15 FUTURE Train Concepts and Designs

From magnetic trains that float above their tracks to hydrogen-powered engines that leave nothing but water behind, the future of rail travel is already taking shape, and around the world, engineers are reinventing how we move, making trains faster, cleaner, and smarter. These are 15 future train concepts that show where transportation is headed next. Let's start with number 15, JR Central's Maglev, the Chuo Shinkansen in Japan. JR Central, or Japan Central Railway Company, is building one of the most advanced train systems in the world, the Chuo Shinkansen. This is a superconducting maglev, or magnetic levitation line, that's designed to connect Tokyo and Osaka at speeds of up to 314 miles an hour. The project has been in development for decades, with the origins tracing back to research in the 1970s. Now, these use superconducting magnets that are cooled with liquid helium to create these stable magnetic fields that lift the train several centimeters above this U-shaped guideway. Once it's levitated, linear motors embedded in the track propel it forward, smoothly and silently. The result is an ultra-fast, low-maintenance transportation system that's capable of traveling from Tokyo to Nagoya, that's about 300 kilometers, in just 40 minutes, and eventually on to Osaka in 67 minutes once the full route's complete. Construction started in 2014, and the first segment between Tokyo and Nagoya is expected to open by 2034, though delays have happened due to environmental concerns and some opposition from local governments. Around 86% of this route will run underground, some requiring the most complex tunneling work ever attempted. JR Central's already built a test track, where trial runs have repeatedly broken speed records for passenger trains, and in 2015, a seven-car train reached a speed of 375 miles an hour, a world record for rail vehicles. These tests have also focused on safety and passenger comfort, ensuring that even at extreme speeds, they remain smooth. But the costs here are pretty staggering. It's estimated at over 9 trillion yen, that's about 60 billion US dollars, for the first phase. It represents a major leap forward in the intercity travel technology here. It's not science fiction, it is the next generation of Japanese rail travel. It's already under construction, and when it finally opens, it will redefine what high-speed transportation can be. 14. The Virgin Hyperloop In The United States So, the Virgin Hyperloop was formerly known simply as Hyperloop 1. It's one of the most ambitious concepts. It was an attempt to combine the efficiency of rail with the speed of air travel. It's based on an idea first outlined by Elon Musk in 2013, passenger pods traveling through a near-vacuum at high speeds using magnetic levitation. Well, Virgin Hyperloop, founded in 2014 and backed by Richard Branson's Virgin Group, became the leading company working to turn that concept into a reality. This whole system, theoretical though, starts by placing passenger pods, or cargo pods, inside sealed vacuum tubes with air pressure reduced to about one-thousandth of the Earth's. This near-vacuum dramatically cuts the air resistance, allowing the pods to reach theoretical speeds of 620 miles per hour. Virgin Hyperloop built a full-scale test track called the Devloop in Nevada Desert in 2017, and in 2020, it made history when two company employees became the first humans to ride the Hyperloop. Their pod traveled 500 meters and reached about 107 miles per hour. It is a proof-of-concept run that does demonstrate that passenger travel inside a vacuum tube was not only possible, but safe. But the infrastructure costs here are massive, way higher than those for regular maglev systems, and as a result, most of Virgin Hyperloop's current efforts have shifted towards cargo transport, which faces fewer regulatory and safety challenges than human travel. In 2022, though, Virgin Hyperloop laid off much of its passenger development team, and they focused on freight routes instead. Governments in the United States, India, Saudi Arabia, they've all studied the possibility of developing these Hyperloop corridors, and prototype facilities continue to explore new ways of making this viable. If it can overcome the cost, the safety, and the infrastructure barriers, the Hyperloop could one day make cross-country travel faster than airplanes, and as frequent as subway service. For now, though, it's a bold, verified experiment in reimagining what train travel could actually be in the 21st century. 