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How to Run PAIRSIM in Headless Mode (Batch Mode)

Headless mode is useful for when the application needs to run without a GUI.

Downloading Headless Simulator

There are two options to run a headless simulation:

Info

  • In your working terminal make sure you DO NOT source ros2, or the ros2-for-unity plugin will not work

  1. Download binary (only compatible with Linux) (recommended)

    a. Download the latest PAIRSIM headless build here

    b. Navigate to the directory containing the .x86_64 executable file

    c. The first time you may need to set the executable permissions with chmod +x PAIRSIM_batch.x86_64

    d. Configure your desired parameters in the configuration files ~PAIRSIM_config/, as discussed below

    e. Run ./PAIRSIM_batch.x86_64 -batchmode -nographics

  2. Build and Run From the Unity Project

    a. Finish setting up the project as detailed in Step 2

    b. Close out of Unity Editor

    c. Navigate to the project's root directory, run the convenience script headless_build.sh.

    d. Configure your desired parameters in the configuration files ~PAIRSIM_config/, as discussed below

    e. The build is now located in the ./Build/Linux directory. Run it with ./Build/Linux/PAIRSIM_batch.x86_64 -batchmode -nographics

Important Configuration Parameters

For an overview on how PAIRSIM configuration files work, see here.

Create a new configuration file (any name) for the headless simulation to work properly:

~/PAIRSIM_config
└── Scenarios
    ├── Default.dat
    └── Headless_default.dat

In the Scenarios configuration file ensure that the following value is set:

"ModeSwitchState": true,

This ensures that PAIRSIM uses an external race control source, as described here

Map List

To select your racetrack, ensure that the following value is set to your desird track:

"SelectedTrack": 0,

The following is the list of racetrack enumerations:

value racetrack
0 Autodromo Nazionale Monza
1 Giant Skidpad
2 Las Vegas Motor Speedway
3 Autodromo Nazionale Monza (Low-Poly)
4 Kentucky Speedway
5 Indianapolis Motor Speedway (No Banking)
6 Indianapolis Motor Speedway

If using Giant Skidpad, ensure that the LAT/LON/HEIGHT/YAW origin values are set in the configuration file 

  "lat_input": 0.0,
  "lon_input": 0.0,
  "height_input": 0.0,
  "yaw_input": 0.0,

Headless Race Control

When running headless, the PAIRSIM GUI can no longer be used to issue race control flags, and instead needs to take race control commands from an external flag spoofer via the following ROS2 topics: /flag_spoofer/vehicle_flag and /flag_spoofer/track_flag. Both of these topics are std_msgs/UInt8.msg. To enumerate flags, PAIRSIM uses Marelli race control by default.

Track Flag List

The following are the track flag enumerations:

value track flag
3 Red
9 Full-Course Yellow
1 Green
37 Waving Green
40 G40
60 G60
80 G80
100 G100
120 G120
130 G130
140 G140
145 G145
150 G150
155 G155
160 G160
165 G165
170 G170
175 G175
180 G180
185 G185
190 G190

Vehicle Flag List

The following are the vehicle flag enumerations:

value vehicle flag
0 None
25 Orange
7 Yellow
34 Stop
4 Black
33 Engine Kill
36 Attacker
35 Defender

Copyright 2024 Purdue AI Racing

All code is licensed under the Apache 2.0 License. All assets are distributed under the CC BY-NC License.