add README

Signed-off-by: Kyoichi Sugahara <[email protected]>

planning/autoware_planning_validator/README.md

@@ -85,5 +85,10 @@ The input trajectory is detected as invalid if the index exceeds the following t
 
 For parameters used e.g. to calculate threshold.
 
-| `parameters.forward_trajectory_length_acceleration` | double | This value is used to calculate required trajectory length. | -5.0 |
-| `parameters.forward_trajectory_length_margin` | double | A margin of the required trajectory length not to raise an error when the ego slightly exceeds the trajectory end point. | 2.0 |
+| Parameter Name                                       | Type   | Description                                                                                                                                                                                                                                                        | Default Value |
+| ---------------------------------------------------- | ------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------- |
+| `parameters.forward_trajectory_length_acceleration`  | double | This value is used to calculate required trajectory length.                                                                                                                                                                                                        | -5.0          |
+| `parameters.forward_trajectory_length_margin`        | double | A margin of the required trajectory length not to raise an error when the ego slightly exceeds the trajectory end point.                                                                                                                                           | 2.0           |
+| `parameters.trajectory_to_object_distance_threshold` | double | A threshold for filtering objects to improve computational efficiency of collision checking. Only objects within this distance [m] from their nearest point on the trajectory are considered for collision checking.                                               | 30.0          |
+| `parameters.ego_to_object_distance_threshold`        | double | A threshold for filtering objects to improve computational efficiency of collision checking. Only objects within this distance [m] from the current ego position are considered for collision checking.                                                            | 50.0          |
+| `parameters.time_tolerance_threshold`                | double | Time tolerance threshold [s] for collision detection between ego and object trajectories. Collision check is performed only when the time difference between ego and object predicted positions is within this threshold to detect temporal-spatial intersections. | 0.1           |