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Sunday, August 6, 2017

Will Persons with Disabilities be Left Out of the AV Revolution?

Automobile manufacturers are teaming with city planners, traffic planners and highway Engineers in the hopes of reducing urban traffic, parking demands, and collision injuries and deaths on the nation's highways. Millions of dollars are being sped to Research and Development to address those concerns.

The theory of AV deployment is that such conveyances will not consume parking space thereby reducing the capital costs of urban buildings. Vehicles will be shared-use and be made available on demand like in traditional taxicabs, Uber and Lyft services except without the cost of a driver.

The vast number of collisions, injury and death on the nation's highways are the result of driver error. The hypothesis is in one takes the humans out of the control system then fatigue, distraction, aggressive behaviors and limited reflex/reaction times will not be the cause of those injuries and death. Most of all the effects of intoxication, responsible for fully half of highway deaths, will be solved. These motives are admirable in and of themselves.

The neglected motive for deploying AV is for people who cannot drive due to age, poor eyesight, other disability or waning ability. For such people taxicabs and other modern variants remain beyond the scope of the business model.

As with the vast majority of business models the plan is to skim off the top the most easily served customers and leave the remaining ones for someone else to handle. The customer using a wheelchair has been relegated to an inferior service model called Complementary Paratransit. "Complementary" refers not to being free but being alongside fixed-route public transit.

Taxicab operators have been slow or complete resistant to accessible vehicles for wheelchair using customers even though since 1990 they have been under regulation to serve persons with disabilities. They have not done so using the logic "we don't do that." The Uber and Lyft operations have likewise kept their model such that they do not serve the entire public. They only serve the segment which they deem comfortable doing and profitable.

Urban-based AV are going to be the next generation of automation to eliminate human employment. Taxis and Ubers already serve the limited public who can enter and exit the vehicle which it is still in the travel lane of the urban street. Serving the remaining public is the challenge of AV developers.

Highway driving AV will typically be owner-occupied. That is people will purchase an AV and commute their 30-50 mile radius and make their occasional long-distance inter-city trips. For them the AV is a convenience rather than a necessity. Yes, the AV should significantly reduce the collision rate of such long trips.

The urban circulation of people and vehicles will require 1,000s of hours of "learning" for the AV to be effective. Fortunately such learning is transferable from vehicle to vehicle unlike the learning process of a human driver.

Detroit's Automated People Mover
For persons with disabilities who have been neglected for decades, the AV promises to be the difference between night and day. Unlike the general public, to obtain individualized trips within a local region presently persons with disabilities must apply for and be ruled eligible for Complementary Paratransit services provided by a local transit agency. They must make a reservation one or more days in advance. Such reservations must include the Origin, Destination, desired Pickup time and anticipated return time. Then a shared ride vehicle arrives within a 15 to 20 minute (earlier/later) time frame. Unlike shared use vehicles where a multiple people use the same vehicle one after the other, this ride will be shared ride with other passengers at the same time. Such scheduling seeks to optimize the ride carrying capacity of the vehicle. The passengers get no choice in how many people share their ride, where they are going or for what reason.

AV which can accommodate a wheelchair or two plus a few ambulatory passengers and that can find the curb would be the solution many persons with disabilities have sought for many decades.

The development of an accessible AV system would have some typical characteristics.

  • It would be a minivan sized vehicle that can seat 2 wheelchairs and 3 or 4 ambulatory passengers in the primary passengers group.
  • It would have curb access with ramps on both sides of the vehicle to accommodate service on one-way streets.
  • It would not rely exclusively on voice commands to initiate and conclude a trip.
  • It would be able to find the curb and stop close enough to pickup and discharge the passengers.
  • It would be able to recognize curbside barriers such as utility poles, trees, parking meters, trash bins, benches, fire hydrants, mailboxes, etc. and not stop there.
  • It would be able to attach a form of mobility aid securement to the aid if the passenger or his designated assistant could not do it instead.
  • Such AV stock would be plentiful enough to afford persons with disabilities with the same level of service, timeliness and reliability.

In order for the promise of AV to be realized the users need to be inside the urban service area. This means they will dwell there or will arrive there by other means than a private automobile (AV or otherwise). This opens the market for vanpools, biking, trains, walking and commuter buses. Some of those modes may also be equipped with AI to operate them.

The scenario of an sedan-sized AV being used to first make a long commute then go into service as an urban circulator is a non-starter. Needing to store a car in the city during the day also defeats the purposes of AV in the first place.

