Better defence, goalie and supporter positions by ayin21 · Pull Request #925 · bit-bots/bitbots_main

ayin21 · 2026-06-19T21:32:25Z

TBD, small proof of concept:

Checklist

jaagut · 2026-06-20T07:47:48Z

How did you get this image?

Flova · 2026-06-20T08:46:55Z

I vibe coded a simple GUI to interactively test the function that generates the placement.

This is the script I added in this pr. It is not ready yet.

…ngle robot that plays as striker)

…our)

Flova · 2026-06-23T16:11:24Z

+            width=parameters["field.size.y"],
+            goal_width=parameters["field.goal.width"],
+        )
+        self._params = Params()


Ideally we want to load theses parameters from the behavior config file (or a separate one, as the current one is pretty large as it is).

Flova · 2026-06-23T16:14:21Z

+
+        roles = []
+        if n >= 1:
+            roles.append("striker")


We might want to use a proper enum instead of strings

Flova · 2026-06-23T16:23:42Z

+
+    @cached_capsule_function
+    def get_formation_assignment(self) -> dict:
+        ballPose = self._blackboard.world_model.get_best_ball_point_stamped()


Maybe we should have separate functions for the team ball and "own ball" detection. Because we definitely want to use the team ball here.

Flova · 2026-06-23T16:36:10Z

                poses.append(data.robot_position.pose)
        return poses

+    def quaternion_to_yaw(self, q) -> float:


Specify the quaternion notation xyzw vs wxyz and maybe move/check but it's utils for these functions.

Flova · 2026-06-23T18:58:52Z

-                FIRST --> @ChangeAction + action:positioning, @LookAtFieldFeatures, @AvoidBallActive, @GoToDefensePosition + mode:freekick_first
-                SECOND --> @ChangeAction + action:positioning, @LookAtFieldFeatures, @AvoidBallActive, @GoToDefensePosition + mode:freekick_second
-                THIRD --> @ChangeAction + action:positioning, @LookAtFieldFeatures, @AvoidBallActive, @GoToDefensePosition
+            YES --> $RankToBallWithGoalie


I don't think this selection is necessary anymore. Everyone should just go to their placement position and stand there if it was reached.

i will take a closer look there once we have discussed how to handle set play situations with the new positioning capsule, got a view ideas there

Flova · 2026-06-23T18:59:59Z

Only the striker should search the ball. The others should go to the role position.

Flova · 2026-06-23T19:03:08Z

-                    FIRST --> #StrikerRole
-                    SECOND --> #SupporterRole
-                    THIRD --> #DefensePositioning
+        YES --> $RankToBallWithGoalie


I think the only really useful destinction here is striker, supporter, defender, goalie (maybe). We can probably do the same placement strategy for the goalie and and defenders and we are not limited in the number of defenders that way.

The striker needs special handling because it wants to kick if it reached its goal position. The supporter wants to track the ball if the striker is kicking and needs special handling for that and the others just go to their positions to stand in the way.

Flova · 2026-06-23T19:09:28Z

-                    SECOND --> #SupporterRole
-                    THIRD --> #DefensePositioning
+        YES --> $RankToBallWithGoalie
+            STRIKER --> #StrikerRole


The striker role needs to be reworked to position itself using the new striker placement.

Flova · 2026-06-23T21:16:24Z

Also adapt the capsule/ gui so we can do headless tests of the placement function without the software stack. Currently the function is duplicated.

Also probably some denouncing/hysteresis is needed. I would add it to the capsule as this needs to be global state. Just store if we have changed our role in the last x seconds and if did we want to stick with it. This prevents flickering behavior. The x can be randomly selected from a configurable range (0-1 sec for example).