+/*
+ * Calculate class to process accelerometer data
+ *
+ * @author Kai Rasilainen
+ * @copyright (c) 2010 Speed Freak team
+ * @license http://opensource.org/licenses/gpl-license.php GNU Public License
+ */
+
#include "calculate.h"
#include <math.h>
const double G_ACCELERATION = 9.80665;
const double SECONDS_IN_HOUR = 3600;
+const double AIR_DENSITY = 1.225;
+const double WATTS_PER_HORSEPOWER = 745.69987158227025;
-Calculate::Calculate() {
+const double carFrontalArea = 1.5;
+const double dragCoefficient = 0.31;
+const int carWeight = 850;
+Calculate::Calculate()
+{
this->reset();
-
}
-Calculate::~Calculate() {
-}
+Calculate::~Calculate()
+{
-void Calculate::reset() {
+}
+void Calculate::reset()
+{
averageSpeed = 0;
+ averagePower = 0;
+ peakPower = 0;
+ currentPower = 0;
currentSpeed = 0;
+ maxSpeed = 0;
distanceTraveled = 0;
lastAcceleration = 0;
lastDistance = 0;
lastSpeed = 0;
numOfIterations = 0;
totalTime = 0;
+ count = 0;
+
+ speedCheckPoints.append(10);
+ speedCheckPoints.append(20);
+ speedCheckPoints.append(30);
+ speedCheckPoints.append(40);
+
}
-/* Getters and setters
- */
-double Calculate::AverageSpeed()
+/**
+ * This is a main function for calculating various parameters. Accelerometer
+ * provides currentAcceleration and calling function measures time (seconds).
+ * This function should be called 20-30 times/second to minimize
+ * calculation error.
+
+ * To be added: ---
+ */
+void Calculate::calculateParameters(double currentAcceleration, double seconds)
+{
+ double force, power1, power2;
+
+ currentAcceleration *= G_ACCELERATION;
+ numOfIterations++;
+ totalTime = (totalTime + seconds);
+
+ // v=v0 + a*t
+ // v(n) = v(n-1)+(a(n) + a(n-1))*(seconds)/2
+
+ // First integration of acceleration provides speed
+ currentSpeed = (lastSpeed + (((currentAcceleration + lastAcceleration) * seconds) / 2));
+
+ // Update maximum speed
+ if (currentSpeed > maxSpeed)
+ maxSpeed = currentSpeed;
+
+ // Second integration: distance.
+ distanceTraveled = (lastDistance + (((currentSpeed + lastSpeed) * seconds) / 2));
+
+ // Average speed
+ averageSpeed = (distanceTraveled / totalTime);
+
+ // F=ma
+ force = (carWeight * currentAcceleration);
+
+ power1 = (force * currentSpeed);
+
+ power2 = ((AIR_DENSITY * (pow(currentSpeed, 3)
+ * (carFrontalArea * dragCoefficient))) / 2);
+
+ currentPower = ((power1 + power2) / WATTS_PER_HORSEPOWER);
+
+ // Save peak power
+ if ((currentPower > peakPower))
+ {
+ peakPower = currentPower;
+ }
+
+ if ((currentPower > 0))
+ {
+ averagePower = (averagePower + currentPower);
+ }
+ else
+ {
+ numOfIterations--;
+ }
+
+ // Checkpoints
+ if ((lastSpeed == 0))
+ {
+ lastCheckpoint = 0;
+ }
+
+ // List of checkpoints
+ if (!(speedCheckPoints.isEmpty()))
+ {
+ foreach (double speed, speedCheckPoints)
+ {
+ if ((lastCheckpoint != floor(speed)) && (floor(getCurrentSpeed()) == floor(speed)))
+ {
+ emit checkPointReached(totalTime, getCurrentSpeed());
+ lastCheckpoint = floor(getCurrentSpeed());
+ }
+ }
+ }
+
+ // Check for movement
+ accelStoppedCheck(currentAcceleration);
+
+ lastSpeed = currentSpeed;
+ lastAcceleration = currentAcceleration;
+ lastDistance = distanceTraveled;
+}
+
+/**
+ * This function checks if acceleration has stopped for
+ * a short period of time. Velocity is set to zero to avoid
+ * distance errors.
