Revision 1:1a4694de3548, committed 2015-12-08

Comitter:

whatnick

Date:

Tue Dec 08 02:14:33 2015 +0000

Parent:

0:39935bb3c1a1

Commit message:

Added Magnetometer basic calibration

Changed in this revision

diff -r 39935bb3c1a1 -r 1a4694de3548 MPU9150.h
--- a/MPU9150.h	Sun Jun 29 22:48:08 2014 +0000
+++ b/MPU9150.h	Tue Dec 08 02:14:33 2015 +0000
@@ -541,7 +541,44 @@
    dest2[2] = (float)accel_bias[2]/(float)accelsensitivity;
 }
 
-
+void magcalMPU9150(float * dest1) 
+{
+  uint16_t ii = 0, sample_count = 0;
+  int32_t mag_bias[3] = {0, 0, 0};
+  int16_t mag_max[3] = {0, 0, 0}, mag_min[3] = {0, 0, 0}, mag_temp[3] = {0, 0, 0};
+ 
+  //LOG("Mag Calibration: Wave device in a figure eight until done!");
+  wait(4);
+  
+   sample_count = 64;
+   for(ii = 0; ii < sample_count; ii++) {
+    readMagData(mag_temp);  // Read the mag data   
+    for (int jj = 0; jj < 3; jj++) {
+      if (ii == 0) {
+        mag_max[jj] = mag_temp[jj]; // Offsets may be large enough that mag_temp[i] may not be bipolar! 
+        mag_min[jj] = mag_temp[jj]; // This prevents max or min being pinned to 0 if the values are unipolar...
+      } else {
+        if(mag_temp[jj] > mag_max[jj]) mag_max[jj] = mag_temp[jj];
+        if(mag_temp[jj] < mag_min[jj]) mag_min[jj] = mag_temp[jj];
+      }
+    }
+    wait_ms(135);  // at 8 Hz ODR, new mag data is available every 125 ms
+   }
+ 
+//    Serial.println("mag x min/max:"); Serial.println(mag_max[0]); Serial.println(mag_min[0]);
+//    Serial.println("mag y min/max:"); Serial.println(mag_max[1]); Serial.println(mag_min[1]);
+//    Serial.println("mag z min/max:"); Serial.println(mag_max[2]); Serial.println(mag_min[2]);
+ 
+    mag_bias[0]  = (mag_max[0] + mag_min[0])/2;  // get average x mag bias in counts
+    mag_bias[1]  = (mag_max[1] + mag_min[1])/2;  // get average y mag bias in counts
+    mag_bias[2]  = (mag_max[2] + mag_min[2])/2;  // get average z mag bias in counts
+    
+    dest1[0] = (float) mag_bias[0]*mRes*magCalibration[0];  // save mag biases in G for main program
+    dest1[1] = (float) mag_bias[1]*mRes*magCalibration[1];   
+    dest1[2] = (float) mag_bias[2]*mRes*magCalibration[2];          
+ 
+   //LOG("Mag Calibration done!");
+}
 // Accelerometer and gyroscope self test; check calibration wrt factory settings
 void MPU9150SelfTest(float * destination) // Should return percent deviation from factory trim values, +/- 14 or less deviation is a pass
 {

diff -r 39935bb3c1a1 -r 1a4694de3548 N5110.lib
--- a/N5110.lib	Sun Jun 29 22:48:08 2014 +0000
+++ b/N5110.lib	Tue Dec 08 02:14:33 2015 +0000
@@ -1,1 +1,1 @@
-http://mbed.org/users/onehorse/code/Adfs/#28c629d0b0d0
+http://mbed.org/users/eencae/code/N5110/#ba8addc061ea

diff -r 39935bb3c1a1 -r 1a4694de3548 main.cpp
--- a/main.cpp	Sun Jun 29 22:48:08 2014 +0000
+++ b/main.cpp	Tue Dec 08 02:14:33 2015 +0000
@@ -104,6 +104,8 @@
     wait(1);
     MPU9150.initMPU9150(); 
     pc.printf("MPU9150 initialized for active data mode....\n\r"); // Initialize device for active mode read of acclerometer, gyroscope, and temperature
+    MPU9150.magcalMPU9150(magbias);
+    pc.printf("Mag cal done....\n\r"); // Initialize device for active mode read of magnetometer
     MPU9150.initAK8975A(magCalibration);
     pc.printf("AK8975 initialized for active data mode....\n\r"); // Initialize device for active mode read of magnetometer
    }
@@ -127,10 +129,11 @@
     mRes = 10.*1229./4096.; // Conversion from 1229 microTesla full scale (4096) to 12.29 Gauss full scale
     // So far, magnetometer bias is calculated and subtracted here manually, should construct an algorithm to do it automatically
     // like the gyro and accelerometer biases
+    /*
     magbias[0] = -5.;   // User environmental x-axis correction in milliGauss
     magbias[1] = -95.;  // User environmental y-axis correction in milliGauss
     magbias[2] = -260.; // User environmental z-axis correction in milliGauss
- 
+    */
 
  while(1) {
   

diff -r 39935bb3c1a1 -r 1a4694de3548 mbed.bld
--- a/mbed.bld	Sun Jun 29 22:48:08 2014 +0000
+++ b/mbed.bld	Tue Dec 08 02:14:33 2015 +0000
@@ -1,1 +1,1 @@
-http://mbed.org/users/mbed_official/code/mbed/builds/0b3ab51c8877
\ No newline at end of file
+http://mbed.org/users/mbed_official/code/mbed/builds/165afa46840b
\ No newline at end of file