ardupilot/Tools/Pozyx/IndoorLoiter/IndoorLoiter.ino

#include <Time.h>
#include <TimeLib.h>

#include <Pozyx.h>
#include <Pozyx_definitions.h>

/*//#include <mavlink.h>*/
#include "C:\Users\rmackay9\Documents\GitHub\ardupilot\Build.ArduCopter\libraries\GCS_MAVLink\include\mavlink\v2.0\common\mavlink.h"
#include <SoftwareSerial.h>
#include <Wire.h>
/*#include <Time.h> // download from https://github.com/PaulStoffregen/Time */
//#include "C:\Users\rmackay9\Documents\GitHub\Time\Time.h"

////////////////// Pozyx Prams //////////////////////////////

#define NUM_ANCHORS 4
// the network id of the anchors: change these to the network ids of your anchors.
uint16_t anchors[4] = { 0x601C, // (0,0)
                        0x6020, // x-axis
                        0x6057, // y-axis
                        0x605E};     

// only required for manual anchor calibration. 
// Please change this to the coordinates measured for the anchors
int32_t anchors_x[NUM_ANCHORS] = {0,    18600, 0,     18600};    // anchor x-coorindates in mm (horizontal)
int32_t anchors_y[NUM_ANCHORS] = {0,    0,     10000, 10000};    // anchor y-coordinates in mm (vertical)
int32_t heights[NUM_ANCHORS] =   {1420, 0,     0,     1450};     // anchor z-coordinates in mm

////////////////// MAVLINK Prams //////////////////////////////
#define LATITUDE_BASE (36.324187 * 1.0e7)
#define LONGITUDE_BASE (138.639212 * 1.0e7)
uint8_t buf[MAVLINK_MSG_ID_GPS_INPUT_LEN];
int32_t latitude = 0;
int32_t longitude = 0;

// RX TX serial for flight controller ex) Pixhawk
// https://github.com/PaulStoffregen/AltSoftSerial

SoftwareSerial fcboardSerial(10, 11); // rx, tx

////////////////////////////////////////////////

void setup()
{
  Serial.begin(115200);
  fcboardSerial.begin(57600);
  
  if (Pozyx.begin() == POZYX_FAILURE) {
    Serial.println(("ERR: shield"));
    delay(100);
    abort();
  }
  
  Serial.println(("V1.0"));

  // clear all previous devices in the device list
  Pozyx.clearDevices();
     
  //int status = Pozyx.doAnchorCalibration(POZYX_2_5D, 10, num_anchors, anchors, heights);
  /*int status = Pozyx.doAnchorCalibration(POZYX_2D, 10, num_anchors, anchors, heights);
  if (status != POZYX_SUCCESS) {
    Serial.println(status);
    Serial.println(("ERROR: calibration"));
    Serial.println(("Reset required"));
    delay(100);
    abort();
  }*/
  
  // if the automatic anchor calibration is unsuccessful, try manually setting the anchor coordinates.
  // fot this, you must update the arrays anchors_x, anchors_y and heights above
  // comment out the doAnchorCalibration block and the if-statement above if you are using manual mode
  SetAnchorsManual();

  printCalibrationResult();
  Serial.println(("Waiting.."));
  delay(5000);

  Serial.println(("Starting: "));
}

void loop()
{  
  coordinates_t position;
  
  int status = Pozyx.doPositioning(&position, POZYX_2_5D, 1000);
  //int status = Pozyx.doPositioning(&position);
  
  if (status == POZYX_SUCCESS) {
    // print out the result
    printCoordinates(position);

    // send GPS MAVLINK message
    SendGPSMAVLinkMessage(position);
  } else {
    Serial.println("fail");
  }
}