13. THE TRANSRAPID SHANGHAI MAGLEV THE WORLD'S FIRST COMMERCIAL MAGLEV IN CHINA When the Shanghai Maglev opened in 2004, it did become the first full-scale commercial magnetic levitation train in the world. It was built using German Transrapid technology developed by Siemens and ThyssenKrupp. This line still holds the title as the fastest commercially operating train on the planet. It reaches speeds up to 268 mph during daily service. It can also reach 311 mph during testing. The 19-mile-long line connects Longyang Road Station in Shanghai with Pudong International Airport, and it completes this journey in just 7 minutes and 20 seconds. Construction began in 2001, and the whole project was a technological showcase. It was completed in just over two years at a cost of around $1.2 billion. The German and Chinese teams worked together to design not just the track and vehicles, but also an entirely new operations system. Though the line is pretty short, it does serve as kind of a testbed for maglev technologies. It accelerates to top speeds within seconds, and because there's no contact with the track, the vibration is nearly eliminated. Passengers report an exceptionally smooth and quiet ride compared to conventional trains. But the major limitation here has been the short distance and the high cost, because the line only connects the airport to the outskirts of the city. Ridership is pretty much below expectations. Plans to extend the route to central Shanghai and beyond were proposed several times, but postponed due to budget constraints and public concern over electromagnetic field exposure, though studies have found no proven health risk. Well, two decades later, it still operates daily, carrying millions of people each year. It shows how far magnetic levitation has come from lab testing to a commercial reality. 12. The Alstom Caradia Eiland – The Hydrogen-Powered Train in Germany I didn't know about this one until we did research on it. The Alstom Caradia Eiland, developed in Germany and launched in 2018, is the world's first hydrogen fuel cell-powered passenger train. Instead of diesel engines or overhead wires, this one uses hydrogen that's stored in onboard tanks, which react with oxygen in a fuel cell to produce electricity, emitting only water vapor as a byproduct. It was designed and built by the French transport company Alstom. The Eiland was first introduced in Lower Saxony, Germany, as part of a pilot project for regional rail. Two prototypes entered service in 2018 on a 100-kilometer route that replaced diesel units on a non-electrified line. The trains quickly proved successful, achieving speeds of 87 miles an hour with a range of about 620 miles per hydrogen fill. In 2022, the state of Lower Saxony expanded this program, and they deployed a fleet of 14 hydrogen trains, effectively making it the first region in the world to operate on an entire line powered solely by hydrogen. Countries including France, Italy, Austria, and Canada have tested and ordered versions of this train. Its design not only aims to cut carbon emissions but make rail transport more adaptable in rural or secondary networks where building electric infrastructure is too expensive. The Eiland shows that the future of trains might not just be about going faster, it might be about going cleaner. It combines modern engineering with environmental responsibility, proving that hydrogen can be practical and scalable. It's an alternative to diesel. For Europe, where decarbonization goals are pushing every mode of transport towards sustainability, the Eiland is a real-world example of how that transformation can happen on the rails. 11. SNCF TGV-M – France's Next Generation High-Speed Train The TGV-M, also known as Avelia Horizon, is the next step in the evolution of the country's legendary high-speed rail network. Developed by Alstom for France's National Railway Company, this train represents a new generation of energy-efficient, modular, and digitally connected trains. It's scheduled to enter service in 2025 to replace older TGV duplex trains and set a new standard for performance. Compared to previous models, this one's expected to use about 20% less energy while accommodating 20% more people, thanks to improved aerodynamics and lighter weight materials. Each train can reach speeds of up to 199 miles an hour and consists of two power cars and a modular passenger car. Digitally speaking, the TGV-M is a leap forward. It's equipped with advanced onboard diagnostics and real-time monitoring, allowing engineers to detect and prevent any potential issues, and this kind of predictive maintenance approach is expected to cut life-cycle costs by about 30% compared to older trains. And of course, the cabins are designed with modern comfort in mind, more spacious interiors, wider doors, improved Wi-Fi coverage, which is great to game on, and quieter rides. Environmentally speaking, it is one of the cleanest electric trains, built to be 97% recyclable, and it aligns with France's push for a greener transport system. With its blend of engineering, design, and sustainability, this one shows that the future of high-speed rail isn't only about faster speeds, it's about smarter, cleaner, and more flexible travel. Just like the original TGV revolutionized European rail in the 1980s, the TGV-M is poised to define the next era of high-speed mobility. 