adxrs610: Initial implementation

This module was developed and tested on a ADXRS610 Gyro Beakout
board.

http://www.dfrobot.com/index.php?route=product/product&product_id=642

Signed-off-by: Jon Trulson <jtrulson@ics.com>
Signed-off-by: Abhishek Malik <abhishek.malik@intel.com>

src/adxrs610/CMakeLists.txt

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+set (libname "adxrs610")
+set (libdescription "upm ADXRS610 gyroscope")
+set (module_src ${libname}.cxx)
+set (module_h ${libname}.h)
+upm_module_init()

src/adxrs610/adxrs610.cxx

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+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2015 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <iostream>
+
+#include "adxrs610.h"
+
+using namespace std;
+using namespace upm;
+
+ADXRS610::ADXRS610(int dPin, int tPin, float aref) :
+  m_aioData(dPin), m_aioTemp(tPin)
+{
+  // ADC resolution of data and temp should be the same...
+  m_aRes = (1 << m_aioData.getBit());
+  m_aref = aref;
+
+  setZeroPoint(calibrateZeroPoint());
+  setDeadband(0.0);
+
+  m_centerVolts = aref / 2.0;
+
+}
+
+ADXRS610::~ADXRS610()
+{
+}
+
+float ADXRS610::getDataVolts()
+{
+  int val = m_aioData.read();
+
+  return(float(val) * (m_aref / float(m_aRes)));
+}
+
+float ADXRS610::getTemperatureVolts()
+{
+  int val = m_aioTemp.read();
+
+  return(float(val) * (m_aref / float(m_aRes)));
+}
+
+float ADXRS610::calibrateZeroPoint(unsigned int samples)
+{
+  // The gyro should be in a stable, non-moving state
+
+  float sum = 0;
+  for (int i=0; i<samples; i++)
+    sum += getDataVolts();
+
+  return sum / samples;
+}
+
+float ADXRS610::getTemperature()
+{
+  float tempV = getTemperatureVolts();
+  
+  // nominal 2.5 volts at 25C
+  if (tempV > m_centerVolts)
+    return (m_temperatureNom + ((tempV - m_centerVolts) / m_temperatureCoeff));
+  else
+    return (m_temperatureNom - ((m_centerVolts - tempV) / m_temperatureCoeff));
+}
+
+float ADXRS610::getAngularVelocity()
+{
+  float dataV = getDataVolts();
+
+  // check the deadband
+  if (dataV < (m_zeroPoint + m_deadband) &&
+      dataV > (m_zeroPoint - m_deadband))
+    return 0.0;
+  
+  if (dataV > m_zeroPoint)
+    return ((dataV - m_zeroPoint) / m_degreeCoeff);
+  else
+    return -((m_zeroPoint - dataV) / m_degreeCoeff);
+}

