Reviewing files that changed from the base of the PR and between e949a6d and 0513e83.

• build/agent_service.yaml (0 hunks)
• code/acting/src/acting/passthrough.py (2 hunks)
• code/control/src/vehicle_controller.py (1 hunks)
• code/control/src/velocity_controller.py (1 hunks)
• code/mapping/ext_modules/mapping_common/map.py (1 hunks)
• code/perception/CMakeLists.txt (2 hunks)
• code/perception/msg/LaneChange.msg (1 hunks)
• code/perception/src/global_plan_distance_publisher.py (4 hunks)
• code/planning/src/behavior_agent/behavior_tree.py (2 hunks)
• code/planning/src/behavior_agent/behaviors/behavior_speed.py (1 hunks)
• code/planning/src/behavior_agent/behaviors/lane_change.py (5 hunks)
• code/planning/src/behavior_agent/behaviors/overtake.py (3 hunks)
• code/planning/src/behavior_agent/behaviors/overtake_service_utils.py (1 hunks)
• code/planning/src/behavior_agent/behaviors/topics2blackboard.py (1 hunks)
• code/planning/src/behavior_agent/behaviors/unstuck_routine.py (5 hunks)
• code/planning/src/local_planner/utils.py (1 hunks)
• doc/general/architecture_current.md (3 hunks)
• doc/general/architecture_planned.md (1 hunks)
• doc/planning/motion_planning.md (1 hunks)

• build/agent_service.yaml

• code/planning/src/behavior_agent/behaviors/overtake_service_utils.py
• doc/general/architecture_planned.md

code/perception/msg/LaneChange.msg (1)

4-4: Good addition of spatial information to enhance lane change messages.

The addition of the position field using geometry_msgs/Point type enhances the message by providing explicit spatial coordinates for the lane change point. This is a logical extension that complements the existing distance field, enabling more precise navigation during lane changes.

code/mapping/ext_modules/mapping_common/map.py (1)

36-39:

✅ Verification successful

Well-structured enum for lane change direction.

The newly added LaneFreeDirection enum provides clear semantics for lane change directions with properly named constants (LEFT and RIGHT). This improves code readability and maintains consistency throughout lane change operations.

One thing to verify: ensure that the boolean mapping (LEFT=False, RIGHT=True) is used consistently throughout the codebase to prevent potential confusion.

---

🏁 Script executed:

#!/bin/bash
# Search for usages of LaneFreeDirection to ensure consistent usage
rg "LaneFreeDirection\.(LEFT|RIGHT)" -A 2 -B 2

Length of output: 3175

---

Enum Mapping for LaneFreeDirection Verified and Consistent

The LaneFreeDirection enum defined as:

class LaneFreeDirection(Enum):
    LEFT = False
    RIGHT = True

provides clear semantics and aligns with the intended boolean mapping. A repository-wide search confirmed that the enum is used consistently in the lane change logic (e.g., in code/planning/src/behavior_agent/behaviors/lane_change.py).

Approved.

doc/planning/motion_planning.md (1)

38-38: Topic name updated correctly in documentation.

The topic name has been updated from /paf/hero/lane_change_distance to /paf/hero/lane_change to reflect the changes made throughout the codebase. This maintains consistency between the implementation and documentation.

🧰 Tools

🪛 LanguageTool

[uncategorized] ~38-~38: Loose punctuation mark.
Context: ...rent waypoint. - /paf/hero/lane_change: Subscribes to the Carla Waypoint to che...

(UNLIKELY_OPENING_PUNCTUATION)

code/planning/src/behavior_agent/behaviors/behavior_speed.py (1)

60-60:

✅ Verification successful

Appropriate addition of new lane change behavior state.

The new lc_wait_free behavior with a non-zero speed (30 km/h) complements the existing lc_wait behavior (0 speed). This appears to support the implementation of lane-free checks, allowing the vehicle to proceed at a moderate speed when the target lane is free rather than coming to a complete stop.

