Tilting train
A tilting train is a train that has a mechanism enabling increased speed on regular
The first passive
Starting in the late 1960s, British Rail began experiments with its Advanced Passenger Train (APT) which pioneered the active-tilt concept. This used hydraulic rams on the bottoms of the carriages to tilt them, rotating them around their centre point rather than swinging outward. This had the advantage of keeping the carriage centred over the bogies, which reduced load on the rails, and could be turned off when navigating switches. Due to lengthy delays, the APT did not begin test runs until 1981 and entered commercial service only briefly in 1985. By this time, the Canadian LRC design had become the first active tilting train to enter full commercial service, starting with Via Rail in 1981.
Fiat developed their Pendolino design into the most successful type of tilting train, with over 500 trains active in Europe. The concept of active tilt as a whole has been independently developed by many companies. Active tilting systems are widely used today.
Design
Aeroplanes and bicycles tilt inwards when cornering, but automobiles and trains cannot do this on their own. Vehicles with high centres of gravity rounding sharp curves at high speeds may topple over. To make their turns easier, the outer edge of a roadway of a high-speed highway or outer rail of a railway may be canted (raised) upward around the curve. The combination of tilt and centrifugal force combines to produce an effective acceleration that is down through the floor, reducing or eliminating any sideways component.
The particular angle of tilt ("superelevation") is determined by the intended vehicle speed — higher speeds require more banking. But with a growing desire in the 1960s and 1970s to build high-speed rail networks, a problem arose: the amount of tilt appropriate for high-speed trains would be over-tilted for lower-speed local passenger and freight trains sharing the lines. Japan's early bullet train efforts of the 1960s avoided this problem by laying all-new lines as part of a re-gauging effort, and France's TGV followed the same pattern. Other operators did not have this luxury and were generally limited to much lower speeds.
Spain's national railway
Tilting trains are meant to help reduce the effects of
More limited and slower tilt could be achieved using active, or 'forced', tilting mechanisms. In trains adopting these mechanisms tilt is initiated by computers, which 'force' train bodies to tilt at specific angles based on track information. This information could be stored on board or detected using a sensor at the front of the train or using Automatic train stop beacons. The slight delay in reacting to this information leads to a short period of sideways force while the cars react. It was found that when the cars tilt just at the beginning of the curves instead of while they are making the turns, there was no motion sickness.[4] Researchers have found that if the tilting motion is reduced to compensate for 80% or less of lateral apparent force, then passengers feel more secure. Also, motion sickness on tilting trains can be essentially eliminated by adjusting the timing of when the cars tilt as they enter and leave the curves.
A similar technology widely adopted across Asia and Oceania, known as controlled passive tilt, achieves a similar effect by using on-board computers to limit tilt, initiated using inertia (as in traditional passive tilt). Automatic train stop beacons are used to inform computers of the precise location of these trains and limit natural tilt to angles specified by track data.
High-speed trains
A high-speed tilting train is a tilting train that operates at high speed, typically defined as by the European Union to include 200 km/h (124 mph) for upgraded track and 250 km/h (155 mph) or faster for new track.[5]
Tilting trains operating at 200 km/h (124 mph) or more on upgraded track include the Acela in the US, the X 2000 in Sweden, the Pendolinos and Super Voyagers in the United Kingdom, and the ICE TD in Germany (the latter two being diesel powered).
Some older high-speed lines were built for lower line speeds (≤ 230 km/h (143 mph)); newer tilting trainsets can maintain higher speeds on them. For example, the Japanese
Many high-speed trainsets are designed to operate on purpose-built high-speed lines and then continue their journeys on legacy lines, upgraded or not. Where the legacy lines justify it, a tilting train may operate at higher speeds on the latter, even if below the normal 200 km/h (124 mph) threshold, whilst operating at 250 km/h (155 mph) or faster, usually with tilt disabled, on the high speed lines.
History
Pendulum car
The first experimental tilting train concept was the pendulum-suspension "chair" cars designed by the Pacific Railway Equipment Company. The first prototype, with an articulated bogie system, was built in 1937 and tested on the Atchison, Topeka and Santa Fe Railway that year. The company built another three pre-production models in 1939, using more conventional fore-and-aft bogies, and these saw some use with the San Diegan, among others. Mounted on high springs, the car tilted inwards on curves to counterbalance the cant deficiency with the induced centrifugal force. The opening of World War II prevented any immediate orders, and the concept was not revived in the post-war era.
