Davius' Fifth and notes
This is where Davius' Apprentice begins to turn freeways and motor vehicles into CAVWAYs, CAVs, and CAV Systems.
In and near urban areas currently served by automobiles with drivers, there is a need for safe, efficient, useful, secure, accessible, and sustainable mass-transit.
We need only view Davius' First Commandment to understand that our solution space must be a variable-route, variable-schedule system.
A CAV System will be comprised of Connected and Autonomous Vehicles (CAVs) and one or more CAV Highways (CAVWAYs). CAVWAY configurations, for conceptual purposes and for practical reasons, are likely to resemble those of current urban freeways. CAVWAY access will be restricted to standardized, licensed CAVs to enable safe, efficient mass transit. The existence of CAVWAYs will require cooperation between public and private sectors.
The CAV-System concept was introduced in July 2018 at the International Conference on Transportation and Development [*Reference at right] where the notion of CAV-enabled mass transit was discussed.
Separation of Requirements
On this web-site, a System-Engineering (SE) approach is taken to describe how functions performed by CAVs can be separated from those performed by the CAVWAY infrastructure, thus clarifying requirements on the former while encouraging area-specific requirements on the latter. As we shall see in good time, CAVWAYs will thus become the promised land for homeless CAVs.
State agencies** will certify CAVs with respect to standards, manage right-of-way and roadways, and define CAVWAY functions and protocols to address abnormal conditions. CAVWAY nodes will monitor traffic loads and control CAV access. A communications network (CAVNET) will connect CAVs and nodes.
Protocols rather than direct control
A CAVWAY will control CAVs indirectly, through messages, such that CAVs can coordinate safely using common protocols. Each CAVWAY will include these components: the roadway, nodes, a CAVWAY Controller (CC), a navigation system, and a communications network (CAVNET).
CAVWAYs will be controlled space, a concept inherited from controlled access, long applied to freeways. By restricting access to automobiles, motorcycles, and trucks having well-defined capabilities, freeways have been kept free of most obstacles to smooth traffic flow under normal conditions. Likewise, by restricting CAVWAY access to CAVs, CAV-System-enabled mass transit will be able to offer travelers the benefits of safety, efficiency, security, and flexible travel routes inherited from freeways.
Davius' Fifth Commandment
Give CAVWAYs and CAVs complementary responsibilities.
We take for granted that freeways, through signs, lane dividers, and barriers assist drivers to make good decisions. That CAVWAYs should do the same for CAVs is a concept handed down by "big D" (no disrespect intended) and will be a guiding principle of CAV Systems.
As we embark on this journey to The Promised Land for CAVs, we are well aware that we won't get there in one bold leap. Even as we describe our destination, we have the journey in mind.
That journey will include a relatively long phase called transition. No matter how heavenly the promised land might ultimately be, it won't matter if we cannot discover a way to reach there safely.
*Proceedings, ICTD 2018: Vineberg, M., Connected and Autonomous Vehicles and Transportation Safety, Pittsburgh PA, 15-18 July 2018, Transportation & Development Institute of ASCE, pp 56-66.
**In California, that would be the California Department of Transportation, Caltrans.
Example nodes include on and off ramps, merges and splits, and intersections.
Note that controlled access would not mitigate congestion if vehicle-access demand exceeded freeway capacity.
You have probably heard the saying, "wheels are not systems; they won’t get us through the jungle." While these are not his words, you may be forgiven if you thought it was passed down to us by Davius. Had it been, we recognize that he would be reminding us that rather than a jungle (of uncontrolled space and human drivers), wheels (CAVs) need controlled space and SE to enable them to reach the promised land.