Let's Make Robots!

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 :



Comment viewing options

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

Thanks for my English, and unfortunately I'm also thinking that M Bush was very close to create an other middle age ;)


Indeed. After all, we thought George Bush was bad, but now we have Barack Obama...  Talk about going from the frying pan to the fire!

I think I saw that our national debt (money borrowed that we have to pay back) is about 14.7 Trillion dollars (currently, that is about euros.) --more than double under this president than the last one. --Some say it is "only" 12 trillion, but when it is so high, who quibbles about such small differences? Money may not be our only problem, but it is certainly one of the big ones.

Hi Dan

I've got a cool solution : Let us all come together and let us create a Barack humanoid with a maths and countability program and let us put it into the white house :) a good idea isn't it ?

Good luck with your president ;)



Hi everybody :)

This is an evolution of the "spider-style" walk of my quadruped.

I'm pretty proud of this one : servos consumes more but with the weight of the NiMH accumulator,it's acceptable and I think i could have 1 hour of autonomy ...(theoretically). It's also more stable that the first "spider-style" walk (the first video).

There is always a little trouble with the last step (but I'm on it).... :)


PS : A special sign for LordGG : more alive, aggressive or suspicious ..... give me your opinion dude ;)

Have fun everybody


Great compromise :) It keeps a wild behaviour, and if you've succeeded in reducing the energy consumption to an accetpable level it is perfect !

Je reste dans les parages pour voir la suite ;)

Thanks dude ! :)

Huve fun


After comparing them, I think the new walk looks more stable, the way you shift the body's center of gravity as the robot steps.

In the third video, I noticed when the robot appeared to lose its balance and tip, so the change is a good thing.

You are totally right about the stability!

But there is always some work to improve the walk !

This version consume less current same if i putted 5 accumulator NiMH for the weight :)

But at the first step there is alway a bad skid that i couldn't delete .... I'm on it right now :)

have fun with your robot !


Hi everybody !

I post a new video of my quadruped , and as you could see, it's a new kind of walk.

I changed the position of the body and legs because after some tests with 5 accumulators NiMH (for the weight), the consuming of the servos was to high... (poor standards servos) and also because after 300 different attempts to improve the first kind of walk, i was curious to look at an other direction ....

Let me know what kind of walk you prefer :) (if you have to time ;)

Have fun with your robots !



Thanks for posting all this stuff ! When I see your robot, I can't wait to work on a walker ;) (but many things to finish first...).

To answer your question about the new walk, I must admit that I prefer the first one. It makes the robot less mechanical, more alive, agressive or suspecious, I don't know how to define it exatly... maybe the new walk just looks more predictible (because it is simpler... grrr god damned accumulators ! ;)

Keep up the good work :)