Bicep for Robot InMoov

by Gael_Langevin, published

Bicep for Robot InMoov by Gael_Langevin Sep 17, 2012

Featured Thing!



Use This Project

Give a Shout Out

If you print this Thing and display it in public proudly give attribution by printing and displaying this tag.

Print Thing Tag

Thing Statistics

102781Views 32713Downloads Found in Robotics


Here is "InMoov", the robot you can print and animate. You have a 3D printer, some building skills, This project is for you!!
Don't be scared or intimidated, I started this a few months ago and didn't even know what was Arduino or a servo motor!
Start with printing the hand like I did, and go on the rest if you feel.
Well it's been a fun time creating this bicep, I have gone through quite many prints for to finally release it.
Blog with more info and instructions:
This video isn't actual, I have modified many parts since then:
The latest video:


All parts are designed to fit on a 12x12cm print bed, just like the hand.
I have printed all parts in ABS.
With 0.5mm thickness for most parts.
Also most parts have an infill of 30%.
Except "pistonanticlock", "rotwormV4" was printed at 0.4mm with a 100% infill.
"rotwormV4" is the only part printed with support.
Most parts are the same for the left and right arm.
The parts named "leftXXXX" are for the left arm, easy to figure out...
Print one of each part.
Print two of "lowarmsideV1", "higharmsideV1"
You also need 2 Hitec HS-805BB servo.
A little bit of cables.
Update 21/09/12 A step by step Instructions uploaded on the blog
Update 24/09/12 Something went wrong during uploading "pistonbaseV1", you should use "pistonbaseantiV1". Sorry for this mistake. Thanks to 1Robotmaker for the comment.
Update 07/10/12 Uploaded the covers for the bicep + a simple movement sketch for your Arduino seen in the Part8 video.
Update 31/10/12 RotwormV4 is now used for the left and right bicep. If you are building a right arm, you need to inverse the green and red wires on the potentiometer. See blog for more info.
Update 03/01/13 I have uploaded the shoulder parts.
see: http://www.thingiverse.com/thing:40040
Update 02/03/13 Modified "RotGearV2" to "RotGearV3" teeth are now a bit smaller, avoiding the risk of touching the innercasing. Also modified "RotWormV4" to "RotWormV5", I rounded up the entrance of the worm, for better printing finish. Thanks to Brian for the suggestions.
Update 07/07/14 Modified "RotGearV3" to "RotGearV4" teeth are now angled with openings within the gear to allow cables to run through. Also the external surface of cylinder is smooth finish.
Update 21/10/14 PistonAnticlock, PistonBaseAnti and HighArmSide to V2 version. Bigger section diameter for better resistance to torsion.
Still working on instructions text...

More from Robotics

view more

File Name



All Apps

Auto-magically prepare your 3D models for 3D printing. A cloud based 3D models Preparing and Healing solution for 3D Printing, MakePrintable provides features for model repairing, wall thickness...

App Info Launch App

Kiri:Moto is an integrated cloud-based slicer and tool-path generator for 3D Printing, CAM / CNC and Laser cutting. *** 3D printing mode provides model slicing and GCode output using built-in...

App Info Launch App
KiriMoto Thing App

With 3D Slash, you can edit 3d models like a stonecutter. A unique interface: as fun as a building game! The perfect tool for non-designers and children to create in 3D.

App Info Launch App


It is very great,I am very want to print and assembly it,could you please provide some Assembly manual ?

Thank you very much~

All info, files and tutorials are on www.inmoov.fr

Hi, what program did you use to design all the parts ? if you used solidworks, could you share the files here ?

I'm using Blender Open Source software, it does not export in Solidworks which is non free CAD.

thank you for replying.

I can't find a way to print PistonanticlockV2 right... any advice? I'm trying to print it with a wanhao i3, at 50 mm/s with ABS ( enclosed ), at 235 c. nozzle and 100 c. bed. 50% infill and 3 shells.

