improve h2.5 parameters changelog

Author: Alberto Soragna

docs/releases/h_2_5.md

@@ -26,23 +26,36 @@ See below for details.
 * Library Versions
     * Update Cyclone DDS from 0.9.0 to 0.10.3
 * Parameters
-    * Add parameter `/motion_control wheels_stop_threshold_sec`
-    * Add the following ROS 2 parameters to control (and disable) unnecessary ROS 2 publications to improve robot performance:
-        * `publish_hazard_msgs`: default `true`. If set to false, the robot will not publish the `/hazard_detection` topic. This can noticeably reduce the CPU and RAM usage of the robot.
-        * `hazards_pub_fixed_period_ms`: default `15`. This controls whether the robot should publish hazard information even if the hazards are not changing. Set it to `-1` to disable fixed period hazard publications and have hazards be published only when they change. This parameter will be ignored if `publish_hazard_msgs` is set to `false`.
-        * `raw_kinematics_min_pub_period_ms`: default `1`. This controls the minimum period at which the robot should publish raw kinematics information. If set to `-1`, it will disable raw kinematics publications. This can noticeably reduce the CPU and RAM usage of the robot. Values higher than `1` can still give some CPU improvement, but won't help RAM usage.
-        * `publish_odom_tfs`: default `true`. If set to false, the robot will not publish odometry information in the `/tf` topic. This can reduce the CPU and RAM usage of the robot if not needed. Note: this parameter is not related to `raw_kinematics_min_pub_period_ms`
+    * Add ROS 2 parameter `wheels_stop_threshold_sec` to the `/motion_control` node. This parameter controls the amount of time that the robot will keep executing the last provided velocity command (on the `/cmd_vel` topic) before considering it stale and stopping the wheels. Default value is 0.5 seconds.
+    * Add the following ROS 2 parameters to the `/robot_state` node to control (and disable) unnecessary ROS 2 publications to improve robot performance:
+        * `publish_hazard_msgs`: default `true`. If set to false, the robot will not publish the `/hazard_detection` topic. Disabling this can noticeably reduce the CPU and RAM usage of the robot.
+        * `hazards_pub_fixed_period_ms`: default `-1`. This controls whether the robot should publish hazard information even if the hazards are not changing. Set it to `-1` to disable fixed period hazard publications and have hazards be published only when they change. This parameter will be ignored if `publish_hazard_msgs` is set to `false`.
+        * `raw_kinematics_min_pub_period_ms`: default `25`. This controls the minimum period at which the robot should publish raw kinematics information. If set to `-1`, it will disable raw kinematics publications. This can noticeably reduce the CPU and RAM usage of the robot. A value of `1` indicates that raw data should be published as soon as they are available. Values higher than `1` will throttle publications and will give some CPU improvement, but won't help RAM usage.
+        The following topics are affected by this parameter: `/imu`, `/mouse`, `/wheel_status`, `/wheel_ticks`,  `/wheel_vels`.
+        If you are not interested in subscribing to these topics, it's recommended to set this parameter's value to `-1`.
+        * `publish_odom_tfs`: default `true`. If set to false, the robot will not publish odometry information in the `/tf` topic. This can reduce the CPU and RAM usage of the robot if not needed. Note: this parameter is independent from `raw_kinematics_min_pub_period_ms`
 
         As a summary, the best performance can be obtained via
         ```
         robot_state:
-        ros__parameters:
+          ros__parameters:
             publish_hazard_msgs: false
             publish_odom_tfs: false
             raw_kinematics_min_pub_period_ms: -1
         ```
 
         Note that `publish_odom_tfs: true` is required to interact with the navigation stack.
+    
+        This new version changes the default timing of some ROS 2 topics to improve the CPU performance.
+        To restore the previous behavior users can use the following configuration
+
+        ```
+        robot_state:
+          ros__parameters:
+            hazards_pub_fixed_period_ms: 16
+            raw_kinematics_min_pub_period_ms: 1
+        ```
+
 
 [^1]: ROS 2 is governed by Open Robotics.
 [^2]: The Bluetooth® word mark and logos are registered trademarks owned by Bluetooth SIG, Inc. and any use of such marks by iRobot is under license.