Tinker Niche

  Running GUI on sample hardware Sample GUI showing DDU interface for WAP Series Locomotive Driver Display Units are used in Locomotives to provide HMI for operating the locomotives. Various realtime sensor information of the locomotive/train are presented in user friendly interface on an LCD screen on an SBC.  The WAP Series locomotives use a variant of the MultiFunction Vehicular Bus (MVB) called MICAS. It is a master/slave realtime bus operating in the locomotive and beyond and can work over long distances (~4kms). Information is exchanged over the bus in the form of process data and messages. It supports connection via wire or fiber. There was a need to implement a Driver Interface while being interfaced to the MVB/MICAS. The design also had to be kept similar to existing products so as to retain locopilot familiarity and also provide similar features. Just as a fun exercise, an oscilloscope was used to dump traffic on the MVB from an available setup and manually validated...

The WDP4/WDG4 locomotive is a diesel locomotive used actively by the Indian Railways. It is a locally built General Motors Electro-Motive Division's GT46MAC (freight) and GT46PAC (passanger) variant. More details can be found here  WDP4/WDG4 info on Wikipedia The various gauges on this locomotive are Analog and there was a need to digitize them and provide a single console like is common on many locomotive Driver Display Units.  A commonly available industrial x86 SBC which could run Linux and a GUI was chosen. It was interfaced at a location on the loco rack where digital signals were available. It could show a locopilot various readings on the console: Speed, Brake Pipe/Cylinder pressure, BE/TE, Notch position and also various fault conditions. This DDU was used in a few locos and has worked reliably. Below is a picture of a physical meter and how it looks on the implemented DDU. WDP4 Locomotive Original Wikimedia image here