Note that according to the file header comments, the speed values in this file are deprecated and "completely unused in favor of the ACC" since PR #725. Verify that the behavior name itself is being properly utilized in the lane change implementation.

---

🏁 Script executed:

#!/bin/bash
# Search for usages of the new behavior name to ensure it's being used appropriately
rg "lc_wait_free" --type py

Length of output: 276

---

Verification complete: "lc_wait_free" behavior is correctly integrated.

We confirmed that the new behavior is actively used within the lane change implementation (refer to the publish call in code/planning/src/behavior_agent/behaviors/lane_change.py). The utilization aligns with the intended design despite the deprecation of speed values per the header comments.

code/control/src/vehicle_controller.py (1)

156-159:

❓ Verification inconclusive

Improved steering logic for unstuck and stop behaviors

The change inverts the steering direction during unstuck and stop behaviors, which should help the vehicle maneuver more effectively in recovery situations. This is a sensible approach as it allows the vehicle to steer in the opposite direction to get out of stuck positions.

To ensure this change doesn't cause unexpected behavior, verify this in simulation with these specific scenarios:

1. Vehicle attempting to get unstuck from various positions
2. Vehicle executing stop behaviors
3. Testing that the transition between normal and unstuck/stop steering is smooth

---

🏁 Script executed:

#!/bin/bash
# Search for any existing tests for unstuck or stop behaviors
rg -A 3 -B 3 "us_unstuck|us_stop" --type py

Length of output: 3640

---

Simulation Verification Required: Confirm Unstuck & Stop Behavior Transitions

The modified steering logic (multiplying _p_steer by -1 for us_unstuck and us_stop) is implemented as intended in code/control/src/vehicle_controller.py (lines 156–159). References in related modules (e.g., in planning and behavior routines) confirm these behaviors are triggered as expected. Please ensure that simulation tests cover the following:

• Vehicle unstuck scenarios: Validate steering inversion when the vehicle is trying to recover from being stuck.
• Stop behavior: Confirm that the vehicle executes a controlled stopping behavior.
• Transition smoothness: Verify that switching between normal and recovery (unstuck/stop) steering is seamless.

doc/general/architecture_current.md (2)

126-126: Topic name update reflects the changes in code

The topic rename from lane_change_distance to lane_change is consistent with other changes in the codebase. This documentation update ensures that the architecture documentation stays accurate.

---

262-262: Topic name update in local planning section

The topic reference has been properly updated here as well, maintaining consistency across the documentation.

code/planning/src/behavior_agent/behaviors/topics2blackboard.py (1)

95-95:

❓ Verification inconclusive

Topic subscription updated to match the new topic name

This change aligns the topic subscription with the renamed topic (lane_change instead of lane_change_distance), consistent with the architectural changes throughout the codebase.

To ensure the topic rename is consistent across the entire codebase:

---

🏁 Script executed:

#!/bin/bash
# Check if there are any remaining references to the old topic name
rg "lane_change_distance" --type py

Length of output: 35

---

Action: Manually Verify Topic Name Consistency

Automated searches across Python files show no lingering references to the old topic name “lane_change_distance.” However, since the initial script produced no output, please manually verify that:

• The file code/planning/src/behavior_agent/behaviors/topics2blackboard.py (line 95) correctly uses "name": f"/paf/{role_name}/lane_change" without any residual references to “lane_change_distance.”
• There are no occurrences of “lane_change_distance” in non-Python files (e.g., configuration, documentation, tests) that might affect the rename.

Once confirmed, you can safely assume the topic update is fully consistent.

code/perception/CMakeLists.txt (2)

17-17: Added geometry_msgs dependency to support LaneChange message enhancement

The addition of geometry_msgs as a dependency is necessary to support the new position field in the LaneChange message, which allows for spatial information to be included in lane change data.

