MAVLink communication via ESP32

ArduCopter
1

Hi everyone,

I’m trying to communicate an ESP32 with a Pixhawk 2.4.8 to obtain GPS data using the TELEM2 port on the Pixhawk. However, I am not receiving any messages, and the data does not appear in the MAVLink Inspector. Could anyone provide some advice?

Below are the latest parameters from the Pixhawk and the Arduino code:

full_parameters_08_08_24_16.55.param (13.9 KB)

#include <Marvelmind.h>
#include <MAVLink.h>

MarvelmindHedge hedge;
PositionValuePro positionVP;
RawIMUValue rIMUV;
FusionIMUValuePro fIMUVP;
char print_buffer[128];

const int res = 1; // Resolution to print values
float radiansToDegrees = 57.2957795f; // radians to degrees
float roll, pitch, yaw;

unsigned long t1;
const unsigned long period = 100;
long baudrate = 57600;

void setup() {
Serial.begin(baudrate); // Monitor serial
Serial2.begin(baudrate, SERIAL_8N1, 16, 17); // Configura Serial2 con los pines GPIO 16 (RX) y GPIO 17 (TX)
Serial1.begin(baudrate, SERIAL_8N1, 18, 19); // Configura Serial1 para la comunicación con la Pixhawk

hedge.begin(&Serial2);
t1 = millis();
}

void loop() {
hedge.read();
if (millis() - t1 > period) {

if (hedge.getPositionFromMarvelmindHedge(true, &positionVP)) {
  Serial.print("Position Hedge: ");
  Serial.print(" X=");
  Serial.print(positionVP.x, res);
  Serial.print(", Y=");
  Serial.print(positionVP.y, res);
  Serial.print(", Z=");
  Serial.print(positionVP.z, res);
  Serial.print(", Angle=");
  Serial.print(positionVP.angle, res);
  Serial.println();
}
// Enviar datos a la Pixhawk
sendToPixhawk();

t1 = millis();

}
}

void sendToPixhawk() {
mavlink_message_t msg;
uint8_t buffer[MAVLINK_MAX_PACKET_LEN];

// Enviar datos de posición local_position_ned
if (hedge.getPositionFromMarvelmindHedge(true, &positionVP)) {
mavlink_msg_local_position_ned_pack(1, 200, &msg, millis(), positionVP.x / 1000.0, positionVP.y / 1000.0, positionVP.z / 1000.0, 0, 0, 0);
uint16_t len = mavlink_msg_to_send_buffer(buffer, &msg);
Serial1.write(buffer, len);
}

// Enviar datos de posición vision_position_estimate
if (hedge.getPositionFromMarvelmindHedge(true, &positionVP)) {
float pos_x = positionVP.x / 1000.0;
float pos_y = positionVP.y / 1000.0;
float pos_z = positionVP.z / 1000.0;
float covariance[21] = {0}; // Inicializar el arreglo de covarianza a ceros
uint8_t reset_counter = 0; // Inicializar el contador de reinicio

mavlink_msg_vision_position_estimate_pack(1, 200, &msg, millis() * 1000, pos_x, pos_y, pos_z, 0, 0, 0, covariance, reset_counter);
uint16_t len = mavlink_msg_to_send_buffer(buffer, &msg);
Serial1.write(buffer, len);

}
}

2

you either need to request the stream rates or set the SR2 values manually.

3

These??

image
image1153×495 138 KB

4

yes, you have them set to 0 so you won’t be getting any mavlink data streamed from the port. set them all to 5 and it should work for any data you want to get over mavlink.

5

While your approach here is scalable, somewhat elegant, and arguably the correct method, there’s a quick and dirty alternative:

Simply tie a wire into the TX pin of the GPS output and sample it via serial “sniffing.” You’d have to parse the messages, of course, but it’d be a more direct mechanism if you only want GPS data.