I’m running a px4 sitl and using ros2, subscribing to the vehicle status, once in misson mode, I’m trying to switch to hold or loiter mode. To switch commands I’m using vehicle command topic. What is the param values for loiter and hold mode. I’m unable to find any ref.
import rclpy
from rclpy.node import Node
from rclpy.qos import QoSProfile, ReliabilityPolicy, HistoryPolicy, DurabilityPolicy
from px4_msgs.msg import VehicleCommand, VehicleStatus, VehicleLocalPosition
class Switch(Node):
def __init__(self):
super().__init__('switch_mode')
#Quality of service
qos_profile = QoSProfile(
reliability=ReliabilityPolicy.BEST_EFFORT,
durability=DurabilityPolicy.TRANSIENT_LOCAL,
history=HistoryPolicy.KEEP_LAST,
depth=1
)
# publishers
self.vehicle_command_publisher = self.create_publisher(
VehicleCommand,
'/fmu/in/vehicle_command',
10)
# subscribers
self.vehicle_status_subscriber = self.create_subscription(
VehicleStatus,
'/fmu/out/vehicle_status',
self.vehicle_status_callback,
qos_profile)
self.vehicle_local_position_subscriber = self.create_subscription(
VehicleLocalPosition,
'/fmu/out/vehicle_local_position',
self.vehicle_local_position_callback,
qos_profile)
self.in_mission_mode = False
self.takeoff_height = -4.0 # Adjust the takeoff height as needed
# vehicle local position callback
def vehicle_local_position_callback(self, msg):
self.vehicle_local_position = msg
# drone status callback
def vehicle_status_callback(self, msg):
self.get_logger().info(f"Vehicle status callback: {msg.nav_state}")
if msg.nav_state == VehicleStatus.NAVIGATION_STATE_AUTO_MISSION and self.vehicle_local_position.z < self.takeoff_height:
self.in_mission_mode = True
self.publish_vehicle_command(VehicleCommand.VEHICLE_CMD_DO_SET_MODE, param1 = 1.0)
self.get_logger().info('Vehicle command published')
#publishes command to drone
def publish_vehicle_command(self, command, **params):
"""Publish a vehicle command."""
msg = VehicleCommand()
msg.command = command
msg.param1 = params.get("param1", 0.0)
msg.param2 = params.get("param2", 0.0)
msg.param3 = params.get("param3", 0.0)
msg.param4 = params.get("param4", 0.0)
msg.param5 = params.get("param5", 0.0)
msg.param6 = params.get("param6", 0.0)
msg.param7 = params.get("param7", 0.0)
msg.target_system = 1
msg.target_component = 1
msg.source_system = 1
msg.source_component = 1
msg.from_external = True
msg.timestamp = int(self.get_clock().now().nanoseconds / 1000)
self.vehicle_command_publisher.publish(msg)
def main(args=None):
rclpy.init(args=args)
node = Switch()
rclpy.spin(node)
rclpy.shutdown()
if __name__=='__main__':
main()