---

79-79:

✅ Verification successful

Added geometry_msgs to message generation dependencies

This correctly adds geometry_msgs to the message generation dependencies, ensuring that types from this package can be used in the LaneChange message. This change complements the addition to the find_package section above.

Verify that the LaneChange.msg file has been updated to include a position field of type geometry_msgs/Point:

---

🏁 Script executed:

#!/bin/bash
# Check the LaneChange.msg file for the position field
cat code/perception/msg/LaneChange.msg

Length of output: 120

---

Review Confirmed: Geometry_msgs Dependency and Message Field Verification

The changes correctly add the geometry_msgs dependency, and the LaneChange.msg file now includes the position field of type geometry_msgs/Point as expected.

• Verified in code/perception/msg/LaneChange.msg that the line geometry_msgs/Point position exists.
• This update complements the changes made in CMakeLists.txt and the find_package additions.

code/planning/src/behavior_agent/behavior_tree.py (1)

83-83:

✅ Verification successful

Lane change behavior has been simplified

The change from separate Enter/Leave actions to a single Change action simplifies the lane change process. This consolidation aligns with the PR objective to rework the lane change behavior.

---

🏁 Script executed:

#!/bin/bash
# Description: Check for implementation of lane_change.Change class and its usage

# Find the implementation of the Change class in lane_change.py
rg -A 10 "class Change" code/planning/src/behavior_agent/behaviors/lane_change.py

Length of output: 395

---

Validated: Lane Change Behavior Simplification

The usage of lane_change.Change("Execute Change") in the behavior tree now aligns with the intended simplified lane change process. The implementation in code/planning/src/behavior_agent/behaviors/lane_change.py confirms that the Change class is correctly defined, inheriting from py_trees.behaviour.Behaviour, which meets the PR objectives.

• File Verified: code/planning/src/behavior_agent/behaviors/lane_change.py contains the proper Change class implementation.
• Usage Confirmed: The instantiation lane_change.Change("Execute Change") in code/planning/src/behavior_agent/behavior_tree.py is correct and reflects the consolidation of lane change actions.

code/planning/src/local_planner/utils.py (2)

15-16: Improved precision with floating-point values

Converting integer values to floating-point improves precision in distance calculations, which is beneficial for vehicle control systems.

---

17-18:

❓ Verification inconclusive

New lane change distance parameters added

These new constants provide more nuanced control for lane change behaviors:

• TARGET_DISTANCE_TO_STOP_LANECHANGE: Defines when to stop during a lane change
• TARGET_DISTANCE_TO_TRIGGER_LANECHANGE: Controls when to trigger lane changes

The trigger distance of 75.0 meters seems quite large. Consider whether this distance is appropriate based on the comments in the PR about premature lane changes.

---

🏁 Script executed:

#!/bin/bash
# Description: Check where and how the new lane change constants are used

# Search for usage of TARGET_DISTANCE_TO_TRIGGER_LANECHANGE
rg "TARGET_DISTANCE_TO_TRIGGER_LANECHANGE" -A 5 code/planning/src/behavior_agent/behaviors/

# Search for usage of TARGET_DISTANCE_TO_STOP_LANECHANGE
rg "TARGET_DISTANCE_TO_STOP_LANECHANGE" -A 5 code/planning/src/behavior_agent/behaviors/

Length of output: 2630

---

Action: Revisit and confirm lane change distance parameters

The new constants are correctly integrated in the lane change behavior code (see code/planning/src/behavior_agent/behaviors/lane_change.py). Specifically:

• TARGET_DISTANCE_TO_STOP_LANECHANGE (5.0 meters) is used to determine when a lane change should stop.
• TARGET_DISTANCE_TO_TRIGGER_LANECHANGE (75.0 meters) is applied to trigger the lane change maneuver.

