/oscillator

First part of the fourth System Simulations project: A damped harmonic oscillator

Primary LanguageJava

Oscillator Build Status

First part of the fourth System Simulations project: A damped harmonic oscillator

Getting started

These instructions will install the system in your local machine.

Prerequisites

  1. Clone the repository, or download source code

    $ git clone https://github.com/juanmbellini/oscillator

    or

    $ wget https://github.com/juanmbellini/oscillator/archive/master.zip

  2. Install Maven, if you haven't yet

    Mac OS X

    $ brew install maven

    Ubuntu

    $ sudo apt-get install maven

    Other OSes

    Check Maven website.

Installing

  1. Change working directory to project root (i.e where pom.xml is located):

    $ cd <project-root>

  2. Let maven resolve dependencies:

    $ mvn dependency:resolve -U

  3. Create jar file

    $ mvn clean package

    Note: The jar file will be under <project-root>/target

Usage

You can run the simulation with the following command:

$ java -jar <path-to-jar> [arguments]

In order to customize the simulation, you can specify different types of parameters.

Oscillating particle mass

You can specify the particle's mass with the --custom.system.particle-mass argument.

For example, if you want a mass of 150.0, you would execute:

$ java -jar <path-to-jar> --custom.system.particle-mass=150.0

This argument has kilgrams [kg] as unit.

The default value is 70.0.

Starting position

You can specify the particle's starting position (in the 'x' axis) with the --custom.system.initial-x argument. For example, if you want to start at 0.80, you would execute:

$ java -jar <path-to-jar> --custom.system.initial-x=0.8

This argument has meters [m] as unit.

The default value is 70.0.

Spring constant

You can specify the spring's constant with the --custom.system.spring-constant argument. For example, if you want a spring constant of 2000, you would execute:

$ java -jar <path-to-jar> --custom.system.spring-constant=2000

This argument has kilgroms over square seconds [kg/s^2] as unit.

The default value is 10000.0.

Viscous Damping Coefficient

You can specify the viscous damping coefficient with the --custom.system.viscous-damping-coefficient argument. For example, if you want a coefficient of 50, you would execute:

$ java -jar <path-to-jar> --custom.system.viscous-damping-coefficient=50

This argument has kilgroms over seconds [kg/s] as unit.

The default value is 100.0.

Integration strategy

You can specify the integration strategy (i.e Verlet-Original, Verlet-Trick, Beeman or 5th order Gear) with the --custom.simulation.strategy argument. For example, if you want to use Verlet-Original, you would execute:

$ java -jar <path-to-jar> --custom.simulation.time-step=VERLET

There is no default value.

Note: Possible values are: VERLET, VERLET_TRICK, BEEMAN or GEAR.

Time step

You can specify the simulation time step with the --custom.simulation.time-step argument. For example, if you want a time step of 0.01, you would execute:

$ java -jar <path-to-jar> --custom.simulation.time-step=0.01

This argument has seconds [s] as unit.

The default value is 0.001 (1 ms).

Total time

You can specify the total simulation time with the --custom.simulation.duration argument. For example, if you want a duration of 10, you would execute:

$ java -jar <path-to-jar> --custom.simulation.duration=10

This argument has seconds [s] as unit.

The default value is 5.0�.

Ovito file path

You can specify the path where the Ovito file will be saved with the --output.ovito argument. For example, if you want to save the file in the /tmp directory, you would execute:

$ java -jar <path-to-jar> --custom.output.ovito=/tmp/ovito.xtz

There is no default value.

Positions file path

You can specify the path where the positions file will be saved with the --output.movement argument. For example, if you want to save the file in the /tmp directory, you would execute:

$ java -jar <path-to-jar> --custom.output.movement=/tmp/positions.m

There is no default value.

Note: The positions file is just a MatLab/Octave script that has two intialized array variables: x and y, both with the same amount of elements (i.e the 'x' and 'y' values for each step of the simulation).

Authors