MeArm - Your Robot

Cheap, Small, Open Source Servo Controlled Robot Arm

Similar projects worth following
The MeArm project aims to bring a simple Robot Arm well within the reach and budget of the average educator, student, parent or child. The design brief we set out with was to build a full robot arm kit with standard low cost screws, low cost servo motors and using less than 300 x 200mm (~A4) of acrylic.

Where the MeArm project is different is that the problem it’s trying to solve isn’t about robotics but about getting people into science, technology, engineering, arts and mathematics or STEAM. The more people who are involved with these STEAM activities the more chance we have of solving all of life’s problems, from cancer to getting humanity to Mars.

There are well over 10,000 MeArms in the wild at the time of writing, we've just fulfilled a Kickstarter for the controller, which marks the start of a new chapter, taking the MeArm to anyone who wants to learn to code!

The MeArm is an Open Sourced Robot Arm. It's small, like pocket sized and that's for a reason. It can be cut entirely from an A4 (or more accurately 300x200mm) sheet of acrylic and built with 4 cheap hobby servos. It's live on our site for about $35 or £25 for those in the UK. All the files are linked on this project page and hosted on thingiverse. It supposed to be an educational aid, or more accurately a toy. It still needs some tinkering but is at a good first draft state. There will be more instructions coming and no doubt more tweaks too.

Please get involved, build your own, break it, improve it and break it again.

  • 4 × 9g Hobby Servo Cheapest servos you can buy. Want this to be affordable and hackable
  • 1 × A4 Acrylic Sheet 3mm The aim is to cut the whole arm from an A4 sheet, with a laser cutter
  • 1 × Arduino Uno or Leonardo
  • 1 × Various M3 Fixings List to follow

  • MeArm on the Raspberry Pi

    ben.phenoptix01/26/2016 at 15:29 0 comments

    So it's been a while in coming but I finally took a look into running the MeArm on a Raspberry Pi. I've not done this before because mainly I find the Pi a Pig to work with. Really I find the set up frustrating when I could just use USB into my PC for better hardware hacking. But hey ho, lots of folks love the Raspberry Pi so I should really be looking at it a little more!

    It was actually a lot easier than I expected to get the PWM outputs working on the GPIO, thanks to some software called Servo Blaster. The Fritzing image below is actually a little more complex than it needs to be, but making it simpler would have made it look more complex...

    I've put together a WIP over on the MeArm site blog.

  • Documentation Frenzy!

    ben.phenoptix09/04/2015 at 16:11 0 comments

    Some great new docs done this week! Full guide on how build our all included kit and also a new guide on setting up a MeArm on an Arduino. All available on our resources page!

    I'll get the links updated on here too. But now onto the weekend!!

  • Another new derivative is born!

    ben.phenoptix08/30/2015 at 21:26 2 comments

    This would appear to be at least derivative number five and I'm really looking forward to the chance to go over the files of this one! The #eeArm has come to us via South Africa where it was part of a Tech Street Market project.

    Looks like there have been some savings in the acrylic, which I would have thought might have weakened the structure a little, but I'm keen to see how it performs!

    The finished article is a little funkier looking than our original. Really want to get one of these for the collection!

  • MeArms of the World!!

    ben.phenoptix08/07/2015 at 21:11 0 comments

    Putting together all the data we have to hand at MeArm Robotics we were able to cobble together this map showing the city or town where our robots have ended up. We'd like to make something to collect data on wild arms too, so if web forms to googlemaps is something you know about please get in touch!

  • Bit of a Hack Adds Polar Coordinate IK

    ben.phenoptix06/08/2015 at 08:04 1 comment

    We've had some really amazing contributions to the MeArm project and this weekend another one popped up on my twitter feed. A chap called Daniel Bailey put together a guide on running the MeArm with Inverse Kinematics (IK) - where you tell it where to go via coordinates rather than angles to point the servos at.
    It's a really great guide which covers some concepts that need addressing in the MeArm instructions, like calibration. It also has great photographs:

    It's amazing that someone has taken the time to do this work and it really makes the work we're putting in worth while! Many thanks Daniel, now everyone go and check out his site at Bit Of A Hack.

  • The MeArm makes RealSense

    ben.phenoptix02/02/2015 at 21:37 0 comments

    Points (skulls maybe) for a pun title please! Don't know if it's the black background or the sexy gold skull but I do love to write on the site. Sorry that's a pointless aside. The point is that the MeArm has been shown to work rather well with the Intel RealSense Camera, as shown by the talented Bryan Brown on his youtube channel.

    I thought this was impressive and wrote another blog about it at where I'm putting the majority of MeArm news these days. Only wish I had more time to write it all!

