diff --git a/Runtime/Scripts/ROS/Unity/Publishers/ZOROSIMUPublisher.cs b/Runtime/Scripts/ROS/Unity/Publishers/ZOROSIMUPublisher.cs
index ae6318e..b2422b0 100644
--- a/Runtime/Scripts/ROS/Unity/Publishers/ZOROSIMUPublisher.cs
+++ b/Runtime/Scripts/ROS/Unity/Publishers/ZOROSIMUPublisher.cs
@@ -29,7 +29,7 @@ public ZOIMU IMUSensor {
         }
 
         public enum CoordinateSystemEnum {
-            RightHanded_XBackward_YLeft_ZUp,
+            RightHanded_XBackward_YLeft_ZDown,
             RightHanded_XRight_YDown_ZForward,       // RealSense D435i
             Unity_LeftHanded_XRight_YUp_ZForward,   // Unity Standard
             ROS_RightHanded_XForward_YLeft_ZUp,                 // ROS Standard
@@ -128,7 +128,7 @@ private Task OnPublishImuDelegate(ZOIMU lidar, string name, Vector3 linearAccel,
                 _imuMessage.angular_velocity.UnityVector3 = angularVelocity;
                 _imuMessage.orientation.UnityQuaternion = orientation;
 
-            } else if (CoordinateSystem == CoordinateSystemEnum.RightHanded_XBackward_YLeft_ZUp) {
+            } else if (CoordinateSystem == CoordinateSystemEnum.RightHanded_XBackward_YLeft_ZDown) {
                 //  (x, y, z, w) -> (-x, -z, y, -w).
                 _imuMessage.orientation.x = -orientation.z;
                 _imuMessage.orientation.y = -orientation.x;
@@ -137,11 +137,11 @@ private Task OnPublishImuDelegate(ZOIMU lidar, string name, Vector3 linearAccel,
 
                 _imuMessage.linear_acceleration.x = -linearAccel.z + -gravity.z;
                 _imuMessage.linear_acceleration.y = -linearAccel.x + -gravity.x;
-                _imuMessage.linear_acceleration.z = linearAccel.y + gravity.y;
+                _imuMessage.linear_acceleration.z = -linearAccel.y - gravity.y;
 
                 _imuMessage.angular_velocity.x = -angularVelocity.z;
                 _imuMessage.angular_velocity.y = -angularVelocity.x;
-                _imuMessage.angular_velocity.z = angularVelocity.y;
+                _imuMessage.angular_velocity.z = -angularVelocity.y;
             } else if (CoordinateSystem == CoordinateSystemEnum.RightHanded_XRight_YDown_ZForward) { // aka RealSense
                 Quaternion flippedYOrientation = Quaternion.Euler(Vector3.Scale(orientation.eulerAngles, Vector3.up * -1));
                 _imuMessage.orientation.x = flippedYOrientation.x;