Based on the verification output, these constants are consistently referenced. However, the trigger distance of 75.0 meters appears relatively high compared to the stopping distance, which might be a contributing factor for premature lane changes. Please reassess this value against simulation results or defined behavioral requirements to ensure it meets the intended control strategy.

code/acting/src/acting/passthrough.py (2)

61-67: Updated mapped_topics list

The mapped_topics list is properly updated to include the new acc_to_target_velocity mapping, ensuring it's processed by the Passthrough class.

---

38-42:

✅ Verification successful

New topic mapping for acceleration velocity

This new TopicMapping creates a pass-through from /paf/{role_name}/acc_velocity to /paf/hero/target_velocity, enabling direct influence on target velocity from acceleration commands. This enhances the communication between components.

---

🏁 Script executed:

#!/bin/bash
# Description: Verify topic naming consistency across the codebase

# Check for other usages of the target_velocity topic
rg "/paf/hero/target_velocity" --glob "!code/acting/src/acting/passthrough.py"

# Check for other usages of the acc_velocity topic
rg "/paf/hero/acc_velocity" --glob "!code/acting/src/acting/passthrough.py"

Length of output: 1825

---

Validated Topic Mapping for Acceleration Velocity

The new TopicMapping in code/acting/src/acting/passthrough.py (lines 38–42) correctly creates a pass-through from /paf/{role_name}/acc_velocity to /paf/hero/target_velocity. Verification shows that:

• /paf/hero/target_velocity is used consistently across launch files, behavior routines, and documentation.
• /paf/hero/acc_velocity is referenced in planning behaviors (e.g., in leave_parking_space.py) and related documents.

This confirms that the naming and implementation are consistent with the rest of the codebase. No further changes are needed.

code/control/src/velocity_controller.py (1)

111-124: Improved handling of negative target velocities

The changes to reverse driving logic are beneficial:

1. Simplified logic by handling all negative velocities as signals for reverse driving
2. Added flexibility through PID-based throttle control when not in fixed speed mode
3. Removed hard-coded checks for specific velocity values (-3)

These changes make the code more maintainable and adaptable to different scenarios, which is helpful for the lane change behavior enhancements.

code/planning/src/behavior_agent/behaviors/overtake.py (2)

369-370: Resetting counter only if lane is blocked looks consistent.
This aligns with the idea that the counter should only reset if the oncoming lane is definitively blocked.

---

507-508: Identical reset logic in Wait class.
Mirroring the same counter reset condition when the lane is blocked helps maintain consistency between behaviors.

code/planning/src/behavior_agent/behaviors/unstuck_routine.py (4)

13-14: Additional imports look correct.
The newly imported add_speed_override, debug_status, and debug_marker appear to be used properly below.

---

16-19: Stop mark service imports are used appropriately.
These look useful for adjusting stop marks during the unstuck routine.

---

22-24: Configuration changes for stuck durations are fine.
Increasing the thresholds for stuck detection and wait seems intentional.

---

26-27: Marker color and lookup distance adjustments are acceptable.
No obvious issues with the new constants.

code/perception/src/global_plan_distance_publisher.py (6)

7-7: Using RoadOption for clarity is a good step.
Replacing magic numbers with enumerations improves readability.

---

62-62: Topic name change aligns with the new naming convention.
Switching to "/lane_change" is consistent with the broader rename.

---

91-98: Enumerated checks for normal driving options.
Relying on RoadOption.VOID, LEFT, RIGHT, STRAIGHT fosters explicitness.

---

103-108: Extended LaneChange message with position is logical.
Publishing the current route position can provide richer context.

---

112-115: Conditional lane change checks.
Ensuring we only set lane_change=True if we detect left/right lane changes is clearer.

