UE4 logTemp Error : Joint [base_footprint_joint](and other urdf joints) is not a hinged joint with DOF=1

[JadeCong]

Hello, there is a problem when I run the PR2 simulation in UE4 with the plugin URoboSim and UROSBrigde. ROS package pr2_kinetic_packages has been configured in Ubuntu and run as well, and PR2 model tree has been created in UE4. Then I run the UE4 code RoboCoG(ex-ros-tf-robosim) and teleoperate the PR2 through keyboard in ROS, but the error occurs in UE4: LogTemp: Error: Joint [base_footprint_joint] is not a hinged joint with DOF=1; Joint [base_bellow_joint] is not a hinged joint with DOF=1 and etc...... and PR2 robot never moves but tingles freely in UE4. So what's the problem? I'm not sure whether the URoboSim plugin don't parse the urdf file and create the right model tree. Could someone who really know it give some advices?