Hi everybody I am new here. I have just installed gazebo-tools and pr2-gazebo as per instructions on web site and when i tried to run empty world I got this error: ODE Message 2: inertia must be positive definite in dMassCheck() File mass.cpp Line 53 Error Loading Gazebo /home/tingting/ros/stacks/simulator_gazebo/gazebo/gazebo-svn/server/Simulator.cc:240 : Exception: Failed to load the World /home/tingting/ros/stacks/simulator_gazebo/gazebo/gazebo-svn/server/controllers/ControllerFactory.cc:116 : Exception: Failed to load libgazebo_ros_time.so: file not found I have no idea where can i find libgazebo_ros_time.so and where should i put it any help will be great. thanks Amy