10. CRRC 600kmh Maglev Prototype In July of 2021, China Railway Rolling Stock Corporation unveiled its next-generation 600kmh Maglev train, the fastest ground vehicle ever built at full scale. Unlike conventional high-speed trains, this system uses electromagnetic levitation, meaning the train floats above the guideway and during testing, it showed consistent operation above 373 mph, making it faster than any commercial aircraft on short routes, once the station time and airport procedures are considered. At this speed, a trip between Shanghai and Beijing, over 1,000 kilometers, could take just 2.5 to 3 hours, compared to more than 5 hours by high-speed rail or over 4 by air. The prototype features a lightweight carbon fiber and aluminum alloy body, a fully enclosed low-drag nose, and high-efficiency superconducting magnets. It is designed for eventual use on intercity routes that are shorter than 1,500 kilometers, where ultra-high-speed service could replace domestic flights. And, of course, challenges remain. Maglev systems require entirely new tracks, expensive infrastructure, and complex control systems. Despite that, China does view the technology as important for national development. The country's engineers have already built several lower-speed Maglev lines, including the Changsha Maglev Express and the Beijing S1 line. Those both were used as testbeds for safety and automation. At 600 kilometers per hour, this Maglev doesn't just represent the future of trains, it represents the future of land travel itself. It's smooth, silent, and faster than anything that's ever touched a track. 9. SPAIN'S ULTRA-FAST, ULTRA-EFFICIENT TRAIN, THE TALGO AVRIL Spain has been at the forefront of high-speed rail for a while, and the Talgo Avril is the next evolution of that success story. This new generation of high-speed train is designed to reach speeds of about 224 miles an hour, that's 360 kph, making it the fastest train ever developed in Spain. Its name, Avril, stands for High-Speed Lightweight Independent Wheel, but in Spanish, since I can't pronounce all that. This design prioritizes three things, speed, efficiency, and capacity. It's built with a lightweight aluminum body that reduces energy consumption by around 30%, and each train set has 12 passenger cars, offering 581 seats, making it one of the highest-capacity high-speed trains. One defining feature is the independent wheel system, where each wheel turns separately rather than being connected by an axle. This kind of feature reduces wear and improves stability at high speeds, and it allows the train to adapt to different track gauges, a major advantage in Spain, where high-speed and conventional rail networks use different widths. In terms of performance, tests have already confirmed that the reliability at sustained speeds is 360 kph, and it's certified for operation on both 25-kilovolt AC lines and 3-kilovolt DC lines. Its introduction does mark a new stage for Spanish rail. The combination of speed and design and cross-network compatibility gives Spain one of the most advanced high-speed rail systems in the world. By blending Spanish innovation with practical design, this one shows that high-speed rail can be both fast and flexible. It's a train not only built for the future of Spain, but for the next era of European mobility. 8. The Hitachi Bombardier High-Speed 2 The HS2 train, officially known as the Hitachi Bombardier AT300 high-speed train, is the United Kingdom's most ambitious rail project in more than a century. Manufactured jointly by Hitachi Rail and Alstom, which acquired Bombardier Transportation, the HS2 trains will be capable of 225 mph, matching the fastest trains in Europe. Each train is going to be about 200 meters or about 650 feet long and able to operate in pairs to double capacity. This kind of design takes inspiration from Japan's Shinkansen and Europe's TGV. This streamlined nose and smooth underbody will minimize drag. The trains will be fully electric, powered entirely by renewable energy sources, and they're being built to exceed European safety standards with noise reduction technology, regenerative braking, and compatibility with both the new tracks and the existing UK rail network. The goal is to make train travel faster than domestic flights between the major British cities while offering a lower carbon footprint and a greater convenience. The overall network budget, though, has risen to well over £70 billion, and in 2023 parts of the northern extension were paused due to political and economic pressures. However, construction of the southern section between London and Birmingham is still advancing, and the first trains are expected to begin testing in the late 2020s. When completed, this will mark the UK's return to the forefront of high-speed rails. Its trains will not only rival those in France and Japan, but they will showcase how clean electric mass transport can be. Whether viewed as an engineering marvel or a massive infrastructure challenge, the HS2 trains are the most advanced ever built for Britain. It is a glimpse of the country's transport future on rails. 