  • Hackaday Munich MeArm Giveaway

    Jasmine Brackett01/05/2015 at 23:04 82 comments

    Update: The winner of the MeArm Giveaway Random Draw is @Fidel salinas who mentioned @AFSLabs in their comment. We'll be in touch via private messaging to find out where to send the MeArms!

    Commiserations to everyone else who entered. Don't forget to follow or skull the #181. #MeArm - Pocket Sized Robot Arm project, or if you are really desperate for a MeArm you can buy one over at the Hackaday Store.

    Couldn't make it to Hackaday Munich? Heard about the great Robot Workshop? Well, we've got a pair of Limited Edition Hackaday Munich MeArms to giveaway to two lucky members so they can experiment at home.

    A big thanks to @ben.phenoptix for letting us hijack his project for a week, and for sending out the MeArms to the winners.

    How to enter

    All you need to do is leave a comment on this Project Log sharing this project with another member who you think would also love a MeArm.

    You do this by using our new @username and #projectid feature e.g.

    "@Adam Fabio, I've entered us into the MeArm giveaway. Check out
    #181. #MeArm - Pocket Sized Robot Arm for more details."

    Only leave one comment with mentions. You can comment more, but only your first comment with mentions will be entered in the draw. Comments without both a @username and #projectid mention will be ignored for the purpose of the draw.


    You need to leave your comment before midnight Jan 11 2015. On the Jan 12, we'll draw the winner at random, let everyone know who they are, and post the MeArms out to their new homes.

    Got questions?

    If you have any questions regarding the giveaway, you can ask them in the Project Log comments.

  • Hackaday Prize Party Munich - Special Edition MeArms!

    ben.phenoptix12/19/2014 at 17:13 1 comment

    The MeArm was lucky enough to be invited along to the Hackaday Prize Party in Munich. Since the MeArm was going to be used in the Roboto workshop we thought we'd make a little something special to honour the occasion. That was the Hackaday Prize Party Special Limited Edition MeArm!

    25 were made for the event and boy were they made for the event! All assembled in the bar the night before the event by hard pressed Hackaday staff or by myself and willing volunteers at the prize party. Being tired and emotional at the end of the MeArm build marathon it seems I forgot one thing! The spares! We'd actually produced 28 as we expected there to be a few breakages. Since they were minimum it means we actually have three Limited Edition Hackaday Prize MeArms (numbered 26/25, 27/25 and 28/25) left!

  • If I only had a brain - MeArm Kickstarter

    ben.phenoptix12/17/2014 at 21:17 0 comments

    Been a while since my last project update and so much has happened with the MeArm. I've promised some time this week to get my blog up to date now the preparations for the MeBrain Kickstarter have finished and we've launched!
    The MeBrain is an Arduino-Compatible built on the Mega32u4. We want to make it as simple as possible to use the MeArm, but also pack so much cool stuff under the hood that you can't help but want to tinker.

    The Kickstarter has gone well and reached target in just over 24 hours! We've just added some stretch goals to give us something new to aim at!

  • #meArm - Bigger, Stronger, Longer

    ben.phenoptix10/16/2014 at 10:49 2 comments

    This massive #meArm was designed and 3D printed by instructables member Jazzmyn, who it would seem is a serial hacker and maker! She purchased a Heisenberg Blue #meArm from Adafruit and learned so much from the build (her words not mine!;)) that she decided to have a go at making a bigger, stronger, longer version. I think she's been amazingly successful! She plans to add an electromagnet to the end and I would assume assemble some kind of Matchstick car crusher!

    Jazzmyn has entered the #meArm - Bigger, Stronger, Longer into a few contests so if you're over at instructables please vote for her! Or if you're on the featured team then what are you thinking?! It's a 3D printed robot arm!! Feature it stat!

    I personally want to say great job and thanks for sharing. More power to your #meArm (literally!).

View all 25 project logs

Enjoy this project?