// function to print the coordinates to the serial monitor
void printCoordinates(coordinates_t coor)
{  
  Serial.print("x:");
  Serial.print(coor.x);
  print_tab();
  Serial.print("y:");
  Serial.print(coor.y);
  print_tab();
  Serial.print("z:");
  Serial.print(coor.z);
  print_tab();
  Serial.print("lat:");
  Serial.print(latitude);
  print_tab();
  Serial.print("lng:");
  Serial.print(longitude);
  print_tab();
  Serial.println(); 
}

void print_comma()
{  
    Serial.print(",");
}

void print_tab()
{  
    Serial.print("\t");
}

#define LOCATION_SCALING_FACTOR_INV_MM 0.08983204953368922f
#define DEG_TO_RAD      (M_PI / 180.0f)

float longitude_scale(uint32_t lat)
{
    static int32_t last_lat = 0;
    static float scale = 1.0;
    if (labs(last_lat - lat) < 100000) {
        // we are within 0.01 degrees (about 1km) of the
        // previous latitude. We can avoid the cos() and return
        // the same scale factor.
        return scale;
    }
    scale = cosf(lat * 1.0e-7f * DEG_TO_RAD);
    if (scale < 0.01f) {
      scale = 0.01f;
    }
    if (scale > 1.0f) {
      scale = 1.0f;
    }
    last_lat = lat;
    return scale;
}

void location_offset(int32_t &lat, int32_t &lng, int32_t offset_north_mm, int32_t offset_east_mm)
{
    int32_t dlat = offset_north_mm * LOCATION_SCALING_FACTOR_INV_MM;
    int32_t dlng = (offset_east_mm * LOCATION_SCALING_FACTOR_INV_MM) / longitude_scale(lat);
    lat += dlat;
    lng += dlng;
}

// print out the anchor coordinates (also required for the processing sketch)
void printCalibrationResult()
{
  uint8_t list_size;
  int status;

  status = Pozyx.getDeviceListSize(&list_size);
  Serial.print("list: ");
  Serial.println(status*list_size);
  
  if (list_size == 0) {
    Serial.println("Cal fail.");
    Serial.println(Pozyx.getSystemError());
    return;
  }
  
  uint16_t device_ids[list_size];
  status &= Pozyx.getDeviceIds(device_ids,list_size);
  
  Serial.println(("Cal:"));
  Serial.print(("Anchors found: "));
  Serial.println(list_size);
  
  coordinates_t anchor_coor;
  
  for (int i=0; i<list_size; i++) {
    Serial.print("A0x");
    Serial.print(device_ids[i], HEX);
    print_comma();
    status = Pozyx.getDeviceCoordinates(device_ids[i], &anchor_coor);
    Serial.print(anchor_coor.x);
    print_comma();
    Serial.print(anchor_coor.y);
    print_comma();
    Serial.println(anchor_coor.z);
    
  }    
}

// function to manually set the anchor coordinates
void SetAnchorsManual()
{
  int i=0;
  
  for (i=0; i<NUM_ANCHORS; i++) {
   device_coordinates_t anchor;
   anchor.network_id = anchors[i];
   anchor.flag = 0x1; 
   anchor.pos.x = anchors_x[i];
   anchor.pos.y = anchors_y[i];
   anchor.pos.z = heights[i];
   Pozyx.addDevice(anchor);
 }
}

// GPS MAVLink message using Pozyx potision
void SendGPSMAVLinkMessage(coordinates_t position)
{
  // Initialize the required buffers 
  mavlink_message_t msg; 
  
