PRISM is designed to address both congestion (through vehicle automation) and petroleum dependency (through guideway electrification).

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Cost-Benefit: PRISM offers a low-cost infrastructure ($3.5 million/ln-mi) by keeping vehicle size and weight low. Recognizing that nearly 90% of commute trips in most urban areas have two or fewer passengers, the vehicle capacity is limited to two passengers. While no GVW limit is given, with a curb-side weight of 1,320 lbs. a loaded weight might be in the range of 2,000 lbs.

Technology Innovation: As with the other Top Tier systems that electrify the guideway, PRISM depends on the successful implementation of numerous technologies in addition to those required for vehicle automation. While electric motors have proven reliable in many applications, they are not used widely to propel automobiles. Potentially more problematic is the method for transferring power from the guideway to the vehicle. The simultaneous introduction of multiple unproven technologies in a new system sharply increases the probability of operating problems and failures.

Reliability is essential to most automated highway system designs. A single automated lane can carry the equivalent of four or more lane-miles of regular traffic. Since most systems do not have any "shoulders" for disabled vehicles, a vehicle failure effectively shuts down the entire highway in that direction until cleared. While all designers have methods for moving such vehicles quickly, the most effective mitigating strategy is to reduce the failure rate so that such occurrences are infrequent enough to ensure better overall flow than off the guideway. Increasing technology innovation compounds risks for vehicle failures that work against system reliability, especially in the early stages of adoption when rapid acceptance is critical to success.

In contrast to the electrified guideway, internal combustion engine (ICE) technology has many trillions of miles of real-time experience on roadways. Focusing initially on ICE products of highest reliability reduces the risk of the market rejecting an automated guideway system for technology failure unrelated to the purpose of vehicle automation. Once plug-in electric cars attain a sufficient level of reliability they can be certified for use on an automated guideway. Proving the reliability of an electrified guideway is more problematic since there is no application that can establish the reliability level other than real-world. The case for taking on this risk up front is difficult to make.

Market Acceptance: PRISM relies on a dramatic shift by drivers to a vehicle whose size and seating configuration is a distinct departure from current preferences. Two-seat vehicles are a miniscule portion of today's auto market. In addition, such a vehicle would have limited use as a general purpose vehicle. While most trips may include two or fewer occupants, the ability to carry four or five substantially increases the flexibility of a given vehicle to accommodate most or all of a car owner's needs both on and off the guideway.

Status: The paper was written by four Ford engineers, three of whom were retired at the time and the fourth has since left Ford. There is no indication of any ongoing activity related to PRISM at Ford or elsewhere beyond the 2003 paper and conference. Also in 2003 three related patents were issued.