执行路点导航Py demo发现总是提示 FollowWaypoints action server is not available

[liyihongcug]

ros2 FollowWaypoints action server is not available （ros2 foxy版本 ubuntu20）

但ros2命令执行发现 FollowWaypoint 的node action service都在
而且rviz2是可以做导航的。（按钮驱动）
用的是navigation2 (humble的)
主要代码如下：
from geometry_msgs.msg import PoseStamped
from nav2_simple_commander.robot_navigator import BasicNavigator, TaskResult
import rclpy
from rclpy.duration import Duration
import tf_transformations

def main():
rclpy.init()

navigator = BasicNavigator()

# 位置初始化
# initial_pose = PoseStamped()
# initial_pose.header.frame_id = 'map'
# initial_pose.header.stamp = navigator.get_clock().now().to_msg()
# initial_pose.pose.position.x = 3.45
# initial_pose.pose.position.y = 2.15
# initial_pose.pose.orientation.z = 1.0
# initial_pose.pose.orientation.w = 0.0
# navigator.setInitialPose(initial_pose)

navigator.waitUntilNav2Active()

#添加导航点
goal_poses = []
goal_pose1 = PoseStamped()
goal_pose1.header.frame_id = 'map'
goal_pose1.header.stamp = navigator.get_clock().now().to_msg()
goal_pose1.pose.position.x = 1.5
goal_pose1.pose.position.y = -0.55
yaw=0
quat=tf_transformations.quaternion_from_euler(0,0,yaw)
goal_pose1.pose.orientation.x = quat[0]
goal_pose1.pose.orientation.y = quat[1]
goal_pose1.pose.orientation.z = quat[2]
goal_pose1.pose.orientation.w = quat[3]
goal_poses.append(goal_pose1)

goal_pose2 = PoseStamped()
goal_pose2.header.frame_id = 'map'
goal_pose2.header.stamp = navigator.get_clock().now().to_msg()
goal_pose2.pose.position.x = 0.3
goal_pose2.pose.position.y = -0.2
yaw=0
quat=tf_transformations.quaternion_from_euler(0,0,yaw)
goal_pose2.pose.orientation.x = quat[0]
goal_pose2.pose.orientation.y = quat[1]
goal_pose2.pose.orientation.z = quat[2]
goal_pose2.pose.orientation.w = quat[3]
goal_poses.append(goal_pose2)

goal_pose3 = PoseStamped()
goal_pose3.header.frame_id = 'map'
goal_pose3.header.stamp = navigator.get_clock().now().to_msg()
goal_pose3.pose.position.x = -0.8
goal_pose3.pose.position.y = -0.3
yaw=0
quat=tf_transformations.quaternion_from_euler(0,0,yaw)
goal_pose3.pose.orientation.x = quat[0]
goal_pose3.pose.orientation.y = quat[1]
goal_pose3.pose.orientation.z = quat[2]
goal_pose3.pose.orientation.w = quat[3]
goal_poses.append(goal_pose3)


nav_start = navigator.get_clock().now()
navigator.followWaypoints(goal_poses)