Without support it looks really bad... I'm not using my fan since it's ABS, do I need it? maybe lowering my speed to 20/30?
With support it still looks bad... but less.

do i have to print the parts with the exact same infill density

Hi, in your instructions, we try Futaba S3003 Servo with arduino code, I set ON/OFF to control 0°~180°. And it have no problem.
But when we try HS-805BB with the same arduino code, I found the servo can't stop and continued rotation in the same direction.
How I can solve this problem ? the problem maybe is arduino code or ...?
What method do you use to let the HS-805BB run correctly?
hoe much voltage and current you use

Thank you ,I like your design very much.

Comments deleted.

Hi, in your instructions, we try Futaba S3003 Servo with arduino code, I set ON/OFF to control 0°~180°. And it have no problem.
But when we try HS-805BB with the same arduino code, I found the servo can't stop and continued rotation in the same direction.
How I can solve this problem ? the problem maybe is arduino code or ...?
What method do you use to let the HS-805BB run correctly?
hoe much voltage and current you use

Thank you ,I like your design very much.

The new V2 PistonAnticlock, PistonBaseAnti and HighArmSide are awesome. The clearances between parts are much better, and they are alot sturdier.

If you're capable of it, I'd highly recommend printing out PistonAnticlock and PistonBaseAnti with a 0.1mm layer height. My first set I printed out at 0.2mm layers, and they were alot noisier during movement.

Also, I don't think these need to be printed out at 100% infill. Just to be safe, I printed them at 4 perimeters, 50% infill, and they are very sturdy.

Hi, In your instructions, you say you print with 0.5mm thickness for most parts, but 0.4mm for others. Does that mean you're switching back and forth between a 0.4mm and a 0.5mm nozzle or am I misunderstanding? Thanks.

Hi, no there is no need to change nozzle. You only need to modify the extrusion thickness settings in your slicer software.

Hi. Me Again. Doesn't matter if it already work or not , can you please , please . please email me the stl files of the chest cover and the foot. please. Email [email protected]

Hi, I should posting new parts soon. I need to keep you impatient!!

gael, are this parts same for left and right bicep? so the elbow gear will be on one side for both biceps?

Yes it goes for both arms.

so, pots extracted from biceps servos will have the same connection, not reversed, but on wormgears (rotcenter, pivcenter) - reversed, right?

Exactly. Both bicep do the same fonction they don't need to be reversed.

Awesome !! I really like your project :)

Have you seen the "Razer Hydra " it would be perfect to control robot arms and hands.... & its cheap.. only $60.00 2x hand controllers.

I created a video of myself using the Razer Hydra.. you can see the video here.


it is comes with an SDK. (open source)

Very interesting. It could be used to motion control the arms.

Fantastic Gael. A pure pleasure watching your progress.

Thanks for your support!

Hi Hairygael,Amazing job.
What software did you use ,Thanks

Hi, I'm using Blender, Netfabb, Kisslicer

Hi,now I am learning Blender,and have some problems,How to draw gear with blender, and how to assemble them? Thank you very much .

For to create gears I use a script in openscad, there might be a script for Blender but I don't know. here is the link http://www.thingiverse.com/thing:5505http://www.thingiverse.com/thi.... Once created I import it in Blender and modify it to my needs.

Public Domain Involute Parameterized Gears

Is there a cover for the back of the bicep? I have printed the covers 1,2,3 and have 5 assembled pieces which leaves an opening in the back of the bicep. Yes?

Hi bstott, you are correct the back doesn't have a cover yet. My concern was the wiring connectors, nobody is going to have the same, so I decided to leave it open for easy access, a simple resolution... The back of InMoov isn't really great at the moment , LOL


im tryine to print "armtopcover3" but having troble, i opened it up in netfabb and it has some parts in red. can you help plz.

Hi, did you work yourself through? Netfabb can fix a STL if it has some problems, what trouble did you have?