+ */
+void Calculate::accelStoppedCheck(double currentAcceleration)
+{
+ // counting number of acceleration samples that equals zero
+ if (currentAcceleration==0) {
+ count++;
+ } else {
+ count = 0;
+ }
+
+ // if count exceeds 25, we assume that velocity is zero
+ if (count >= 25)
+ {
+ currentSpeed=0;
+ }
+}
+
+// Getters and setters
+
+double Calculate::getAverageSpeed()
{
return averageSpeed;
}
-void Calculate::AverageSpeed(double value)
+
+void Calculate::setAverageSpeed(double value)
{
averageSpeed = value;
}
-double Calculate::CurrentSpeed()
+
+double Calculate::getCurrentSpeed()
{
return currentSpeed;
}
-void Calculate::CurrentSpeed(double value)
+
+void Calculate::setCurrentSpeed(double value)
{
currentSpeed = value;
}
-double Calculate::DistanceTraveled()
+
+double Calculate::getDistanceTraveled()
{
return distanceTraveled;
}
-void Calculate::DistanceTraveled(double value)
+
+void Calculate::setDistanceTraveled(double value)
{
distanceTraveled = value;
}
-double Calculate::LastAcceleration()
+
+double Calculate::getLastAcceleration()
{
return lastAcceleration;
}
-void Calculate::LastAcceleration(double value)
+
+void Calculate::setLastAcceleration(double value)
{
lastAcceleration = value;
}
-double Calculate::LastDistance()
+
+double Calculate::getLastDistance()
{
return lastDistance;
}
-void Calculate::LastDistance(double value)
+
+void Calculate::setLastDistance(double value)
{
lastDistance = value;
}
-double Calculate::LastSpeed()
+
+double Calculate::getLastSpeed()
{
return lastSpeed;
}
-void Calculate::LastSpeed(double value)
+
+void Calculate::setLastSpeed(double value)
{
lastSpeed = value;
}
-long Calculate::NumOfIterations()
+
+long Calculate::getNumOfIterations()
{
return numOfIterations;
}
-void Calculate::NumOfIterations(long value)
+
+void Calculate::setNumOfIterations(long value)
{
numOfIterations = value;
}
-double Calculate::TotalTime()
+
+double Calculate::getTotalTime()
{
return totalTime;
}
-void Calculate::TotalTime(double value)
+
+void Calculate::setTotalTime(double value)
{
totalTime = value;
}
-/*
- This is a main function for calculating various parameters. Accelerometer
- provides currentAcceleration and calling function measures time (seconds).
- This function should be called 20-30 times/second to minimize
- calculation error.
-
- To be added: params like horsepower.
- */
-void Calculate::CalculateParameters(double currentAcceleration, double seconds)
+double Calculate::getCurrentPower()
{
- numOfIterations++;
- totalTime = (totalTime + seconds);
-
- // v=v0 + a*t
- // v(n) = v(n-1)+(a(n) + a(n-1))*(seconds)/2
-
- /* First integration of acceleration provides speed
- */
- currentSpeed = (lastSpeed + (((currentAcceleration + lastAcceleration) * seconds) / 2));
-
- /* Second integration: distance.
- */
- distanceTraveled = (lastDistance + (((currentSpeed + lastSpeed) * seconds) / 2));
-
- /* Average speed
- */
- averageSpeed = (distanceTraveled / totalTime);
+ return currentPower;
+}
- /* Check for movement
- */
- accelStoppedCheck(currentAcceleration);
+void Calculate::setCurrentPower(double value)
+{
+ currentPower = value;
+}
- lastSpeed = currentSpeed;
- lastAcceleration = currentAcceleration;
- lastDistance = distanceTraveled;
+double Calculate::getPeakPower()
+{
+ return peakPower;
}
-/**
- * This function checks if acceleration has stopped for
- * a short period of time. Velocity is set to zero to avoid
- * distance errors.
- */
-void Calculate::accelStoppedCheck(double currentAcceleration) {
+void Calculate::setPeakPower(double value)
+{
+ peakPower = value;
+}
- // counting number of acceleration samples that equals zero
- if (currentAcceleration==0)
+double Calculate::getAveragePower()
+{
+ if (numOfIterations > 0)
{
- count++;
+ return (averagePower/numOfIterations);
}
else
{
- count = 0;
+ return 0;
}
+}
- // if count exceeds 25, we assume that velocity is zero
- if (count >= 25)
- {
- currentSpeed=0;
- }
+void Calculate::setAveragePower(double value)
+{
+ averagePower = value;
+}
+
+double Calculate::getMaxSpeed()
+{
+ return maxSpeed;
}
+void Calculate::setMaxSpeed(double value)
+{
+ maxSpeed = value;
+}