no messages received in topic after transformation

edit

Hello,

we are driving a vehicle with GPS and automated path planning and I recorded the drives. The rosbag is playing great, but I wanted to visualize the driven path to check the accuracy.

I tried something else but then thought it would work good enough with tracking odometry in RVIZ. I thought using the gps signal would be the best and I have a topic /odometry/gps which is a PoseStamped. To visualize it in RVIZ, I wanted to transform it into a /odometry message, which I could then show in RVIZ. I use this script for it:

import rospy
from geometry_msgs.msg import PoseStamped, Quaternion
from nav_msgs.msg import Odometry
from tf.transformations import quaternion_from_euler, euler_from_quaternion


class OdomPub:
def __init__(self):
        self.odom = Odometry()
        self.odometry_pub = rospy.Publisher('/odometry', Odometry, queue_size=1)
    rospy.Subscriber("/odometry/gps", PoseStamped, self.pose_callback)

      def rotate_quaternion(self):
            # TS 2021_07_26: the heading is measured from antenna 1 (front) to antenna 2 (back) and thus mirrored over origin 
            quat = [self.odom.pose.orientation.x, self.odom.pose.orientation.y, self.odom.pose.orientation.z, self.odom.pose.orientation.w]
            (alpha,beta,gamma) = euler_from_quaternion(quat, axes='sxyz')

            self.odom.orientation.quaternion = Quaternion(*quaternion_from_euler(alpha, beta, -gamma))

        def publish_heading(self):
            self.odometry_pub.publish(self.odom)

        def pose_callback (self, pose):
            self.odom.header = pose.header
            self.odom.pose = pose.pose
            self.odom.child_frame_id = "base_link"

            #self.rotate_quaternion()  

if __name__ == '__main__':
        #print('something started')
        rospy.init_node('trajectory_pub')
        OdomPub()
        rospy.spin() here

Here is my problem: I get the topic published with no warnings left, BUT when I echo the /odometry, I get the followiing

 rostopic echo /odometry 
    WARNING: no messages received and simulated time  is active. 
    Is /clock being published?

of course /clock is active, because i play rosbag with clock.

So again: on /odometry/gps (which is the PoseStamped) I get a good gps signal, but still not on the /odometry (Odometry) topic.

edit: I added some lines to call the publish_heading and I get no errors, but still doesn't work.

if __name__ == '__main__': print('something started') odom_pub=OdomPub() rospy.init_node('trajectory_pub') odom_pub.publish_heading() OdomPub() rospy.spin()

Here is the launch file. <launch>

    <!--  ************** Global Parameters ***************  -->
  <param name="/use_sim_time" value="true"/>


    <arg name="target_x_vel" default="2.3"/>
    <arg name="target_yaw_vel" default="0.8"/>
    <arg name="robot_radius" default="0.6"/>
    <arg name="tool_radius" default="0.6"/>   

  <node pkg="tf" type="static_transform_publisher" name="odom_tf_publisher" args="0 0 0 0 0 0 1 map odom 100" />
  <node pkg="tf" type="static_transform_publisher" name="utm_to_map_tf_publisher" args="361282.288 5814827.341 0 0 0 1 utm map 100" />
  <node name="OdomPub" pkg="gps_localization" type="PoseStamped_to_odometry.py"/>


    <!--  ************** Navigation ***************  -->
<node pkg="move_base" type="move_base" respawn="false" name="move_base" output="screen">

  <rosparam file="$(find teb_local_planner_tutorials)/cfg/carlike/costmap_common_params.yaml" command="load" ns="global_costmap" />
    <rosparam file="$(find teb_local_planner_tutorials)/cfg/carlike/costmap_common_params.yaml" command="load" ns="local_costmap" />
    <rosparam file="$(find teb_local_planner_tutorials)/cfg/carlike/local_costmap_params.yaml" command="load" />
    <rosparam file="$(find teb_local_planner_tutorials)/cfg/carlike/global_costmap_params ...