Set smaller timeout for service node

nav2_behavior_tree/include/nav2_behavior_tree/bt_service_node.hpp

@@ -57,14 +57,17 @@ class BtServiceNode : public BT::ActionNodeBase
     callback_group_executor_.add_callback_group(callback_group_, node_->get_node_base_interface());
 
     // Get the required items from the blackboard
-    bt_loop_duration_ =
+    max_timeout_ =
       config().blackboard->template get<std::chrono::milliseconds>("bt_loop_duration");
     server_timeout_ =
       config().blackboard->template get<std::chrono::milliseconds>("server_timeout");
     getInput<std::chrono::milliseconds>("server_timeout", server_timeout_);
     wait_for_service_timeout_ =
       config().blackboard->template get<std::chrono::milliseconds>("wait_for_service_timeout");
 
+    // timeout should be less than bt_loop_duration to be able to finish the current tick
+    max_timeout_ *= 0.5;
+
     // Now that we have node_ to use, create the service client for this BT service
     getInput("service_name", service_name_);
     service_client_ = node_->create_client<ServiceT>(
@@ -189,7 +192,7 @@ class BtServiceNode : public BT::ActionNodeBase
     auto remaining = server_timeout_ - elapsed;
 
     if (remaining > std::chrono::milliseconds(0)) {
-      auto timeout = remaining > bt_loop_duration_ ? bt_loop_duration_ : remaining;
+      auto timeout = remaining > max_timeout_ ? max_timeout_ : remaining;
 
       rclcpp::FutureReturnCode rc;
       rc = callback_group_executor_.spin_until_future_complete(future_result_, timeout);
@@ -249,7 +252,7 @@ class BtServiceNode : public BT::ActionNodeBase
   std::chrono::milliseconds server_timeout_;
 
   // The timeout value for BT loop execution
-  std::chrono::milliseconds bt_loop_duration_;
+  std::chrono::milliseconds max_timeout_;
 
   // The timeout value for waiting for a service to response
   std::chrono::milliseconds wait_for_service_timeout_;