Skip to content

README.md

Latest commit

 

History

History
117 lines (95 loc) · 4.45 KB

README.md

File metadata and controls

117 lines (95 loc) · 4.45 KB

Example Usage Guide

This document explains how to configure and use IGHAStar for different planning scenarios.

Configuration Files

Configuration files are located in examples/standalone/Configs/ and include:

  • Vehicle Parameters: Length, width, maximum velocity, steering limits
  • Planning Parameters: Resolution, tolerance, epsilon values
  • Environment Settings: Map resolution, timesteps, control discretization

Available Configuration Files

  • kinematic_example.yml - Kinematic planning configuration
  • kinodynamic_example.yml - Kinodynamic planning configuration
  • simple_example.yml - Simple planning configuration
  • ros_kinodynamic_example.yml - ROS integration configuration

Modifying Start and Goal Points

To change the start and goal positions for path planning, you can either:

  1. Edit the configuration file to modify the default start/goal or add test cases
  2. Use the --test-case argument to select from predefined test cases

Configuration File Structure

For Kinematic Planning:

map:
  name: "Berlin_0_1024.png"
  dir: "Maps/street-png"
  start: [94.5, 19.5, 2.8284062641509644]  # [x, y, heading]
  goal: [38.7, 81.6, 0.6324707282184407]   # [x, y, heading]
  size: [1024, 1024]
  res: 0.1
  test_cases:
    case1:
      start: [94.5, 19.5, 2.8284062641509644]
      goal: [38.7, 81.6, 0.6324707282184407]
    case2:
      start: [17.6, 72.0, 0.9402905929256757]
      goal: [40.3, 16.9, 1.0911003058968491]

For Kinodynamic Planning:

map:
  name: "race-2"
  dir: "Maps/Offroad"
  start: [5.6, 8.9, 1.5844149127199794, 4.935323678240241, 0]  # [x, y, heading, velocity, unused]
  goal: [21.1, 46.1, 0.608009209539623, 4.516091247319389, 0] # [x, y, heading, velocity, unused]
  size: [512, 512]
  res: 0.1
  test_cases:
    case1:
      start: [5.6, 8.9, 1.5844149127199794, 4.935323678240241, 0]
      goal: [21.1, 46.1, 0.608009209539623, 4.516091247319389, 0]
    case2:
      start: [11.9, 16.8, 1.3574384016819936, 3.317266656251059, 0]
      goal: [46.6, 25.0, 0.19076360687480998, 3.2507584385704855, 0]

Coordinate System

  • x, y: Position coordinates in meters
  • heading: Orientation in radians (0 = east, π/2 = north, π = west, -π/2 = south)
  • velocity: Speed in m/s (kinodynamic only)

Map Files

Map files are stored in examples/standalone/Maps/ with the following structure:

  • generated_maps/ - Procedurally generated test maps
  • street-png/ - Street network maps
  • Offroad/ - Off-road terrain maps

Test Cases

Each configuration file can include multiple test cases with different start/goal positions. To use a specific test case:

python examples/standalone/example.py --config examples/standalone/Configs/kinematic_example.yml --test-case case2

If no test case is specified, the default start/goal from the configuration file will be used.

Parameter Descriptions

Map Parameters

  • name: Name of the map file
  • dir: Directory containing the map file (relative to examples/)
  • start: Starting position [x, y, heading] or [x, y, heading, velocity, unused]
  • goal: Goal position [x, y, heading] or [x, y, heading, velocity, unused]
  • size: Map dimensions [width, height] in pixels
  • res: Map resolution in meters per pixel

Planning Parameters

  • resolution: Starting resolution used for discretization
  • epsilon: Goal region tolerance [ate, cte, heading, vel] - along-track error, cross-track error, heading tolerance, velocity tolerance
  • tolerance: Minimum separation between vertices (your perception/map resolution should be at least this)
  • max_level: Maximum level to which the system can go (used to cache hash values)
  • division_factor: Factor by which the resolution increases every level
  • max_expansions: Maximum number of node expansions allowed
  • hysteresis: Hysteresis threshold for IGHA*-H algorithm

Vehicle Parameters

  • length: Vehicle length in meters
  • width: Vehicle width in meters
  • steering_list: Available steering angles in degrees
  • throttle_list: Available throttle values (negative = reverse, positive = forward)
  • max_vel: Maximum velocity in m/s
  • min_vel: Minimum velocity in m/s
  • del_theta: Maximum steering angle change in degrees
  • max_theta: Maximum steering angle in degrees
  • del_vel: Maximum velocity change in m/s
  • max_vert_acc: Maximum vertical acceleration in m/s²
  • RI: Rolling resistance coefficient
  • gear_switch_time: Time penalty for gear switching (multiplies reverse distance)