Hyperloop
The outline of the original Hyperloop concept was made public by the release of a preliminary design document in August 2013, which included a notional route running from the Los Angeles region to the San Francisco Bay Area, paralleling the Interstate 5 corridor for most of its length. Preliminary analysis indicated that such a route might obtain an expected journey time of 35 minutes, meaning that passengers would traverse the 350-mile (560 km) route at an average speed of around 600 mph (970 km/h), with a top speed of 760 mph (1,200 km/h). Preliminary cost estimates for the LA–SF notional route were included in the white paper—US$6 billion for a passenger-only version, and US$7.5 billion for a somewhat larger-diameter version transporting passengers and vehicles[2] —although transportation analysts doubted that the system could be constructed on that budget.[4][5][6]
Hyperloop technology has been explicitly open-sourced by Musk and SpaceX, and others have been encouraged to take the ideas and further develop them. To that end, several companies have been formed, and dozens of interdisciplinary student-led teams are working to advance the technology.[citation needed]
Designs for test tracks and capsules are currently being developed, with construction of a full-scale prototype 5-mile (8 km) track scheduled to start in 2016.[7] In addition, a subscale pod design competition on a very short, 1 mile (1.6 km), test track was built in Nevada – the first tests of the scale model occurred in May 2016.[8]
History
The general idea of trains or other transportation traveling through evacuated tubes dates back more than a century although the atmospheric railway was never a commercial success. Elon Musk's Hyperloop may make the idea economically viable[citation needed].Musk first mentioned that he was thinking about a concept for a "fifth mode of transport", calling it the Hyperloop, in July 2012 at a PandoDaily event in Santa Monica, California. This hypothetical high-speed mode of transportation would have the following characteristics: immunity to weather, collision free, twice the speed of a plane, low power consumption, and energy storage for 24-hour operations.[9] The name Hyperloop was chosen because it would go in a loop. Musk envisions the more advanced versions will be able to go at hypersonic speed.[10]
In May 2013, Musk likened the Hyperloop to a "cross between a Concorde and a railgun and an air hockey table,",[11] he also believes it could work either below or above ground.[12]
From late 2012 until August 2013, a group of engineers from both Tesla and SpaceX worked on the conceptual modelling of Hyperloop.[13] An early system design was published in to the Tesla and SpaceX blogs.[2][14] Musk has also invited feedback to "see if the people can find ways to improve it". The Hyperloop will be an open source design.[15] The following day he announced a plan to demonstrate the project.[13][dated info]
In June 2015, SpaceX announced that it would build a 1-mile-long (1.6 km) test track to be located next to SpaceX's Hawthorne facility. The track would be used to test pod designs supplied by third parties in the competition.[16][17] Construction on a 5-mile (8 km) Hyperloop test track is to start on a Hyperloop Transportation Technologies-owned site in Quay Valley in 2016.[18][19]
By November 2015, with several commercial companies and dozens of student teams pursuing the development of Hyperloop technologies, the Wall Street Journal asserted that "The Hyperloop Movement, as some of its unaffiliated members refer to themselves, is officially bigger than the man who started it."[20]
Theory and operation
Artist's impression of a Hyperloop capsule: Air compressor on the front, passenger compartment in the middle, battery compartment at the back, and air caster skis at the bottom
Initial design concept
The Hyperloop concept operates by sending specially designed "capsules" or "pods" through a continuous steel tube maintained at a partial vacuum. Each capsule floats on a 0.5-to-1.3-millimetre (0.02 to 0.05 in) layer of air provided under pressure to air-caster "skis", similar to how pucks are suspended in an air hockey table, thus avoiding the use of maglev while still allowing for speeds that wheels cannot sustain. Linear induction motors located along the tube would accelerate and decelerate the capsule to the appropriate speed for each section of the tube route. With rolling resistance eliminated and air resistance greatly reduced, the capsules can glide for the bulk of the journey. In the Hyperloop concept, an electrically driven inlet fan and air compressor would be placed at the nose of the capsule to "actively transfer high pressure air from the front to the rear of the vessel," resolving the problem of air pressure building in front of the vehicle, slowing it down.[2] A fraction of the air is shunted to the skis for additional pressure, augmenting that gain passively from lift due to their shape.In the alpha-level concept, passenger-only pods are to be 2.23 metres (7 ft 4 in) in diameter[2] and projected to reach a top speed of 760 mph (1,220 km/h) to maintain aerodynamic efficiency;[citation needed] the design proposes passengers experience a maximum inertial acceleration of 0.5 g, about 2 or 3 times that of a commercial airliner on takeoff and landing. At those speeds there would not be a sonic boom.[22]
Notional routes
