Let's Make Robots!


Plays Tic tac toe
TicTacToe_v1_4.zip4.19 KB
TicTacToe_v1_42.zip4.21 KB

Introducing Strike'm,a robot that simply Strikes you out.

So,this is the Tic tac toe robot I have built. Actually inspired from Oddbots challenge,I have made this .

I decided to keep it original. From my point of view ORIGINALITY has two aspects,

1. The game should be kept original, i.e. you have to use a pen and paper,play it,win it or lose it.

2. The robot should be original. i.e. It must not be a copied stuff from some one.

Strike'm satifies both aspects,I think.

So,now here's some pics. This time I have used some ply-wood along with cardboard.


This was not my initial plan of robot,initially I was going to build something like this


But there was some design malfunction,so I switched to new idea.

I had drilled holes earlier in the board,cause I had some other plans too,but later rejected them....

The board had a lot of makes and remakes...there's a lot of signs of that

Later I thought that I can use a series of resistors on analog pin,and use it as a voltage divider. So,this was my initial setup..

all of the above were 100K resistors....

But I had problems with the readings,so changed the 100K's to 2K's and made the tin plates thinner...

covered the setup with a thin cardboard. Note those wood sticks,they prevent all the switches being pressed at the same time..

still HAD problems with analog readings,tried caps,didn't work. Then added a pull down resistor (10K) from input pin to ground and wrote a code to compensate for the bad switches.

I have never used a stepper,and I even don't have one right for the job. So,used the Servos to make it move,one servo for each axis,they are Hitec HS 311. Pretty good Servos !!!

Next was the gripper and the touch sensor. Sensor is made from IC 555. Gives pretty good response. I used cholcolate wrappers to wrap the markers and the gripper,as you can see...

Finally tested some code,glued here and there,and it was running perfectly. Sometimes,it's writing is not so accurate as The channels are damaged. they were laying aside waiting to be discarded....also the not-so-high precision wood sticks that hold the axis account for this (they are not exactly of equal length).

circuitary containing the 555 ccircuit and others...



That's all.

My special Thanks to:

1. Rick100 (http://letsmakerobots.com/user/15506),he's the one who informed me of the challenge in the first place. Thanks a lot  Rick100

2. Oddbot (http://letsmakerobots.com/user/1533) for creating such a nice challenge and inspiring others.

3. R2-D2 (http://letsmakerobots.com/user/15990) for informing me about the local shop from where I bought the Servos. Thanks.

4. Birdmun(http://letsmakerobots.com/user/14021),

   Maxhirez(http://letsmakerobots.com/user/17498) they have been always there when I jumped in the shoutbox.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

The robot works and IT LOOKS AWESOME!

I would love to play with this robot even if tic tac toe is such a boring game!

The materials are cheap and the build looks very shoddy, but the result is great! This is the true spirit of hobby robot building. I hope you win the challenge.

You are a very talented person! :)

Very well done . I like the pen holder and auto-zero method .

It is very nice.

Awesome DJ Pants :) Again with minimal resources you've managed to impress a LOT :)

I love you're tic tac toe machine :D

All the best,

~ "Curry-alloy"


How the robot knows what box you chose and how the robot know that you choosed x or o as your sign .

I think you made your own buttons in order the robot to know what box you draw into but what about the other thing  I mention above ?

It always gives X regardless of whatever you are writing. You can even write your name or give just a dot. Player can draw anything except the X.

I like the user interface, be careful that Apple doesn't steal your ideas :D

I agree with Chris that your robot's over all accuracy and the way that it adjust the pen to the correct height was impressive.

As usual you have done a fantastic job with minimal materials.


Bonus points for the robot "getting angry" and scribbling across the board.

This is amaizing! I love the way it moves. Cool design! I really enjoyed watching it play! Keep it up! :D Hope to see more from you!

Its the auto-zero on the pen that did it for me. Its that "let go, tap, grab" routine so the bot knows how long the pen is. So simple, so fool-proof, such works-every-time. Not to mention, that even with servos running the thing, it "tapped" in exactly the same spot each time. All with drawer glides! 

Well done.