  /**
 * @brief Pack a gps_input message
 * @param system_id ID of this system
 * @param component_id ID of this component (e.g. 200 for IMU)
 * @param msg The MAVLink message to compress the data into
 *
 * @param time_usec Timestamp (micros since boot or Unix epoch)
 * @param gps_id ID of the GPS for multiple GPS inputs
 * @param ignore_flags Flags indicating which fields to ignore (see GPS_INPUT_IGNORE_FLAGS enum).  All other fields must be provided.
 * @param time_week_ms GPS time (milliseconds from start of GPS week)
 * @param time_week GPS week number
 * @param fix_type 0-1: no fix, 2: 2D fix, 3: 3D fix. 4: 3D with DGPS. 5: 3D with RTK
 * @param lat Latitude (WGS84), in degrees * 1E7
 * @param lon Longitude (WGS84), in degrees * 1E7
 * @param alt Altitude (AMSL, not WGS84), in m (positive for up)
 * @param hdop GPS HDOP horizontal dilution of position in m
 * @param vdop GPS VDOP vertical dilution of position in m
 * @param vn GPS velocity in m/s in NORTH direction in earth-fixed NED frame
 * @param ve GPS velocity in m/s in EAST direction in earth-fixed NED frame
 * @param vd GPS velocity in m/s in DOWN direction in earth-fixed NED frame
 * @param speed_accuracy GPS speed accuracy in m/s
 * @param horiz_accuracy GPS horizontal accuracy in m
 * @param vert_accuracy GPS vertical accuracy in m
 * @param satellites_visible Number of satellites visible.
 * @return length of the message in bytes (excluding serial stream start sign)
 */
 
  uint16_t ignore_flags = GPS_INPUT_IGNORE_FLAG_VEL_HORIZ|
                          GPS_INPUT_IGNORE_FLAG_VEL_VERT|
                          GPS_INPUT_IGNORE_FLAG_SPEED_ACCURACY|
                          GPS_INPUT_IGNORE_FLAG_HORIZONTAL_ACCURACY|
                          GPS_INPUT_IGNORE_FLAG_VERTICAL_ACCURACY;
  uint32_t time_week_ms = 0;
  uint16_t time_week = 0;

  make_gps_time(time_week_ms, time_week);

  // adjust position
  latitude = LATITUDE_BASE;
  longitude = LONGITUDE_BASE;
  location_offset(latitude, longitude, position.y, position.x);

  uint16_t len = mavlink_msg_gps_input_pack(
                    1,
                    0,
                    &msg,
                    micros(),       // time_usec,
                    0,              // gps_id,
                    ignore_flags,
                    time_week_ms,   // time_week_ms,
                    time_week,      // time_week,
                    3,              // fix_type,
                    latitude,       // latitude,
                    longitude,      // longitude,
                    10,             // altitude,
                    1.0f,           // hdop,
                    1.0f,           // vdop,
                    0.0f,           // vn
                    0.0f,           // ve
                    0.0f,           // vd
                    0.0f,           // speed_accuracy
                    0.0f,           // horiz_accuracy
                    0.0f,           // vert_accuracy,
                    14              // satellites_visible
                    );

  // Copy the message to send buffer 
  len = mavlink_msg_to_send_buffer(buf, &msg);
  
  // Send message
  fcboardSerial.write(buf, len);

}

// calculate GPS time
// based ardupilot/libraries/AP_GPS/GPS_Backend.cpp
void make_gps_time(uint32_t &time_week_ms, uint16_t &time_week)
{
    uint8_t year, mon, day, hour, min, sec;
    uint16_t msec;
    time_t now_time = now();

    year = ::year(now_time);
    mon  = ::month(now_time);
    day  = ::day(now_time);

    uint32_t v = millis();
    msec = v % 1000; v /= 1000;
    sec  = v % 100; v /= 100;
    min  = v % 100; v /= 100;
    hour = v % 100; v /= 100;

    int8_t rmon = mon - 2;
    if (0 >= rmon) {    
        rmon += 12;
        year -= 1;
    }

    // get time in seconds since unix epoch
    uint32_t ret = (year/4) - 15 + 367*rmon/12 + day;
    ret += year*365 + 10501;
    ret = ret*24 + hour;
    ret = ret*60 + min;
    ret = ret*60 + sec;

    // convert to time since GPS epoch
    ret -= 272764785UL;

    // get GPS week and time
    time_week = ret / (7*86400UL);
    time_week_ms = (ret % (7*86400UL)) * 1000;
    time_week_ms += msec;
}