Pittsburgh's Failed SKYBUS Project (Circa 1964)
Some cities already have driverless automated transit modes and have for many years. Detroit's People Mover is such a system and is already 30 years old. It operates in a 2.9 mile loop in the central city. Miami operates the Metro Mover on 4.4 miles of elevated track. Both systems are electric and are fully automated. Their usage helps define where future development will occur.  In 1964, Pittsburgh, PA started the controversial Skybus system. It was to be a fully automated rubber tire vehicle which traveled on a concrete fixed guideway.  Even with a demonstration track in the South Hills the project lost political favor and was cancelled.

AV for city streets is a goal to bring such people moving capabilities to private seating running on existing public rights-of-way. While that lofty goal is admirable, cities will ultimately need to invest heavily in new architecture and amenities to make AV a viable form of inner city transportation for everyone.

Thursday, August 3, 2017

Integrating BRT and Bike Lanes into an Inclusive Urban Design

Following the lead of Curitiba, Brazil in dedicated transit priorities many US Cities have become enamored of the idea for allocating existing right-of-way space to dedicated bus and bike lanes.

The cities are responding to the lobbying pressures of bike-riding constituents and their representative organizations to improve biking safety by creating curbside protected lanes. These physically separated bikeways may very well decrease the frequency and severity of bike/motor vehicle collisions but they also limit access to the sidewalks by taxis, Ubers and Lyfts, and the transit authorities mandatory Complementary Paratransit services for persons with disabilities under the Americans with Disabilities Act.

In locations where the business community is sufficiently vocal, the non-protected bike lanes are being striped between the curbside larking lane and the rightmost motor vehicle travel lane. In such locations, bike riders continue to be in jeopardy of suddenly opened parked car doors and the need for fixed route transit buses to cross to reach the bus stops at the curb.

The protected bike lanes create shared use limitations for persons with disabilities who arrive and depart an address on the block via Complementary Paratransit services. Whereas the general public has no specific right to be picked up or dropped off nearest their intended destinations, persons with disabilities DO have such a Civil Right as enumerated in CRF Part 49, Sections 27 and 28, and guaranteed by the Americans with Disabilities Act since 1990.

The rise of Bus Rapid Transit (BRT) service designs are beginning to create similar access limitations for persons with disabilities too. Where the BRT buses are on wholly separated guideways, they may present limitations for bus access for persons with disabilities, but they do not limit to the curb from adjacent travel lanes.

Where the existing right-of-way is being reconfigured to accommodate dedicated bus travel, long stretches of urban street may be unavailable for Complementary Paratransit vehicles to services passengers with disabilities who need to visit the specific block where the BRT lane restricts access.

In a worst-case scenario, as in the Oakland section of Pittsburgh, PA, there is already a counter flow dedicated bus lane on the left side of the street and a proposed protected bike lane for the right side. This configuration runs for several blocks through the University of Pittsburgh and would create an "access desert" in one of the most highly visited sections of the city.

Several alternatives are under consideration for this BRT/Bike Lane development. The clear take away from the initial studies is that access by Complementary Paratransit vehicles is a complete afterthought.

While the final design criteria has not officially been adopted, many advocates of persons with disabilities have voiced their concerns and want to shape the implementation in advance of construction. None of the alignments or street profiles address how a Complementary Paratransit vehicle will access the sidewalks.


Minnesota DOT hired a consultant in 2013 to identify bike lane development criteria which included upfront and continual participation of advocates for biking as both Recreation and as Transportation. This planning process is analogous to the one that should be employed in the early development of BRT and other public projects which restrict or eliminate access to the curb by public and private vehicles serving persons with disabilities. While transit use promotes walking as one of the trip legs and a 1/4 to 1/2 mile distance may not be onerous for the general public, persons with disabilities may not be able to traverse even one block from vehicle to door.

The accommodation to persons with disabilities use wheelchairs is the smaller portion of the overall mobility limited population who need to be heard and served. Frail elderly, blind, and other semi-ambulatory people are part of what "accessibility" is designed for.

Some suggestions are to create "Paratransit Stops" at the lead or trailing end of the block to allow Complementary Paratransit vehicles to cross the bike lane demarcations to service scheduled passengers. A similar design parameter would allow the Complementary Paratransit vehicles to travel a single block of the BRT or counter flow bus lane and stop at a curb inset to pickup and drop off their passengers. Specific geometries need to be evaluated for each type of accommodation. Because all of these solutions will involve infrastructure modification as well as policy decisions, this is where consumer input would be most valuable.