SNCF experiment
In 1956, SNCF experimented with a self-propelled pendulum car, which also relied on centrifugal force. This experiment demonstrated the need for an active suspension system to tilt the coach bodies.
Talgo Pendular
The Spanish Talgo company had introduced the first widely successful shared-bogie system, which allowed cars to be connected end-to-end using a single bogie instead of each car having its own bogies at either end. This design saves weight and can reduce rail wear.
In the early 1950s, Renfe experimented with passenger cars that combined the Talgo bogie with a new passive tilting system. This system used a large A-frame connected to the centre of the bogie that was as high as the cars. At the top of the A was a bearing system that the cars attached to, and a spring and damping system to smooth its motion. Because the cars were connected at this high point, they could swing to either side around the bearing axis, and this caused them to naturally pendulum outward on curves.
The first test of a Talgo in the United States was the
The first successful European tilting train design was the Talgo in Spain, developed in the 1970s as a lightweight, fast train using passive tilt. The Spanish National Railway, Renfe, adopted the system widely, but was restricted to the Iberian peninsula initially.
The first full commercial application of passive tilting trains appeared in early 1980s with the Talgo Pendular. Talgo is currently in its 21st generation of production. Talgo trains are in service in various parts of Europe, and built under licence in Latin America and Asia. In North America, Amtrak uses Talgo trains in its Cascades service in the Northwest.
The first Talgo tilting series were the "pendular" ones from 400 series onwards.
UAC TurboTrain
The first tilting train to enter into regular service in North America was the
Pendolino
In Italy, the studies for a tilting train started in the mid 1960s and the concept was patented in 1967 by two engineers of Fiat railway materials, Franco di Maio and Luigi Santanera. A number of prototypes were built and tested, including an automotrice (self-propelled) derived from
This design led to the construction of an entire EMU in 1975, the
New interest by the Italian government in the project in the mid 1980s, and the introduction of new technologies, led to the revision of the project with the ETR 401 with electronic systems, that led to the introduction of the slightly more advanced
In 1989, the old technologies and concepts of some parts of the ETR 450, and the introduction of new technologies in traction, led to the development of the next generation. The result was the
ETR 460 keeps axle load to an extremely low level (14.5 ton/axle), to allow the train to negotiate curves up to 35% faster than conventional Intercity trains (locomotive plus coaches). The body, which exploits large aluminium extrusion technology, has substantial modularity and allows for extremely low axle weight, whilst fully respecting the highest safety standards, and allows the best exploitation of the space with different loading gauges.
ETR 460 was built in only 10 units. Improved versions include
The development of the Pendolino technology continued in the Italian factories of Alstom and the next generation, the
Italian Pendolinos and their derivatives still represent the most popular solution for active tilting in passenger trains. The technology still in use today is almost the same developed by
The British version of the Pendolino, the
Japanese designs
Tilting trains have long been a mainstay of express services on Japan's conventional-speed,
The first commercial tilting EMU in Asia entered service in 1973 as the 381 series EMUs on Shinano limited express services operating on the hilly Chūō Main Line between Nagoya and Nagano, and is still in operation on the "Yakumo" service on the Hakubi Line despite its shortcomings in ride quality and increased track wear due to its tilt mechanism that allowed up to 5° of tilt.[7]
During the final years of the
This generation of designs has seen some popularity overseas - the 8000 series serves as the basis of the Electric Tilt Train built for Queensland Rail's Cape Gauge network. The 885 series, built as part of the Hitachi A-train family, serves as the basis of the Taiwanese TEMU1000 series tilting EMU for Taroko Express services, and some non-tilting variants including the British Rail Class 395 and British Rail Class 801.
Later developments in pneumatic active suspension - based on the
German designs
Deutsche Bundesbahn started tests with tilting trains in Germany with its class 634 in 1967 when some class 624 DMUs were equipped with passive tilting systems. As the passengers experienced motion sickness, the tilting technology was disabled and later removed. The tests continued with the prototypes of the following class 614 units, but due to the again unsatisfying results the serial types were delivered without tilting system.
