dairejpwalsh / helios

HELIOS - the Heidelberg LiDAR Operations Simulator - is a software package for interactive real-time simulation and visualisation of terrestrial, mobile and airborne laser scan surveys written in Java.

helios

Heidelberg LiDAR Operations Simulator (HELIOS)

HELIOS is a software package for interactive real-time simulation and visualization of terrestrial, mobile and airborne laser scanning surveys written in Java. Official website: https://www.uni-heidelberg.de/helios

Table of Contents

• Install
• Usage
• Documentation
• Authorship
• License

Install

The pre-built project is available here with a test scene and survey. Note that for faster simulations building the project is recommended.

To build the project, first install the dependencies, then compile the source code, and finally execute it.

Requisites

• Oracle Java 1.8
• Maven 3

You can use java -version and mvn -v to check if you already have installed those on your computer.

Linux/Ubuntu:

They can be installed by:

sudo apt-get install oracle-java8-installer maven

Windows:

In Windows installation is less straightforward:

• Java JDK
  1. Download the Java JDK 8 and install it
  2. Create the environment variable JAVA_HOME to point to the JDK folder
     (e .g: JAVA_HOME=C:\Program Files\Java\jdk1.8.0_151)
  3. Add to the PATH the value %JAVA_HOME%\bin
• Maven
  1. Download the Maven binary zip
  2. Unzip it and move it to the desired folder (e. g. C:\apache-maven-3.5.2)
  3. Add to the PATH the bin folder inside (e. g. C:\apache-maven-3.5.2\bin)

Compilation

Download the source code from this web site or from git:

git clone https://github.com/GIScience/helios.git

Then inside the root folder simply execute:

mvn package

Eclipse IDE

To add this project to Eclipse go to File > Import > Existing Maven Projects and select helios folder.
You may also want to disable the spell checker: right click in the project > Checkstyle > Deactivate Checkstyle

Usage

HELIOS supports both single-ray and full-waveform simulations. Currently the default mode is the full-waveform. The selection between this two methods is done in the source code when creating the detector object in XmlAssetsLoader.java.

Input

The argument of the program is the survey XML file, also the 3D models of the scene pointed in the survey are needed. See Wiki: Basic input data for further details.

Execution

From the root folder run:

java -jar target/helios.jar <survey-file>

To run the example survey:

java -jar target/helios.jar data/surveys/demo/tls_arbaro_demo.xml 

To use the batch mode (no visualization):

java -jar target/helios.jar <survey-file> headless

Output

Output files are generated inside output/Survey Playback folder.

• Point cloud: File named legxxx_points.xyz separated by spaces where xxx is the leg number.
  Fields:
  X Y Z I ECHO_WIDTH RN NOR FWF_ID OBJ_ID
  Example:
  -4.615 15.979 2.179 4.0393 1.4317 1 1 214275 1
• Waveform: File named legxxx_points.xyzfullwave.txt separated by spaces where xxx is the leg number.
  See FWF.md for further details.

Documentation

See Wiki.

Authorship

GIScience Research Group
Institute of Geography
University of Heidelberg

Citation

Bechtold, S. & Höfle, B. (2016): HELIOS: A Multi-Purpose LiDAR Simulation Framework for Research, Planning and Training of Laser Scanning Operations with Airborne, Ground-Based Mobile and Stationary Platforms. ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. III-3, pp. 161-168. http://dx.doi.org/10.5194/isprs-annals-III-3-161-2016

Maintainers

@sebastian-bechtold @nlukac @kathapand @deuxbot

The first HELIOS version with full-waveform support is available in this repository maintained by @nlukac.

License

See LICENSE.md.