This report summarized the results of several ITS evaluation projects in the city of San Antonio, Texas. San Antonio had a relatively extensive implementation of ITS prior to this study and, consequently, the incremental benefits experienced in San Antonio through expansion and additions to the existing system may be somewhat smaller than the benefits that could be achieved in areas with little prior implementation of ITS.
Improvements to elements of San Antonio’s traveler information system included the installation of In-Vehicle Navigation (IVN) devices in vehicles operated by public agencies in the San Antonio area. The IVN devices provided navigational assistance, incorporating information on congestion, incidents and railroad crossing status when planning trips.
Focus groups composed of drivers of vehicles equipped with the units indicated that the drivers most satisfied with the system were those that frequently drove different routes each day. Drivers often asked to drive to unfamiliar parts of the metropolitan area, such as paratransit drivers and police investigators, seemed to get the greatest benefit from the system. Overall, public safety representatives indicated that with improvements to the method for entering destinations, the devices could be helpful in reducing response times of emergency vehicles. Public safety representatives did indicate that, with improvements to the method for entering destinations, the devices could be helpful in reducing response times of emergency vehicles. As implemented in San Antonio, however, users complained of the difficulty in inputting destinations easily. Sixty (60) percent of users did report that it was easier to find unfamiliar addresses with the devices, that they saved time and felt safer to use than paper maps. Paratransit operators found the devices very useful and some operators now refuse to take out buses that are not equipped with the system.
The San Antonio project also included a demonstration implementation of a telemedicine system, known as LifeLink, allowing video and teleconferencing between emergency medical technicians (EMTs) and doctors at nearby hospitals. The system allowed doctor’s to see video images of the incoming patients and provide advice to the EMT in the ambulance on providing care en-route to the hospital. Though the system had no impacts on the measures of delay or energy consumption, significant safety impacts are likely if the system is applied in rural areas. As applied in an urban area, the short transit time to the hospital limited the additional benefit of LifeLink. EMTs were very satisfied with the system, though doctors had concerns with the system, especially since it required them to leave other tasks at the emergency room.
The final component of the San Antonio deployment initiative was a system using volunteer private vehicles equipped with radio transponders as probes to determine travel times along area roadway segments. Over 40,000 people volunteered to use the tags on their vehicles, indicating strong support for the project.
The evaluation reports contains several conclusions and recommendations drawn from the results above, and discussions with various stakeholders within the projects:
- Integration with existing system components can also significantly reduce implementation costs. The LifeLink project would have been considerably more expensive without the use of the existing roadside fiber-optic lines installed for the freeway management system.
- Emergency telemedicine can save lives and reduce treatment and transportation costs. A number of institutional and technical issues must be addressed in order to maximize these benefits.
- Vehicle probes offer a potential means of offering travelers the additional arterial information they desire. This will only be possible if a significant market penetration of probe vehicles can be attained.