Another early train with tilting technology was
The next attempt was made with DMUs and the proven Italian hydraulic active tilting system. Between 1988 and 1990 DB commissioned 20
In 1999 DB was able to use tilting technology for its
Much of the technical layout is derived from the ICE 3. Austria's ÖBB has purchased three units in 2007, operating them jointly with DB for services from Germany to Austria. Even though DB assigned the name ICE-T to class 411/415, the T originally did not stand for tilting but for Triebwagen (self-propelled car), as DB's marketing department at first deemed the top speed too low for assignment of the InterCityExpress brand and therefore planned to refer to this class as IC-T (InterCity-Triebwagen).
Rather luckless was class 411/415's adaptation for diesel services. In 2001 a total of 20 units were commissioned for use on the Dresden–Munich line, but these class 605 (ICE-TD) units experienced trouble from the start. After breaking an axle in 2002, all remaining 19 units (one fell off a working platform) were taken out of service. Even though one year later the trains were admitted to service again, DB judged their operation to be overly expensive. In 2006 those trains were used for amplifier trains and from 2008 to 2017, they ran on the Hamburg–Copenhagen route. Since 2018 and 2021, two units are in operation as the advanced TrainLab test train.
Light, Rapid, Comfortable
In 1966, a consortium of Canadian industrial firms began considering a conventionally-powered competitor to the TurboTrain, eventually emerging as the LRC (Light, Rapid, Comfortable) in the early 1970s. This design also used an active-tilt system, but one of very different form than the APT. The carriages rode on two C-shaped channels mounted across the top of the bogies. Tilt was accomplished by rams that pushed the bottom of the carriage side to side along these channels.
Amtrak experimented with the LRC in 1980, but retired it seven years later. In Canada, it entered service in 1981, beating the APT into service and becoming the first operational active-tilt system. The LRC carriages remain in use today, although the tilt mechanisms are being removed to reduce weight and maintenance costs.[11]
Bombardier has since used updated versions of the LRC carriages for Amtrak's Acela, the third generation of tilting ICE, the new generation of fast British trains (Super Voyager) and the experimental JetTrain.
Advanced Passenger Train
The Advanced Passenger Train (APT) was initially an experimental project by British Rail, with the train entering service in 1984. Although eventually abandoned, the train was the pioneer of active tilt to negotiate tight curves at higher speeds than previous passive tilting trains. For various reasons, political and technical, after running in service for a year, the train was withdrawn.
In the 1970s and 1980s, British Rail wanted an advanced fast train to negotiate the UK's twisting and winding
Engineers at the research division, opened in 1964, had done fundamental work on vehicle dynamics, with the APT to a degree an extension of this. The existing Chief Mechanical and Electrical Engineers department was overlooked by the new project, creating resentment with its engineers. The work included experimentation with aluminium bodies, turbines, suspension and bogies, and active tilt.
The APT-E (E for experimental) was powered by gas turbines; the APT-P (P for prototype) was electric. With no tilting, the train was developed to break the British rail speed record. Tilting trains using passive tilt were not new, but it was uncommon and not widely implemented. The engineers decided that active tilt was the key to negotiating curves at much higher speeds.
The train had hydro-dynamic brakes and lightweight articulated bodies, with two power cars in the centre of the train. When the prototypes were built, worked and proven, the engineering development team was disbanded and the trains handed over to British Rail's in-house engineering department to build. The developing engineers moved on to different fields while British Rail engineered the train into a production model. The BR engineers, who had little to no involvement in the development of the train, changed some of the prime and proven engineering aspects. For example, they changed the active tilt mechanism to pneumatic, rather than the well-developed and proven hydraulics.
The trains were introduced in 1981, but almost immediately taken out of service. During initial tests, some passengers complained of being nauseous due to the tilting motion. Subsequently, it was learned that this could be prevented by reducing the tilt slightly, so that there was still some sensation of cornering. The APT-P trains were quietly reintroduced to service in mid-1984 and ran regularly for a year, the teething problems having been corrected. However, under an in-house engineering management who felt slighted and by-passed in a project they had not developed, there was no political or managerial will to continue the project by building the projected APT-S production vehicles in numbers. Despite being an eventual success, the project was scrapped by British Rail in 1985, more for political reasons than technical.
