gnss_computer.h

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#pragma once
 
 
 
#include <Arduino.h>
#include <Wire.h>
#include "hummingbird_config.h"
#include "maths/vectors.h"
#include "TinyGPS++.h"
#include "constants.h"
#include "sensor_systems/ubx_cfg_messages.h"
 
 
#if defined(DEBUG) && defined(DEBUG_PORT)
    /* Print GNSS debug messages to the debug serial port */
    #define GNSS_DEBUG
#endif
 
 
 
 
constexpr uint32_t GNSS_POS_LOCK_TIMEOUT = 120000;
 
/* Baud rate that the unconfigured GPS has when powered up */
constexpr int32_t GNSS_DEFAULT_BAUD = 9600;
 
/* Minimum number of GNSS satellites to ensure a valid fix */
constexpr uint32_t GNSS_MIN_SATS = 5;
 
/* I2C address of the UBLOX GPS module */
constexpr uint8_t GNSS_I2C_ADDR = 0x42;
 
/* I2C buffer size of the device. 32 bytes for Arduino Nano and Teensy 4.1 */
constexpr uint16_t GNSS_I2C_BUFFSIZE = 32;
 
 
/* Possible baud rates for the GNSS sensor */
// typedef enum
// {
//     GNSS_BAUD_9600,     // 9600 serial baud rate (default when NEO-M8N powers up)
//     GNSS_BAUD_38400,    // 38.4k serial baud rate
//     GNSS_BAUD_115200,   // 115.2K serial baud rate
//     GNSS_BAUD_230400    // 230.4k serial baud rate
// } GNSSBaudRates_t;
 
/* Possible GNSS networks to connect to. */
typedef enum
{
    GNSS_NET_GPS,           // Connect to GPS network, max. 10Hz on NEO-M8N
    GNSS_NET_GLONASS,       // Connect to GLONASS network, max. 10Hz on NEO-M8N
    GNSS_NET_GPS_GLONASS    // Connect to both GPS and GLONASS, max. 5Hz on NEO-M8N
} GNSSNetworks_t;
 
/* Various dynamic models for the GPS receiver's sensor fusion algorithms */
typedef enum
{
    GNSS_DYNAMICS_PORTABLE,     // Portable dynamic model, 12000m alt, 310m/s hvel, 50m/s vvel, med. dev.
    GNSS_DYNAMICS_PEDESTRIAN,   // Pedestrian dynamic model, 9000m alt, 30m/s hvel, 20m/s vvel, small dev.
    GNSS_DYNAMICS_AIRBORNE_1G    // Airborne 1G dynamic model, 50000m alt, 100m/s hvel, 100m/s vvel, large dev.
} GNSSDynamics_t;
 
/* GPS fix status codes */
typedef enum
{
    // GNSS_FIX_NO_GPS,    // No GPS sensor connected/detected
    GNSS_FIX_NONE,      // Receiving valid GPS data, but with no position lock
    GNSS_FIX_2D,        // Receiving valid GPS data with a 2D lock
    GNSS_FIX_3D         // Receiving valid GPS data with a 3D lock
} GNSSFix_t;
 
/* GPS inavigation rates */
typedef enum
{
    GNSS_NAVRATE_5HZ = 5,   // 5 Hz navigation rate/output rate
    GNSS_NAVRATE_10HZ = 10  // 10 Hz navigation rate/output rate
} GNSSNavRate_t;
 
 
/* GPS status types */
typedef enum
{
    // GNSS_I2C_COMM_ERROR  // If an error was encountered communicating to the GPS over I2C
    // GNSS_CONFIG_SUCCESS,  // Successful configuration
    // GNSS_CONFIG_NO_DEVICE,  // No GPS sensor connected/detected
    // GNSS_CONFIG_RECONNECT_ERROR,  // When we change the baud rate and cannot reconnect to the GPS
    // GNSS_CONFIG_NO_HOME_LOCATION  // No home location specified
} GNSSStatus_t;
 
 
 
class GNSSComputer
{
public:
    GNSSComputer(TwoWire *userWire = &GPS_I2C);
    ~GNSSComputer() {};
 
    // Do not allow copies (singleton)
    static GNSSComputer &GetInstance();
    GNSSComputer(const GNSSComputer &) = delete;
    GNSSComputer &operator=(const GNSSComputer &) = delete;
 
    bool ConfigureDevice(
        GNSSNetworks_t userNetwork  = GNSS_NET_GPS, 
        GNSSDynamics_t userDynModel = GNSS_DYNAMICS_PEDESTRIAN,
        GNSSNavRate_t userODR       = GNSS_NAVRATE_10HZ
        );
    bool WaitForSatellites(uint32_t nSats = GNSS_MIN_SATS);
    bool ListenForData();
 
    TinyGPSPlus NMEAParser;          // TinyGPS++ GPS object
    // TinyGPSCustom PDOPParser;  // Parse GxGSA for PDOP
 
protected:
private:
    
    // GGA
    // ortho. height
    // geoid sep.
    // gps quality/fix type?
    // TinyGPSCustom GeoidSepParser;  // Parse GxGGA for geoid separation [m] (Sep = AltWGS84 - AltMSL)
 
    // GSA
    // pdop
    // hdop
    // vdop
    // TinyGPSCustom PDOPParser;  // Parse GxGSA for PDOP
    // TinyGPSCustom HDOPParser;  // Parse GxGSA for HDOP
    // TinyGPSCustom VDOPParser;  // Parse GxGSA for VDOP
 
    // VTG
    // mag. track/cog
    // true track/cog
    // speed, kts
    // speed over gnd, kph
    // TinyGPSCustom TrueTrackParser;  // Parse GxVTG for true track [deg]
    // TinyGPSCustom GroundSpeedParser;  // Parse GxVTG for ground speed [kts]
 
    Vectord PosLLA;     // [rad, rad, m] Lat, lon, altitude
    Vectorf PosECEF;    // [m, m, m] ECEF position
    Vectorf VelECEF;    // [m/s, m/s, m/s] ECEF velocity
    void SendUBXConfigMessage(const uint8_t *msg, size_t len);
    // LPF for smoothing gps pos (to smooth out impulses/sharp changes)
    // LPF for smoothing altitude
private:
    bool isConfigured;  // True if ConfigureDevice() was called, false if not
    uint32_t lastDataCheck;  // [ms] millis() of when last checked for new data.
    uint32_t dataPollWait;  // [ms] Period between polling for new data. 
    int32_t gpsBaud;  // Baud rate for serial connection
    float navTs;  // [sec] GPS navigation sample period
    float navRate;  // [Hz] GPS navigation rate
    
 
    // GNSSBaudRates_t gpsBaud;        // Baud rate for GPS serial communication
    GNSSNetworks_t network;         // Satellite network(s) that the GPS is connected to
    GNSSDynamics_t dynamicModel;    // Dynamic model for the GPS fusion algorithms
    GNSSNavRate_t updateRate;       // [Hz] navigation rate from gps
    TwoWire *gpsWire;      // HW I2C bus that the GPS is connected to
};
 
// Only one instance
extern GNSSComputer &GPS;