Ladder Safety Alarm: Eastern Phoebes

How We Got Here

Because our project device was rather unique compared to what other groups were building and what we’ve seen before on the market, our team decided to first build the overall main electrical system while Tim CADed and printed the housing. After putting together a rough physical system and putting that into the housing and seeing how everything fit, we realize that we needed to adjust not only the system itself as we had other components that we have not yet implemented such as the laser and the battery, we also have to adjust the housing height as everything was crammed in we were not physically able to keep the cover on without the speaker being in the way. From there, we continued working on the physical electrical system and added new features file continuously testing while Tim designed the second housing prototype. The second housing was a lot better, but there were some areas that we needed to fix such as sanding down supports. After finalizing the housing itself, we worked on testing our code and revising until the sensors were working together for our project.

From our first presentation, we got a lot of feedback in terms of not necessarily the device itself, but more of the usage concern. Some people had questions about the orientation or even the way the device would be attached to the ladder and had us take these different perspectives into consideration when designing the housing itself as well. From there, we designed the housing to be attachable to Velcro so that Jayson could easily put it on ladders and take it off when needed. 

Process

 At least six images illustrating your process * Discussion about your decisionmaking as a team and any breakthrough or breakdown moments you had * Discussion about the extent to which you followed or didn't follow your original schedule 

Technical Details (Code)

/* * =================================================================
* PROJECT: Sentry Security System (Motion & Distance Triggered)
* GOAL: * - Monitor a "Safe Zone" using an Ultrasonic sensor and PIR Motion sensor.
* - ALERT ZONE (250cm): Trigger orange flashing lights and lower volume MP3.
* - DANGER ZONE (100cm + Motion): Trigger red fast-flashing lights,
* max volume MP3, and a motorized "shaking" laser pointer. *
* ARDUINO PINOUT: * - Pin 2: PIR Motion Sensor (Input)
* - Pin 3: Laser Pointer (Output via Transistor/Relay) * - Pin 4: Motion Status LED (Output) * - Pin 5: Servo Signal (PWM)
* - Pin 6: NeoPixel Data Pin
* - Pin 10: Software Serial RX (Connect to DFPlayer TX)
* - Pin 11: Software Serial TX (Connect to DFPlayer RX via 1k Resistor)
* - Pin 12: HC-SR04 Trig Pin * - Pin 13: HC-SR04 Echo Pin *
* DFPLAYER MINI PINOUT (Physical Pins): * - VCC: 5V (External power recommended) 

* - GND: Ground (Shared with Arduino) * - RX: To Arduino Pin 11 (via 1k Resistor)

* - TX: To Arduino Pin 10 

* - SPK1: Speaker Terminal (+)

* - SPK2: Speaker Terminal (-) 

* ================================================================= */ 

#include <Servo.h>

#include <Adafruit_NeoPixel.h>

#include <DFMiniMp3.h>

#include <SoftwareSerial.h>

class Mp3Notify;

Servo shakeServo;

SoftwareSerial secondarySerial(10, 11); // RX, TX

typedef DFMiniMp3<SoftwareSerial, Mp3Notify> DfMp3;

DfMp3 dfmp3(secondarySerial);

class Mp3Notify {

public:

  static void PrintlnSourceAction(DfMp3_PlaySources source, const char* action) {

    if (source & DfMp3_PlaySources_Sd) Serial.print("SD Card, ");

    Serial.println(action);

  }

  static void OnError([[maybe_unused]] DfMp3& mp3, uint16_t errorCode) {

    Serial.print("Com Error "); Serial.println(errorCode);

  }

  static void OnPlayFinished([[maybe_unused]] DfMp3& mp3, [[maybe_unused]] DfMp3_PlaySources source, uint16_t track) {

    Serial.print("Finished #"); Serial.println(track);  

  }

  static void OnPlaySourceOnline([[maybe_unused]] DfMp3& mp3, DfMp3_PlaySources source) { PrintlnSourceAction(source, "online"); }

  static void OnPlaySourceInserted([[maybe_unused]] DfMp3& mp3, DfMp3_PlaySources source) { PrintlnSourceAction(source, "inserted"); }

  static void OnPlaySourceRemoved([[maybe_unused]] DfMp3& mp3, DfMp3_PlaySources source) { PrintlnSourceAction(source, "removed"); }

