March 2025 monthly summary for tier4/scenario_simulator_v2: Implemented obstacle behavior debug visualization in the Motion Velocity Planner. The feature adds RViz markers for obstacle interactions (obstacle_stop, obstacle_slow_down, obstacle_cruise) and related debug markers to improve debugging visibility of planner decisions in simulation. This work enhances observability, accelerates debugging cycles, and contributes to safer obstacle handling in simulated environments. The change is anchored by commit 307f6f22766952cedf6322b02873fa91cf8be68d. No major bugs fixed this month; focus was on delivering a high-value debugging enhancement and improving developer efficiency through clearer visualization.

In November 2024, AWSIM delivered measurable improvements to vehicle dynamics realism and code quality. A first-order lag filter was implemented for float inputs and applied to steering angle and acceleration to smooth commands and reduce jitter, contributing to more realistic vehicle behavior. Code organization improvements in Vehicle.cs were completed to group time constants with their related Max inputs, improving readability and maintainability. No critical bugs were reported; the focus was on robustness and code quality enhancements that support faster iteration and tuning. These changes demonstrate strong C# development, signal-filtering techniques, and maintainable software architecture, delivering business value through more believable simulations and accelerated tuning workflows.