adding readme

nav2_smac_planner/README.md

@@ -115,6 +115,8 @@ planner_server:
       angle_quantization_bins: 64         # For Hybrid nodes: Number of angle bins for search, must be 1 for 2D node (no angle search)
       analytic_expansion_ratio: 3.5       # For Hybrid/Lattice nodes: The ratio to attempt analytic expansions during search for final approach.
       analytic_expansion_max_length: 3.0    # For Hybrid/Lattice nodes: The maximum length of the analytic expansion to be considered valid to prevent unsafe shortcutting (in meters). This should be scaled with minimum turning radius and be no less than 4-5x the minimum radius
+      analytic_expansion_max_cost: true   # For Hybrid/Lattice nodes: The maximum single cost for any part of an analytic expansion to contain and be valid (except when necessary on approach to goal)
+      analytic_expansion_max_cost_override: false  #  For Hybrid/Lattice nodes: Whether or not to override the maximum cost setting if within critical distance to goal (ie probably required)
       minimum_turning_radius: 0.40        # For Hybrid/Lattice nodes: minimum turning radius in m of path / vehicle
       reverse_penalty: 2.1                # For Reeds-Shepp model: penalty to apply if motion is reversing, must be => 1
       change_penalty: 0.0                 # For Hybrid nodes: penalty to apply if motion is changing directions, must be >= 0