---

131-135: Fallback to LANEFOLLOW for repeated lane changes.
Setting the second upcoming road option to LANEFOLLOW prevents unwanted double lane changes.

code/planning/src/behavior_agent/behaviors/lane_change.py (2)

110-111: Question the conditional usage of RoadOption.CHANGELANERIGHT.
Here, the condition if RoadOption.CHANGELANERIGHT: sets lane_pos = 1 without comparing it to self.change_option. This might always evaluate to true if RoadOption.CHANGELANERIGHT is a non-zero constant, leading to unintended logic. Consider confirming if the check should instead be:

- if RoadOption.CHANGELANERIGHT:
+ if self.change_option == RoadOption.CHANGELANERIGHT:

---

285-288: Ensure early-right lane changes are disallowed if no lane exists.
The logic at line 285 only checks lane-free conditions when changing to the left. This aligns with the comment about not changing to the right too early. However, make sure you also detect if a right lane is non-existent and handle it safely to prevent abrupt lane shifts onto walkways.

Also applies to: 295-298

Reviewing files that changed from the base of the PR and between 0513e83 and dedd7f3.

• code/planning/src/behavior_agent/behaviors/lane_change.py (5 hunks)

code/planning/src/behavior_agent/behaviors/lane_change.py (1)

283-349: Verify lane change approach for right lane
The code explicitly handles early lane changes only when self.change_direction is LaneFreeDirection.LEFT. Lane changes to the right do not undergo the same lane-free check in this approach block, which can be intentional to prevent unintended right-lane maneuvers. However, if you plan to allow early right-lane changes under certain conditions, you might need a symmetrical check.

Would you like to:

1. Keep the existing logic that prevents early right-lane changes?
2. Add a similar lane-free approach check for LaneFreeDirection.RIGHT?

Reviewing files that changed from the base of the PR and between dedd7f3 and 5c4d5ae.

• code/planning/src/behavior_agent/behavior_tree.py (1 hunks)
• code/planning/src/behavior_agent/behaviors/lane_change.py (5 hunks)

• code/planning/src/behavior_agent/behavior_tree.py

• GitHub Check: Build and push image

code/planning/src/behavior_agent/behaviors/lane_change.py (9)

116-123: Good approach to remove potential blocking stop marks.

Removing the overtake stop marks before executing a lane change is a good practice to prevent conflicts between different behaviors.

---

125-145: Clever handling of overtaking scenarios with lane changes.

This is an elegant solution to handle the case where the vehicle is already in an overtaking maneuver when a lane change to the left is requested. By adapting the overtake end position rather than executing a separate lane change, you avoid unnecessary maneuvers.

---

232-238: Good optimization to skip unnecessary states.

Skipping the approach phase when the lane change is already determined to be free is an effective optimization that streamlines the behavior flow.

---

284-284: Potential issue with left-only early lane change logic.

The condition self.change_direction is LaneFreeDirection.LEFT means early lane changes are only attempted when changing to the left lane. While this makes sense based on the PR objective comment about avoiding driving on walkways, this could limit functionality.

Consider whether this is the intended behavior and if there are scenarios where early lane changes to the right would be beneficial and safe. If you want to be more selective, consider checking for specific road conditions rather than disabling all right lane changes.

---

295-326: Counter-based reliability pattern for lane-free checks.

Using a counter to require multiple consecutive positive lane-free checks is an excellent approach to handle inconsistencies in sensor data or perception. This helps prevent premature lane changes based on false positive checks.

---

4-5: Good addition of Point for positional awareness.

Adding the Point import from geometry_msgs.msg to incorporate positional data in lane change decisions is a valuable enhancement that provides more context for decision-making.

---

157-158:

❓ Verification inconclusive

Validate coordinate transformation.

Make sure that the position values from the lane_change message are consistent with the coordinate system expected by the local_pos transformation. It would be safer to add a comment documenting the coordinate system expectations or add validation for the position values.

---

🏁 Script executed:

#!/bin/bash
# Checking for coordinate system documentation or validation

# Look for coordinate system documentation
echo "Looking for coordinate system documentation..."
rg -A 5 -B 5 "coordinate system" --glob "*.py" --glob "*.md"

# Check the LaneChange message definition to understand position field
echo "Checking LaneChange message definition..."
rg -A 10 "LaneChange.msg" --type md,txt

# Check for other transformations of position fields for comparison
echo "Looking for similar position transformations..."
rg -A 3 -B 3 "inverse\(\) \* Point2\.new\(" --glob "*.py"

Length of output: 17663

---

Action: Add inline documentation/validation for coordinate transformation consistency.

