Change robot speed at runtime

Signed-off-by: Francisco Martin Rico <fmrico@gmail.com>

nav2_dwb_controller/dwb_plugins/include/dwb_plugins/kinematic_parameters.hpp

@@ -113,6 +113,11 @@ protected:
   double max_speed_xy_sq_{0};
 
   void reconfigureCB();
+  
+  // Subscription for parameter change
+  rclcpp::AsyncParametersClient::SharedPtr parameters_client_;
+  rclcpp::Subscription<rcl_interfaces::msg::ParameterEvent>::SharedPtr parameter_event_sub_;
+  void on_parameter_event_callback(const rcl_interfaces::msg::ParameterEvent::SharedPtr event);
 };
 
 }  // namespace dwb_plugins

nav2_dwb_controller/dwb_plugins/src/kinematic_parameters.cpp

@@ -48,6 +48,8 @@ using nav_2d_utils::moveDeprecatedParameter;
 namespace dwb_plugins
 {
 
+using std::placeholders::_1;
+
 KinematicParameters::KinematicParameters()
 {
 }
@@ -90,6 +92,16 @@ void KinematicParameters::initialize(const nav2_util::LifecycleNode::SharedPtr &
   nh->get_parameter("decel_lim_y", decel_lim_y_);
   nh->get_parameter("decel_lim_theta", decel_lim_theta_);
 
+  // Setup callback for changes to parameters.
+  parameters_client_ = std::make_shared<rclcpp::AsyncParametersClient>(
+    nh->get_node_base_interface(),
+    nh->get_node_topics_interface(),
+    nh->get_node_graph_interface(),
+    nh->get_node_services_interface());
+
+  parameter_event_sub_ = parameters_client_->on_parameter_event(
+    std::bind(&KinematicParameters::on_parameter_event_callback, this, _1));
+
   min_speed_xy_sq_ = min_speed_xy_ * min_speed_xy_;
   max_speed_xy_sq_ = max_speed_xy_ * max_speed_xy_;
 }
@@ -104,4 +116,49 @@ bool KinematicParameters::isValidSpeed(double x, double y, double theta)
   return true;
 }
 
+void
+KinematicParameters::on_parameter_event_callback(
+  const rcl_interfaces::msg::ParameterEvent::SharedPtr event)
+{
+  using namespace rcl_interfaces::msg;
+
+  for (auto & changed_parameter : event->changed_parameters) {
+    const auto & type = changed_parameter.value.type;
+    const auto & name = changed_parameter.name;
+    const auto & value = changed_parameter.value;
+
+    if (type == ParameterType::PARAMETER_DOUBLE) {
+      if (name == "min_vel_x") {
+        min_vel_x_ = value.double_value;
+      } else if (name == "min_vel_y") {
+        min_vel_y_ = value.double_value;
+      } else if (name == "max_vel_x") {
+        max_vel_x_ = value.double_value;
+      } else if (name == "max_vel_y") {
+        max_vel_y_ = value.double_value;
+      } else if (name == "max_vel_theta") {
+        max_vel_theta_ = value.double_value;
+      } else if (name == "min_speed_xy") {
+        min_speed_xy_ = value.double_value;
+      } else if (name == "max_speed_xy") {
+        max_speed_xy_ = value.double_value;
+      } else if (name == "min_speed_theta") {
+        min_speed_theta_ = value.double_value;
+      } else if (name == "acc_lim_x") {
+        acc_lim_x_ = value.double_value;
+      } else if (name == "acc_lim_y") {
+        acc_lim_y_ = value.double_value;
+      } else if (name == "acc_lim_theta") {
+        acc_lim_theta_ = value.double_value;
+      } else if (name == "decel_lim_x") {
+        decel_lim_x_ = value.double_value;
+      } else if (name == "decel_lim_y") {
+        decel_lim_y_ = value.double_value;
+      } else if (name == "decel_lim_theta") {
+        decel_lim_theta_ = value.double_value;
+      }
+    }
+  }
+}
+
 }  // namespace dwb_plugins