Bonjour !
Depuis quelques mois je bricole un petit projet à base d'un acceleromètre 9 axes (capteur bn0055) et je me rend compte que la qualité du cap fournis par le capteur est vraiment mauvaise (parfois des erreurs de plus de 20° !).
J'ai bien calibré le capteur et tout les status affichent une résolution max.
Auriez vous des solutions à me proposer pour améliorer mes valeurs de cap ?
Des référence de capteurs plus fiable ?
Par avance merci !
Willy
ta un programme a montrer?
L'erreur ne vient pas de mon code (c'est le code fournis par l'exemple) mais du capteur je pense ...
Néanmoins si tu veux voir le code test le voici :
/****************************************************************************
* Copyright (C) 2011 - 2014 Bosch Sensortec GmbH
*
* Euler.ino
* Date: 2014/09/09
* Revision: 3.0 $
*
* Usage: Example code to stream Euler data
*
****************************************************************************
/***************************************************************************
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#include "NAxisMotion.h" //Contains the bridge code between the API and the Arduino Environment
#include <Wire.h>
NAxisMotion mySensor; //Object that for the sensor
unsigned long lastStreamTime = 0; //To store the last streamed time stamp
const int streamPeriod = 20; //To stream at 50Hz without using additional timers (time period(ms) =1000/frequency(Hz))
void setup() //This code is executed once
{
//Peripheral Initialization
Serial.begin(115200); //Initialize the Serial Port to view information on the Serial Monitor
I2C.begin(); //Initialize I2C communication to the let the library communicate with the sensor.
//Sensor Initialization
mySensor.initSensor(); //The I2C Address can be changed here inside this function in the library
mySensor.setOperationMode(OPERATION_MODE_NDOF); //Can be configured to other operation modes as desired
mySensor.setUpdateMode(MANUAL); //The default is AUTO. Changing to MANUAL requires calling the relevant update functions prior to calling the read functions
//Setting to MANUAL requires fewer reads to the sensor
}
void loop() //This code is looped forever
{
if ((millis() - lastStreamTime) >= streamPeriod)
{
lastStreamTime = millis();
mySensor.updateEuler(); //Update the Euler data into the structure of the object
mySensor.updateCalibStatus(); //Update the Calibration Status
Serial.print("Time: ");
Serial.print(lastStreamTime);
Serial.print("ms ");
Serial.print(" H: ");
Serial.print(mySensor.readEulerHeading()); //Heading data
Serial.print("deg ");
Serial.print(" A: ");
Serial.print(mySensor.readAccelCalibStatus()); //Accelerometer Calibration Status (0 - 3)
Serial.print(" M: ");
Serial.print(mySensor.readMagCalibStatus()); //Magnetometer Calibration Status (0 - 3)
Serial.print(" G: ");
Serial.print(mySensor.readGyroCalibStatus()); //Gyroscope Calibration Status (0 - 3)
Serial.print(" S: ");
Serial.print(mySensor.readSystemCalibStatus()); //System Calibration Status (0 - 3)
Serial.println();
}
}
Avez vous des perturbations électromagnétiques autour du capteur ? (Moteurs / bobines par exemple)
Bonjour !
Déjà j'ai constaté récemment que l'erreur n'est en fait pas si importante que ce que j'ai annoncé (je comparais les valeurs obtenues par mon shield à celles de la boussole de mon téléphone, pas très précis...) !
Suite à ton commentaire J-M-L j'ai réalisé que mettre des relais près de mon magnétomètre n'était pas très malin ... Donc j'ai testé et là surprise : l'activation des relais ne change pas d'un seul degrés mon cap !
Je suis un peu étonné d'un tel résultat mais ça va dans le bon sens ...
il doit y avoir un bon blindage 
avez vous essayé avec d'autres librairies (par exemple Adafruit_BNO055)