src/adxrs610/adxrs610.h

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+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2015 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#pragma once
+
+#include <iostream>
+#include <string>
+#include <mraa/aio.hpp>
+
+namespace upm {
+  /**
+   * @brief DFRobot ADXRS610 Gyro Beakout board
+   * @defgroup adxrs610 libupm-adxrs610
+   * @ingroup dfrobot analog compass
+   */
+
+  /**
+   * @library adxrs610
+   * @sensor adxrs610
+   * @comname DFRobot ADXRS610 Gyro Beakout board
+   * @altname ADXRS610
+   * @type compass
+   * @man dfrobot
+   * @web http://www.dfrobot.com/index.php?route=product/product&product_id=642
+   * @con analog
+   *
+   * @brief DFRobot ADXRS610 Gyro Beakout board
+   *
+   * The ADXRS610 is a MEMS based single axis gyroscope with a range
+   * of +/- 300 degrees/sec.  It also incorporates a temperature
+   * sensing unit that can be used for advanced calibration.
+   *
+   * This sensor returns an analog voltage proportional to the
+   * rotation about the Z-axis in degrees/sec.  The temperature
+   * component returns a proportional analog values in degrees C.
+   *
+   * This driver was developed using the DFRobot ADXRS610 Gyro Beakout board.
+   *
+   * @snippet adxrs610.cxx Interesting
+   */
+
+  class ADXRS610 {
+  public:
+
+    /**
+     * ADXRS610 constructor
+     *
+     * @param dPin Analog pin to use for DATAOUT
+     * @param tPin Analog pin to use for temperature measurement
+     * @param aref Analog reference voltage; default is 5.0 V
+     */
+    ADXRS610(int dPin, int tPin, float aref=5.0);
+
+    /**
+     * ADXRS610 destructor
+     */
+    ~ADXRS610();
+
+    /**
+     * Returns the voltage detected on the DATA analog pin
+     *
+     * @return The detected voltage
+     */
+    float getDataVolts();
+
+    /**
+     * Returns the voltage detected on the TEMP analog pin
+     *
+     * @return The detected voltage
+     */
+    float getTemperatureVolts();
+
+    /**
+     * This method allows you to specify a deadband region around the
+     * zero point of the gyro (at rest).  This can be used as a
+     * primitive filter to ignore movment around the zero point.
+     *
+     * @param deadband The voltage around the zero point which will be
+     * ignored
+     */
+    void setDeadband(float deadband) { m_deadband = deadband; };
+
+    /**
+     * Set the zero point.  This is the point measured and averaged
+     * when the sensor is not moving.  It is set at construction time
+     * (averaged over a number of samples), but can be overriden here.
+     *
+     * @param zeroPoint The averaged zero point of the sensor at rest
+     */
+    void setZeroPoint(float zeroPoint) { m_zeroPoint = zeroPoint; };
+
+    /**
+     * This method samples the data pin samples times to produce an
+     * average.  This value can then be used as the zero point
+     * (setZeroPoint()).
+     *
+     * @param samples the number of samples to take an average over.
+     * The default is 50.  
+     * @return the average of the reading over samples times.
+     */
+    float calibrateZeroPoint(unsigned int samples=50);
+
+    /**
+     * Return the zero point value.
+     *
+     * @return the current zero point value
+     */
+    float getZeroPoint() { return m_zeroPoint; };
+
+    /**
+     * Return the measured temperature in Celcius.  Note, the
+     * datasheet says that this value is very repeatable, but is not
+     * an accurate absolute temperature.
+     *
+     * @return the current temperature in C
+     */
+    float getTemperature();
+
+    /**
+     * Return the measured angular velocity in degrees/sec.
+     *
+     * @return the current angular velocity in degrees/sec
+     */
+    float getAngularVelocity();
+
+  protected:
+    mraa::Aio m_aioData;
+    mraa::Aio m_aioTemp;
+
+  private:
+    float m_aref;
+    // ADC resolution
+    int m_aRes;
+
+    // measured or set zero point value
+    float m_zeroPoint;
+    // desired deadband, default is 0.0
+    float m_deadband;
+
+    // aref / 2
+    float m_centerVolts;
+
+    // volts per degree / second (typ)
+    static const float m_degreeCoeff = 0.006;
+
+    // volts per degree C (typ)
+    static const float m_temperatureCoeff = 0.009;
+    // nominal temperature at m_centerVolts
+    static const float m_temperatureNom = 25.0;
+  };
+}
+
+

src/adxrs610/javaupm_adxrs610.i

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+%module javaupm_adxrs610
+%include "../upm.i"
+
+%{
+    #include "adxrs610.h"
+%}
+
+%include "adxrs610.h"

src/adxrs610/jsupm_adxrs610.i

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+%module jsupm_adxrs610
+%include "../upm.i"
+
+%{
+    #include "adxrs610.h"
+%}
+
+%include "adxrs610.h"

src/adxrs610/pyupm_adxrs610.i

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+%module pyupm_adxrs610
+%include "../upm.i"
+
+%feature("autodoc", "3");
+
+%include "adxrs610.h"
+%{
+    #include "adxrs610.h"
+%}