Demo 2: Edward Lu

Controllable Swinger

The purpose of my project is too add intractability to my Demo 1. There are five LTH-1550 photoreflective sensors glued unto a board and the user can move their hand over the board and control the position of the servo, allowing the ball to move!

I initially wanted to swing the board with the servo and have it balance the ball in the middle of the board with a PD controller, but unfortunately the ball wasn’t being recognized by the sensors and I was unable to find another, less opaque ball. 🙁 Out of time and out of luck, I revamped my idea to just control the servo with swipes. And it works pretty well!

#include <Servo.h&gt;

const int SENSOR_PIN1 = 7;
const int SENSOR_PIN2 = 6;
const int SENSOR_PIN3 = 5;
const int SENSOR_PIN4 = 4;
const int SENSOR_PIN5 = 3;
const int SERVO_PIN = 9;

Servo svo;

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);
  svo.attach(SERVO_PIN);
}

void loop() {
  short val1 = digitalRead(SENSOR_PIN1);
  short val2 = digitalRead(SENSOR_PIN2);
  short val3 = digitalRead(SENSOR_PIN3);
  short val4 = digitalRead(SENSOR_PIN4);
  short val5 = digitalRead(SENSOR_PIN5);
  
  if (val1) {
    svo.write(20);
  }
  else if (val2) {
    svo.write(50);
  }
  else if (val3) {
    svo.write(80);
  }
  else if (val4) {
    svo.write(110);
  }
  else if (val5) {
    svo.write(140);
  }
}

To improve this project, I would definitely add behaviors for the cases where multiple sensors are being activated. And maybe make a case to hide all my nasty wiring… 🙂