Editing Personal rapid transit (section)

==Overview==
Most [[mass transit]] systems move people in groups over scheduled routes. This has inherent inefficiencies.<ref name="ITNS November 2014">{{cite web|url=http://www.advancedtransit.org/wp-content/uploads/2011/08/ITNS-11-2014.pdf|title=An Intelligent Transportation Network System: Rationale, Attributes, Status, Economics, Benefits, and Courses of Study for Engineers and Planners|author=J. Edward Anderson|date=November 2014}}</ref> For passengers, time is wasted by waiting for the next vehicle to arrive, indirect routes to their destination, stopping for passengers with other destinations, and often confusing or inconsistent schedules. Slowing and accelerating large weights can undermine public transport's benefit to the environment while slowing other traffic.<ref name="ITNS November 2014" />

Personal rapid transit systems attempt to eliminate these wastes by moving small groups nonstop in automated vehicles on fixed tracks. Passengers can ideally board a pod immediately upon arriving at a station, and can – with a sufficiently extensive network of tracks – take relatively direct routes to their destination without stops.<ref name="ITNS November 2014" /><ref>{{cite journal |last1=Ding |first1=Yida |last2=Wang |first2=Kai |last3=Zhang |first3=Lei |last4=Qu |first4=Xiaobo |title=Exploring the benefits of personal rapid transit in metropolitan area |journal=Communications in Transportation Research |date=2024 |volume=4 |pages=100117 |doi=10.1016/j.commtr.2023.100117 |doi-access=free}}</ref>

The low weight of PRT's small vehicles allows smaller guideways and support structures than mass transit systems like light rail.<ref name="ITNS November 2014" /> The smaller structures translate into lower construction costs, smaller [[Track transition curve|easements]], and less visually obtrusive infrastructure.<ref name="ITNS November 2014" />

As it stands, a citywide deployment with many lines and closely spaced stations, as envisioned by proponents, has yet to be constructed. Past projects have failed because of financing, cost overruns, regulatory conflicts, political issues, misapplied technology, and flaws in design, engineering or review.<ref name="ITNS November 2014" />

However, the theory remains active. For example, from 2002 to 2005, the EDICT project, sponsored by the [[European Union]], conducted a study on the feasibility of PRT in four European cities. The study involved 12 research organizations, and concluded that PRT:<ref name="EDICT">{{cite web |url=http://ec.europa.eu/research/environment/newsanddoc/article_2650_en.htm |title=Moving ahead with PRT |archiveurl=https://web.archive.org/web/20060921115952/http://ec.europa.eu/research/environment/newsanddoc/article_2650_en.htm |archivedate=2006-09-21 |website=ec.europa.eu}}</ref>
* would provide future cities "a highly accessible, user-responsive, environmentally friendly transport system which offers a sustainable and economic solution."
* could "cover its operating costs, and provide a return which could pay for most, if not all, of its capital costs."
* would provide "a level of service which is superior to that available from conventional public transport."
* would be "well received by the public, both public transport and car users."
The report also concluded that, despite these advantages, public authorities will not commit to building PRT because of the risks associated with being the first public implementation.<ref name="EDICT"/><ref name="EDICTFinalReport">[http://archive.cardiff.gov.uk/traffic/internet/jondutton/edict/current/CONTENT/Del10%20-%20Final%20Report.pdf EDICT Final Report (PDF)"] {{Webarchive|url=https://web.archive.org/web/20150526165330/http://archive.cardiff.gov.uk/traffic/internet/jondutton/edict/current/CONTENT/Del10%20-%20Final%20Report.pdf |date=2015-05-26 }} from cardiff.gov.uk</ref>

{| class="wikitable"
|+Comparison of personal rapid transit with existing transport systems
!style="text-align:left; vertical-align:top; padding:4px;"|Similar to cars / [[automobile]]s
||
* Vehicles are small—typically two to six passengers
* Vehicles are individually hired, like taxis, and shared only with the passengers of one's choosing
* Vehicles travel along a network of guideways, much like a network of streets.  Travel is point-to-point, with no intermediate stops or transfers
* Potential for on-demand, around-the-clock availability
* Stops are designed to be off the main guideway, allowing through traffic to bypass stations unimpeded
|-
!  style="text-align:left; vertical-align:top; padding:4px;"|Similar to [[tram]]s, [[bus]]es, and [[monorail]]s
||
* A public amenity (although not necessarily publicly owned), shared by multiple users
* Reduced local pollution (electric powered)
* Passengers embark and disembark at discrete stations, analogous to [[bus stop]]s or [[taxi stand]]s
|-
!  style="text-align:left; vertical-align:top; padding:4px;"|Similar to automated [[people mover]]s
||
* Fully automated, including vehicle control, routing, and collection of fares
* Usually above the street—typically elevated—reducing land usage and congestion
|-
! style="text-align:left; vertical-align:top; padding:4px;"|Distinct features
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* Vehicle movements may be coordinated, unlike the autonomous human control of cars and bikes
* Small vehicle size allows infrastructure to be smaller than other transit modes
* Automated vehicles can travel close together. Possibilities include dynamically combined "trains" of vehicles, separated by a few inches, to reduce [[drag (physics)|drag]] and increase speed, energy efficiency and passenger density
|}

The PRT acronym was introduced formally in 1978 by [[J. Edward Anderson]].<ref>J. Edward Anderson, [http://faculty.washington.edu/~jbs/itrans/PRT/Background.html "What is Personal Rapid Transit?"] {{Webarchive|url=https://web.archive.org/web/20060919102551/http://faculty.washington.edu/%7Ejbs/itrans/PRT/Background.html |date=2006-09-19 }}, University of Washington, 1978</ref> The [[Advanced Transit Association]] (ATRA), a group which advocates the use of technological solutions to transit problems, compiled a definition in 1988 that can be seen here.<ref>{{cite web |url=http://faculty.washington.edu/jbs/itrans/PRT/Background.html |title=PRT Background |publisher=Faculty.washington.edu |access-date=2012-10-17 |archive-url=https://web.archive.org/web/20120728094847/http://faculty.washington.edu/jbs/itrans/PRT/Background.html |archive-date=2012-07-28 |url-status=dead }}</ref>