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authorLorenz Meier <lm@inf.ethz.ch>2013-08-21 18:13:01 +0200
committerLorenz Meier <lm@inf.ethz.ch>2013-08-21 18:13:01 +0200
commitfab110d21f147e5064ff140aadac649017fa466e (patch)
treeb41291188db4e5734353f0d09a0af306c58ed9f5 /src/modules/systemlib/airspeed.c
parent309ea8146055528c22395fca06b7a70b660c22b3 (diff)
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Moved math library to library dir, improved sensor-level HIL, cleaned up geo / conversion libs
Diffstat (limited to 'src/modules/systemlib/airspeed.c')
-rw-r--r--src/modules/systemlib/airspeed.c16
1 files changed, 10 insertions, 6 deletions
diff --git a/src/modules/systemlib/airspeed.c b/src/modules/systemlib/airspeed.c
index e01cc4dda..310fbf60f 100644
--- a/src/modules/systemlib/airspeed.c
+++ b/src/modules/systemlib/airspeed.c
@@ -42,7 +42,7 @@
#include <stdio.h>
#include <math.h>
-#include "conversions.h"
+#include <geo/geo.h>
#include "airspeed.h"
@@ -95,17 +95,21 @@ float calc_true_airspeed_from_indicated(float speed_indicated, float pressure_am
float calc_true_airspeed(float total_pressure, float static_pressure, float temperature_celsius)
{
float density = get_air_density(static_pressure, temperature_celsius);
+
if (density < 0.0001f || !isfinite(density)) {
- density = CONSTANTS_AIR_DENSITY_SEA_LEVEL_15C;
-// printf("[airspeed] Invalid air density, using density at sea level\n");
+ density = CONSTANTS_AIR_DENSITY_SEA_LEVEL_15C;
}
float pressure_difference = total_pressure - static_pressure;
- if(pressure_difference > 0) {
+ if (pressure_difference > 0) {
return sqrtf((2.0f*(pressure_difference)) / density);
- } else
- {
+ } else {
return -sqrtf((2.0f*fabsf(pressure_difference)) / density);
}
}
+
+float get_air_density(float static_pressure, float temperature_celsius)
+{
+ return static_pressure / (CONSTANTS_AIR_GAS_CONST * (temperature_celsius - CONSTANTS_ABSOLUTE_NULL_CELSIUS));
+}