them is on the "leg")

The result with the 4 supports of "shoulders":

 

Now the support for the "leg" : more simple than the other LOL ...... but... but ...it's just a poor piece of aluminum ?? ... YES o_O

The leg:

The result with 4 legs :

Now my favorite part : the scratch:

Same idea : Saw, file, and tech vice ...and blisters !

Result :

ET VOILA !

 

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Bravo! Nice robot, I like its moves. I'm french too :)  Will keep watching your progress (mon ami). Thanks for sharing.

merci Korel :)

je suis en train de faire un dossier des différentes étapes de réalisation :) sachant que j'utilise des servos standards et du matos 100% récup ça pourais intérésser du monde :) (woua en toute modestie bien sur MDR)

 

Sounds great my friend. BTW be careful not to write in french because they stick to international english language on this site making it easier for everyone. Keep up the good work :)

that is awsome and I am trying to do this for my first bot http://www.pololu.com/docs/0J42 man where dide you get the code and did you have software or mechanic background.

Hi robomaster18

Thank for that comment ! And sorry for my english : I'm French :)

To answer your question, i get the code from nowhere :) but i make some macros with the free software of Lynxmotion (you can download it freely at http://www.lynxmotion.com/p-567-free-download-lynxterm.aspx#downloads).

I bought a Lynxmotion SSC32 card that could control 32 servomotors with 1 micro second of resolution !! And for the moment i send to it commands with my pc and a RS232 communication.

So my code is follow-up of positions.

For my background, i have the luck to have a bachelors degree in computers programming and network, and an associate degree in industrial maintenance.

But the most important is not the background but the curiosity :)

If you want photos of the evolution of the mechanic part, say it to me and give me your mail i could send to you photos of all the construction steps :)

Good luck with your robot :)

In the first video, I noticed a little slipping on the desk. Perhaps rubber feet on the ends of the legs might be a good idea?

Hi Dan M

You are totally right for the damn slipping leg :) But i already put some rubber on the ends of the legs. This is a programming trouble that is solve for now (I'm working on a new version of walk, more smooth, but i make also a biped .... so the evolution of my program is a little bit slow :)

Thank for that comment and good luck with your platform for bot experiments :)