Sensor report - project 4
From Physical Programming
the code:
int reedSwitch = 5;
long startTime = 0;
int revsPer = 0;
float runningAve = 0;
long lastSeen = 0;
void setup()
{
pinMode(reedSwitch, INPUT); Serial.begin(9600); startTime = millis();
}
// TODO: build an average out of more samples
void loop()
{digitalWrite(13, LOW);
if(millis() < (startTime + 2000)){
if(digitalRead(reedSwitch) && (millis() > lastSeen + 300)){
digitalWrite(13, HIGH);
revsPer++;
lastSeen = millis();
Serial.print("lastSeen:");
Serial.println(lastSeen:"; }
}
else {
runningAve = (runningAve + revsPer)/2;
revsPer = 0;
startTime = millis();
Serial.print("two ave :");
Serial.println(runningAve);
Serial.print("RPM: ");
Serial.println(runningAve * 30);
}
}
So as you can see, the programming calls for two loops to be set up. In the second loop, a set of variables are described through ‘if’ and ‘else’ loops. This determines what will be shown on the screen.
The variables RPM, last Seen and two ave are printed into the computer screen.
Last seen shows the time lapsed in milliseconds, RPM relates to the speed of the wheel spins and two ave shows the average from two previous samples taken from the bike.
Bibliography
File:Reed switch (aka).jpg. (2005, April 29). Retrieved September 10, 2010, from Wikimedia Commons: www.commons.wikimedia.org
Arduino Perpetual Pendulum. (2008, May 28). Retrieved September 20, 2010, from Sheep Dog Guides: http://sheepdogguides.com/arduino/aht8pendu.htm
FAQ on Reed Switches and Reed Sensors. (2009). Retrieved September 30, 2010, from Reed Relays and Electronics India Limited: http://www.reed-sensor.com/Notes/General_Reed_Switch_Theory.htm
Stationary bike speedometer with Arduino and reed switch. (2009, nvember 21). Retrieved october 1, 2010, from Ideas for Dozens: http://www.urbanhonking.com/ideasfordozens/2009/11/stationary_bike_speedometer_wi.html
What is a Reed Switch. (2010, September 9). Retrieved September 15, 2010, from Wise Geek: http://www.wisegeek.com/what-is-a-reed-switch.htm
