Open Rails Test Environment And Physics Description
10 January 2017 - Route Design page added, which has information on how to implement some of the new OR features.
07 January 2017 - Test Route updated.
21 June 2016 - Test model added - Aux Water Tender
Open Rails is an open source train simulator that is currently being developed, and new features are continually being added to it. Open Rails have set as one of its aims that train performance should mirror real life operation as closely as possible. Thus a way of comparing the train's performance in the simulator, and in real life is critical to achieve this outcome. In addition, when a problem is identified, it is important to be able identify the problem, or if necessary communicate it in a way that makes it easy for different people to compare outcomes and provide suggested remedies.
The guidelines and methodology in the following pages describe a common and consistent test environment that allows all users to test locomotives and rolling stock against real life scenarios. They allow the testing of the locomotive, under 'controlled' conditions, which eliminates as many unknowns as possible.
All rolling stock has been configured with what is believed to be the optimal settings to achieve the most realistic performance in Open Rails for NSWGR rolling stock. The settings are based upon NSWGR practice in the early 1960s, so if setting up stock from other systems some variations may need to be considered.
This guide covers the following aspects to be considered by the tester, as they will combine together to give the optimal performance for steam locomotives:
- ENG and WAG files - Importance of correctly setting, and researching prototypical information about your rolling stock.
- File Structures and Layout - Describes the structure and layout of ENG and WAG files for Open Rails, and provides some example templates.
- Couplers - Description of settings used.
- Brakes - Description of common brake configurations and settings used.
- Brake Parameters - OR Parameters used to define brake settings.
- Brake Controllers - BrakeController tokens used in OR to define brake settings.
- Locomotive Adhesion - Description of the physics impacting a locomotives adhesion, and slip properties.
- Train Resistance - Description of diferent types of resistance impacting a train's operation, and the principal track geometry parameters.
- Resistance Setting - Description of how to set resistance parameters.
- FCalc - How to use FCalc2.
- Resistance Parameters - OR Parameters used to define resistance settings.
- Lights - Description of settings used for lights.
- Light Parameters - OR Parameters used to define light settings.
- General description of steam locomotives principles of operation
- General description of driving steam locomotives
- Steam Effects - Description of settings used for locomotive steam effects
- Steam Parameters - Description of settings used
- Steam Parameters - OR Parameters used to define steam settings
- Advanced Steam Parameters - Description of settings that can be used by advanced content modellers
- Describes the values in the extended Steam HUD
- Understanding the test route, and some of the testing scenarios that can be run on it
- Test Stock - Locomotives and wagons.
- Typical Tests and outcomes
- Steam Train Load Estimator
- Diesel Parameters - OR Parameters used to define diesel settings.
Some simple converters are located on this page to assist in moving between imperial and metric units of measure.
Note: Information currently provided is, to the best of my knowledge correct at the time of writing. Full responsibility is on the user for any problems created by using this information.
Physics Setting Philosophy - only key configuration parameters will be changed between individual units, this may not achieve a true realistic response, but will allow comparitive response between different units.
Online Tools and Calculators
Some simple online tools and converters are provided to support the developement of physics for steam locomotives and trains:
- Units of Measure - converts between imperial and metric units of measure, such as length, distance, volume, speed, force, gradients.
- Force - converts imperial force to metric units of measure (Newtons).
- Brake Force - calculates braking forces and associated parameters.
- Wagon Brake and Handbrake Force - calculates brake forces for locomotives and wagons.
- Brake Cylinder Size - calculates size of brake cylinder required.
- Brake Pipe Volume - calculates the volume of the train brake pipe on a wagon.
- Reservoir Charging Rate - calculates the charging rate of the main air compressor.
- Boiler Parameter - Saturated - calculates tractive effort, steam generation, coals usage, grate area, evaporation area, and boiler volume.
- Boiler Parameter - Superheated - calculates tractive effort, steam generation, coals usage, grate area, evaporation area, and boiler volume.
- Steam and Water Usage - Imperial - calculates steam and water usage based upon the design sizes of the steam cylinder, and throttle settings.
- Steam and Water Usage - Metric - calculates steam and water usage based upon the design sizes of the steam cylinder, and throttle settings.
- Curve Speed - converts curve radius from degrees to other units (such as metres, etc), calculates various speed limits around curves.
- Critical Speed - calculates critical speed of the locomotive, ie speed at which maximum power is developed.
- Train Load Estimator - estimates the maximum load hauling capacity of a steam locomotive.
Open Rails Physics Parameters
Some of the key parameters used by Open Rails to define the physics and operation of railway locomotive, wagons and cars can be found on the following pages:
- Brakes - describes the parameters used to define brake operation.
- Lights - describes the parameters used to define the operation of lights.
- Resistance - describes the parameters used to define adhesion.
- Steam (standard) - describes the parameters used to define a standard steam locomotive.
- Steam (advanced) - describes the parameters used to define an advanced steam locomotive setup.
- Diesel (standard) - describes the parameters used to define a standard diesel locomotive.
- Diesel (advanced) - describes the parameters used to define an advanced diesel locomotive setup.
Expressions of Interest
I am seeking people who are interested in supporting of the development of this standard (appraoch) to work with me.
The types of tasks that would be needed to advance the development:
- Researching for most "optimal" configuration parameters.
- Documenting findings.
- Converting wag and eng files.
If you are interested, please contact me through the Contact page.
Text used in wag and eng files will be colour coded as below:
Green - text that stays the same and does not need to be altered.
Red - text that needs to be altered to suit stock unit.
Blue - text that provides explanations about code.