New Project Maximus

After some digging in C++ and making my Bioloid GP walk… I am here to get some inputs form all of your brains.

I am currently preparing and analyzing a new project called Max. Max will be a humanoid biped mainly focus on MX 28T or MX 28AT based actuators. I want to use Poppy kind of structure but not using 3D printing but on 5052 Aluminum based frames.

Firstly I will like to focus on legs designs. I really liked Poppy’s 6 degree bent human like design.
Can you guys suggest if I want to replicate latest poppy legs in metal bracket can I take the poppy’s CAD files and send it to some vendor for leg making? Or does it require any modification of those CADs. I am not a mechanical engineer so I need some support from community.
Can any one help me with the CADs ?

I have another option with one of my friend here
He can make me Darwin OP style legs. Should I ask him to make another frame which will be sitting on the upper knee section with a 6 degree bending? I am trying to replicate poppy kinda legs here.

So which one should I go or any idea will be highly appreciated :slight_smile:


Good to hear you want to take inspiration from Poppy for Max!

To start with, why do you prefer to use Aluminium and not 3D printed parts? The main problem with Aluminium is that it is hard and expensive to manufacture, especially if you go for a complex leg structure such as the one from Poppy Humanoid.

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Thanks jgrizou.
My aim towards Max is to walk like human first.
Secondly it should do stuffs like have eyes to detect 3D objects and may react to it, like gripping etc.

I am inspired from Kondo walking here

So am trying to know can 3D printed poppy walk like this?
I mean using the joints in 3D printing is durable?
For durability issue I was thinking for metal frames. We can discuss what is best to proceed.


Poppy cannot walk unassisted (yet!), and the Kondo walking you point to is really impressive! How this person achieve such adaptive walking is mostly unknown to us because we could not access his code or method. Moreover Poppy Humanoid is taller and has less power (relative to its size) than the Kondo which makes the task even harder.

We manufacture Poppy parts using online 3D printed services, such as or The parts are very strong and durable. It is certainly the most convenient way to build a robot with custom design.

Otherwise you can use the metal links that Robotis provides for its Dynamixel motors (e.g.



cool project that you have! I recommend that you use 3D printing. From our experience, it is strong and durable enough, especially for small robots Kondo-sized. Then, it is cheaper to make it print, and you will probably need at some point to try some variations of the leg shape. Finally, if you really want metal, it is also available in some of the 3D printing services.

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Also, what you can do is take the CAD files of Poppy and scale the leg shapes down, which should be quite straightforward with @Matthieu 's parameterisation.
You can create a fork of the leg design of the Poppy Humanoid to go into this, we encourage this a lot!

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@oudeyer Thanks for your help :slight_smile:
@Matthieu I guess for Poppy CAD files I have the right URL
Please advice is this the updated link?

@Matthieu Can you direct me to the link for any documentation of parameterisation


Hi All,
Pardon me for my nooby question here.
Actually I am trying to do some cad design for my new project in Solidworks.
I do not have budget to get all 25 MX 28T. So have decided to get only 12 MX 28T for legs.
I will like to reuse the BIOLID GP upper part that uses AX 18/12 motors. For head pan and tilt I will use MX 12W

For this I like to use Poppy software frameworks and make custom legs design.
Legs should follow 6 degree bending for that I like to take Poppy legs CAD and customize it.
Before 3D printing or CNC work I need to validate my mechanical design.
Is there any way to validate my design?

I run with a very low budget so need your comment am I good to go?
Any help will be highly appreciated.

Nop it is here:

You should use Git and fork the poppy project on GitHub. Then commit and push your changes so anyone (and us) can download and review your work.

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Thanks a lot @Matthieu :slight_smile:

After a lot of brainstorming I came to conclusion that I will do the Max vs 1.0 using AX 12/18 motors.
Vs 2 will be upgraded with poppy like leg design with MX 28 servos.

Max got some changes in design till now only challenge is I have reuse Bioloid frames :smile:
Waiting for Ordoid XU4 to come and 6 other servos in hands. I have a plan of improving torso section.

Here is how it looks now.