Advanced Transportation Optimization Systems (ATOS) By Andrew Andrusko Undergraduate Student Student in Civil Engineering, Urban & Regional Studies, Social Studies, Geography, Geology Programs Minnesota State University Mankato Abstract With the advent of wireless technology over the past decade society has seen a number of new and innovative applications in industries outside of the traditional field of electronics. Another major innovation has been the introduction of systems engineering and analysis into the field of transportation engineering. This proposal seeks to define a potential combination of technologies to create an effective traffic management system with the main goal of increasing potential capacity and flow rate. The system will utilize wireless DSRC or Dedicated Short Range Communications to provide a number of backbone features. These benefits will stem from the interconnectivity of vehicle data into information systems for analysis and automation.
Introduction Over the past several decades transportation professionals have come to realize that induced demand has overcome the ability to provide enough capacity to satisfy all current and future needs. Thus a new approach, a new system, is needed to increase the performance of existing transportation to better meet demands. The scope of ATOS is very similar to the concept of ITS or Intelligent Transportation Systems as it is a collaboration - an umbrella of applications. The most important application of this technology is in transportation thus this proposal will discuss a potential framework concept and analyze the possible benefits of implementing such a system. ATOS is Traffic Management ATOS or Advanced Transportation Optimization Systems is a grouping of possible uses of data derived from DSRC sensors. The beauty of this system is in the capability to receive, record and analyze active data from road users continuously- in real time. To that end the use of real time data from a DSRC sensor system can be used to provide a very effective solution toward optimizing and managing traffic. Traffic management is not a new concept by any means. A number of active transportation management systems have been proposed and implemented over the years. For example, the mainstay of many active traffic management systems today is the use of camera systems to determine traffic flow and performance in real time. Another proposed method was to utilize live remotely sensed images to determine traffic flow. Similarly, Google has integrated a data system which links real time data from users portable navigation systems to estimate travel times. These systems require continuous real time data to accurately estimate travel times and allow quick response to crashes. They do not provide a high level of accuracy that a DSRC system could.
The use of DSRC effectively nullifies the need to have passive methods of detection such as camera networks. Each transponder can effectively and more importantly accurately communicate geospatial information such as location, speed, and direction without the need to have a camera or in pavement sensor. One very important component will be that ATOS will operate with an integrated backend GIS or Geographic Information System database. Operators from traffic management, public safety officials, law enforcement and emergency response will all be able to access a central source of information. Each application will be able to utilize software which will cater to their needs. This information, for example, can be relayed into a traffic management model to determine and actively alter signal timings on a broad scale (such as an entire city during peak traffic) to most effectively meet demand through automated network optimization. Ramp meters and signals could be utilized more effectively through integration with the DSRC traffic management model. Thus this also reduces the need to use ALINEA and fuzzy set algorithms in the timing and automation of ramp meters and signals. Queues and driver wait time at ramp meters would be significantly decreased to the maximum possible due to this optimization. The important external benefits of optimizing traffic flow and capacity are reductions in travel time, increased level of service, fewer emissions and thus more effectively increasing the level of sustainability in our highway system. Since the overwhelming theme of civic services has focused on how to create a more sustainable society this system provides a very unique opportunity to increase the operational efficiency of all transportation networks by reducing congestion. This in turn affects every member of society that is a user of transportation.
Figure 1. The ATOS system relies on a flexible backbone structure, shown here, the DSRC circuitry is installed in each vehicle allowing data to be to transferred through infrastructure such as stoplights, light poles or as a standalone structure. This data is relayed into a centralized database which is then available to end users such as traffic managers. Integration and Future Integration with existing autos would fairly simple; the past decade has also seen a rapid increase in the quantity and complexity of electrical systems being included in the design of automobiles. Many freight companies already use a form of geospatial tracking and analysis on their trucks. Federal law requires all trains to have a similar system on board. Thus the addition of a universal DSRC system would need to utilize power as any other electrical component in a modern day car either from the battery or directly from the alternator. Additionally, the DSRC circuits could be used in transit systems. One application would be to install these on conventional buses to provide real time information to users and to provide pre-emption for BRT systems.
This information could at some point be used to effectively convert our analog traffic into a digital type network in which each car is spaced at a set distance determined by the sensor network and thus could travel at the maximum design speed. This is the very technology that is being used to develop the famous Google Car system in California. Since the adoption of technology is a slow and methodical process this later possibility is something that could be implemented in the foreseeable future. Figure 2. The future of transportation will likely rely on increasingly complex technology to address the various needs of users. This may one day include an inverse strategy to optimize traffic flow by enforcing strict spacing to form platoon formations. Thus essentially creating a digital like road network.