};

// ------------------- PINS & CONFIG -------------------

const int motionPin = 2;

const int laserPointer = 3;

const int motionLed = 4;

const int servoMotion = 5;

const int trigPin = 12;

const int echoPin = 13;

#define LED_PIN 6

#define NUMPIXELS 16

Adafruit_NeoPixel strip(NUMPIXELS, LED_PIN, NEO_GRB + NEO_KHZ800);

const int alertDistance = 250;

const int dangerDistance = 100;

// State Tracking

bool isAudioActive = false;

unsigned long lastPingTime = 0;

const int pingInterval = 50;

// Servo Settings

int centerPos = 90;

int shakeRange = 30;

int shakeSpeed = 15;

int shakeDirection = 1;

int currentPos = centerPos;

unsigned long lastShakeTime = 0;

void setup() {

  Serial.begin(115200);

  pinMode(motionLed, OUTPUT);

  pinMode(trigPin, OUTPUT);

  pinMode(echoPin, INPUT);

  pinMode(motionPin, INPUT);

  pinMode(laserPointer, OUTPUT);

  shakeServo.attach(servoMotion);

  shakeServo.write(centerPos);

  strip.begin();

  strip.show();

  Serial.println("Initializing MP3...");

  dfmp3.begin();

  dfmp3.setVolume(80);

  delay(500);

  Serial.println("System Ready.");

}

long getDistance() {

  digitalWrite(trigPin, LOW);

  delayMicroseconds(2);

  digitalWrite(trigPin, HIGH);

  delayMicroseconds(10);

  digitalWrite(trigPin, LOW);

  long duration = pulseIn(echoPin, HIGH, 25000);

  if (duration == 0) return 999;

  return duration * 0.034 / 2;

}

void shakeLaser() {

  if (millis() - lastShakeTime > shakeSpeed) {

    lastShakeTime = millis();

    currentPos += shakeDirection;

    if (currentPos > centerPos + shakeRange || currentPos < centerPos - shakeRange) {

      shakeDirection *= -1;

    }

    shakeServo.write(currentPos);

  }

}

void loop() {

  dfmp3.loop();

  static long distance = 999;

  if (millis() - lastPingTime >= pingInterval) {

    lastPingTime = millis();

    distance = getDistance();

  }

  int motionDetected = digitalRead(motionPin);

  digitalWrite(motionLed, motionDetected);

  bool inDanger = (distance > 0 && distance < dangerDistance && motionDetected == HIGH);

  bool inAlert = (distance > 0 && distance < alertDistance);

  // ---------------- LOGIC ENGINE ----------------

  if (inDanger) {

    // DANGER ZONE: Full volume, laser shake, fast red flash

    if (!isAudioActive) {

      dfmp3.playGlobalTrack(1);

      isAudioActive = true;

    }

    dfmp3.setVolume(100);

    shakeLaser();

    digitalWrite(laserPointer, HIGH);

    flashNeoPixels(255, 0, 0, 50);

  }

  else if (inAlert) {

    // ALERT ZONE: Lower volume, no laser, slow orange flash

    if (!isAudioActive) {

      dfmp3.playGlobalTrack(1);

      isAudioActive = true;

    }

    dfmp3.setVolume(60);

    digitalWrite(laserPointer, LOW);

    shakeServo.write(centerPos);

    flashNeoPixels(255, 50, 0, 150);

  }

  else {

    // SAFE ZONE: Audio off, lights off

    if (isAudioActive) {

      dfmp3.stop();

      isAudioActive = false;

    }

    digitalWrite(laserPointer, LOW);

    shakeServo.write(centerPos);

    strip.clear();

    strip.show();

  }

}

void flashNeoPixels(int r, int g, int b, int speedDelay) {

  static unsigned long lastFlash = 0;

  static bool ledState = false;

  if (millis() - lastFlash > speedDelay) {

    lastFlash = millis();

    ledState = !ledState;

    if (ledState) {

      for (int i = 0; i < NUMPIXELS; i++) strip.setPixelColor(i, strip.Color(r, g, b));

    } else {

      strip.clear();

    }

    strip.show();

  }

}