Proof of concept (PoC) testing of vehicle infrastructure integration (VII) technology is continuing in Southeast Michigan, but emphasis there and elsewhere on VII and vehicle-to-vehicle (V2V) technology (Fig. 1) has largely shifted from mobility to safety.
The Michigan system, developed by the Vehicle Infrastructure Integration Consortium (VIIC), includes on-board hardware installed in test vehicles, roadside equipment along highways and at intersections, and a backend server system. Vehicles communicate with roadside equipment via 5.9 GHz DSRC (dedicated short-range communications).
“The PoC testing focused mainly on mobility applications like in-vehicle signage,” said Roger Berg, vice president of wireless technology at DENSO International America. “The system fulfilled that requirement, but the effort was based on nationwide deployment of roadside hotspots. In the past year or so there have been a lot of changes in the economic status of the U.S. and availability of federal funds for such a plan, so the Department of Transportation (DOT) decided to take a step back and see if those needs can be met in other ways.”
“The U.S. DOT did a thorough evaluation of DSRC in cooperation with the auto industry,” noted Steve Underwood, director of transportation and information systems planning at the Center for Automotive Research (CAR). “Everyone was together on that program. Outside of that, the commercial market is heading in all sorts of different directions. Intelligent transportation is going to happen one way or another, but how, and how fast, and who will be the first to profit, are all open to question.”
Efforts are under way to answer those questions. MARK IV IVHS developed a dual-mode antenna (Fig. 2) that combined 5.9 GHz DSRC and GPS for the VIIC PoC test in suburban Detroit, as well as a VIIC-sponsored parking systems test near Chicago. The firm's compact omnidirectional antenna, flush-mounted to the vehicle roof, has attracted significant interest from automakers, according to IVHS chief technology officer Richard Turnock.
In a project known as GEMS (Group Enabled Mobility and Safety), research teams from the University of California, Berkeley; California PATH (California Partners for Advanced Transit and Highways), and the University of Utah are working with NAVTEQ on an Internet-based system that can deliver alternate routing information to cell phones as a way of helping commuters avoid traffic jams.
In June the U.S. Department of Transportation and the California Department of Transportation (Caltrans) announced a $12.4 million partnership program as part of the DOT's SafeTrip-21 (Safe and Efficient Travel Through Innovation and Partnerships for the 21st Century) initiative.
The DOT's initial vision for VII called for deployment of as many as 400,000 roadside transponders to communicate information to and from motor vehicles. That would have required significant public sector investment, but SafeTrip-21 will explore near-term possibilities that do not require extensive infrastructure, as well as business models that can support widespread VII infrastructure deployment for collision avoidance and other safety-critical concepts.
The SafeTrip-21 partnership in California will test GPS-equipped cell phones and personal navigation devices (PNDs) from up to 10,000 volunteer commuters and transit vehicles transmitting data to traffic management centers from roads in a 200-mile radius. The test will include trip planning and traveler information, safety advisories, on-board displays of commuter rail and transit bus connections, electronic toll collection, and parking reservation and payment services. The partnership is also expected to establish a national test bed for a VII system that uses Wi-Fi as well as DSRC to alert drivers to unsafe conditions.
Partners in the project include California PATH, California Center for Innovative Transportation (CCIT), Nokia, NAVTEQ, Metropolitan Transportation Commission, Santa Clara Valley Transportation Authority, and Nissan.
DENSO's Berg said that firms in the U.S., Europe, and Japan are cooperating in VII and V2V development. “The technology may not be exactly the same, but it will be harmonized,” he said. “Everyone should ‘speak the same language,’ and then car companies can differentiate based on HMI (human-machine interface) and how the driver is warned.”
In the U.S., SAE J2735 (Dedicated Short Range Communications Message Set Dictionary) will support interoperability among DSRC applications through the use of standardized message sets, data frames and data elements. IEEE 802.11.P defines enhancements to 802.11 for support of intelligent transportation system applications, including data exchange between vehicles and between vehicles and the roadside infrastructure in the licensed ITS band (5.9 GHz). IEEE 1609 includes a family of standards for Wireless Access in Vehicular Environments (WAVE).
