Backport changes from #623

Author: christophfroehlich

example_7/reference_generator/send_trajectory.cpp

@@ -96,6 +96,15 @@ int main(int argc, char ** argv)
     trajectory_msg.points.push_back(trajectory_point_msg);
   }
 
+  // send zero velocities in the end
+  std::fill(trajectory_point_msg.velocities.begin(), trajectory_point_msg.velocities.end(), 0.0);
+  trajectory_point_msg.time_from_start.sec = trajectory_len / loop_rate;
+  trajectory_point_msg.time_from_start.nanosec = static_cast<int>(
+    1E9 / loop_rate *
+    static_cast<double>(
+      trajectory_len - loop_rate * (trajectory_len / loop_rate)));  // implicit integer division
+  trajectory_msg.points.push_back(trajectory_point_msg);
+
   pub->publish(trajectory_msg);
   while (rclcpp::ok())
   {