測試Gazebo 和 ROS 2 通信時報錯

測試Gazebo 和 ROS 2 通信時報錯：

~ » gazebo --verbose /opt/ros/dashing/share/gazebo_plugins/worlds/gazebo_ros_diff_drive_demo.world                                                                                                john@john-pc
Gazebo multi-robot simulator, version 11.0.0
Copyright (C) 2012 Open Source Robotics Foundation.
Released under the Apache 2 License.
http://gazebosim.org

[Msg] Waiting for master.
Gazebo multi-robot simulator, version 11.0.0
Copyright (C) 2012 Open Source Robotics Foundation.
Released under the Apache 2 License.
http://gazebosim.org

[Msg] Waiting for master.
[Msg] Connected to gazebo master @ http://127.0.0.1:11345
[Msg] Publicized address: 192.168.2.101
[libprotobuf ERROR google/protobuf/descriptor_database.cc:57] File already exists in database: ignition/msgs/time.proto
[libprotobuf FATAL google/protobuf/descriptor.cc:1164] CHECK failed: generated_database_->Add(encoded_file_descriptor, size): 
terminate called after throwing an instance of 'google::protobuf::FatalException'
  what():  CHECK failed: generated_database_->Add(encoded_file_descriptor, size): 

解決辦法：

將gazebo11換成gazebo9就好使了