disconnect

R2026b

Disconnect local MAVLink client from UDP or serial ports

Syntax

disconnect(mavlink)

disconnect(mavlink,connection)

Description

disconnect(mavlink) closes all active UDP and serial connections of the local MAVLink client mavlink.

disconnect(mavlink,connection) closes the MAVLink client mavlink connection identified by connection.

Examples

Establish Serial Connection with Pixhawk Board

Connect a local MAVLink client to a serial port and establish communication with a Pixhawk^® 4 board running PX4^® firmware by exchanging heartbeat messages.

Create a mavlinkdialect object using the common.xml file.

dialect = mavlinkdialect("common.xml");

Create a local MAVLink client by using the mavlinkio object.

gcs = mavlinkio(dialect);

Store the remote MAVLink client information by using the mavlinkclient object. This code stores information for a Pixhawk board with a system ID of 1 and a component ID of 1.

uav = mavlinkclient(gcs,1,1)

uav = 
  mavlinkclient with properties:

         SystemID: 1
      ComponentID: 1
    ComponentType: "Unknown"
    AutopilotType: "Unknown"

Connect the local MAVLink client to the same serial port as the Pixhawk board by using the connect function. In this code, the Pixhawk board uses the "COM5" port.

connect(gcs,"Serial",SerialPort="COM5");

Create a heartbeat microservice object.

heartbeat = mavlinkmicroservice(gcs,"heartbeat");

Start sending heartbeat messages to the Pixhawk board by using the start function.

start(heartbeat,uav,"Serial",SerialPort="COM5")

If the Pixhawk board replies with heartbeat messages, the local MAVLink client establishes a connection to it.

Verify that a connection has been established by using the listClients function. Note that the heartbeat messages include the ComponentType and AutopilotType information of the Pixhawk board.

listClients(gcs)

ans = 2×4 table
    SystemID    ComponentID       ComponentType             AutopilotType     
    ________    ___________    ____________________    _______________________

      255            1            "MAV_TYPE_GCS"        "MAV_AUTOPILOT_INVALID"
       1             1         "MAV_TYPE_QUADROTOR"       "MAV_AUTOPILOT_PX4"

Verify that the ComponentType and AutopilotType properties of the mavlinkclient object have been automatically updated to match the heartbeat message values.

uav

uav = 
  mavlinkclient with properties:

         SystemID: 1
      ComponentID: 1
    ComponentType: "MAV_TYPE_QUADROTOR"
    AutopilotType: "MAV_AUTOPILOT_PX4"

To stop the connection, first stop the heartbeat message stream.

stop(heartbeat,uav)

Then, disconnect the local MAVLink client from the serial port.

disconnect(gcs)

Connect Simulated UAV to QGroundControl Through UDP Connection

Connect a local MAVLink client to QGroundControl by exchanging heartbeat messages over UDP,

Open QGroundControl.

Create a mavlinkdialect object using the common.xml file.

dialect = mavlinkdialect("common.xml");

Create a local MAVLink client that represents a simulated UAV by creating a mavlinkio object with these settings:

• MAVLink message definition — dialect

• MAVLink system ID — 1

• MAVLink component ID — 1

• MAVLink component type — MAV_TYPE_QUADROTOR

• MAVLink autopilot type — MAV_AUTOPILOT_GENERIC

uav = mavlinkio(dialect,SystemID=1,ComponentID=1,AutopilotType="MAV_AUTOPILOT_GENERIC", ...
    ComponentType="MAV_TYPE_QUADROTOR");

Store the remote MAVLink client information that represents QGroundControl. By default, QGroundControl has a system ID of 255 and a component ID of 190.

qgc = mavlinkclient(uav,255,190);

Connect the local MAVLink client to a UDP port by using the connect function.

connect(uav,"UDP");

Verify that the local MAVLink client has connected to a UDP port by using the listConnections function.

connectionTable = listConnections(uav)

connectionTable = 
   1x2 table
       ConnectionName         ConnectionInfo     
       ______________      ___________________ 
   
        "Connection1"      "UDP@0.0.0.0:55371"

Create a heartbeat microservice object.

heartbeat = mavlinkmicroservice(uav,"heartbeat");

Specify the host address and port of QGroundControl.

qgcHost = "127.0.0.1";
qgcPort = 14550;

Start sending heartbeat messages to QGroundControl by using the start function.

start(heartbeat,qgc,"UDP",RemoteHost=qgcHost,RemotePort=qgcPort);

If QGroundControl replies with heartbeat messages, the local MAVLink client establishes a connection to it.

Verify that the connection has been established by using the listClients function.

listClients(uav)

ans = 2×4 table
    SystemID    ComponentID       ComponentType             AutopilotType     
    ________    ___________    ____________________    _______________________

      255           190          "MAV_TYPE_GCS"        "MAV_AUTOPILOT_INVALID"
       1             1        "MAV_TYPE_QUADROTOR"     "MAV_AUTOPILOT_GENERIC"

To stop the connection, first stop the heartbeat message stream.

stop(heartbeat,gcs)

Then, disconnect the local MAVLink client from the UDP port.

disconnect(uav)

Input Arguments

mavlink — Local MAVLink client

mavlinkio object

Local MAVLink client, specified as a mavlinkio object.

connection — Identifying connection name

string scalar

Identifying connection name, specified as a string scalar.

Example: Connection1

Version History

Introduced in R2019a