Get inflation layer parameters from node params

nav2_mppi_controller/README.md

@@ -101,6 +101,8 @@ This process is then repeated a number of times and returns a converged solution
  | collision_cost       | double | Default 10000.0. Cost to apply to a true collision in a trajectory.                                          |
  | collision_margin_distance   | double    | Default 0.10. Margin distance from collision to apply severe penalty, similar to footprint inflation. Between 0.05-0.2 is reasonable. |
  | near_goal_distance          | double    | Default 0.5. Distance near goal to stop applying preferential obstacle term to allow robot to smoothly converge to goal pose in close proximity to obstacles.   
+ | cost_scaling_factor       | double    | Default 10.0. Exponential decay factor across inflation radius. This should be the same as for your inflation layer (Humble only)
+ | inflation_radius          | double    | Default 0.55. Radius to inflate costmap around lethal obstacles. This should be the same as for your inflation layer (Humble only)
 
 #### Path Align Critic
  | Parameter                  | Type   | Definition                                                                                                                         |

nav2_mppi_controller/src/critics/obstacles_critic.cpp

@@ -58,8 +58,9 @@ double ObstaclesCritic::findCircumscribedCost(
     const double circum_radius = costmap->getLayeredCostmap()->getCircumscribedRadius();
     const double resolution = costmap->getCostmap()->getResolution();
     result = inflation_layer->computeCost(circum_radius / resolution);
-    inflation_scale_factor_ = static_cast<float>(inflation_layer->getCostScalingFactor());
-    inflation_radius_ = static_cast<float>(inflation_layer->getInflationRadius());
+    auto getParam = parameters_handler_->getParamGetter(name_);
+    getParam(inflation_scale_factor_, "cost_scaling_factor", 10.0);
+    getParam(inflation_radius_, "inflation_radius", 0.55);
   }
 
   if (!inflation_layer_found) {