7. SIEMENS VALERO NOVO GERMANY'S ULTRA EFFICIENT HIGH-SPEED TRAIN Germany's Siemens Valero Novo is one of the most advanced trains ever developed. It's an evolution of the famous Valero family, which includes trains used for Spain's AVE, Russia's SAPSAN, and Britain's Eurostar E320. Unveiled in 2018, the Valero Novo was designed to set new global benchmarks for speed. Now, it is capable of speeds up to 224 mph, but its real breakthrough is in its energy efficiency and modular design. Compared to the previous Valero D model, the Novo uses 30% less energy while providing 10% more seating capacity. Siemens achieved much of this by starting from scratch. Engineers developed a completely new car body based on ultralight aluminum shells that reduce weight by 15%, and the bogies, motors, and drive systems were all also redesigned to be more compact and accessible for maintenance. This empty-tube concept is one of the most distinctive innovations. The train's underfloor components are entirely sealed within a smooth, aerodynamic surface that reduces drag by up to 20%. That design, combined with regenerative braking and high-efficiency traction, gives it one of the lowest energy consumptions of any train in its class. And the interior was also built for the next generation of travel. Noise levels have been reduced, passengers can enjoy panoramic windows, real-time travel information, and fully digital systems for climate control and lighting. This one is expected to form the backbone of Germany's future high-speed network in the 2030s, particularly as Deutsche Bahn continues to expand its ICE services, or Intercity Express service. Beyond Germany, though, Siemens has marketed the Novo as a global platform. It is a train that reflects Germany's commitment to precision over spectacle. A model not built for record-breaking speeds, but for long-term sustainability. 6. The Zafiro Express Sweden's new generation of Arctic-ready high-speed trains. Way up there in the north of Europe, where the freezing temperatures and snow can bring transport to a standstill, Sweden is preparing for its own leap forward in train design. The Zafiro Express, developed by Alstom for Swedish Railways, is a new class of high-speed train that's built to handle the harshest Nordic conditions. Announced in 2022 and expected to begin service around 2026, connecting cities like Stockholm, Gothenburg, and Malmö, and later extending into neighboring countries Norway and Denmark, these trains will run at speeds of up to 155 mph. Not the fastest in the world, but engineered to operate flawlessly in climates where temperatures can be negative 40 degrees Celsius. The exterior of it is heavily insulated, the undercarriage is fully enclosed to prevent any ice buildup, and the doors and couplings are reinforced against snow intrusion. Even the air intakes and braking systems are adapted to ensure safe operation in these blizzard conditions up there. Each 250-meter-long train set will include eight cars, offering seats for up to 363 passengers, and inside the design focuses on quiet operation and comfort during long-distance journeys. Digital connectivity, of course, on-board Wi-Fi and USB charging at every seat comes standard, aligning with SJ's commitment to passenger-friendly rail modernization. The Zafiro Express is fully electric with 95% recyclable materials and regenerative braking that returns energy to the grid, and the streamlined nose and lightweight materials will reduce aerodynamic drag and power consumption. This is going to help Sweden get to its goal of achieving a fossil-free transport sector by 2040. And besides, Alstom's partnership with SJ represents one of the most significant train investments in Scandinavian history. This is valued at around 650 million euros for 25 train sets. In an era when railways have to adapt to climate and energy transition, Sweden's new flagship train shows that the future of high-speed travel can thrive in even the coldest corners of the world. 5. SHINKANSEN N700S – JAPAN'S SUPREME BULLET TRAIN Known as the Supreme, the Shinkansen N700S is Japan's latest generation of bullet train. Introduced in 2020 by JR Central, it runs primarily in the Tokaido Shinkansen lines between Tokyo, Nagoya, and Osaka. Capable of speeds of up to 224 miles an hour in testing, and operated at about 285 kilometers an hour in daily service, the N700S is lighter, smarter, and quicker than the previous A-series. They redesigned the train's structure to reduce its weight by 11 tons per 16-car set, which did improve acceleration and energy efficiency. One of its standout features, though, is the lithium-ion battery self-propulsion system, which is a first for any high-speed train in the world. In the event of a power outage or earthquake, which is common there, the train can continue moving under its own battery power for several kilometers, allowing it to stop safely at the nearest station, instead of being stranded between tunnels or bridges. The interior reflects the comfort Japan's railways are famous for. Seats feature more recline and legroom, LED lighting adjusts automatically with the time of day, and advanced suspension systems create a really smooth ride even at top speeds. In 2021, this train became Japan's new global export platform, with versions under consideration for countries like Taiwan and the United States. The modular design does make it easier to adapt for different power systems and regulations. For Japan, the N700S is not just a technological advancement, it's a symbol of their reliability. Every trip is timed to the second, with average annual delays in trains measured in fractions of a minute. It is a train that was built to serve a nation that treats precision as both an art and science. 