Controller Package

Pure pursuit controller for F1TENTH autonomous racing with velocity control and safety monitoring.

Quick Start

# Build
colcon build --packages-select controller_pkg
source install/setup.bash

# Real car
ros2 launch controller_pkg controller.launch.py

# Simulation
ros2 launch controller_pkg controller.launch.py sim_mode:=true

Launch Parameters

Parameter	Default	Description
sim_mode	false	Use simulation topics if true

Topics

Input

• /planned_waypoints - Path from lattice planner (ae_hyu_msgs/WpntArray)
• /pf/pose/odom (real) / /ego_racecar/odom (sim) - Vehicle pose

Output

• /drive - Ackermann drive commands (ackermann_msgs/AckermannDriveStamped)

Key Configuration

Edit config/controller_config.yaml:

# Pure Pursuit
lookahead_distance: 2.5       # Target point distance (m)
lookahead_ratio: 0.4          # Speed-dependent lookahead
min_lookahead: 0.5            # Minimum lookahead (m)
max_lookahead: 3.0            # Maximum lookahead (m)

# Vehicle
wheelbase: 0.35               # Vehicle wheelbase (m)
max_steering_angle: 0.4       # Max steering (rad)
max_steering_rate: 2.0        # Max steering rate (rad/s)

# Speed Control
target_speed: 5.0             # Default speed (m/s)
max_speed: 8.0                # Speed limit (m/s)
use_planner_velocity: true    # Use waypoint speeds
velocity_scale_factor: 1.0    # Speed scaling factor

Control Algorithm

1. Waypoint Selection: Find target point based on lookahead distance
2. Pure Pursuit: Calculate steering angle to target point
3. Speed Control: Use waypoint velocities or constant speed
4. Safety Limits: Apply steering and speed constraints
5. Command Output: Publish Ackermann drive messages

Prerequisites

• Lattice planner running (/planned_waypoints topic)
• Localization running (odometry)
• Vehicle hardware or simulation ready