Hello all,
I am fairly new to programming and Arduino, and I would like to ask for some help with my current project.
The project that I am building is an airbrake mechanism for a model rocket. Flaps are to deployed at a preset altitude to slow the rocket down before reaching a specific altitude. BMP280 is used to measure altitude, and three servos will be triggered to pull open the flaps when the preset altitude is reached.
I would like to use a debounce button as an on/off button to trigger the BMP280 to start reading the altitude.
In my experiment with the code, I set the threshold to one meter, so if I move the sensor one meter higher than initial altitude measured (launchSiteAltitude), the flaps should be deployed.
I utilized a state machine to organize the code. In the "ARMED" phrase, I plan to press the button once to switch on an LED light, and when the LED light is on, it triggers the launch input and then the BMP280 will read and save the altitude reading as the starting altitude. I added a Serial.println to indicate "launch" in the serial monitor if the launch phrase is triggered.
The things is that I pressed the button but nothing really happened. I wonder if the code that I used in the "ARMED" phrase is incorrect.
If you can see where the mistake is, please let me know. Attached is the codes and a hand drawn schematic.
P.S. the debounce button code worked when the debounce button codes were execute alone. It just didn't do what I hope it would do when I incorporated it to my airbrake codes.
Thanks!
#include <Servo.h> // Include the Servo.h library
#include <BMP280_DEV.h> // Include the BMP280_DEV.h library
const int buttonPin = 2; // the number of the pushbutton pin
const int ledPin = 13; // the number of the LED pin
int ledState = HIGH; // the current state of the output pin
int buttonState; // the current reading from the input pin
int lastButtonState = LOW; // the previous reading from the input pin
int servoPin1 = 9; // the number of servo pin 1
int servoPin2 = 10; // the number of servo pin 2
int servoPin3 = 11; // the number of servo pin 3
int servoPos = 0; //the starting servo position
Servo Myservo1; //define servo 1
Servo Myservo2; //define servo 2
Servo Myservo3; //define servo 3
float temperature, pressure, altitude; // Create the temperature, pressure and altitude variables
BMP280_DEV bmp280;
unsigned long lastDebounceTime = 0; // the last time the output pin was toggled
unsigned long debounceDelay = 50; // the debounce time; increase if the output flickers
enum StateMachine { DISARMED,
ARMED,
LAUNCH,
DEPLOY,
ABORT
} stateMachine = DISARMED;
bool armedInput = false, launchInput = false, abortInput = false;
bool servosActivated = false;
float currentAltitude, launchSiteAltitude;
float threshold = 1.0f; // Altitude above launch site in meters
void initializeBarometer()
{
bmp280.begin(); // Default initialisation, place the BMP280 into SLEEP_MODE
//bmp280.setPresOversampling(OVERSAMPLING_X4); // Set the pressure oversampling to X4
//bmp280.setTempOversampling(OVERSAMPLING_X1); // Set the temperature oversampling to X1
//bmp280.setIIRFilter(IIR_FILTER_4); // Set the IIR filter to setting 4
bmp280.setTimeStandby(TIME_STANDBY_1000MS); // Set the standby time to 1 seconds
bmp280.startNormalConversion(); // Start BMP280 continuous conversion in NORMAL_MODE
}
void initializeServos()
{
Myservo1.attach(servoPin1);
Myservo2.attach(servoPin2);
Myservo3.attach(servoPin3);
}
void initializeDebounceButton()
{
pinMode(buttonPin, INPUT);
pinMode(ledPin, OUTPUT);
digitalWrite(ledPin, ledState); // set initial LED state
}
void debounceButton()
{
// read the state of the switch into a local variable:
int reading = digitalRead(buttonPin);
// check to see if you just pressed the button
// (i.e. the input went from LOW to HIGH), and you've waited long enough
// since the last press to ignore any noise:
// If the switch changed, due to noise or pressing:
if (reading != lastButtonState) {
// reset the debouncing timer
lastDebounceTime = millis();
}
if ((millis() - lastDebounceTime) > debounceDelay) {
// whatever the reading is at, it's been there for longer than the debounce
// delay, so take it as the actual current state:
// if the button state has changed:
if (reading != buttonState) {
buttonState = reading;
// only toggle the LED if the new button state is HIGH
if (buttonState == HIGH) {
ledState = !ledState;
}
}
}
// set the LED:
digitalWrite(ledPin, ledState);
// save the reading. Next time through the loop, it'll be the lastButtonState:
lastButtonState = reading;
}
void activateServos ()
{
Myservo1.write(90);
Myservo2.write(90);
Myservo3.write(90);
}
void setup()
{
initializeBarometer(); //done
initializeServos(); //done
Myservo1.write(0);
Myservo2.write(0);
Myservo3.write(0);
initializeDebounceButton(); //done
Serial.begin(115200); // Initialise the serial port
}
void loop()
{
if (bmp280.getMeasurements(temperature, pressure, altitude)) // Check if the measurement is complete
{
Serial.print(temperature); // Display the results
Serial.print(F("*C "));
Serial.print(pressure);
Serial.print(F("hPa "));
Serial.print(altitude);
Serial.println(F("m"));
}
switch (stateMachine)
{
case DISARMED:
stateMachine = ARMED;
break;
case ARMED:
debounceButton ();
launchInput = digitalRead(ledPin);
bmp280.getAltitude(launchSiteAltitude);
if (launchInput == true)
{
stateMachine == LAUNCH;
}
if (stateMachine == LAUNCH)
Serial.println("launch");
break;
case LAUNCH:
altitude = bmp280.getAltitude(currentAltitude) - launchSiteAltitude;
if (altitude > threshold)
{
stateMachine = DEPLOY;
}
break;
case DEPLOY:
if (servosActivated == false)
{
activateServos();
servosActivated = true;
}
break;
case ABORT:
// Add abort code here...
break;
default:
break;
}
}
