What problem does it solve? Fusing multiple robot sensors (wheel odometry, IMU, GPS, visual odometry) into one consistent state estimate is error-prone: misconfigured boolean vectors cause oscillation, drift, or double-fused dimensions. This Skill provides correct, explained configuration patterns for the ROS robot_localization ekf_filter_node. ## Core Features & Use Cases - 15-Dimension State Configuration: Explains the EKF state vector and how to write per-source 15-element boolean config vectors for odom, imu, pose, and twist inputs. - Differential Drive + IMU Pattern: Provides a validated configuration where wheel odometry fuses velocities only and the IMU fuses absolute yaw, yaw rate, and forward acceleration, avoiding double-fusing. - Complete YAML Template: Ships a full ekf_filter_node parameter file including frame setup, two_d_mode, process noise covariance, and initial estimate covariance. - Use Case: A robotics engineer setting up localization on a differential-drive ground robot can copy the YAML, adjust topic names, and get a stable fused /odometry/filtered output without fighting TF extrapolation or drift issues. ## Quick Start Ask the AI to generate a robot_localization EKF configuration for a differential-drive robot with wheel odometry on odom/unfiltered and an IMU on imu/data.