The European Union decided last summer to allocate a 30 MHz wide frequency range within the 5.9 GHz band for communication between cars, and between cars and roadside infrastructure, as part of its Intelligent Car Initiative. A vehicle detecting a slippery patch on a road could inform all cars located nearby of the danger if the car were equipped with a cooperative car-to-car communication device. As early as 2011 the EU hopes to see production vehicles equipped with information and communications technologies for reducing road accidents and easing traffic congestion.
In Japan, Nissan and NTT DoCoMo Inc. plan to test an Intelligent Transport System during November and December. The system integrates cellular communications with vehicle telematics and is focused on helping to prevent pedestrian-related accidents. According to Nissan, 30% of fatal accidents in Japan involve pedestrians. The company's goal is to reduce the number of such accidents by half by 2015 compared with 1995.
The Nissan/NTT DoCoMo test involves 500 pedestrians and 200 drivers. Pedestrians will use a special cell phone compatible with the Nissan navigation system in test vehicles. As a vehicle approaches a residential area where blind intersections exist, the driver will be alerted by voice message and screen display when a pedestrian would otherwise be hidden around a corner.
The information server detects data transmitted via GPS to the pedestrian's cellular phone and sends it to the vehicle navigation system, which triggers the alert. Nissan plans to verify that the system will work effectively and to monitor changes in drivers' behavior after they receive alerts.
Toyota InfoTechnology Center has developed road-to-vehicle communication technology that uses both 5.8 GHz DSRC and 700 MHz UHF. The company expects that the technology can make the communication system more redundant by transmitting the same information on the DSRC and UHF waves.
DSRC/UHF roadside units and receivers used in a Toyota InfoTechnology test were manufactured by Mitsubishi Electric Corp. Devices for DSRC and UHF communications as well as antennas and other equipment compatible with both bands were installed in a microbus. The systems were designed with DSRC as the main communication method; however, a decision was made last year to use the UHF band for automotive communications after the termination of analog TV broadcasting in Japan. According to Toyota InfoTechnology Center, UHF waves are more suitable for vehicle-to-vehicle communications than DSRC because they propagate more easily through obstacles.
Earlier this year Honda tested inter-vehicle and road-to-vehicle Driving Safety Support Systems (DSSS) technology on public roadways in Japan. The DSSS are being developed by the Universal Traffic Management Society of Japan (UTMS).
The project uses positional information from communication among motorcycles, automobiles, and road infrastructure to help prevent accidents involving rear-end collisions, collisions between turning vehicles and oncoming vehicles, and collisions involving turning vehicles with vehicles passing on the inside.
Honda conducted public-road tests using Forza scooters and Odyssey automobiles equipped with inter-vehicle communications technologies being developed as part of the Honda ASV-4 advanced safety vehicle.
The Connected Vehicle Proving Center, a unit of the Center for Automotive Research, maintains a signalized intersection testing and proving site for the center's clients and partners. With the support of the Michigan Department of Transportation and the Road Commission for Oakland County, the CVPC test site has two consecutive signalized intersections in the vicinity of important highways and also provides multimodal communications with multiple options for roadside units.
Both intersections include a configurable vehicle communication system that allows spatial information and signal-phase timing to be passed from the signal controller system to the vehicle. The intersections can communicate bidirectionally with the CVPC's network operating center and testing center.
CVPC general manager Udi Naamani said the test site allows CVPC's partners to test communications between connected vehicles and roadside equipment and from connected vehicles to traffic signals.
In July Ford opened a Smart Intersection near its headquarters in Dearborn, MI (Fig. 3). The intersection is intended to help leverage GPS technology and wireless infrastructure-to-vehicle communications to reduce traffic accidents and ease congestion.
Ford's intersection communicates with test vehicles to warn drivers of potentially dangerous traffic situations, such as when a vehicle is about to run through a red light. The intersection is equipped with technology that can transmit a digital map of the intersection, maps of surrounding stop sign intersections and crosswalks, lane-specific GPS location, and traffic light status and timing information.
When the in-vehicle computer receives data indicating a potential hazard, it can warn drivers through visual and audio alerts. The vehicle's collision avoidance system can use that information to determine if the car can cross the intersection safely or if it needs to stop before reaching it. If the system determines the need to stop and senses that the driver is not decelerating quickly enough, the collision avoidance system can issue visual and audio warnings to the driver.
“A vehicle equipped with a collision avoidance system could also act as a traffic probe, and communicate its presence and travel history when it encounters a smart intersection,” said Mike Shulman, technical leader, Ford Active Safety Research and Advanced Engineering. That ability would complement the SIRIUS Travel Link feature Ford currently offers (Fig. 4). Travel Link combines real-time traffic speed and flow data with accident and incident information to allow the user to navigate around congested areas.
Ford, General Motors, Honda, Daimler, and Toyota are working with the U.S. DOT and local road commissions to develop a common architecture and standards for smart intersections. The effort is known as CAMP VSC2 (Crash Avoidance Metrics Partnership Vehicle Safety Two Consortium). “It takes a couple of seconds to establish a cell phone connection, which is okay for alternate routing but can't be tolerated in VII or V2V,” said DENSO's Berg, “so low-latency (<50 ms) will be used to support critical collision avoidance applications.” Berg said DENSO is participating in the CAMP research effort.
CAR's Underwood concurs, “You can do lots of things with a broadband cellular network, but you can't do active safety. Safety applications require very quick identification through a quick exchange of information among unknown participants. It seems best to run hard core safety applications, and also road payment, through DSRC channels, and mobility applications through a 3G cellular network. If we imagine a time in the future when all vehicles have DSRC for electronic tolling, other applications can be added, such as communicating with other cars. If you have it, why not use it?”
Ford's Shulman said CAMP VSC2 has developed and tested a prototype CICAS (Cooperative Intersection Collision Avoidance Systems) for violations, with sensors, processors, and driver interfaces in test vehicles and roadside sensors and processors to identify hazards and issue warnings to drivers via DSRC communications links. It has tested the CICAS prototype successfully at intersections in Virginia, Michigan, and California.
“We may do a larger field trial,” said Shulman. “(Nationwide) deployment is not imminent, but it won't be terribly long, either.” The target cost of in-vehicle CICAS hardware is low. “You just need a DSRC radio, a GPS receiver, which may be in the vehicle already, and processing, which may also be present. We're also looking at radar and camera technologies, but DSRC and GPS would have a big safety impact because they provide 360° coverage. If smart infrastructure technology gets deployed, we want to be ready. We are already working with other carmakers on standards as well as working with the government on what it takes to deploy vehicle-to-vehicle safety applications.”
|California Center for Innovative Transportation||www.calccit.org|
|California Department of Transportation||www.dot.ca.gov/|
|Center for Automotive Research||www.cargroup.org|
|Connected Vehicle Proving Center||www.cvpc.com|
|MARK IV IVHS||http://www.ivhs.com/|
|Metropolitan Transportation Commission||www.mtc.ca.gov/|
|Michigan Department of Transportation||www.michigan.gov/mdot/|
|Mitsubishi Electric Corp.||www.mitsubishielectric.com|
|National Highway Traffic Safety Administration||www.nhtsa.dot.gov|
|Road Commission for Oakland County||www.rcocweb.org|
|Santa Clara Valley Transportation Authority||www.vta.org|
|Texas Transportation Institute||www.tti.tamu.edu|
|Toyota InfoTechnology Center||www.toyota-itc.com|
|Universal Traffic Management Society of Japan||www.utms.or.jp/english/system/dsss.html|
|University of California, Berkeley||www.berkeley.edu|
|University of Utah||www.utah.edu|
|U.S. Department of Transportation||www.dot.gov|
|Vehicle Infrastructure Integration Consortium||www.vehicle-infrastructure.org|