DISCUSSION

Some written critiques that I received during the final critique of this project included a lot about the doors; one person said ​​”Extremely clean implementation, one critique I have is to implement the doors without tape, only because it contrasts against the uber clean implementation,” and another person said “It looks so nice! I think it would have been better if you put the trap doors as like wood or clear acrylic,” both of which are critiques that I fully agree with. My original plan was to cut the doors from acrylic, and my original plan for the acrylic was for it to either be colored (not clear) or to be clear and painted so that seeing inside looked less messy, but IDeATe lending was out of non-clear ¼” acrylic and I ran out of time on the doors, so they ended up being cardboard coated in silver tape. I don’t really love the way they turned out visually, but they worked in a pinch. Another critique I got was “Would like to see it so something like drop a snack through a servo connected trap door instead of having to manually open and close the doors,” which is another piece of critique that I agree with wholeheartedly; I originally wanted to use spring loaded hinges so the doors popped open, but I didn’t have them on hand and I worried about the servos being strong enough to hold them closed. This idea is super cool though — a snack dropping through a trap door would also help you walk up when the alarm goes off! 

I am pretty happy with how my project turned out. I ran into a LOT of issues (struggles with laser cutting, struggles with the libraries for the mp3 player) but I got through it and ended up with a project that did everything I set out to do, except stop the song when you flipped the ON/OFF switch. The ON/OFF switch worked otherwise, but when the song was playing, nothing else in the project responded to any input whatsoever until the song was done playing; this was a fault of me not being good at reading library documentation I think, and given a little more time I could have figured it out I think. I would have liked to use a mix of clear and colored acrylic maybe to hide the inner wiring, but people also seemed to like the clear acrylic, and I do understand the appeal of being able to see inside. I’m happy with how the LCD screen and the keypad work (except for during final critique, when the LCD screen got disconnected) and I think the little “Setting timer!” message, as well as the live countdown, are cute and were well-timed.

I learned that while I like laser cutting and CAD, it can be frustrating to do on a time crunch; I felt super stressed about not being able to access the laser room, so I rushed the CAD and then had to redo a lot of it over and over again due to silly mistakes made from rushing. In the future, I would like to work slower through the CAD to make sure that I do things correctly the first time around. My biggest challenge was perhaps the mp3 player library; I tried 3 libraries and couldn’t figure out how to integrate them into my code how I wanted to. In the future this is a process I would start earlier. I ignored the issue of not being able to stop the song for a while because I figured it would be an easy fix, but then after spending an hour or more trying to fix it, I realized it was definitely not an easy fix for me. Another issue I had was my wiring; I did a lot of soldering because I felt confident after the last project, but then the day before the project was due, I tried to put everything into my clear enclosure and suddenly everything stopped working. I spent about 3 hours trying to figure out the problem before I gave up on good problem solving and started just rapidly replacing every single wire and every single connection in the project out of desperation, which ended up fixing it. I thought I was “ahead” by getting the soldering done and the project working a few days before it was due, but I learned that it is not always as easy as “place the fully soldered assembly into the chassis” and that I should do that much sooner to avoid this in the future. 

If I was to build another iteration of this project, I would likely use different acrylic to let the wiring hide a little more, or do a much neater job of wiring. I would also make the doors out of a more “permanent” or nice looking material like wood or acrylic. I also would use a different library for the mp3 player so that I could stop the song!

CODE:

/*

Ella Sanfilippo CMU 60-223 Project 2 Code

This code is for an alarm clock with 3 doors that 

unlock via servo motors, and includes 3 switches

to control the servos and a master ON/OFF switch.

It uses an mp3 player for the alarm clock sound and 

features an LCD screen and a keypad for entering

the desired number of hours to sleep. 

Please see the textblock below for links to resources. 

*/

/*

PIN DIAGRAM:

12 -> left door switch

13 -> right door switch

A3 -> bottom door switch 

A5 -> main on/off switch

A0 -> left door servo 

A1 -> right door servo 

A2 -> bottom door servo 

10 & 11 -> mp3 player connections 

*/

#include <Servo.h>

#include <Wire.h>

#include <ezButton.h>

#include <Keypad.h>

#include "mp3tf16p.h"

#include <LiquidCrystal_I2C.h>

//LCD

LiquidCrystal_I2C screen(0x27, 16, 2);

const int LCDLONG = 250; // 4x/second

long LCDtimer = 0;

//SWITCHES

ezButton leftSwitch(12); // create ezButton object that attach to pin 12;

ezButton rightSwitch(13);

ezButton bottomSwitch(A3);

ezButton mainSwitch(A5);

Servo leftServo;

Servo rightServo;

Servo bottomServo;

//SEROVS

const int LEFT_PIN = A0;

const int RIGHT_PIN = A1;

const int BOTT_PIN = A2;

//KEYPAD

const byte ROWS = 4;

const byte COLS = 4;

//MP3 PLAYER

MP3Player mp3(10, 11); //pins 10 and 11

char hexaKeys[ROWS][COLS] = {

{ '1', '2', '3', 'A' },

{ '4', '5', '6', 'B' },

{ '7', '8', '9', 'C' },

{ '*', '0', '#', 'D' }

};