ATOS Improves Traffic Safety The second major theme that goes hand in hand with traffic management is that DSRC systems can provide increased levels of traffic safety. An accident could be reported much the same way the commercial service OnStar now operates with automated crash reporting and response. Response times would be reduced and could be easily integrated into innovative ITS crash response systems such as CrashHelp system developed by the University of Minnesota. Network events (accidents) could be recorded and analyzed with more efficiency and less duplication through the use of a single integrated database. Many of the benefits of automating traffic management also increase traffic safety. For example, a reduction in platooning can reduce the incidence of bottlenecks and delays that contribute to crashes. Since almost all vehicles will utilize the DSRC system each individual vehicle will form into a hive or cluster mass that acts as one single network. This hive concept has been termed vehicular ad hoc networks or VANETS. This allows traffic administrators to ensure operation on all highways with high AADT. Since these highways are also the major concern of congestion this will allow simultaneous optimization across the entire system whether it is a limited city block, a Metropolitan Statistical Area or even an entire state. Weaknesses and Vulnerabilities One major disadvantage is that such a system will require significant security measures. Although this proposed system does not alter the control over the individual automobile it may have civil repercussions. For example, an agent could hack into the system and create a distraction by creating a gridlock function or false crash incidents. This vulnerability already exists to a certain extent; existing traffic management operations could also be hacked. Thus the level of security would need to match the current information security practices on a much broader scale. A number of research papers have been published on the concept of automated vehicle systems and possible solutions to reduce the risks involved by members of the Institute of Electrical and Electronics Engineers. In terms of operation the DSRC networks have few weaknesses with low latency, and high link reliability.
Figure 3. Existing roadways would benefit from optimization efforts to reduce heavy congestion. The use of DSRC could also provide information for dynamic message signing (DMS). Evaluation of Existing Systems One similar concept system was developed in collaboration with existing industry partner IBM called the Smarter City Intelligent Transport Solution. This type of system has been implemented in Stockholm as a method traffic congestion pricing and in Singapore as method of network analysis. IBM has stated in Delivering Intelligent Transport Systems Driving Integration and Innovation that one of the important goals was how to utilize geospatial transportation data to the end user. ATOS attempts to fill this function. Tolling One final advantage that a DSRC system could provide is an automated tolling system for individual states. An example of this type of system has been implemented in Minnesota and introduced in HOT lanes.
Conclusion ATOS represents a large improvement in the field of transportation both in terms of service to the end users and in terms of operations. The intent of this concept was to develop an understanding of a possible systems approach to integrate the DSRC technology into a true real time transportation system. It provides a viable cost-effective improvement across the spectrum of concerns. It maximizes capacity, traffic flow through optimization and improves logistics and traffic safety through integration of data. The by-products of these efforts will be a decrease in emissions and increase in the level of sustainability. Coupled with other new developing technologies such as electric vehicles, dual modular transportation systems, and high speed trains this can provide better quality of life for all. Figure 4. Interoperability with various automobiles and modes will increase our knowledge of how to best approach transportation management.
Addressing the Criteria: Feasibility & Prudence: Given the extreme cost of congestion and traffic accidents this system will reduce operating costs for travelers. The cost of ensuring security will be balanced with an increasingly technological society. Production costs will be reduced be partnerships with manufactures. The economy of scale will in any case would significantly reduce production costs as well. Additionally, this system provides reductions in environmental pollution to which there is no empirical method to determine the real monetary benefit at this time. Thus such a system is both feasible and prudent. Potential for Widespread Adoption: Almost all automotive manufactures include electrical systems in their production models thus it will be very easy to develop a universal DSRC circuit package. Older systems could run directly on battery power. Advanced autos could use electric power from electric motors or solar power. So this concept is very versatile and adaptable. It would especially useful for high demand BRT and conventional bus systems. Innovation: This systems concept plan is unique in its attempt to span motor modes of transportation and not just change the red light but to create an optimal highway system that changes all of the lights. Social Benefit: This is the most important aspect of this concept: the benefits to society. Travelers would experience less congestion, fewer wait times, higher possible travel speeds and increased response to accidents and emergencies. Transit users could benefit from real time information and stoplight pre-emption. Society would benefit from the reduction in emissions caused by congestion. Sustainability would be incrementally improved across the board since the main source of carbon emissions is from automobiles.