4. ITALY'S RED ARROW OF THE FUTURE Italy's ETR1000 Frecchiarossa, or Red Arrow, is one of Europe's fastest and most elegant trains. Built by Hitachi Rail Italy and Alstom, it's been in service since 2015, and it's known for combination of speed, comfort, and sustainability. It can reach speeds of 249 mph, that's 400 kph, in testing, and it operates commercially at about 186 to 224 mph. It's powered by eight self-propelled cars, each with its own traction motors, which allows excellent acceleration and braking. Designed for both speed and passenger experience, the interiors are divided into four classes, executive, business, premium, and standard. The executive cars feature leather recliners, full meal service, and conference-style seating, while the standard cars do offer wide seats, quiet cabins, and Wi-Fi throughout. And of course, LED lighting, noise reduction tech, and active suspension all create a smooth and quiet ride. The train is 95% recyclable and equipped with regenerative braking that returns up to 15% of its energy to the power grid. The noise emissions are well below the EU limits, and the aerodynamics reduce power use by about 30%. In 2021, Trenitalia, Italy's state-owned rail company, expanded operations to Spain, running this on service routes through Madrid-Barcelona, Madrid-Seville, and the train is fully compliant with European interoperability standards, meaning it can operate across multiple countries without any technical modifications, which is an advantage for cross-border trains. Competing directly with short-haul flights, it does offer faster boarding, city-center-to-city-center service, and a significantly smaller carbon footprint, and in Italy, it's already helped reduce domestic air travel on key routes by over 40%. For passengers, though, it is a glimpse into what the next generation of rail traffic will feel like, swift, quiet, and beautifully engineered. 3. The AGV Italo, Europe's First Next-Generation Composite High-Speed Train The AGV Italo, operated by NTV in Italy, holds a special place in European railway history. It was introduced in 2012 and was the first commercial train built using Alstom's AGV platform. This is a fully-distributed power design that broke from decades of tradition. With its carbon fiber components and record-breaking speed, it is one of the most efficient and advanced trains ever to run on European rails. Unlike earlier models like the French TGV, which relies on power cars at each end, the AGV distributes traction motors along the entire train. Each train set, typically about 11 cars long, can reach speeds of 224 mph, or about 360 kph. They do have a world-record run of 357 mph, or 574 kph, during a prototype testing in 2007. It's still one of the fastest speeds ever recorded for a wheeled train. The body itself is built from aluminum and composite materials, which reduces its mass and improves its performance. But inside, the passenger experience rivals business-class air travel. It features four classes – Club Executive, Prima, Smart, and Smart Cinema – with leather seats, Wi-Fi, touchscreen entertainment, and on-demand catering. And of course, all the cabins use LED lighting and low-noise interiors. This train operates on Italy's high-speed network that connects Milan, Rome, Naples, Venice, and Turin, and it competes directly with Trenitalia's Frecchia Rosa. Despite being a privately operated service, which is unusual in Europe's high-speed landscape, it's thrived, capturing a share of the market from airlines by offering frequent and luxurious service. It's faster, lighter, greener, and smarter than its predecessors. And instead of chasing extreme speed records, it achieves balance by combining comfort, sustainability, and efficiency in a way that defines what modern high-speed travel should be. 2. The Hyperloop So, the Hyperloop Transportation Technologies, Hyperloop TT. This was a project that represents one of the most advanced efforts to transform futuristic Hyperloop idea into an operational transport system. Founded in 2013 and based in Los Angeles, Hyperloop TT is developing a passenger and cargo transport system that moves pods through vacuum tubes, using maglev and electric propulsion. The company's system does use a passive magnetic levitation known as InductTrack, which is a technology originally developed at Lawrence Livermore National Lab. Instead of relying on superconducting magnets or complex active systems, InductTrack uses permanent magnets arranged in specific patterns that allow the pod to levitate only while moving. They've built a 320-meter full-scale test track in France where it's conducted levitation and vacuum tests since 2019. The passenger capsule, the Quintero 1, measures about 32 meters or 105 feet long and weighs about 5 tons. And it's made almost entirely from a composite material, specially developed carbon fiber and reinforced polymer that's lightweight and extremely strong. It is designed to carry about 30 to 40 passengers and travel at speeds of over 600 miles an hour in near-vacuum