Revision 2:ca1d3bef09a6, committed 2012-12-14

Comitter:

theschrade54

Date:

Fri Dec 14 05:05:35 2012 +0000

Parent:

1:67f60f68719f

Commit message:

Code to find max and avg deviation, max swing, or simple readings from a still HMC6352 compass. Can be used with motors to test error from magnetic interference.

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Motordriver.lib	Fri Dec 14 05:05:35 2012 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/littlexc/code/Motordriver/#3110b9209d3c

--- a/main.cpp	Sat Nov 27 12:15:56 2010 +0000
+++ b/main.cpp	Fri Dec 14 05:05:35 2012 +0000
@@ -1,21 +1,44 @@
-#include "HMC6352.h"
-
-HMC6352 compass(p9, p10);
-Serial pc(USBTX, USBRX);
-
-int main() {
-
-    pc.printf("Starting HMC6352 test...\n");
-    
-    //Continuous mode, periodic set/reset, 20Hz measurement rate.
-    compass.setOpMode(HMC6352_CONTINUOUS, 1, 20);
-
-    while (1) {
-
-        wait(0.1);
-
-        pc.printf("Heading is: %f\n", compass.sample() / 10.0);
-
-    }
-
-}
+#include "mbed.h"
+#include "motordriver.h"
+#include "HMC6352.h"
+
+// test program to verify compass integrity when run on motor and to determine filtering values. uncomment/comment motor sections to test.
+HMC6352 compass(p9, p10);
+Serial pc(USBTX, USBRX);
+//Motor left(p21, p22, p20, 1); // pwm, fwd, rev, has brake feature
+//Motor right(p24, p25, p27, 1);
+
+int main() {
+    float avgdev, dev, maxdev, swing, prevval, curval, minval, maxval = 0.0; //variables to measure swing, maxdev, and avg dev of measurements
+    long count = 0;
+    //float speed = .1;
+    pc.printf("Starting HMC6352 test...\n");
+    //left.speed(speed);
+    //right.speed(speed);
+    //Continuous mode, periodic set/reset, 20Hz measurement rate.
+    compass.setOpMode(HMC6352_CONTINUOUS, 1, 20);
+    wait(1);
+    //init math vals
+    curval = compass.sample()/10.0;
+    minval = curval;
+    maxval = curval;
+    while (1) {
+        count++; // for avg
+        prevval = curval;
+        curval = compass.sample()/10.0;
+        dev = abs(curval - prevval);
+        if (curval > maxval) {maxval = curval;}
+        if (curval < minval) {minval = curval;}
+        if (dev > maxdev)    {maxdev = dev;}    //largest deviation between two successive readings.
+        avgdev += dev; //divide avg dev in print statement
+        swing = maxval - minval; //swing is largest reading change possible from remaining stationary.
+        if (count % 10 == 1) {
+        pc.printf("Heading is: %f, Max Dev: %f, Avg Dev: %f, Swing: %f\n", curval, maxdev, avgdev/count, swing);
+            //if (speed < .8) {speed += .05;
+            //left.speed(speed);
+            //right.speed(speed);}
+        }
+        wait(0.05);
+    }
+
+}