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Wow :D! Up so fast - that's a change :P. Remember to 5*, fav, follow and comment if you liked this, and if you haven't read the additional information, READ IT - there's something special in there!

It takes 90lbs to stall one of the motors?! That means I would only be able to stall one motor. 5*+fav

And do you have two EV3's or did you build this and took the pictures and then built half of the other robot and uploaded this project?

Nicely done! There must have been loads of torque for the board to balance a person.

Very well done! Great job using your amazing math skills to build a more mathematical robot than most of your others in terms of programming. From the video, it looks like there is a lot of compression on the pieces- but what do you expect if a whole person is standing on them? 5*+Favorite+(Already Following!)


@lil_man04 I only have one EV3. I built both builds in parallel, but since this is the simpler build, I put the motors on this one first and kept the other one as just a chassis. I then took pics of this one and dismantled it. While I was editing the pics and making the video for this, I continued work on the car :D!

@TheClutchGear The rack parts aren't compressing much - the problem is that the board bends. It bends much less if you step on it with your heels directly above the racks - this way the load is focused onto the racks rather than onto the middle of the board.

Different then what I thought it was, but better also! I really like how it measures weight. It actually could be useful (the weighing scale in our house doesn't work. Maybe I could build this instead :P). 5 stars + Fav :).

@watcherguy765 Please don't. You do remember what happened with Technobuild and the I.C.B.M. :P. Sure, this thing won't shoot holes into your walls, but if you fall through the floor (considering that you have fewer parts than me, that's pretty likely), that's most of your LEGO broken. If you must weigh yourself, use a bathtub and Archimedes' Principle :P.

Awesome balance board! BTW I'm back I couldn't be on the EV3 site because there were glitches that didn't fully log me in. It's great now.

Another stellar build. Impressive that the worm gears & motors hold up to 90lbs. Nice use of the Stock extension beams. I really want a few of the feed screws that come in that set!

When at first looking at the pictures I thought "There is no possible way that will hold a person." After watching the video I somewhat literally stand corrected! 5*+fav

Your the master bro, but I am the boxer bro ( sneak peek of my next robot )


@TheMindGarage I was just joking :P.


Whoa... This is so awesome it almost scares me! Would this break the motors? One of my large motors is already slower than the other (I break stuffz a lot :P), so I wouldn't want to try anything like this if so. I simply don't know what to say. THIS IS AWESOME! Is it possible to gear it down *so much* that a motor could hold 60 kg before it stalls?

@ninjagolloyd14 The limit isn't actually the motors - it's the gears themselves. While a single motor can hold 40kg, when testing, the 12-tooth gear and rack started slipping/grinding at about 30kg per motor.

MindGarage look at my upload if you like it please follow me so i can stay updated with your uploads, thanks bro

Five stars.

@DamonMM2000 Thanks! I thought you had left for good :O!

@TheMindGarage When are you going to publish your Nissan on the windstorms community? I saw it on YT and it was awesome

Just don't try it after you've eaten a lot.

@lil_man04 I've tried for nearly 2 weeks, but the Gallery is glitching like crazy and none of my submissions are entering moderation :/.

lol i subbed on yt ;)

Somehow before I saw the video, I knew it would hold you!

@nadajay Is that because you assume, erm, know I never lie, or you saw the ridiculous amount of reinforcement for the platform :P?




12 Favorites

This cool device is capable of weighing a person and measuring their center-of-gravity, similar to the Wii Fit Balance Board. But this one’s 100% LEGO. The board is raised by three rack sliders from the Mercedes Arocs set, driven by Large motors through worm gears. The large motors constantly move up and down - the weight on each area is measured by the difference in speed of going up and going down. The sliders have plenty of torque - I’ve calculated that it takes a weight of 40kg (90lb) to stall just ONE of the motors. As you can imagine, the board itself has to be EXTREMELY robust to withstand a person’s weight on it. The board is able to measure weight, calculate BMI (given height of user) and play simple balance games. It also has a calibration program where you place an object of known weight on the board for it to calibrate to. Be sure to check out Additional Information for more pics, info and a video, and get ready for more amazing builds :D!

EV3 balance board sport fitness weight COG center of gravity worm gear slider Arocs 42043 strong tough awesome defying the laws of physics robotolympics

Intelligent Brick Type:

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    EV3 Brick
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    NXT Brick
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    RCX Brick


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    EV3 Color
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    EV3 Infrared
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    EV3 Touch
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    NXT Light
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    NXT Sound
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    NXT Ultrasonic
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    NXT Touch
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    RCX Light
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    RCX Touch


  • 3 
    EV3 Large
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    EV3 Medium
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