//TIMER

const int LONGENOUGH = 1000; // 1x/seconds

long timer = 0;

String inputString;

long inputInt;

bool counting = false;

unsigned long previousMillis;

unsigned long currentMillis;

unsigned long startMillis;

byte rowPins[ROWS] = { 9, 8, 7, 6 };

byte colPins[COLS] = { 5, 4, 3, 2 };

Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);

void setup() {

Serial.begin(9600);

leftSwitch.setDebounceTime(50); // set debounce time to 50 milliseconds

rightSwitch.setDebounceTime(50);

bottomSwitch.setDebounceTime(50);

mainSwitch.setDebounceTime(50);

leftServo.attach(LEFT_PIN);

rightServo.attach(RIGHT_PIN);

bottomServo.attach(BOTT_PIN);

screen.init();

screen.backlight();

mp3.initialize();

}

void loop() {

leftSwitch.loop();

rightSwitch.loop();

bottomSwitch.loop();

mainSwitch.loop();

char key = customKeypad.getKey();

int state = mainSwitch.getState();

if (leftSwitch.isPressed()) {

Serial.println("Left switch: OFF -> ON");

leftServo.write(180);

Serial.println("Left servo pos: 180");

}

if (leftSwitch.isReleased()) {

Serial.println("Left switch: ON -> OFF");

leftServo.write(90);

Serial.println("Left servo pos: 90");

}

if (rightSwitch.isPressed()) {

Serial.println("Right switch: OFF -> ON");

rightServo.write(180);

Serial.println("Right servo pos: 180");

}

if (rightSwitch.isReleased()) {

Serial.println("Right switch: ON -> OFF");

rightServo.write(90);

Serial.println("Right servo pos: 90");

}

if (bottomSwitch.isPressed()) {

Serial.println("Bottom switch: OFF -> ON");

bottomServo.write(180);

Serial.println("Bottom servo pos: 180");

}

if (bottomSwitch.isReleased()) {

Serial.println("Bottom switch: ON -> OFF");

bottomServo.write(90);

Serial.println("Bottom servo pos: 90");

}

if (state == HIGH) {

if (key) {

Serial.println(key);

}

if (key >= '0' && key <= '9') { // only act on numeric keys

inputString += key; // append new character to input string

screen.clear();

screen.setCursor(0,0);

screen.print("Set timer: ");

screen.setCursor(0,1);

inputInt = inputString.toInt();

screen.print(inputInt);

}

else if (key == '#') {

if (inputString.length() > 0) {

screen.clear();

screen.print("Setting timer!");

delay(1000); //1 sec delay

inputInt = inputString.toInt(); // YOU GOT AN INTEGER NUMBER

inputString = ""; // clear input

startMillis = millis(); //the start time

counting = true;

}

}

int inputMin = inputInt * 60; //inputInt is in hours; put in mins

int inputSec = inputMin * 60;

//int inputMillis = inputSec * 1000;

//FOR DEMO MODE:

int inputMillis = inputInt * 1000; //1 hour = 1 second for demo

if ((inputMillis - currentMillis) >= 0 && counting) {

currentMillis = millis() - startMillis;

}

if (counting && (inputMillis - currentMillis == 0)) {

counting = false;

screen.clear();

screen.setCursor(0,0);

Serial.println("DONE!");

screen.print("DONE!");

//when timer hits zero, servos open and music plays

leftServo.write(180);

rightServo.write(180);

bottomServo.write(180);

mp3.playTrackNumber(1, 20);

}

if (millis() - timer >= LONGENOUGH && counting) {

Serial.println();

Serial.println("Counting...");

Serial.println("Current seconds: ");

Serial.println(currentMillis / 1000);

Serial.println("Counting to: ");

Serial.println(inputMillis / 1000);

screen.clear();

screen.home();

screen.print("Time Remaining: ");

screen.setCursor(0, 1);

screen.print(inputMillis/1000 - currentMillis/1000);

timer = millis();

}

}

if(state==LOW){

//reset all

inputString = "";

counting = false;

screen.clear();

screen.setCursor(0,0);

screen.print("OFF");

//screen.noDisplay();

Serial.println("OFF");

delay(1000);

screen.noDisplay();

}

}

Resources used in code and circuits: 

For mp3 player: https://www.youtube.com/watch?v=PBdqgHj_AkU, https://forum.arduino.cc/t/need-help-with-my-wiring-fried-my-mp3-tf-16p/972975 

For keypad: https://www.allaboutcircuits.com/projects/use-a-keypad-with-your-arduino/, https://learn.adafruit.com/matrix-keypad/overview, https://www.farnell.com/datasheets/1359150.pdf, https://www.circuitbasics.com/how-to-set-up-a-keypad-on-an-arduino/#:~:text=Install%20the%20Library&text=This%20library%20takes%20care%20of,the%20library%2C%20then%20click%20install 

For timer: https://github.com/PaulStoffregen/Time, https://arduinogetstarted.com/faq/how-to-input-a-multiple-digits-number-using-the-keypad, https://www.instructables.com/Simple-Arduino-Timer/