Much of the technology developed for the power cars was subsequently used in the InterCity 225 Class 91 locomotives and Mark 4 carriages which were designed to be retrofitted with tilting equipment, which run on the East Coast Main Line route from London to Leeds and Edinburgh.
X 2000
In 1990 Swedish railways introduced a high speed service called X 2000. The train uses an active tilting system, enabling higher speeds of (200 km/h or 124 mph) on standard track. The train was also used in Norway and Denmark but later the train was removed from service in Norway. The X 2000 has been tested in USA, Canada, Australia and China. X2000 was a collaborative project by Kalmar Verkstad, Swedish railways and ASEA.
TGV Pendulaire
In 1998 SNCF bowed to political pressure (the tilt-train was a credible threat to the TGV dedicated high-speed line network) and put in service an experimental TGV pendulaire. Only the passenger trailers were tilting while the two heavy power cars kept non-tilting bogies. Following the test program, it was converted back to a TGV-PSE train.
InterCity Neigezug
Switzerland got its first tilting train ever in its territory (discounting the
Bombardier Super Voyager
Forty-four diesel-electric powered
Tilting Train Express
The Tilting Train Express(TTX) or Hanvit 200 is a prototype 6-car experimental tilting train developed and built in South Korea. Revealed in 2007, it had multiple test runs, including one which recorded a maximum speed of 223km/h. However, no production units were made as it was determined that it would be less costly to straighten existing trackage and banking the rails. It has done further test runs in 2014, however, to test the LTE-R system.
Technology
Many of the problems with motion sickness are related to the fact that traditional servo systems respond inappropriately to the changes in trajectory forces, and even small errors, whilst not being consciously perceivable, cause nausea due to their unfamiliar nature. The original Fiat ETR 401 used individual gyroscopes in each carriage so there was a lag, even though nausea had not been a major problem with this train. The APT was supposed to overcome this problem by using gyroscopes at the ends of the train and a leader/follower control system which defined a "tilting curve" for the whole train. It would appear that the technology of the era was unable to properly implement this technique.
Modern tilting trains profit from state-of-the-art signal processing which senses the line ahead and is able to predict optimal control signals for the individual carriages. Complaints about nausea have largely become a thing of the past.
Some tilting trains run on
With tilting EMU's, consideration is required on keeping the pantographs within the railway gauge. When mounted on top of a tilting car, the pantograph usually sways in the opposite direction in order to counter for the degree of tilting. This is done mechanically on for instance the British Class 390 Alstom Pendolino. On the German class 411 and 415, the pantographs are however mounted on a separate non-tilting frame within the cars.
Tilting trains around the world
Trains with tilting by inertial forces (passive tilt):
- Talgo XXI (Spain)
- UAC TurboTrain (United States, Canada)
- JNR 381 series (Japan), introduced in 1973 by the former Japan National Railways. Currently used by JR West for Yakumolimited express services.
Trains with tilting initiated by inertial forces but regulated by computer:
- . The upgraded N2000 Series was introduced in 1995.
- Super Hokutolimited express service.
- JR Shikoku 8000 series (Japan, 1992). Used on limited express services on the Yosan Line, namely Ishizuchi and Shiokaze.
- JR East E351 series (Japan, 1993), formerly used on the Super Azusa limited express.
- HOT7000 series (Japan, 1994), used on the Super Hakutolimited express.
- Wide View Shinanolimited express.
- Huis ten Bosch and Kamomelimited expresses.
- JR Hokkaido Super Tokachilimited expresses.
- JR West 283 series (Japan, 1996), used on the Kuroshio limited express.
- JR Kyushu 885 series (Japan, 1999), used on the Kamome and Sonic limited expresses.
- JR West KiHa 187 series (Japan, 2001), used on the Super Inaba, Super Matsukaze, and Super Oki limited expresses.
- JR Shikoku 2700 series (Japan, 2019), used on the Ashizuri, Nanpū, Shimanto and Uzushio limited expresses.
- TRA TEMU1000 series (Taiwan, 2007) use for Taroko Express, based on JR Kyūshū 885 Series.
- JR Shikoku 8000 series.
Trains with active tilt controlled with sensory information given by accelerometers:
- LRC designed by MLW before being bought by Bombardier (Canada)
Trains with tilting controlled by a computer:
- Washington DC
- Advanced Passenger Train (United Kingdom), a British Rail project for high-speed inter-city tilting trains that saw limited service in the 1980s, from London Euston to Glasgow.