There was indeed a problem with the file, It' now fixed.

I'm just looking at purchasing a 3D printer right now. What "SIZE", Table requirement for parts like this? I'm looking at a 3D Printer from Solidoodle, which allow 6-8" parts made....Thanx.

The Solidoodle has a very low attractive price, but I'm aware of this review,
written by someone who just wanted to print InMoov, but never got to it
because the printer is just very bad. They might have changed.
All parts are designed to fit a 12x12cm print bed.

Could you tell me what servos you are using in the bicep, and where you got them? Do they have to be digital for Arduino?

Hi, I used two HS805BB, same for the shoulders. You could maybe get servos that are faster and stronger in torque, but it will be more expensive. I got them on ebay, from a german seller.

I just created a forum for questions/answers:

Any chance you can add a 3mm hole in RotwormV4 down the center I have snaped 3 of them already ( they are PLA) I think they will be stronger. Before the last one broke I had the arm moving using ROS and responding to action states

Hi Peter, I saw on your pictures that you used the "Rotparts/Bicepparts" for to create a shoulder for your Robbie robot. I first did the same, but came to realize Rotworm4 wasn't strong enough for that. That is the main reason I hadn't released the shoulder yet because I have redesigned it, making the worm gear and case much stronger. After hours of test I can say it is strong enough now. But since you have printed all those parts already I will make a Rotworm as you suggest and send it by mail to you. I would be interested to hear more about your ROS.

Hi Hairygael

Thank you for that i hope to have a video up soon.
I have a hacked ROS driver and a model for visulization at the moment i only control the arm not the hand (until I get a mega). I can control each joint using topics and i can control the arm moving from pose to pose using a action server (it waits for 1 action to be completed before moving on to the next). After I get feedback working from the arm I can start using kinematics to get objects. When its working I will release the code as open source. I will put progress reports on my blog


Part is sent by mail. ROS is very interesting, because of being open source, but it is also very abstract for a beginner. That is the reason I went for MRL because it has a GUI set. Being a newbie, I first needed to get the basics understandings about servos and Arduino but I will have a look to see if I can manage something. InMoov works pretty much the same until now through MRL if I understang correctly. I create gestures/poses independant from each other and then compile them to create a task. Actions are timed by a sleep() indent and speed which allows to complete it. MRL has sliders per servos to make a convenient manager gestures. How will you add extra feedback to the arms? I would be interested to know.

The real power of ROS is in the high end doing poses is OK for demo’s(or the hand) but what i want to do is move the hand to a X,Y,Z location and have ROS take care of the joint angles (kinematics) all you need to do is write a driver that follows the commands. My plan is to have Robbie go to the fridge and get me a beer.
As for feedback I can use the output of the potentiometer (work in progress) or double gang potentiometer or some such and accelerometers to detect motion

What do you use to control all of the servo's?

I have an Arduino Mega board, then I can write sketchs directly with the Arduino.exe, or use Myrobotlab. It seems that EZ builder is a good and easier program but you need to buy their board.

Could you post the sketch you used in video 8?

 It was a very simple pattern like I said in the video. All servos start at 0 with a delay of (2000) then they go to 180 with a delay of (2000) except the bicep that can only go to 90.
If you send me your email in a private message I will give you the sketch.

OK great thanks!! :)

Could you post a zip file of all the *.stls?

 Hi bstott,
I hope this will be going better than the Makerfaire!

 Ha, ha. Me too. But, no machines working. :-D

Could be me being stupid, but it seems like the threads of pistonanticlockv1 and pistonbasev1 are reversed they dont mesh together at all. like they go opposite directions. please help.

 Ooops, something got mixed up during uploading, I upload the correct "pistonbaseantiV1" right away. Thanks.

That's fair amazing work. Very cool project!

Very impressive!

Thank you, but don't be intimidated it isn't hard to build once you have all the parts printed.