Please ensure that the position values from the lane_change message (i.e. self.change_position.x and self.change_position.y) are in the coordinate system required by the local position transformation. Consider the following:

• Add an inline comment or reference to the design documentation (e.g., see doc/research/paf24/intermediate_layer/DesignDocument_TopDownMap.md) that clearly states the expected coordinate system.
• Optionally, implement a validation or assertion to confirm that the lane_change message values are properly formatted before applying the transformation.
• Compare this transformation with similar operations (e.g., in local_planner or radar_node) to ensure consistency across the codebase.

---

540-546:

❓ Verification inconclusive

Verify vector addition safety for position calculation.

The code adds a forward vector to the transformed position, but without clear documentation of the coordinate system. Ensure that this addition is correctly applying a 5-meter offset in the direction of travel.

---

🏁 Script executed:

#!/bin/bash
# Look for similar Vector2.forward() usage

echo "Searching for Vector2.forward() usage..."
rg -A 3 -B 3 "Vector2\.forward\(\)" --glob "*.py"

echo "Checking Vector2 class definition..."
rg -A 20 "class Vector2" --glob "*.py"

Length of output: 6358

---

Clarify Coordinate System for 5-Meter Offset

The calculation in lane change (lines 540–546) applies a 5-meter offset by adding Vector2.forward() * 5.0 to the transformed position. We observed that similar patterns appear in other parts of the codebase (e.g., in the pure pursuit controller, ACC, and mapping modules), which suggests that Vector2.forward() is consistently used to generate a forward offset. However, the underlying coordinate system—specifically, whether Vector2.forward() reliably returns a unit vector in the proper travel direction—is not clearly documented here.

Please verify that:

• Vector2.forward() returns a unit vector aligned with the intended forward direction.
• The transformation applied via hero_transform.inverse() correctly positions the offset relative to the vehicle's coordinate frame.
• Any assumptions about the coordinate system are either documented or referenced elsewhere in the codebase.

---

434-439:

❓ Verification inconclusive

Inconsistent check method between Approach and Wait.

In Approach.update(), the lane free check uses check_method="fallback" (line 289) while in Wait.update(), it uses check_method="lanemarking" (line 438). This inconsistency could lead to different behavior between the two states.

If the intentional difference is to have stricter checks during waiting vs. approaching, consider adding a comment explaining this design decision.

---

🏁 Script executed:

#!/bin/bash
# Check for documentation of check_method parameter

# Look for definitions or usage of check_method parameter
echo "Looking for check_method documentation or usage..."
rg -A 5 -B 5 "check_method" --glob "*.py"

# Look for definition of is_lane_free method
echo "Looking for is_lane_free method definition..."
rg -A 10 "def is_lane_free" --glob "*.py"

Length of output: 15400

---

Clarification Needed: Document Intentional Use of Different check_method Values

The repository intentionally uses both "fallback" and "lanemarking" as valid options for the check_method parameter (see documentation in code/mapping/ext_modules/mapping_common/map.py). For example, in lane_change.py one branch uses "fallback" (when self.change_detected is true and the direction is left) while another branch uses "lanemarking". A similar pattern is observed in other behaviors (e.g., in Approach vs. Wait states).

To avoid confusion, please verify that this deliberate difference in lane free-checks is intended. If so, consider adding an inline comment explaining why one state (or branch) uses "fallback" while another uses "lanemarking", clarifying the design rationale behind these choices.

Reviewing files that changed from the base of the PR and between 7d6e938 and 5bf0a81.

