Multiple Robots in Simulation with Namespace Environment Variable

Hi, I want to simulate multiple robots in gazebo and started with namespace settings. I'm running running this command before launching `mrp2_gazebo.launch` : ~$ export ROS_NAMESPACE=robot1 It works on other nodes: process[robot1/gazebo-2]: started with pid [27341] process[robot1/gazebo_gui-3]: started with pid [27345] process[robot1/robot_state_publisher-4]: started with pid [27349] process[robot1/spawn_model_ubuntu_ogh_huma_27289_1249120356262851661-5]: started with pid [27350] process[robot1/controller_spawner-6]: started with pid [27351] process[robot1/ekf_localization-7]: started with pid [27357] process[robot1/twist_mux-8]: started with pid [27364] process[robot1/twist_marker-9]: started with pid [27366] process[robot1/joystick_relay-10]: started with pid [27378] process[robot1/joy_teleop-11]: started with pid [27383] process[robot1/joystick-12]: started with pid [27385] process[robot1/twist_marker_server-13]: started with pid [27388] process[robot1/mrp2_diag_publisher-14]: started with pid [27394] process[robot1/diagnostic_aggregator-15]: started with pid [27401] but Controller Spawner couldn't find controller_manager ROS interface: [INFO] [WallTime: 1462190862.012295] [0.000000] Controller Spawner: Waiting for service controller_manager/load_controller and; [WARN] [WallTime: 1462189886.211852] [209.507000] Controller Spawner couldn't find the expected controller_manager ROS interface. `~$ rosservice list | grep controller_manager` returns nothing. Here is my `controls.launch` file (working without namespace variable): `gazebo.urdf.xacro`'s plugin lines: robot1mrp2_hardware_gazebo/Mrp2HardwareGazebo0.001 Thanks!