Mazda Cab Signals are the PTC Solution We Needed

While driving in a brand new rental Mazda sport wagon in Colorado I noticed something interesting on the instrument cluster.

There was a dynamic speed limit indication accompanied by a red tick on the speedometer indicating the currently detected speed limit. Now this sort of information has been available in Waze for some time, accurately using smart phone grade GPS to pull a road segments speed limit from a crowd sourced database and displaying it on the interface. Using something like Android Auto this could be displayed to he driver in any number of ways.

The cybersecurity implications of this aside, I noticed an interesting Mazda party trick that Waze could not perform and that was the seeming ability to detect temporary speed restrictions, aka work zone speed limits. Waze explicitly rejects trying to track TSR's, even for long term work zones. Although achievable through traditional data collection methods, I was aware that the vehicle was equipped with forward facing cameras for its lane-assist feature (or MCAS) and if on-board systems could keep track of lanes, they could also recognize wayside speed limit signs and display them on cab signal, possibly augmented by a Waze style database.

The current national Class 1 PTC standard, ETMS, relies on wireless data and GPS to track a trains position and compare is, Waze style, to a database of authorized speed limits. The problem this creates are clunky data networks that result in slow setup time and en-route loss of connectivity as well as occasional mass outages that can halt traffic across a railroad's entire network. The preferable solution has been evident in the field of vehicle automation for over a decade now. Computer vision systems just look at wayside signs (and/or signals) the same way the human engineer does. To the extent that wayside signs are vulnerable to impairment computer vision doesn't have to replace the current "Waze" type system, but in case ETMS suffers a failure, the backup solution isn't halt all traffic (or god forbid just let the crews do their job), but fall back to wayside sinage detected by computer vision and enforced by the on board apparatus