Robot_localization IMU frame tf

Im running a simulation in Gazebo combining the odomery data (coming from the differential drive plugin) and the imu data (from GazeboRosImuSensor plugin). Im quite new to ROS and im totally confused with the ENU and NED frames .. This is what I did 1)placed the IMU in its neutral position 2)setup a static transform broadcaster which broadcasts my base_link to odom frame here i made the rotation. this is the code snippet in my launch file I have rolled it by 180 and yaw by 90 I tested the IMU and it shows correct accelerations as shown (http://docs.ros.org/lunar/api/robot_localization/html/preparing_sensor_data.html) But when i visualise my odometrydatas, the unfiltered odometry data(from diffdrive plugin) and the filtered odometry data(from robot_localization) are in opposite orientation. This happens only when include my imu as an input to the robot_localization package.