EngineerAllen wrote 02/06/2017 at 21:48 point


took me ages to read

funny enough, when i went to download the design from thingiverse a related one looked a lot better and had a lot more downloads so i went for that one instead so i wasted my time i guess

  Are you sure? yes | no

ActualDragon wrote 02/13/2017 at 23:47 point

oh no here we go again

  Are you sure? yes | no

muthukumaran wrote 12/04/2016 at 20:53 point

I am embarking on building a larger version of meArm (at least 1.5x
to 2x the original size). Some details of by my build (very rudimentary
as at now)  are :
1. Planning to use MDF for constructiion
2. Arduino UNO with a spare 15 channel servo shield (I already have one so will put it to use)
3. Use TowerPro MG995 for shoulder, base and elbow rotations
4. Use a 6v 3A wallwart for powering motors and separate battery to power Arduino
I have a  fundamental doubt on the design though 
shoulder and elbow motors are indirectly connected by parallel links, I
was wondering what would happen to elbow motor when shoulder motor is
actuated ? In other words, would shoulder motor not  rotate the elbow motor indirectly even when elbow motor is not actuated? So, should the shoulder motor also account for the torque required for idle rotation of elbow motor shaft ?
I tried basic testing of TowerPro and it takes a fair amount of torque for idle rotation. 
Even if I proceed with this approach, would elbow motor start acting like a generator for above scenario and would that damage the motor shield / arduino ?
Thanks in advance for any suggestions and clarifications

  Are you sure? yes | no

abijithmm15 wrote 08/11/2016 at 15:32 point

i like u r project meArm,can it made to an large one.

  Are you sure? yes | no

Daniel wrote 02/29/2016 at 15:28 point

I am now doing some analysis on the MeArm, starting with the work envelope. This might be interesting for some fellow engineers! #MeArm Adventures

  Are you sure? yes | no

taylorf wrote 01/10/2015 at 02:51 point

@sgtsabot , maybe we'll both win by helping each other out. I've gone ahead and entered us! #181. #MeArm - Pocket Sized Robot Arm

  Are you sure? yes | no

Jasmine Brackett wrote 01/12/2015 at 01:17 point

Hello taylorf, it's not clear I know, but can you go post your comment on the project log

That will make it a valid entry. Thanks.

  Are you sure? yes | no

sgtsabot wrote 01/08/2015 at 02:08 point

Am I random enough to win a mearm? I think I am! The only thing cooler than robots is robots with lasers!

  Are you sure? yes | no

Jasmine Brackett wrote 01/09/2015 at 22:12 point

Hello sgtsabot, go to Read the 'How to enter' bit carefully, and leave a comment there. Then you might be in for a chance to get an arm!

  Are you sure? yes | no

Jasmine Brackett wrote 11/18/2014 at 14:31 point
Hey Ben, great to meet you at Hackaday Munich. I thought I would let you know that Stefan-Xp has shared some images from the day starting with a few of the MeArm tables :)

  Are you sure? yes | no

Alvaro wrote 11/18/2014 at 13:16 point
Ben, I've been waiting for phenoptix to ship a mearm to me for a month and a half already. i've sent you two emails already -which have gone unanswered so far, meanwhile you're blogging and tweeting and whatnot. If you set up an online shop you have to take care of it instead of playing with gadgets all day long. I'm really pissed and you have my money already and I can't do a paypal dispute since I paid with Bitcoin.

  Are you sure? yes | no

ben.phenoptix wrote 11/18/2014 at 13:39 point
Hi Alvaro, apologies that we missed your email (I can only find one though). It's been a busy period and I can but apologise and make sure the arm is sent. I'll also put a couple of metal gear servos in to try and go some little way to making up for the poor service.

  Are you sure? yes | no

Alvaro wrote 11/19/2014 at 23:38 point
Thank you

  Are you sure? yes | no

filid wrote 11/17/2014 at 07:20 point
Hi Ben,

thanks for giving me on of the arms on the hackaday in munich. I will use it as said on the next coderdojo in munich.
Here is the first glimpse of what we going to present to the kids.


  Are you sure? yes | no

Jasmine Brackett wrote 08/06/2014 at 20:19 point
Hello ben.phenoptix, time to add a few more details to your project to give it the best chance of going through to the next round of The Hackaday Prize.

By August 20th you must have the following:
- A video. It should be less than 2 minutes long describing your project. Put it on YouTube (or Youku), and add a link to it on your project page. This is done by editing your project (edit link is at the top of your project page) and adding it as an "External Link"
- At least 4 Project Logs (you've got this covered)
- A system design document
- Links to code repositories, and remember to mention any licenses or permissions needed for your project. For example, if you are using software libraries you need to document that information.

You should also highlight how your project is Connected and Open in the details and video. There is a couple of tutorial video's with more info here:

Good luck!

  Are you sure? yes | no

JayPee wrote 07/26/2014 at 19:00 point
I kind of want to build one of these as a first robot arm project, however I have 1/4" acrylic and larger servos (sg-5010). I think I'll dl your files and scale them up so my motors will fit, and I promise to keep the M3 holes the same size. I'll keep you updated/appraised/etc!