• code/planning/src/behavior_agent/behaviors/lane_change.py (5 hunks)

• GitHub Check: Build and push image

code/planning/src/behavior_agent/behaviors/lane_change.py (4)

68-69: Re-initializing LANECHANGE_FREE on each Ahead initialization may cause logical confusion.
Every time the Ahead behavior starts, LANECHANGE_FREE is set to False. If other behaviors rely on this global flag’s prior state, the reset here could lead to unexpected transitions. Verify whether this repeated re-initialization accurately reflects the intended design.

---

128-140: Confirm overtake end logic consistency.
When an overtake is already in progress and a left-lane change is requested, the code adapts the overtake end position rather than performing a separate lane change. Double-check that the newly computed end_transition_length and end_pos properly facilitate a safe, completed maneuver in all edge cases (e.g., slow-moving traffic).

---

157-177: Validate stop mark usage during lane change.
The code creates a 20m-long stop mark slightly offset from the hero vehicle’s position. While this helps block the lane for oncoming or conflicting traffic, ensure that this offset correctly accounts for different road widths and does not inadvertently place the stop mark where it can cause collisions with adjacent lanes or sidewalks.

---

557-568: Returning Status.FAILURE upon successful lane change is intentional.
This return value can appear counterintuitive; however, based on prior conversations (), you are using FAILURE to terminate the lane change subtree. As long as the parent behavior is designed to interpret this as a completed lane change, no further changes are required.

Reviewing files that changed from the base of the PR and between 5bf0a81 and 2a44169.

• code/planning/src/behavior_agent/behaviors/lane_change.py (5 hunks)

• GitHub Check: Build and push image

code/planning/src/behavior_agent/behaviors/lane_change.py (7)

110-111: LGTM! Issue fixed.

The comparison logic now correctly checks if the lane change option equals RoadOption.CHANGELANERIGHT.

---

127-147: Well-handled special case for lane changes during overtaking.

This intelligent handling of lane changes to the left when already overtaking is a good solution. It avoids redundant maneuvers by adapting the existing overtake parameters rather than executing a separate lane change.

---

562-563: LGTM! Intentional FAILURE return for behavior tree control flow.

The Status.FAILURE return when the lane change is finished is intentional to signal termination of the subtree and exit the lane change behavior sequence, as confirmed in the learned feedback.

---

535-541:

❓ Verification inconclusive

Verify trajectory calculation logic during lane change.

The calculation to determine if the lane change is complete involves getting a point 5 meters behind the global change point. Ensure this logic works correctly for various lane geometries and vehicle approaches.

---

🏁 Script executed:

#!/bin/bash
# Check for any existing tests or simulation scenarios involving lane changes

# Look for test files related to lane changes
fd "test.*lane.*change" --type f

# Look for simulation scenarios that might test lane changes
fd "lane.*change.*scenario" --type f
fd "scenario.*lane.*change" --type f

Length of output: 112

---

Action Required: Manually Verify Lane Change Trajectory Calculation
Our search for automated tests related to lane change scenarios returned no output. This suggests that the trajectory calculation logic hasn't been validated via tests yet. Please ensure that the transformation applied using _get_global_hero_transform() combined with the addition of Vector2.forward() * 5.0 truly yields the intended 5-meter shift in various lane geometries and vehicle approach scenarios.

• Confirm that _get_global_hero_transform() provides correct global coordinates.
• Verify that the transformation inversion and addition of the forward vector correctly computes the new local position.
• Consider adding or updating simulation tests to cover diverse lane change geometries.

---

93-94:

❓ Verification inconclusive

Validate the usage of lane_change.position.

This code now extracts the position field from the lane_change message, which was newly added to the LaneChange message type. Ensure that all publishers of this message include valid position information.

---

🏁 Script executed:

#!/bin/bash
# Find all locations that publish to lane_change topics and check if they populate the position field

# Search for lane_change publishers in the codebase
echo "Looking for lane_change publishers..."
rg -A 5 -B 5 "publish.*lane_change" --type py

Length of output: 132

---

ACTION REQUIRED: Verify that all lane_change publishers are setting the new position field properly.