A number of routes have been proposed for Hyperloop systems that meet the approximate distance conditions for which a Hyperloop is hypothesized to provide improved transport times .The notional route sized out in the 2013 alpha-level design document was from the Greater Los Angeles Area to the San Francisco Bay Area. That conceptual system would begin around Sylmar, just south of the Tejon Pass, follow Interstate 5 to the north, and arrive near Hayward on the east side of San Francisco Bay. Several proposed branches were also shown in the design document, including Sacramento, Anaheim, San Diego, and Las Vegas.[2]
European routes have been put forward in January 2016. A Paris to Amsterdam notional route was proposed by Delft Hyperloop.[23][24] A Warsaw University of Technology team is evaluating potential routes from Cracow to Gdansk across Poland proposed by Hyper Poland.[25]
Hyperloop Transportation Technologies (HTT) is one group that has been exploring routes other than the Los Angeles to San Francisco route.[26] Another company, Hyperloop One (formerly Hyperloop Technologies), has proposed a route from Los Angeles to Las Vegas.[27]
Observers and analysts have begun to weigh in on some of these potential routes. For example, for the alpha-design notional route, observers have noted that while terminating the Hyperloop route on the fringes of the two major metropolitan areas (Los Angeles and San Francisco) would result in significant cost savings in construction, it would require that passengers traveling to and from Downtown Los Angeles and San Francisco, and any other community beyond Sylmar and Hayward, to transfer to another transportation mode in order to reach their final destination. This would significantly lengthen the total travel time to those destinations.[28] A similar problem already affects present day air travel, where on short routes (like LAX-SFO) the flight time is only a rather small part of door to door travel time. Critics have argued that this would significantly reduce the proposed cost and/or time savings of Hyperloop as compared to the California High-Speed Rail project that will serve downtown stations in both San Francisco and Los Angeles.[29][30][31] Passengers travelling financial centre to financial centre are estimated to save just about two hours by taking the hyperloop instead of driving the whole distance.[32]
Others questioned the cost projections for the notional California route. Some transportation engineers argued in 2013 that they found the alpha-level design cost estimates unrealistically low given the scale of construction and reliance on unproven technology. The technological and economic feasibility of the idea is unproven and a subject of significant debate.[4][5][6][28]
HTT signed an agreement with the government of Slovakia in March 2016 to perform impact studies, with potential links between Bratislava, Vienna and Budapest.[33]
Open-source design evolution
In September 2013, Ansys Corporation ran computational fluid dynamics simulations to model the aerodynamics of the capsule and shear stress forces that the capsule would be subjected to. The simulation showed that the capsule design would need to be significantly reshaped to avoid creating supersonic airflow, and that the gap between the tube wall and capsule would need to be larger.[34][35] Ansys employee Sandeep Sovani said the simulation showed that Hyperloop has challenges but that he is convinced it is feasible.[34]In October 2013, the development team of the OpenMDAO software framework released an unfinished, conceptual open-source model of parts of the Hyperloop's propulsion system. The team asserted that the model demonstrated the concept's feasibility, although the tube would need to be 13 feet (4 m) in diameter,[36] significantly larger than originally projected. However, the team's model is not a true working model of the propulsion system, as it did not account for a wide range of technological factors required to physically construct a Hyperloop based on Musk's concept, and in particular had no significant estimations of component weight.[37]
In November 2013, MathWorks analyzed the proposal's suggested route and concluded that the route was mainly feasible. The analysis focused on the acceleration experienced by passengers and the necessary deviations from public roads in order to keep the accelerations reasonable; it did highlight that maintaining a trajectory along I-580 east of San Francisco at the planned speeds was not possible without significant deviation into heavily populated areas.[38]
In January 2015, a paper based on the NASA OpenMDAO open-source model reiterated the need for a larger diameter tube and a reduced cruise speed closer to Mach 0.85. It also recommended removing on-board heat exchangers based on thermal models from the interactions between the compressor cycle, tube, and ambient environment. The compression cycle would only contribute 5% of the heat added to the tube, with 95% of the heat attributed to radiation and convection into the tube. The weight and volume penalty of on-board heat exchangers would not be worth the minor benefit, and regardless the steady-state temperature in the tube would only reach 30–40 °F (17–22 °C) above ambient temperature.[39]
Musk has allowed that various aspects and subsystems of hyperloop have technology applications to other Musk interests, including surface transportation on Mars and electric jet propulsion.[40][41]
Mars