  Are you sure? yes | no

APBurner wrote 07/02/2014 at 19:11 point
Is there any way to get a printable PDF for those of us without a lasercutter of 3D printer. I could cut it out of plywood with my scrollsaw.

  Are you sure? yes | no

ben.phenoptix wrote 07/11/2014 at 10:19 point
Sorry for the delay! Great idea, adding it now!

  Are you sure? yes | no

ptkinvent wrote 06/18/2014 at 14:06 point
Pretty awesome, saw your design on as well

( )

  Are you sure? yes | no

Jasmine Brackett wrote 06/10/2014 at 19:13 point
Hello Ben, Good work with the updates and letting us know what happened at the Science Museum.

We've updated the submission process for The Hackaday Prize, so If you want to officially enter this project - login and use the 'submit to' under your project images on the left hand side.

Any problems give me a shout.

  Are you sure? yes | no

glofishing wrote 04/17/2014 at 21:28 point
By challenge I mean, what is the torque profile? It looks like the torque profile is different from robots that hook the servo directly instead of through a linkage.

With your model of production you could offer multiple SKUs without incurring much extra cost. I could see a simple robot arm with 3 motors sparking the desire to buy a larger arm.

The arm looks cool but I have an arduino, servos that came with, and access to a 3d printer. A better audience to go after would be people who do not yet have an arduino.
I could see this thing sell a lot of units on kickstarter or science toy store, coming in a flat package where you break the parts off and screw together.
I recall the barebones arduino costs something like $5 total. Tack on another $6 for servos (or hobby motors with no feedback other than current monitor to prevent burnout).
The question is, how much does the frame cost?

BTW, theres an artical on hackaday for programming barebones arduino with the audio output. So it could still be a good device for hackers.

What is your goal with this project?

  Are you sure? yes | no

ben.phenoptix wrote 04/29/2014 at 08:37 point
Thanks very much for your questions, sorry that 11 days have passed since you asked them but I've really been thinking about the project a great deal since then.

I'm not sure of the torque profile of the current MeArm but would like to find out, I've looked into measuring it but will have to look again as I'm still a little unsure of the methodology, if this is something you know about I'd be really grateful to have your input.

I could see the multiple arm model working, and have half an eye on that bringing in some larger servos and just dragging the whole model to scale it up.

As for the broader audience I've been thinking about that too. The plan is to build a bare bones Arduino compatible, either with the 328 for ease and through hole parts (that could be breadboarded) or 32u4 based to have USB connectivity without the need for another chip or external programmer. The board would have two joysticks for controlling the arm and be flashed with a basic sketch out of the box so to speak. It would be an Arduino at Heart project. The break out of a board idea was put to me a few weeks ago at an event and I like it, but broken acrylic is really sharp so that might limit that idea somewhat. Jack is making the files to test that to see.

I'll be taking the MeArm to the Science Museum in London for 5 days of workshops so will see what feedback we get there. It would be interesting to build a "retail" style product with it, but that wasn't the aim. A retail product or kickstarter would publicise the project so that would be advantageous.

The frame is cut from a single sheet of A4 size acrylic so depending on where you get your acrylic and if you have access to a laser cutter it could be as low as $1.

The goal with this project is to build a robot arm that is available at low enough cost as to be available to whoever wants one.

  Are you sure? yes | no

ben.phenoptix wrote 04/17/2014 at 18:49 point
Not sure what you mean by what's the challenge? Could you explain a little more what you mean?
You could put a kit together yourself from the plans for around $10, as long as you were savvy with your servos and had access to a laser cutter. The problem with me providing a kit at the $20 price is there would be very little profit in it once other expenses were considered. Profit is important to me because my kids have become accustomed to food and shelter.
You could remove a servo but it you'd lose so much functionality.
There wouldn't be a massive difference in price for a wood kit, although it's a cheaper material its more difficult to work, you have to spend more time cleaning the laser and if you get a batch of crappy laser ply you get a lot of wastage.

  Are you sure? yes | no

glofishing wrote 04/17/2014 at 16:39 point
What's the challenge with the design? I have never designed a robot arm in a serious manner.
This could be a cool kit if the pricing was better. Do you know the price difference between acrylic and wood? I could see myself really enjoying this if it was $15-$20 total. Even if it meant less degrees of freedom. 3 Motors would be enough for me.

  Are you sure? yes | no

ben.phenoptix wrote 04/17/2014 at 13:56 point
Right now just an Arduino Sketch to control the servos, v.basic. Up to now it's all been about getting the hardware right. I'll add it to Github anyhow!

  Are you sure? yes | no

glofishing wrote 04/17/2014 at 13:53 point
Is there software?

  Are you sure? yes | no

Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates