IVHS Technology for Improving Ridesharing

by John S. Niles [1] and Paul A. Toliver [2]

A paper from the Proceedings of the 1992 Annual Meeting of IVHS America (now ITS America), and presented at that meeting in Newport Beach, California, May 1992.

Note: This paper presents the professional but personal views of John Niles and Paul Toliver writing as individuals, and thus does not represent the policies or positions of any organization or association. John Niles acknowledges the generous support of the Bellevue (Washington) Downtown Association, Federal Transit Administration, Municipality of Metropolitan Seattle, City of Bellevue and McCaw Cellular Communications toward the development of the ideas in this paper.

Related Web links appearing since the time this paper was prepared:


Conventional wisdom holds that suburban public transportation officials need to wage war against the American love affair with the automobile. A new, more constructive wisdom presented here suggests that public transportation officials try to create an Intelligent Vehicle Highway System (IVHS) application that exploits that love affair. Computerized message processing and portable wireless telecommunications permit the creation of a new mode of public transportation, called here Intelligent High Occupancy Vehicle, or IHOV. This mode combines a high-tech instant rideshare request system with incentives for drivers to invite passengers into their otherwise single-occupant vehicles (SOVs). Flexible single-trip carpooling occurs as opportunities present themselves in the matching system that are safe and convenient for both driver and potential passenger. Phone calls to a friendly computer, which processes voice messages and other information, let people find other people who are also about to make car trips that could easily be combined. IHOV offers a vision that powerful IVHS configurations will cause travelers to park their cars and hitch rides with friends, neighbors or co-workers.


Over the past ten years, a radically new and different vision for public transportation has begun to emerge from research and development activities taking place in the western United States, specifically in Hawaii, Oregon, California and Washington. Funded by federal, state and local governments, this R&D is aimed at designing and deploying a system of computers and telecommunications that would (in association with various incentives and regulatory requirements) cause a large number of private automobiles to become part of a regular passenger-carrying public transportation vehicle fleet. The initiator and still leading participant in this research is inventor and entrepreneur Robert Behnke, now president of Aegis Transportation Information Systems Inc., based in Portland, Ore. This paper expands the vision of public transportation he first described beginning in Honolulu in the mid 1980s, [3] and continued in the California Smart Traveler and Portland Smart Bus projects in which his firm acts as a contractor to government agencies.

The extensions of Behnke's ideas described in this paper have their origin in a program of the Bellevue (Washington) Transportation Management Association called Mobility Innovations, which author Niles administered in its startup phase through the end of 1991 and which author Toliver oversees as a member of the Bellevue TMA board of directors. With support from federal, state and local transportation agencies, the Bellevue TMA in 1991 began designing an operational test of a telecommunications and computer configuration with the goal and potential to double public transportation's market share in the suburbs. This test effort is called Bellevue Smart Traveler, one of the "IVHS Early Winner Projects" listed in the IVHS Strategic Plan. (See Appendix A for further information on Bellevue.) This paper generalizes and extends the concepts of Bellevue Smart Traveler as a way of suggesting to an expanding network of IVHS innovators that there are many opportunities for research and development in support of this new kind of public transportation system. [4]

The suburban transportation market

The North American metropolitan area transportation market is increasingly difficult to serve with traditional fixed-route, fixed-schedule transit, because transportation origins and destinations are becoming more varied and dispersed. More and more Americans and Canadians live or work in the suburbs, usually both. Jobs are spread across a multiplying number of office parks and other employment sites. Residential locations are becoming more scattered as people seek affordable housing, acceptable public schools and fewer neighbors.

The private car reigns in the increasingly suburbanized metropolis. Automobile ownership levels are rising, with one car for each licensed driver becoming the norm. At the same time, the rising auto usage stemming from growth in jobs and residential population is making traffic congestion less tolerable in the suburbs of ever more metropolitan areas. The result of these traffic jams is air pollution, energy waste and unproductive consumption of people's time.

The mode of public transportation with the greatest market share in the United States is carpooling. About three times as many people commute in carpools as use public transit. [5] The importance of pooling as a public transportation mode is at least nominally recognized by the existence of rideshare branches in many transit agencies, such as Seattle Metro.

Still, given the relative success and cost-effectiveness of carpooling, it is dismaying that the management of carpooling is often viewed by transit agency managers (with some exceptions,such as Seattle Metro) as well as the general public as a much lower priority for attention and resources than scheduled bus service. The authors believe that carpooling needs to be given much greater weight in meeting suburban travel needs than is now the case.

At the same time, carpooling needs to be improved to fit better with people's travel requirements. In the greater Seattle region, as well as everywhere else in America, carpooling (and its cousins vanpooling and subscription bus) are organized around serving the daily rush-hour commute from home to work and return, with regular four- or five-day-per-week service scheduled for commuting at the same time each morning and evening. Research by Bellevue Mobility Innovations revealed the need and potential to expand the flexibility of carpooling to meet a wider variety of travel requirements, including irregularly-timed commutes, very short commutes and non-commute trips, all of which are dominated by use of single-occupant vehicles (SOVs).

IVHS technology offers the potential for a dramatic expansion of carpooling. IVHS technology supports the prospect of succeeding in a radically new emphasis in public transportation: shifting emphasis away from adding new bus and train capacity toward finding and using existing capacity, through a system of public technology to increase the average passenger occupancy in the existing fleet of private vehicles that are already being paid for by individual owners. This emphasis on carpooling need not obscure the fact that IVHS technology also offers a variety of opportunities for making bus service more efficient and effective, including the addition of computer-managed, demand-responsive route and schedule variability.


Effective and efficient investment in public transportation improvement requires that government leadership make choices about system characteristics in order to meet the demands of the market. For example, in choosing between expanding the number of buses or building a light-rail train line, planners need to consider the relative attractiveness to consumers of riding bus and rail, and also what each alternative offers in average waiting time, average door-to-door travel time and variability in travel time and waiting time. Of course cost needs to be considered also.

Similarly, in deciding how to improve public transportation through investment in IVHS technologies, design choices are also called for. One key choice is whether to overlay telecommunications and computers onto existing public transportation systems in order to improve performance, or to use IVHS technologies to create a totally new public transportation system. IVHS for public transportation - generically called Advanced Public Transportation Systems (APTS) by the Federal Transit Administration - offers many choices for vision and technology.

A public transportation system is a specific type of service delivery system. In general, both inside and outside of the transportation industry, the most effective and efficient service delivery systems are those that are reengineered and molded around the capabilities of telematics (telecommunications and computers in combination). Examples of transportation services that are characterized by their telematic support systems include airlines and overnight package delivery. Outside of the transportation arena, banking and printed information media (newspapers and magazines) are being revolutionized by telematics. Two service industries that are on the verge of being revolutionized by computers and telecommunications are education and health care. The role of computers and information technology in changing the essence of service delivery are well described by such popular authors as Alvin Toffler, [6] Peter Drucker [7] and Stan Davis. [8]

With respect to metropolitan area public transportation, IVHS offers the possibility of many alternative investments, ranging from making incremental improvements in traditional fixed-route, fixed-schedule bus service to defining radically different, demand-responsive modes of service. Incremental improvements include electronic fare collection and bus location monitoring. Radical changes include restoring the failed promise of demand-responsive dial-a-ride and enlarging the potential of carpooling. This paper describes potential IVHS-based investments on the radical side.

In parallel with the planning described in this paper, a public transportation vision for the central Puget Sound Region (Everett, Seattle, Bellevue, Tacoma and environs) is now emerging - a multimillion dollar planning effort called the Regional Transit Project. While the majority of this project's attention and spending focus on the phased implementation of a 150-mile exclusive right-of-way, fixed-guideway rapid transit system, the project's secondary emphasis is on better bus service and ridesharing throughout the region. This secondary emphasis is where the planning started by Bellevue TMA Mobility Innovations can make near-term improvements in the region's public transportation system - in fact, much sooner than the year 2000, the earliest date that fixed-route rapid transit is likely to start operations.

Federal Transit Administrator Brian Clymer holds out the goal of doubling public transportation ridership over the next twenty years, [9] where public transportation includes all alternatives to the single-occupant vehicle. Bellevue TMA Mobility Innovations came up with the following conceptually simple method of doubling public transportation use from its present level of approximately 20 percent to 40 percent: Find a way to cause one SOV driver out of eight to leave her/his car parked and ride with somebody else already going to the same destination. Through IVHS, develop a technical means for the drivers of the remaining seven SOVs to find out about friends, neighbors and co-workers who need rides. Give SOV drivers trip-by-trip options and incentives to pick up and drop off other travelers having coincidental travel needs. If only one out of seven of the remaining SOV drivers would voluntarily provide a ride to a ride-seeker, the mode split would change to 40 percent HOV. How this can be done is explained next.

A public transportation response: IHOV

This paper proposes the creation of an entirely new public transportation system called Intelligent HOV, or IHOV for short, to serve a segment of typical urban/suburban travel demand that is now largely met only with SOV travel.

IHOV would be a new "public transportation system" of technology, institutional arrangements and incentives that encourages private vehicle owner/drivers to carry additional passengers on a voluntary trip-by-trip basis when it is convenient, safe and worthwhile to do so. This "public transportation system" expands the conventional meaning of public transportation from a fleet of vehicles on fixed routes and schedules to a flexible. demand-responsive system using vehicles that are already on the road every day.

Conventional dial-a-ride transit has cost problems - the public costs of paying drivers and operating vehicles. (Vehicle operations, of course, include the cost of purchasing, maintaining and insuring vehicles, in addition to buying fuel.) IHOV is based on the idea of private citizens - responding to regulatory incentives and restrictions - voluntarily putting their private vehicles and their driving time into public transportation service for a small but motivational level of compensation.

IHOV is also based on the notion of coordinating the coincidental travel requirements of people who would share a ride in the same vehicle if only each knew that the other were making the journey. For example, members of a test group of commuters into downtown Bellevue expressed a willingness to make a five-minute diversion off their regular route occasionally to pick up a co-worker, if they knew about the need at an early enough time. Most neighbors would be willing to share a ride to the airport if they were going out on the same flight and each had a way of returning from the airport after the flight home.

One likely requirement of a driver responding to a ride request is having some affiliation or common interest with the ride requester, and vice versa. Affiliations include relatives, friends, co-workers, church members, club members and neighbors. Most people have multiple affiliations that could be used as criteria for matching through computer-based management. An example of computerized affiliation management is the MCI telephone company's Family and Friends program, which keeps track of affiliations all across America and provides calls within groups of affiliated people with long distance calling discounts.

IHOV assumes that round-trip travel can be factored into a series of one-way trips. The requirements and options for a return journey are often easier and more flexible than the originating journey. An originating trip, say from home to an office building, often has time constraints and starts from a point where other travelers are not present. A return trip is more likely to start from a point where other people are gathered and where a means of return transportation is available. Consider getting back from a meeting, compared to getting to a meeting. As another example, a local trip home from an airport is often easier than a ground trip to an airport, because time pressure is off and there is usually an ample supply of transportation services at the airport ready to go. This asymmetry is exploited in the successful "Guaranteed Ride Home" programs operated by transportation management associations.

Appropriately designed and technology-supplemented IHOV offers the following characteristics:

Can be brought online in the mid 1990s, since it can be implemented as an evolutionary extension of existing vanpool, carpool and SOV modes of transportation.

Meets many travel needs of people, because it can go to all the places where they live and where they want to travel, whether work, school, shopping or elsewhere.

Is relatively inexpensive to implement and operate, especially in comparison with the cost of building new concrete and steel fixed-guideway rapid transit.

Is attractive to some travelers even in direct competition with rapid transit, as evidenced by the casual, instant carpooling that serves thousands of people daily in rail and express bus corridors leading into San Francisco and Washington, D.C. [10]

Provides the basis for an evolving transportation system with the flexibility to change and match presently unanticipated characteristics of daily life and associated trip-making beyond the year 2000.

Can be configured with IVHS technology into a door-to-door, demand-responsive mode of travel with little need for intermodal transfers.

Will contribute to emerging North American air quality and energy efficiency objectives, assuming reasonable technological and legislative progress in mandating alternative fuel (e.g., electric) vehicles over the course of the next twenty years.

Will contribute to emerging congestion-management goals, assuming foreseeable application of IVHS technology to HOVs and to HOV highway lanes.

Is compatible with a wide range of land-use patterns, even though - like all shared vehicle use - it works best with higher density origins and destinations.

Provides a system for organizing carpools outside of rush-hour commuting trips and with non-commuting populations such as senior citizens and daytime shoppers.

The automobile is now an integral part of our social and economic culture. IHOV represents an acknowledgment that the lifestyles and land development patterns of North America have been shaped by the automobile for over half a century. Significant changes in "auto-dependent" lifestyles and development patterns of North America are going to be slow in coming, even if such changes are motivated by political leadership, a new oil shock or global warming. Given the "head start" and growing market share of automobile usage, public transportation managers should not view the automobile as problematic competition, but rather as an opportunity for expanding the capacity of public transportation. North Americans stand a better chance of success in public transportation in the years ahead through fully including the automobile in proposed public transportation system enhancements.

If public transportation managers can help the SOV driver to feel good about being a part of public transportation by becoming an IHOV driver, then we have an additional strategy for expanding the people-moving capacity of public roads and highways. We are suggesting that for some travelers, adding a passenger to some of their private journeys is less inconvenient, and less disruptive to their lifestyles, than leaving their cars parked and taking public buses.

IHOV systems technology

The overall IHOV ridesharing system that we envision would consist of several subsystems:

1. The keystone is a constantly operating ride request/reservation computer system that transmits qualified short-notice travel needs to automobile drivers who are part of IHOV as screened volunteers. The system lets drivers conveniently learn of the travel needs of friends, neighbors and co-workers who have pickup points, destinations and schedules that are feasible to serve with volunteer ride offers. Potential riders willing to be picked up by IHOV drivers would phone in to the computer to enter requested pickup points and times with TouchTone buttons and spoken commands. The system provides drivers with information needed to divert, find and serve these needs. The system would also quickly set up direct voice telephone communication between the driver and the potential passenger via mobile telephone.

2. Another requirement is a transaction monitoring and accounting system that generates data for managing IHOV and for becoming the basis of a cashless fare collection system of compensation from riders to drivers.

3. A critical subsystem, described later, is a multi-layered security system that allows both drivers and riders participating in IHOV to feel safe and be safe.

4. Also, an advanced traffic management and traveler information system serving IHOV drivers and passengers would be an important incentive, because it would give IHOVs an information advantage over SOVs in finding the fastest routes, or even just knowing what lies ahead in urban traffic. This system would provide special driver information and traffic control improvements exclusively to IHOV vehicles, buses and other forms of public transportation through mobile telecommunications.

5. A "Mobility Manager" system [11] would provide consumers with information about and access to not only IHOV but also other forms of public transportation, such as trains, buses, taxicabs and jitneys, as alternative means of travel when an IHOV car is unavailable for a particular trip.

We envision that wireless telecommunications integrated with voice and data message processing would be the main technology tying these subsystems to each other and to drivers and passengers.

The emerging cellular telephone system, which includes voice mail, provides a good technology platform for IHOV. All participants in IHOV, passengers and drivers, would have small personal phones, although any desk phone or phone booth would also be a means for interacting with the computer. Personal pocket-sized phones carried at all times by IHOV passengers and drivers would allow for coordination of ride requests and offers from all locations at all times.

The voice mail that is part of cellular telephone service today is primarily used for recording messages when the phone is not answered. Under IHOV, the voice mail system would be enhanced to provide the place where potential passengers leave ride requests and where drivers obtain screened, qualified, reasonable ride requests with the information to serve them.

Requests for rides in voice mail phone messages would include a voice component (spoken by the requester) and a data component (where the data is generated through TouchTones or automatically). The data component could include codes that indicate when drivers are planning to start their journeys. For example, users could enter 7:30 a.m. by pushing the buttons 730A on any telephone.

Matching occurs after voice/data message ride requests find their way after sophisticated but very fast computer processing to "voice mailboxes" of multiple eligible vehicle drivers who could feasibly provide a ride. Drivers of IHOVs willing to take passengers would hear requests and make offers of rides that would not divert or delay them unacceptably. Available offers of a ride are communicated back to the requester either immediately or during a callback. After a driver accepts a passenger's request and creates a reservation, the request message is erased from the voice mailboxes of other feasible drivers. Also, offers that drivers withdraw (say, because their car is now full with other reservations) are also deleted from the system.

Ubiquitous wireless telephone service is no pipe dream. As of the end of 1991, there were 7.6 million cellular telephone subscribers in the United States, with an annual growth rate of 46 percent (6,400 new subscribers per day). There are new forms of wireless phone service that offer the potential for dramatically lowering the cost of service, which is going to fall in any event. Serious observers and analysts believe that wireless voice and low-speed data service is likely to become universal early in the next century. Certainly the cellular telephone industry is working hard to make this vision come true.

One concept developed by Bellevue Mobility Innovations is that of a monthly transportation allowance, a fixed monthly quantity of cellular telephone airtime usage, which would be provided at government subsidized rates to IHOV participants for the purpose of coordinating shared rides. Such mobile telephone usage, used by drivers and passengers for coordinating IHOV, would be a part of a region's public transportation system.

Finally, we feel that mobile communications technology in the hands of both drivers and passengers is important in solving the problem of drivers quickly and conveniently locating the requested pickup points of ride requesters. Drivers getting help in maneuvering through suburban street mazes in residential subdivisions and office parks may be a key to IHOV success. A related use of mobile communications lies in drivers making riders aware of unanticipated delays in the estimated time of pickup.

Our long-term operational technology vision for IHOV looks like this:

1. A mixed government-business technology deployment program causes IVHS electronics to be installed in private passenger vehicles belonging to willing I-HOV participants. This package of electronics includes automatic vehicle location, electronic in-vehicle map displays, cellular phone and security card reader.

2. Public transportation agencies, telephone companies or other information service providers maintain a ridematch computer that carries out the driver-passenger matching process. IHOV users would access this computer through any telephone, whether traditional voice-only, video-screen-equipped or wireless. Telephones used frequently for IHOV would have special function keys for such common requirements as providing a location for a pickup. A potential passenger for IHOV phones the computer and enters current location, desired destination and desired pickup time. The current location of the caller may be entered manually by TouchTone buttons and voice recognition or automatically through Automatic Number/Line Identification (ANI/ALI) that identifies the location of the caller's telephone, or a Global Positioning System (GPS), which relays the exact latitude and longitude coordinates of the caller.

3. The ridematch computer transmits compatible rider pickup opportunities to IHOV participant vehicles, which show up in the driver's voice mailbox or as dots on the in-vehicle electronic map. Eligibility for a match includes use of real-time computerized distance calculations that compute (1) how close a driver's expected routing will come to a potential passenger pickup point and (2) how close a driver's routing or destination is to the requested destination of the passenger. The ride match algorithm is likely to be some sort of dynamic "fuzzy logic" [12]sorting of ride-request messages through various filters that take into account driver and passenger preferences and restrictions. When a match is fulfilled, the ride request drops out of the system.

4. The IHOV driver and the prospective passenger establish voice communications as driver confirms ride offering and approaches pickup point. Voice communication permits the passenger and driver to share directions and visual identification information.

5. The IHOV driver and the passenger use TouchTone-generated personal identification codes or their respective electronic smart cards to establish positive identification, record the shared ride transaction and maintain positive security for both parties.

6. Each shared-ride transaction triggers available IVHS incentives, including exclusive traffic information reports, preferential road and parking prices and financial incentives.

Many questions and some answers

There is no doubt that stopping to pick up and drop off a passenger as an addition to what would normally be a solo journey is an added inconvenience. The inconvenience needs to be balanced off with a workable, motivating set of incentives.

Potential incentives to IHOV participant drivers include authorized access to diamond lanes, cheap and reserved close-in parking, toll reductions, employer-provided incentives, access to exclusive traveler information services, subsidized IVHS in-vehicle electronics (e.g., video maps) and cash compensation payments.

A key question about motivation to use IHOV is travel time, a primary criterion in decision-making about travel mode: Will door-to-door travel times for IHOV passengers, and for IHOV drivers, compete sufficiently well with door-to-door travel times via SOV self-drive? We think so, but simulations are needed.

Questions about these incentives for drivers include:

> Can drivers be provided enough incentive to take the extra trouble to call in, be diverted twice (to pick up and then to drop off a passenger) during a trip and have their traditional SOV privacy disturbed?

> Can IHOV driver/owners who have additional time and dollar costs in providing rides be compensated sufficiently?

Potential incentives to IHOV riders include not having to drive and not having to park a vehicle, both of which can save money and time. If the IHOV journey can use diamond lanes, then faster journey speed may be available. A sufficiently active IHOV public transportation system may well allow people to give up having a second or third household vehicle, which is likely to be worth thousands of dollars annually.

Questions about these incentives for riders include:

> Will potential riders be motivated to give up the flexibility in having a personal self-drive vehicle normally accessible at the IHOV destination point?

> Is the "going back" journey going to be as easy-to-make by passengers via IHOV as the "getting there" journey?

> Is there a level of compensation to be paid by IHOV passengers to drivers that is sufficient to motivate drivers but not so high as to deter potential riders?

IHOV, like all public transportation service, will operate under a set of public expectations that determines service demand levels and service performance.

> Under what circumstances (time-of-day, geographic location, road networks, population density, employment location density and transportation destination density) will there be a sufficient supply of driver/owners willing to make assured rides available to passengers?

> Can peak-load performance be sufficiently assured in the telecommunications system that glues IHOV participants together? The computerized matching of drivers and passengers must be able to process under heavy transaction loads.

> Under what circumstances would the supply of IHOV seats provided by volunteer drivers be so limited that the service would require contract taxis as supplemental providers?

> Can a sufficient supplemental means of travel be flexibly provided to passengers who cannot quickly find a willing and able I HOV driver/owner to provide a ride?

Most importantly, we need to look at how to avoid discomfort and danger in voluntary instant carpooling. This is the most common issue raised by those who are hearing about IHOV for the first time.

> Sharing a vehicle with a relative stranger, even if that stranger is a neighbor or co-worker, creates a host of issues that need to be faced. IHOV creates close encounters between people who might not know each other very well. The same is true of all public transportation modes, such as airline and bus travel. But on traditional public transportation vehicles, there is usually the security provided by the presence of other passengers and of uniformed crew members including the driver and sometimes others. There may be no such other help around in an IHOV encounter.

> The fact of close encounters in ridesharing causes a litany of potential discomforts and dangers in the consideration of I HOV. The list ranges from one occupant impolitely talking too much or asking too many questions, all the way across the spectrum to physical assault. A complete list of potential problems is given in Appendix C. Evidence from casual carpooling in San Francisco and Washington, D.C., suggests that risks may be manageable.

> While a good deal more research and experience is required before judgments can be reached on how these potentials will play out in IHOV practice, we have begun to sketch out some responses in the design of IHOV. One response we are planning is a sophisticated security system that protects both drivers and passengers from the most dangerous outcomes of sharing rides on short notice. We propose that IHOV provide protection from unwanted driver-passenger matching through a technology-based security system with five levels of protection:

  1. Certified and positively identified drivers.

  2. Certified and positively identified vehicles.

  3. Computer-coordinated affinity grouping to let friends, neighbors, and co-workers coordinate travel and ride with each other while screening out others.

  4. Electronic, computer-assisted identification of passengers by drivers, and drivers by passengers, just prior to the point of getting in a vehicle together. This identification would encompass both personal identification numbers (PIN codes) and wallet-sized identity cards. The ID cards might eventually be "smart cards" capable of data processing and storage and useful for management of the IHOV mode in several respects.

  5. Electronic, one-button panic alarms for use by drivers and passengers in summoning police.

> Sharing normally private vehicle interior space with other people reduces privacy, by definition. Furthermore, the IHOV telematic systems that provide security as just outlined, and others which require the collection of data on drivers and passengers, all have the clear potential to reduce personal privacy. Whether these privacy reductions can be mitigated through other benefits and qualities of IHOV is an open question. There is a partial analogy with the screening that passengers and luggage have to go through before being allowed aboard a commercial airline flight. The reduction of privacy is now judged to be well compensated by the increase in safety.

Finally, we need to note two points of potential political opposition to IHOV:

> The first is opposition from members of the public who do not like some aspect of IHOV and would prefer that attention and resources continue to be focused on traditional public transportation systems of buses and trains. This may include those environmental activists who oppose all expansions in the functionality of private automobiles.

> The other resistance might come from people in the older public transportation modes who drive for a living and the organizations which employ them, who may fear that IHOV may work well enough to eliminate certain bus routes.

People at both these points of possible resistance need to understand that the main target market for IHOV is the driver of the single occupant vehicle in low-density suburban locations where traditional transit service is ineffective. Getting a few more of these travelers to double up on some trips is going to be good for the environment. If IHOV also means that some grossly underused transit resources can be redeployed to improve service frequencies along higher density corridors, that would be good for the environment and transit productivity at the same time.

Integration of vanpool and bus service

The primary focus in this paper is on exploring a way of using the massive untapped passenger capacity of private automobile SOVs that are already on the road in the North American surface transportation system. This massive untapped capacity provides the greatest opportunity for a payback from the technical investment needed to implement IHOV.

However, we stress that vanpools and small transit buses can and should also be integrated into the total fleet of Intelligent High Occupancy Vehicles. Incorporating vanpools and small buses into IHOV could either be a first implementation step or an effort parallel with the revitalization of carpooling. Vanpools and small buses would be used similarly to carpools, but with the added challenge of managing their diversion from their regular fixed routes and pickup patterns. Managing this portion of the fleet would probably require the addition of an automatic vehicle location device to each vehicle, generating geographic position data for dispatchers and customers.

How to proceed with implementing IHOV

There are two development paths contemplated for rollout of IHOV: enhancement of carpooling and vanpooling, and the addition of route-deviation flexibility to scheduled service with small buses. Both of these paths would begin with the use of vehicles that are already in the HOV mode, but which typically have additional capacity that could be partially filled.

The capital and operating resources to test, modify and deploy an IHOV system can be obtained from three sources: In-kind contributions from private corporations developing IVHS products for the world market; IVHS funding from the Federal Transit Administration and Federal Highway Administration of U.S. Department of Transportation and from state departments of transportation; and funding reprogrammed by governments from less-effective, traditional modes of public transportation.

At the same time a variety of incentives already being implemented in major urban markets like Seattle can be fit into the IHOV framework. The inclusion of HOV preferential parking spaces, HOV lanes, recognition and cash incentives from employers or any other type of motivation of SOV drivers to participate increases the probability of IHOV succeeding.

The likely most effective deployment of IHOV would be coverage of geographic areas when and where regular scheduled bus transit service is least efficient - for example, in suburban low-density areas at any time and higher-density areas on weekends. To the degree that IHOV can be made safe, it may also be an effective and efficient mode of service for low demand night hours.

In the Seattle area, IHOV is likely to evolve first through enhancements to existing rideshare agency carpool/vanpool programs, which provide a good base upon which to build. The involvement of experienced rideshare agency staff provides a way for making step-by-step, understandable progress toward revolutionary improvement.

First, add occasional riders to existing pools. Occasional pool members needing rides send voice mail requests for pool car drivers.

Then, recruit new IHOV drivers from the ranks of SOV drivers. These new IHOV drivers would provide occasional rides to friends, neighbors and co-workers.

Next, expand the matching system beyond commuting to daytime work-related travel to meetings.

Lead times for ordering rides begin long, but shorten as technology improves and the number of participant vehicles increases.

Add non-working senior citizens to affinity groups for occasional rides.

Eventually, add Saturday and Sunday daytime service.

As IHOV grows and evolves, marketing by rideshare agencies shifts from arranging regular commute-hour pooling matches to selling broader participation in the IHOV system.

As a first stage operational test of IHOV concepts, we would envision expanding carpooling beyond its traditional meaning by creating clusters of affiliated drivers and riders in companies or buildings who share rides during commute hours, coordinated with voice mail and cellular telephones.

One initial implementation step of Bellevue TMA Mobility Innovations has been to gain experience with incorporating cellular telephone service and associated voice mail service as an integral part of carpooling and vanpooling. In October 1991 McCaw Cellular One made a grant of equipment and service through Bellevue TMA to six pool vehicles. As indicated earlier, cellular voice service and integral voice mail service (which are both based on sophisticated computer processing) are the preliminary foundations for a more complex computer-based ridematching system requiring both voice and data communications from drivers and passengers in any location. In the meantime, better mobile communications can make the process of coordination between travelers work better. For example, drivers can let riders know that they are three minutes from being picked up, so they know exactly when to be walking out the door.

Another step in implementing the IHOV public transportation system would be investment in low- to medium-cost capital projects that provide denser (but not overly congested and inaccessible) traveler origins: park-and-ride, drop-off (kiss-and-ride), and transfer centers. These RideMeet places would be locations where travelers would have a greater probability of being picked up quickly by an IHOV driver. Travelers would meet at these locations after arriving by other modes, such as walking, bicycle, SOV or another HOV. They would use their own personal communicator or a calling device at the RideMeet location to communicate with the IHOV dispatching system. The waiting passenger would then be informed of the time that a vehicle would be there to pick them up. This next vehicle could be any type of IHOV transportation: carpool, vanpool, contract taxi or small bus.

Also, the Bellevue Smart Traveler project is testing the effect of providing high-quality, personalized traffic information to pool vehicle drivers through cellular telephone communications.

One certain requirement of a prominent, institutionalized IHOV system is the establishment of new liability insurance coverages. The issue of new forms of public liability exposure as IHOV evolves is common to many areas of IVHS.


IVHS technology in the form of mobile telecommunications with associated computer applications turns SOVs into IHOVs. Electronic information technology will eventually be an integral part of every metropolitan region's high-occupancy-vehicle transportation system. Hundreds of miles of diamond lanes gain added appeal through the transportation-related usage of the invisible but powerful telecommunications infrastructure.

Renowned suburban transportation observer Anthony Downs of the Brookings Institution thinks that the best answer to intolerable suburban traffic congestion is to buy a car with dark tinted glass, air conditioning, a CD player and a microwave, and then just sit back, relax and enjoy. We urge, however, that public transportation leaders not give up the fight for community mobility so easily. By embracing the private automobile as an underused people-carrying resource, and by molding information technology into a new kind of public transportation system, IVHS yields a revolutionary opportunity to add some very positive community value to our personal car-centered lifestyles.

Appendix A: Background on Bellevue

Bellevue TMA is an established partnership of the Seattle regional transit agency called the Municipality of Metropolitan Seattle (Metro), the Bellevue municipal government, and the downtown association of property owners and large employers. The association's staff work continuously on increasing the market share of transit and pooling for commuting into downtown Bellevue, with nationally acclaimed success. The Bellevue central business district is a compact twelve square-block employment center where 24,000 people work in 1,700 businesses. Currently, about 10 percent of the commuters into downtown Bellevue use carpools and vanpools, while 7 percent ride the bus. This 17 percent market share is an outstanding success compared with the under 5 percent national market share for suburban public transportation.

