The concept of automated highway systems (AHS) as a means to solve the fast-worsening highway congestion problem has received renewed attention recently. Pros and cons of various mature AHS have been a subject of intense study. However, such discussions are nothing but intellectual exercises unless the issue of how to evolve the current highway systems towards these mature AHS can be resolved. There exist a large number of different possible mature AHS. The additional dimension of evolution leads to an even larger number of possible evolutionary scenarios. This paper proposes an approach to defining evolutionary scenarios and illustrates it with an example.
H.-S. Jacob Tsao. "Stage Definition for AHS Deployment and an AHS Evolutionary Scenario" PATH Research Report (1996).