According to Musk, Hyperloop would be useful on Mars as no tubes would be needed. This is because Mars' atmosphere is about 1% the density of the Earth's.[10][42][43] For the hyperloop concept to work on Earth, low-pressure tubes are required to reduce air resistance. However, if they were to be built on Mars, the lower air resistance would allow a hyperloop to be created with no tube, only a track.[44]Groups acquiring funding and building hardware
Funding to operate prototype Hyperloop vehicles on test tracks are now underway by three companies. Hyperloop Transportation Technologies is building a 8.0-kilometer-track (5 mi) in Quay Valley, California; SpaceX is building a 1.6-kilometer (1 mi)-track in Hawthorne, California; and Hyperloop One is building a test track in North Las Vegas, Nevada.[20][45]Hyperloop One (Previously Hyperloop Technologies)
Hyperloop One announced in February 2015 their plan to develop a Hyperloop route between Los Angeles and Las Vegas. They have organized a board of directors and an engineering team, and have raised more than US$35 million in working capital.[20][27]Hyperloop One consists of over 100 engineers. Shervin Pishevar, a venture capitalist with strong connections to Elon Musk is one of the two co-founders. A lead engineer for Musk's SpaceX, Brogan BamBrogan, is the other co-founder. There are many other connections to Musk throughout Hyperloop One. David Sacks is on the board of directors and he worked under Musk at PayPal. Even though Elon Musk isn’t directly a part of this organization, he is constantly updated.[46]
On May 11, 2016 Hyperloop One conducted the first live trial of Hyperloop technology.[47]
Hyperloop Transportation Technologies
Hyperloop Transportation Technologies (HTT) is a group of 500 part time engineers located across the United States who collaborate through weekly teleconferences. Rather than being paid directly, members work in exchange for stock options. The company is projecting the completion of a technical feasibility study in 2015, but have said that it is at least ten years away from a commercially operating Hyperloop.[26]HTT announced in May 2015 that a deal had been finalized with landowners to build a 5-mile (8 km) test track along a stretch of road near Interstate 5 between Los Angeles and San Francisco.[48] Later in 2015, HTT announced partnerships with Oerlikon Leybold Vacuum and AECOM to assist in the development and construction of the test track,[7] located in the planned community of Quay Valley, beginning in November 2015 and estimated to take 32 months to complete at a cost of US$150 million.[49] Passenger capsules will accelerate to 160 miles per hour (260 km/h), while empty capsules will be tested at the full 760 mph (1,220 km/h).[20][49]
TransPod
TransPod in 2016 introduced a new pod design as a prototype vehicle for field testing. In March 2016, TransPod announced that they will present a full-scale concept vehicle design at the InnoTrans Rail Show in Berlin in September 2016.[50]The TransPod vehicle is planned to target speeds in excess of 1000 km/h, based on computer-driven control, with infrastructure capable of being solar-powered.[51] TransPod has announced a plan to produce a commercial vehicle by 2020.[52] and to work with regulatory agencies for approval of its first hyperloop lines between 2020-2025.[53] The Montreal-Toronto corridor is one of the lines under consideration by TransPod.[54]
TransPod has headquarters in Toronto. It is collaborating with aerospace companies, university researchers, and an architecture firm in Europe. [50] [54] [55] [56]
Hyperloop pod competition
Main article: Hyperloop pod competition
A number of student and non-student teams are participating in a Hyperloop pod competition in 2015–2016, and at least 22 of them will build hardware to compete on a sponsored hyperloop test track in mid-2016.[8]In June 2015, SpaceX announced that they would sponsor a Hyperloop pod design competition, and would build a 1-mile-long (1.6 km) subscale test track near SpaceX's headquarters in Hawthorne, California, for the competitive event in 2016.[57][58] SpaceX stated in their announcement, "Neither SpaceX nor Elon Musk is affiliated with any Hyperloop companies. While we are not developing a commercial Hyperloop ourselves, we are interested in helping to accelerate development of a functional Hyperloop prototype."[59]
More than 700 teams had submitted preliminary applications by July,[60] and detailed competition rules were released in August.[61] Intent to Compete submissions were due in September 2015 with more detailed tube and technical specification released by SpaceX in October. A preliminary design briefing was held in November 2015,[62] where more than 120 student engineering teams were selected to submit Final Design Packages due by January 13, 2016.[62]
A Design Weekend was held at Texas A&M University January 29–30, 2016, for all invited entrants.[63] Engineers from the Massachusetts Institute of Technology were named the winners of the competition. Finishing second was Delft University of Technology from the Netherlands, followed by the University of Wisconsin–Madison, Virginia Tech, and the University of California, Irvine.[8][64] While the MIT team took best overall, Delft University won the Pod Innovation Award.[65] 22 teams will be invited to build hardware and compete in time trials later in 2016 at Hawthorne, California.[8][62]
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