[JTC] Add Parameter to Toggle State Setting on Activation

doc/release_notes.rst

@@ -48,6 +48,8 @@ joint_trajectory_controller
      * -1 - The tolerance is "erased".  If there was a default, the joint will be
             allowed to move without restriction.
 
+* Add the boolean parameter ``set_last_command_interface_value_as_state_on_activation``. When set to ``true``, the last command interface value is used as both the current state and the last commanded state upon activation. When set to ``false``, the current state is used for both (`#1231 <https://github.com/ros-controls/ros2_controllers/pull/1231>`_).
+
 pid_controller
 ************************
 * 🚀 The PID controller was added 🎉 (`#434 <https://github.com/ros-controls/ros2_controllers/pull/434>`_).

joint_trajectory_controller/src/joint_trajectory_controller.cpp

@@ -924,7 +924,9 @@ controller_interface::CallbackReturn JointTrajectoryController::on_activate(
   // running already)
   trajectory_msgs::msg::JointTrajectoryPoint state;
   resize_joint_trajectory_point(state, dof_);
-  if (read_state_from_command_interfaces(state))
+  if (
+    params_.set_last_command_interface_value_as_state_on_activation &&
+    read_state_from_command_interfaces(state))
   {
     state_current_ = state;
     last_commanded_state_ = state;

joint_trajectory_controller/src/joint_trajectory_controller_parameters.yaml

@@ -64,6 +64,11 @@ joint_trajectory_controller:
     default_value: false,
     description: "Allow integration in goal trajectories to accept goals without position or velocity specified",
   }
+  set_last_command_interface_value_as_state_on_activation: {
+    type: bool,
+    default_value: true,
+    description: "When set to true, the last command interface value is used as both the current state and the last commanded state upon activation. When set to false, the current state is used for both.",
+  }
   action_monitor_rate: {
     type: double,
     default_value: 20.0,