Official Groundhog Day Timetables

Introduction

When SimSig release a simulation, typically a number of "groundhog" day timetables (GHDTTs) will be provided with the simulation, depending on the time periods that the simulation covers. These are currently 2009-10-15, 2015-04-08, and 2019-01-09. This page describes the standardisation required to ensure sims chain correctly with train types etc matching between adjacent simulations.

Master Data Set

All GHDTTs must be maintained within the online tool (not available to the public). This can export virtually all the details required for each schedule, such as train types, decisions, stock typing, etc, with the exception of seeding which must be done by hand in the SimSig Loader. Because of this, the timetable should be tested from midnight to 27:00 or thereabouts, and any issues fixed in the online tool, before adding any seeding.

Decisions & Choices

Work has already been done to check no alternate choice trains (typically Q/Y paths) run at the same time, usually in Decisions. If you find a set of trains without decisions that look like they should never run together, a decision should be added to those schedules. However, if the train(s) pass through various sims, it would be wise to consult with others as they may have opinions or knowledge on appropriate weighting.

Stock Choices

Where possible, trains should be assigned stock types that actually ran on the day, not their planned stock line per CWN / stock books. We have a number of resources and spreadsheets that cover these three periods.

Timing Alterations

Some schedules have additional padding for scheduled engineering work. The work itself may or may not have taken place, and the train(s) in reality may have arrived at their next timing point significantly early. Schedules must not be altered in such situations as real life signallers have to deal with this as well.

The railhead treatment trains, on the other hand, may need splitting when they exit and re-enter a simulation multiple times. There is an option to split a schedule in the online, but it is irreversible once confirmed. Therefore, the original schedule should be duplicated and made to never run (remove all days of week). The duplicate can then be split as required.

Seeding

The 2009 timetables should have midnight and 04:45 seed start times. The 2015 and 2019 timetables should have these plus an additional 14:00 seed start. The lack of 14:00 for 2009 is to ensure consistency across the SimSig simulation range.

While seeding gaps could be used to reduce the number of "stopped at red signal" messages, this is not preferred as it creates more work for very little benefit.

Over Midnight Issues

The online tool exports schedules for a specific single date. This means there might be trains that terminate just after midnight and don't get imported; and trains that start at 24:01 or later and similarly don't get imported as they don't run on the selected date. Therefore a check of the prior and next day timetables should be made to ensure nothing gets left out. This includes for seeding.

Testing

Testing should be undertaken by testers other than the timetable author. The author may assist with adjacent sims if necessary, and if the author did not write the adjacent timetable being tested.

Logging

All issues should be logged to Mantis.

User Submitted Timetables

User submissions that purport to be GHDTTs, whether specifically or implicitly, will not be accepted for upload. This is to avoid confusion and complaints over incompatibility.

Last edited by GeoffM on 27/06/2023 at 20:50