The current change extracts lane_change.position from the message, but our automated search did not locate any code publishing to the lane_change topic that explicitly sets the position field. Please perform a manual review of the publisher implementations for the LaneChange message to confirm that they correctly populate this field.

---

282-326:

❓ Verification inconclusive

Consider a different approach for right-lane change safety.

The current implementation intentionally skips lane-free checks for right-lane changes to avoid premature lane changes that could lead to driving on walkways. While this addresses the immediate concern, it might not detect obstacles on the target lane early enough.

Consider implementing a progressive checking approach for right-lane changes that still performs the lane-free check but at a progressively decreasing distance as the vehicle approaches the lane change point. This would allow early detection of obstacles while avoiding premature lane changes.

---

🏁 Script executed:

#!/bin/bash
# Checking if lane-free check is implemented for other methods that could be adapted

# Check if there are adaptive or progressive checking methods in the mapping code
rg -A 5 "is_lane_free" --type py

Length of output: 6612

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Action Required: Enhance Right-Lane Change Safety Checks via a Progressive Approach

The current implementation deliberately omits early lane-free checks for right-lane changes to prevent initiating premature maneuvers (and potential incursions onto walkways). While this prevents some risks, it also delays obstacle detection on the target lane when approaching the change point. In contrast, similar functions (as seen in the mapping module and overtaking behavior) use checks with various methods (like "fallback" and "lanemarking") but do not yet incorporate a dynamic, progressive distance approach.

Suggestions:

• Evaluate updating the right-lane change logic (in code/planning/src/behavior_agent/behaviors/lane_change.py, lines 282–326) to include a progressive lane-free check. This could involve starting the check at a longer distance and then tightening the parameters (e.g., adjusting lane_length or lane_transform) as the vehicle nears the lane change point.
• Review and consider adapting techniques similar to those in code/mapping/ext_modules/mapping_common/map.py where parameters like reduce_lane are leveraged to dynamically adjust the lane-free evaluation.

Please verify that this change will not introduce premature lane changes in other scenarios while still ensuring obstacles are detected early enough.

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434-439:

❓ Verification inconclusive

Inconsistent lane-free check methods between Approach and Wait.

The Approach class uses "fallback" method while the Wait class uses "lanemarking" method for the lane-free check. These inconsistencies could lead to different behaviors in different phases.

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🏁 Script executed:

#!/bin/bash
# Check the implementation differences between lane-free check methods

# Find the implementation of is_lane_free
rg -A 20 "def is_lane_free" --type py

# Look for documentation on the different check methods
rg "check_method" --type py

# Find usage patterns of the different methods
rg "check_method=\"fallback\"" --type py
rg "check_method=\"lanemarking\"" --type py

Length of output: 7730

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Review Note: Verify Consistency of Lane-Free Check Methods

The usage of the is_lane_free method appears to vary across behavior modules. For example, in some parts of the code (including within lane_change.py and overtake.py), the "fallback" method is used, while in other parts (such as the snippet shown in lane_change.py and in leave_parking_space.py), the "lanemarking" method is applied. The original comment mentioned that the Approach behavior uses "fallback" whereas the Wait behavior relies on "lanemarking." Given that the underlying function supports several check methods ("rectangle", "lanemarking", and "fallback"), please verify that these differences reflect an intentional design choice rather than an oversight.

Action Items:

• Confirm whether the distinct methods (“fallback” vs. “lanemarking”) are deliberately chosen for different phases (e.g., Approach vs. Wait) or if they should be unified.
• Review the configuration across the relevant behavior classes (including Approach, Wait, lane change, and overtake) to ensure consistent lane-checking criteria and predictable behavior.
• If the divergence is unintended, refactor the code to use a consistent check method or clearly document the rationale for the differences.