Knex Robotic Bottle Flipper





Introduction: Knex Robotic Bottle Flipper

About: Hey everyone. I'm Thibault Art and my biggest hobby is to build huge machines in K'nex. I like also to draw a lot and take care of my corn snake. On this page you will find K'nex ball machines, K'nex element...

Hey everyone,

After 4 months, 7 prototypes and many fails, I finally finished one of my best knex inventions: The Knex Robotic Bottle Flipper!

So basically, a few months ago there was a very popular trend going on called "The Bottle Flip challenge". After watching several videos on YouTube about this challenge, I thought that there was maybe a way to make a robot that does a perfect bottle flip with just the push of a button. And this build was without any dought the most frustrating machine i've ever build! I tryed many things like: trying different water bottles, trying out all kinds of rubber bands, 7 different prototypes, adjusting the water level in the bottle, adjusting the speed and strength on the arm that throws the bottle, adjusting the height, and a LOT more! But it was all worth it!

The machine is 100% made out of knex: It has:

3 Cyber Knex motors.

1 Classic motor.

1 12V motor.

2 Transmissions. (1 to control all the movements and 1 to activate and shut down the robot).

2 Buttons and 4 handles to adjust the height and throwing power on the arm etc.

A tray to store the bottle.

2 Motorized arms to stabilize the robot just before the arm throws the bottle.

A main button to activate the robot.

About 5600 pieces.

And a 50 cl water bottle.

The only downpoint is that the robot is incredibly unreliable. After throwing the bottle about 10 times the arm starts to malfunction a bit. So after a while I have to adjust the water level in the bottle.

The main transmssion that controls all the movements of the robot works about 55%. But I'll try to make a second version that is atleast 80% reliable. If it works, I'll make instructions of it.

You can take a look at the video above to see the robot in action!

I want to thank everyone for taking the time to check out my creation, and if you are willing to give me your vote for the Robotics Contest of 2017, that would really make my day :D, every single vote means a lot to me!

Thanks for watching/ reading,

~Thibault Art~

ps: sorry if my English doesn't make a lot of sense, I'm working on it :).

Step 1: A Few Nice Shots:

Step 2: The Main Transmission:

Step 3: Second Transmission:

Step 4: Buttons and Handles:

Step 5: The Table:

Step 6: The Moving Car With the Throwing Arm:

Step 7: Elevating System:

Step 8: Deconstruction:



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44 Discussions

This is absolutely brilliant. The amount of moving parts and thought that must have went into this is crazy! Now, I wonder, why wasn't this featured? It definitely deserves to be. Very impressive build.

1 reply

1 year ago

This is absolutely insane. You're like the bottle flip master! Congratulations on being able to make this...must've taken you about a week to make a mechanism that worked!

6 replies

Haha, thanks a lot! Yeah, finding a mechanism that was good enough was very challenging.

yeah, I bet! btw, voted. Totally deserves it. :)

btw, congrats on the big facebook share! That's huge!

Haha thanks, never thought it would get that many views 0_0.

Yay, you put this on instructables. I might try to make a smaller, less complex version and post instructions if it is ok with you.

5 replies

Ok, this is harder than I thought it would be. I might just give it up, but could you show me a picture of the thing that holds the bottle for the flip? I can't figure out how to make it let go of the bottle at the right time.

No problem, I'll send you a picture once I rebuild the hand that holds the bottle. But of course, if you have a different bottle, you'll have to modify the design a bit.

I think the bottle that I will be using is pretty much the same as yours. BTW I have found a design that might work.