Evolution to an Automated Highway System

In the Precursor Systems Analyses (PSA) sponsored by the Federal Highway Administration in 1993, several of the researchers addressed how AHS would be first introduced to the market. The researchers identified several problems to be overcome including driver acceptance and the ability of state and regional departments of transportation to operate and maintain an AHS.(1–3) The researchers concluded that one of the most serious issues is the “chicken-or-egg” problem—which comes first, the AHS highway lanes or the AHS-equipped vehicles? Minimum AHS vehicle penetration for a particular corridor or highway segment is reached when, after conversion of one of the existing highway lanes to AHS, the number of AHS lane users equals the number of manual users of the lane before conversion. It was estimated that this minimum AHS vehicle penetration ranged from 5 to 30% of the total vehicle population depending on many factors such as number of lanes already existing in the corridor, frequency of entry and exit lanes, and average trip distance.