Appendix B: Comparison of an IHOV ridematch system to an airline reservation system

The contemplated IHOV ride request/reservation system and transaction monitoring/accounting system are similar in concept and functionality to computerized airline reservation systems, which constantly manage reservations, passengers, flight schedules, airplanes and individual pieces of baggage.

For example, the American Airlines SABRE computer system has evolved over 25 years into the world's largest privately owned computer network, capable of handling 50 million messages per day. The system runs off five large IBM mainframe computers, with an additional one as a hot backup, ready to be turned on in case one of the other ones breaks down. These computers are located in Tulsa, Okla., in a $337 million building 16 feet below ground, designed to be wind-resistant up to 350 miles per hour and earthquake-proof up to the top end of the Richter scale. To foil terrorists, any authorized person entering the building is identified three different ways: by an identity card with encoded information read electronically, by an optical scanner that reads the unique patterns in the retina of the eye and by weight (which prevents tailgating). The system is hooked into the public telecommunications network by two separate fiber optic cables following two different paths out of the area. Each of the two cables carries half the communications load, so the fact that they both work is always known. If one goes out, computers transfer the entire communications traffic load to the remaining one that works.

Attached full-time to the computers, via telecommunications, are more than 100,000 input/output devices located all over the world, including the TV screens distributed in airports with arrival/departure information, the keyboard and screen terminals at every American Airlines ticket counter and departure gate, plus video terminals in more than 12,000 travel agent offices. Furthermore, any personal computer that is equipped with a modem for attachment to an ordinary telephone line can now be dialed into a part of the SABRE system called EAASY SABRE. A person can look up prices and schedules, make reservations and order tickets to be mailed to a home or office. In fact, the system now has a voice response mode that anybody with an ordinary telephone can dial into for flight schedule information.

The day-by-day changeable setting of the number of seats on each individual airplane available to be sold at discount rates is one impressive capability. As the day of a flight gets closer, the percentage of discounted price seats can be raised, to get the airplane closer to full before takeoff.

Another capability SABRE has is to target individual customers for personal attention. For example, one trade paper described a banker who flew on American Airlines back and forth between New York City and Chicago for 42 straight weeks. When his needs changed, and he stopped those flights, the computer sent him a "personal" letter over an executive's signature asking if there was anything about the airline that displeased him. The banker was so taken by this show of personal attention that he has been a devoted American Airlines passenger ever since.

These systems, which carry information on competitors' flights as well, are more profitable than the airline's flight operations. Travel agencies that use the system are charged a fee for each booking they make via the system. In one recent year, SABRE made a 30 percent profit while ticket sales made 5 percent.

A fully elaborated IHOV computer system for a single metropolitan area would rival the complexity and transaction volume of a worldwide airline reservation system like SABRE.

Appendix C: Catalogue of potential discomfort and danger arising when strangers share a vehicle

1. John Niles is President, Global Telematics. 4005 20th Ave West, Suite 111, Seattle, WA 98199 USA; (206) 781-4475; electronic mail to jniles@alum.mit.edu .

2. Paul Toliver, former Director of Transportation, King County Washington, is retired and still occasionally consulting as of 2019, a year in which he was honored as a new member of the American Public Transportation Association (APTA) Hall of Fame for his lifetime of service.

3. Hawaii Department of Planning and Economic Development, Proceedings - Governor's conference on videotext, transportation and energy conservation. Honolulu, 1984.

4. Other related research on technology-enhanced carpooling is under way [as of 1992] by Professor Louis Pignataro at the New Jersey Institute of Technology, Denise Pieratti at University of Washington, Don Loseff at City of Redmond, Mary Kihl at Iowa State University and John Miller at University of Virginia, among others.

5. Federal Highway Administration, Introduction to Ridesharing: A Manual for New Ridesharing Coordinators (FHWASA88-015, October 1987): 18.

6. Powershift (Bantam Books, 1990).

7. The New Realities (Harper & Row, 1989).

8. 2020 Vision, coauthored by William Davidson (Simon & Schuster, 1991).

9. In numerous public speeches during 1991, including one at the PII conference in Las Vegas, Nev., Oct. 29, 1991.

10. Steve Beroldo, "Casual Carpooling in the San Francisco Bay Area," Transportation Quarterly 44 (January 1990): 133-150; Arlee T. Reno, William A Gellert and Alex Verzosa, "Evaluation of Springfield Instant Carpooling," Transportation Research Record 1212 (1989): 53-62.

11. Urban Mass Transportation Administration, Mobility Management and Market Oriented Local Transportation, DOTT9207 (March 1991).

12. "Software that can dethrone 'computer tyranny,'" Business Week (April 6, 1992): 90.

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