gregRR - Operating Session Prep

Op Session Prep

The Operations Special Interest Group in their Compendium of Model Rail Operations recommend providing information packet to new operators to a layout. Since operation generally requires running trains between destinations on the layout, that information packet will include a description of the layout, including off layout destinations that may be represented by staging. It may also include a map showing the sub-section of a prototype railroad the layout is modeling.

While images can be scanned from hand drawings, the images shown here were created using scripts generating .svg for an information packet or layout web page. One advantage of computer generated images is that they can easily be edited, enhanced or expanded. Svg images can be embedded in a web page (i.e. .html) or translated into more common image file formats (e.g. gif, png).

The scripts mentioned below are all written in AWK, probably the original scripting language that supports user defined functions. No doubt that these scripts will be enhanced with additional features. And I believe that AWK scripts can be easily converted to other scripting languages. Of course a graphical interface would be nice, but any type of GUI requires a lot more effort. These scripts are intended to be used by modifying the text file describing the image being rendered, capturing the output and viewing or refreshing the output with a browser.

Layout Schematic

The layout schematic above is described in drgw.trk and drawn with track.k, an AWK script. A fragment of the description is shown at right. The siding command specifies the horizontal and vertical positions and length. Text specifies a position, alignment as center, left or right and the text. Spur is similar to .

Branch specifies a line at an angle to the mainline. It specifies a position to start, a length where the sign indicates to the right or left (negative) and above or below (negative) the mainline.

RevLp describe the arc completing a wye with the branch. It specifies a position from the mainline, radius that also indicates direction (negative) and above or below (negative) the mainline.

Map

The map at above illustrates the section of the Denver, Rio Grande & Western modeled by the above layout between Durango and Antonito (blue). It also shows train destinations that are modeled by staging (orange) and branch destinations modeled by hidden spurs (gray).

The map provides a context for the layout that aids in understanding the schedule that includes trains from destinations outside the layout. The map also provides a sense of distance to those destinations.

It is described in drgw.map, a fragment shown at right and drawn with latLongMap.k.

Loc provides GPS coordinate, a label and indicates text alignment if displayed. Route describes a connection. The type: route (rt), mainline (ml), branch (br) or some color indicates the color and thickness of the line connecting two locations.

Schedule

A train schedule chart, described in Frank Ellision's The Art of Model Railroading series of articles illustrates train movements across the railroad.

Of the three types of drawings, the schedule benefits the most from having a script to draw it because it evolves iteratively and will need to be redrawn often. Even after becoming mature, it is likely to be modified to add additional trains and it makes sense that there may be several schedules to choose from during an operating session

A schedule is described in 190128c.seq, a fragment shown at right and drawn with sched.k.

Mph describes the speed for all trains. Mp describes a station, its symbol, mile-post and name. Following a list of stations is a description of each train.

Each train has a name and a list of stations. Appended to the station (e.g. F,2.5) can be a departure time.

A departure time is required for the first station and may be required if there is a meet with another train most likely traveling in the opposite direction. A proper schedule should not show any trains crossing between stations. The train speed and mile-post determine the time it takes for a train to travel between stations.

The schedule shows the back tracking from Farmington because of the direction of the turnout. There are several meets. The passenger trains stop at each station and each passenger trains stop has a departure time. The Chama to Durango travels as the same time as the Alamosa to Durango time and is ahead of it on the tracks.