conditions. Because the pods are in that low-pressure environment, they do face minimal air resistance, which requires way less energy to maintain the high speeds. And in 2020, they signed agreements to begin feasibility studies for routes in Italy, the United States, and the United Arab Emirates, including a proposed Abu Dhabi-Dubai corridor. However, as of today, its systems remain in the prototype and certification stage, and no commercial passenger service has yet been launched. While there is still uncertainty about regulatory approval, passenger comfort at high speeds and long-term costs, Hyperloop TT is one of the few projects with full-scale hardware and a functioning test facility. If it's successful, and that's a big if, it could drastically shorten intercity travel times, turning what is now a five-hour trip into less than one hour. 1. THE JAPAN-CHINA MAGLEV RACE – THE FUTURE OF SUPERCONDUCTING RAIL So, let's change the pace up a bit when it comes to pushing the limits of ground transportation. No rivalry has captured the world's attention quite like the quiet high-speed competition between Japan and China. Both nations are racing to perfect maglev trains. Their projects represent not just the future of rail travel, but a glimpse into a world where long-distance travel is faster, cleaner, and quieter than ever imagined. Japan's journey began more than half a century ago, in the 1960s. Engineers at Japan National Railway started experimenting with maglev as a way to surpass the 199-mile-an-hour limit of traditional steel wheels. Today, Japan is one of the most advanced and high-tested high-speed train technologies in existence. The trains use superconducting magnets cooled by liquid helium to near absolute zero, creating a strong, stable magnetic field. These fields can generate both lift and propulsion, allowing the train to levitate about 10 centimeters above the guideway and move forward without any physical contact. The result is near-zero friction and an incredibly smooth motion. Testing on the Yamanashi Maglev test line in central Japan began in 1997, and by 2015, the project had already achieved a world-record speed of 375 miles an hour. That record still stands, and at those speeds, passengers experience almost no noise or vibration, only a steady glide that feels more like a flight than rail travel. The eventual goal is to operate at 314 miles an hour commercially, carrying passengers between Tokyo and Nagoya in just 40 minutes, cutting the current Shinkansen time in half. As of today, 2025, the Tokyo-Nagoya section is expected to open around 2034, though the local opposition over groundwater concerns has caused some delays. Despite the obstacles, though, it remains a national priority and a point of pride. JR Central, the company behind the project, believes that this technology could eventually be exported globally. One proposed route would connect Washington DC and New York City, reducing the trip to just one hour. Meanwhile, in China, it's rapidly emerged as Japan's main competitor in the space. Having learned from both German and Japanese systems, China Railway Rolling Stock Corporation developed its own homegrown high-speed maglev, unveiled in 2021. This new prototype achieved the same 373 mile an hour top speed as Japan's record breaker, signaling that the two countries now stand neck and neck in the race for the fastest train on Earth. China's maglev uses electromagnetic suspension, EMS, rather than superconducting technology, which makes it cheaper and easier to maintain, though slightly less efficient at extreme speeds. It builds on the success of the Shanghai Maglev, which operated reliably since 2004, and it still runs at about 268 miles an hour on its 30-kilometer route to Pudong Airport. Both Japan and China do see maglev as not merely a transport, but strategic infrastructure. It's symbols of innovation and global influence. China's electromagnetic maglev focuses on scalability, aiming to build new routes faster and integrate them. Japan's maglev emphasizes ultimate smoothness and stability, and long-term reliability. For passengers, the appeal is obvious. City center to city center travel faster than a plane, quieter than a car, and more reliable than any other mode of transport. Boarding it will feel like entering a futuristic aircraft, but one that glides silently rather than takes off. But of course, challenges remain. The infrastructure costs are huge. Tunnels, power systems, and guideways drive up construction budgets into the tens of billions of dollars. For this reason, widespread adoption outside East Asia has been slow, though research partners are growing in Europe and the U.S. As the 2030s approach, the competition will likely define the future of global high-speed travel. Whether Japan's superconducting precision or China's mass production efficiency prevails, both systems point towards the same vision. A world where flying across a continent might one day mean gliding silently on rails just above the ground. In that sense, the Japan-China maglev race isn't just about who has the fastest train. It's about who gets to shape the future of transportation itself.