- British Rail Class 390 "Pendolino" (United Kingdom), a high-speed train run by Avanti West Coast from London Euston to Liverpool/ Manchester / Glasgow / Birmingham and Wolverhampton.
- Alfa Pendular (Portugal)
- ElettroTreno (Italy)
- ICE
- ICN (Switzerland), a new generation of tilting trains operated by Swiss Rail, a Bombardier-built high-speed tilting train operating between Zurich and Geneva.
- JetTrain (North America), Bombardier's experimental non-electric high-speed train
- NSB Class 73 (Norway)
- NSB Class 93(Norway) Used on unelectrified regional services in northern Norway
- Split, and Zagreb–Rijeka
- Pendolino (Italy, Finland, United Kingdom, and Czech Republic), built by Alstom (formerly Fiat); see also the British Rail Class 390 and Finnish VR Class Sm3.
- Super Voyager, a Bombardier-built high-speed tilting train operating between London and Holyhead / Wrexham / Chester and Birmingham to Edinburgh or Glasgow.
- X2 (Sweden), with tilting mechanism of ABB. It was also used in China under the name Xīnshísù.
- JR Hokkaido Sapporo.
- JR Hokkaido Super Sōyalimited express service.
- Meitetsu 1600 series (Japan, 1999), branded Panorama Super. Mainly used for Meitetsu Nishio Line limited express trains.
- Chūbu Centrair International Airport.
- Odakyu 50000 series VSE (Japan, 2005), used for Romancecar limited express services.
- TTX (South Korea, 2007), later named Hanvit 200, experimental prototype for potential tilting trains in South Korea, with a max speed of 200km/h and a service speed of 180km/h. Production units not made.
- Sanyō Shinkansenservices.
- E5 Series Shinkansen (Japan, 2011), introduced by JR East, used on Tōhoku Shinkansen and Hokkaido Shinkansenservices. Pooled with nearly identical H5 series units.
- E6 Series Shinkansen (Japan, 2013), introduced by JR East, used on Tōhoku Shinkansen and Akita Shinkansen services.
- TRA TEMU2000 series (Taiwan, 2013) use for Puyuma Express.
- H5 Series Shinkansen (Japan, 2014), introduced by JR Hokkaido, used on Tōhoku Shinkansen and Hokkaido Shinkansenservices. Pooled with nearly identical E5 series units.
- Ishizuchilimited expresses.
- E353 series (Japan, 2015), introduced by JR East, used on Azusa and Kaiji limited expresses.
- 2600 series (Japan, 2017), introduced by JR Shikoku, used on Uzushio and Shimanto limited expresses.
See also
References
- OCLC 170056962.
- ^ "High-speed tilting train on track". BBC News. 12 December 2005.
- ^ Valenti, Michael (1998). "Tilting trains shorten transit time". Mechanical Engineering. Archived from the original on 4 June 2011.
- ^ "New study shows how to eliminate motion sickness on tilting trains". Icahn School of Medicine at Mount Sinai. 4 August 2011.
- ^ "General definitions of highspeed". International Union of Railways. Retrieved 13 May 2009.
- ^ 「小田急座談 (Part1) 車両編」、『鉄道ピクトリアル アーカイブスセレクション』第1号、電気車研究会、2002年9月、 6-16頁。
- ^ a b Mochizuki, Asahi (March 2010). "Electric Trains and Japanese Technology" (PDF). Japan Railway and Transport Review. Archived (PDF) from the original on 10 January 2017. Retrieved 31 May 2022.
- ^ "Das Geheimnis der Achse". Süddeutsche Zeitung (in German). 22 November 2008. Archived from the original on 20 February 2009.
- ^ "Weisung für Triebfahrzeugführer der ICE-T vom 23. Oktober 2008" (PDF).[permanent dead link]
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- ^ "An All-Canadian Rail Innovation from Roof to Wheels" (PDF). VIA Rail. Spring 2009.
- ^ CrossCountry removes tilt from its 221 Voyagers Rail issue 595 2 July 2008 page 8
- ^ "World's fastest on narrow tracks - National - www.smh.com.au". www.smh.com.au. 17 November 2004. Retrieved 27 June 2017.