Driver Display Unit (DDU) using Railware/Scheron/HasslerRail Rico004 MVB/MICAS interface for WAP Series Electric Locomotive: A Prototype

 

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 with the IEC 61375, the TCN standard. It was a tedious exercise indeed.
• Later a Zeroplus MVB analyser was procured and interfaced to the same setup and it was proven that the test setup with indeed working well. The Zeroplus is limited in the number of packets it can capture, etc.
• So a feature rich MVB traffic analyser would be desirable and writing one locally was dropped as it is a time consuming process.
• Luckily Railware, an Italian manufacturer (which subsequently got acquired by Scheron and then by HasslerRail) had an MVB compatible card along with a MVB protocol dumping and analysis capability. This is called the  Rico004 by Railware and there are tools written on Windows/Linux to configure it for various modes.
•  A couple of cards were purchased and interfaced with the VCU setup and the protocol studied.
• Railware also provides MVB cards for various SBC interfaces like SPI, serial etc. A suitable card for the SBC was procured. There also was availability of libraries and APIs on Linux so that an end client could receive MVB data as a slave.
• After configuring such a setup an application to receive MVB data and present it in a real-time fashion on the SBC as DDU was implemented. 
• The above Video shows a sample UI which shows emulated data on the DDU screen. The image shows the various sensor information that would be relevant to a locopilot: including various subsystems, PIXY data, status of braking systems, meters, etc.
• This setup was working well in this test setup but due to change in project priorities never made it to actual deployment.

WAP7 Locomotive. Image from Wikimedia