MOCpages : Share your LEGO® creations
LEGO models my own creation MOCpages toys shop Strong ArmRobotics
Welcome to the world's greatest LEGO fan community!
Explore cool creations, share your own, and have lots of fun together.  ~  It's all free!
Strong Arm
Strong Arm - Fully articulated - Robotic Arm built with Mindstorms by Ricardo Oliveira aka blu3-fir3
About this creation

Specifications and dimensions:

Element: 971 (arm) + 185 (control) = 1156 pieces
Axis: 5
RCX: 1x
Motor: 6x
Gear: 64
Sensor: Touch sensor 3x
Weight: +/- 1.6 kg (with RCX and some extra batteries to keep the balance)
Maximum length of arms: 43 cm
- with its back (horizontal): 52 cm
Vertical travel : 0 – 51 cm
Horizontal travel : 9 – 43 cm
Shoulder angle : 90 degrees
Elbow angle : 180 degrees
Wrist angle : 180 degrees
Wrist turning (ignore cabling) : 360 degrees
Turntable angle (ignore cabling) : 360 degrees

My lego arm has different and independent parts. It has 3 axles which movement is similar to each other: they have the same torque and the same velocity. I hope you understand these terms: the mechanism makes the axles turn once when the axle of the motors makes 240 turns! This means that we have a very slow movement but very strong; with a lot of torque.

(In case of not being used to build robots:

You can see these relationships through calculating the relation between the number of teeth of each gear. Look at the picture 0074: the first gear with 12 teeth is connected to a 40t gear; so, we have a ratio 12/40; then there is a worm gear in which, one turn makes the second connected gear turn 1 tooth. Thus, you need to turn it 24 times to make the 24t gear turn once. Finally, there is a 8t connected to a 24t gear = 8/24 = 1/3.)

I’ve built these mechanisms to the 3 axles that are responsible for the vertical travel. This allows you to turn two axles in opposite directions, making a balance with the object taken.
The shoulder seems not to have the same mechanism, but it has. The point is that I have duplicated the mechanism: 2 motors – built in opposite positions, like symmetric mechanisms.

Besides these 3 mechanisms, there are a control of the rotation of the shoulder and a control of the wrist, to split liquid, for instance.

In the pictures you see a 6AA battery box in the base. I used it to get more weight to the balance.

Manual control:

To make easier the control of the arm, I have made a joystick. This also happened because I didn’t have 2 RCX’s at that time. The joystick uses 2 pieces which control the direction of the motors ( As you can see in the picture 0127, it controls the wrist and the shoulder. When the joystick is in the standard position, the “switches” do not let the motor rotate. This is made without any lego controller; I have connected those two pieces to an AC/DC adaptor (pic. 0126). I hope you know what I mean.
You can use a second RCX to do this work and also to control the lamp placed on the hand. Instead of using those two switch pieces, you can use either rotation or touch sensors.

Feel free to ask anything you need.

Enlarge image
   Main picture :)

Enlarge image
   Shoulder Base

Enlarge image


 I like it 
  March 6, 2012
Hello friends anyone have the instructions to build it????
 I like it 
  June 6, 2011
Try making a video. That would be cool.
 I like it 
  August 22, 2010
Hey, I Really like your Strong Arm!!! It's make me think of the Bionicle attrection in Legoland. Hupie Vuurzoon
  May 15, 2010
Hey can u send me the instructions my email is
 I like it 
  September 19, 2009
very cool creation, do you have and instructions guide on how to build it, it would be really appreciated.
 I like it 
  September 5, 2009
could u please e-mail me building instructions?my email is thank you
 I like it 
  March 14, 2009
Hi Ricardo, WOW! This arm is awesome. I am a big lego mindstorms fan and I have never seen anything this cool befor. I would LOVE a set of building instructions. If you would be kined enought to do this you could email them to me. My email is Thank you so much and I hope to talk to you soon!
 I like it 
  February 24, 2009
Awesome, but how do you keep it from falling appart, are the parts glued together?
 I like it 
  February 23, 2006
Excellent!!! I really like how precise and functional the model is. Looks like you put a lot of effort into it. Looking forward to seeing your other creations.
 I like it 
  January 28, 2006
it is very cool check out my site for my robotics creations
 I like it 
  January 24, 2006
I,v never seen this part of mocs before but anyway cool arm check out my site.
 I like it 
  December 29, 2005
Very good! I've seen this on brickshelf before. I'm Pneumatic-man on brickshelf and MocPages. Please rate and review my Robotic arms, Mocs, and creations on my page too!
By Ricardo Oliveira
Add to my favorite builders

people like this. See who.

19,751 visitors
Added December 29, 2005
More from Ricardo
More across MOCpages

LEGO models my own creation MOCpages toys shop Strong ArmRobotics

You Your home page | LEGO creations | Favorite builders
Activity Activity | Comments | Creations
Explore Explore | Recent | Groups
MOCpages is an unofficial, fan-created website. LEGO® and the brick configuration are property of The LEGO Group, which does not sponsor, own, or endorse this site.
©2002-2019 Sean Kenney Design Inc | Privacy policy | Terms of use