ITTT - Cat Laser

Heey my name is Rens Kuilman. For a school project (If This Then That) we had to make something using the Arduino. After a few misses I decided to make a random laser, which I a lazy cat owner could use the get his lazy cat to move.

• Arduino Uno [1x]
• SG90 Mini Servo [2x]
• Pinwires [6x]

• Red Laser Module 5V 650nm [1x]

At first I wanted to make a small moveable robot like machine. But I quickly realized that something like this wasn't that doable with the skill level I was on (and still are on). It kind of felt like banging my head against a rock.

I did have more images and video's of this process, but 1 broken phone and moving house later and lost most of it.

I played around with sound/pitch and even made a prototype using lego.

I also tried working on a controller for a game, but scrapped it because it wasn't what they wanted us to make for a project like this.

It also turned out pretty boring and was just the same as already excisting controllers

Eventually I decided to just make something. Something I would enjoy working on, and so I did...

Using a cardboard box and some beer coasters I quickly put together a prototype. The pen was a temporarily replacement for the laser module.

Code:

#include <Servo.h>

Servo servoOne;
Servo servoTwo;

void setup() {
  
  Serial.begin(9600);

  servoOne.attach(3);
  servoTwo.attach(2);
}

void loop() {

    // Uncomment these lines to align servo's
    //servoOne.write(0);
    //servoTwo.write(0);

    // Give servo's random angle
    servoOne.write(random(0, 30), random(30, 80));
    servoTwo.write(random(20, 160), random(30, 80));
      
    delay(1000);
}

As you can see in the video. The servo's move way to quickly. The cat wouldn't even see the laser pointer before it moved again.

The problem in the previous step was that you can't adjust the speed of a servo. This would lead to almost instant movement.

Luckily someone made a library that gives servo's a little bit more controllability.

VarSpeedServo

Using this I could add random speeds to the servo's every time they move.

Code

#include <VarSpeedServo.h>

VarSpeedServo servoOne;
VarSpeedServo servoTwo;

void setup() {

  Serial.begin(9600);
  servoOne.attach(3);
  servoTwo.attach(2);
}

void loop() {

    // Uncomment these lines to align servo's
    //servoOne.write(0);
    //servoTwo.write(0);  

    // Random angle, random speed.
    servoOne.slowmove(random(0, 30), random(30, 80));
    servoTwo.slowmove(random(20, 160), random(30, 80));
    delay(1000);
}

Because I used coasters for the paper prototype, I already had a good idea of how I wanted it to look.

https://puu.sh/FVWaX/b145786331.png

With some help of my brother who has a 3D printen and also has waaaay more experience using one, we made a case for my project.

https://puu.sh/FVW8g/b6a29556fd.jpg

https://puu.sh/FVWcw/a6a0ae5251.jpg

https://puu.sh/FVWgp/d716158663.png

The top part has not been printed yet at the time of writing this.

Test assembly.

Fully assembled and soldered (missing cap, not yet printed)