Navigant Research Blog

DeltaWing Offers a Radical Alternative to Vehicle Architecture

— October 6, 2014

Automotive manufacturers are working hard to improve the fuel efficiency of their vehicles without sacrificing internal space, comfort, or performance.  Having concluded that the energy density of battery technology is unlikely to increase enough and prices are unlikely to fall far enough in time to enable them to meet upcoming emissions (CO2) legislation, automakers are investing heavily in technology that delivers greater fuel efficiency in conventional vehicles rather than switching the majority of their fleets to electric or hybrid drive.  Battery electric and hybrid vehicles will continue to be developed and offered, but the gasoline and diesel internal combustion engine (ICE) will remain the primary source of motive power for the foreseeable future, as described in more detail in Navigant Research’s report, Transportation Forecast: Light Duty Vehicles.

Slimmer & Sleeker

In a recent Investor Day presentation by Fiat Chrysler Automobiles (FCA), the company pointed out that CO2 emissions are highly influenced by weight in the EPA’s city drive cycle.  The biggest factor in the highway test cycle is aerodynamic resistance.  Tire drag is the other major factor in both cycles, but it’s much harder to reduce while retaining acceptable ride and handling properties.  So the manufacturers are focusing most of their efforts into weight reduction and aerodynamic improvements.  Most of the changes are incremental, in the hope that many small benefits will combine to make a significant overall improvement.

BMW concluded in the early stages of the development of its electric i3 and i8 vehicles that incremental changes would not give them enough improvement.  Rather than simply exchange the conventional powertrain for a battery and electric motor in an existing model, engineers developed an entirely new architecture for the new range of vehicles, which included new materials, such as carbon fiber, and new manufacturing processes.  Other volume manufacturers have, so far, taken a more cautious route and focused on smaller improvements to components while maintaining current vehicle architecture.

New Look

DeltaWing Technologies is a company best known for developing a radically different racing car that is currently competing in IMSA sports car road races.  It is now looking to partner with major automakers to develop vehicles that will meet and exceed the fuel efficiency targets of the future.  The DeltaWing concept is a radical change from most current road vehicles.  The engine is located at the rear, and the front wheelbase is narrow with thinner tires that reduce rolling resistance without sacrificing road holding.  The distinctive shape has improved aerodynamic properties over conventional vehicle shapes, and the overall design uses lightweight materials extensively.

According to the company, its concept vehicle offers a 35% reduction in overall mass and consumes 35% less fuel for equivalent performance in a four-passenger sedan.  The current performance targets are 0 to 60 mph in about 6 seconds, 130 mph top speed, and up to 70 mpg when using a small displacement, four-cylinder engine producing between 85 and 110 horsepower.  These specifications are clearly attractive to OEMs.  It will be interesting to see if any are prepared to commit to such a radical change.  A more detailed analysis of the options under consideration is included in our upcoming report, Automotive Fuel Efficiency.

 

Automakers Add Gears for Better Fuel Efficiency

— September 3, 2014

Automakers are pursuing many options to improve the fuel efficiency of their cars and trucks.  Most recently, the emphasis has been on reducing weight by changing to less dense materials even though they’re more expensive.   There is also ongoing development work with electrification to recover and reuse kinetic energy.  The latest change to help manufacturers comply with tightening fuel economy targets worldwide is revamping the automatic transmission.

Historically, automatic transmissions were inherently less efficient than manual gearboxes, and convenience was the tradeoff for the loss of a few percentage points in fuel economy and acceleration. Some of the latest automatic gearboxes, though, are actually more efficient than a manual gearbox with a clutch.  Today, the desire to retain complete manual control over gear selection means, in some cases, slightly higher fuel consumption and longer 0 to 60 mph times.  However, a stick-shift generally still saves money off the new sticker price and in North America is sometimes regarded as an anti-theft device.

On Up to 10

From the late 1960s, three speeds was the standard automatic configuration, and it wasn’t until the early 1980s that overdrive and lock-up top gears were added to help improve the efficiency, leading to more four- and five-speed automatic gearboxes.  In 2002, gearbox technology began to get a lot more attention when BMW put the first 6-speed automatic into production, followed by Mercedes with its 7-speed in 2003 and Toyota with an 8-speed in 2007.  Recently there have been a number of transmission announcements:

  • GM is crediting its new 8-speed automatic for making the 2015 Corvette Stingray faster and more efficient.  More gears allows for a lower first gear ratio for better acceleration, as well as a higher final drive ratio to reduce engine speed at highway cruising speed.  The 8L90 transmission will also feature in GM’s range of pickup trucks and SUVs.  Careful packaging and internal design features means that the new gearbox fits the same space as the 6-speed 6L80 – even though it can handle higher torque and power in addition to weighing less.
  • ZF introduced its revised 8-speed transmission in the 2014 BMW 5 Series.  This second-generation 8HP gearbox (the first was introduced in 2009) offers revised gear ratios to take advantage of the latest engine efficiency improvements that deliver more torque at lower rpms.  Advanced torsional vibration dampers improve smoothness, and a new shifting design has reduced internal energy losses.  Other users of the 8HP for rear-wheel-drive cars are Audi, Jaguar Land Rover, and Chrysler.
  • Chrysler is building a 9-speed transmission under license from ZF.  It went into production at the end of 2013 in the Jeep Cherokee.  ZF also supplies the 9HP for the Range Rover Evoque.  Chrysler is planning to implement a version in its minivans and smaller front-wheel-drive cars, as well.  Although the wider ratios provide better fuel economy and acceleration, concerns have been raised about erratic shifting.  These are being addressed via a software update.
  • In September 2013, Mercedes launched its 9G-TRONIC transmission on the E 350 BlueTEC diesel saloon car.  Despite two additional gears and a higher maximum torque, the new automatic transmission requires no more installation space than its predecessor and is also lighter.  The torque converter housing is made of lightweight aluminum, while the transmission housing with plastic oil pan is made of an even lighter magnesium alloy.

Ford and GM have already announced that they are planning to develop a 10-speed gearbox together.  It seems that manufacturers have figured out how to get more ratios in the same space and, at the same time, reduce internal energy losses so that efficiency is higher while maintaining or improving performance.  The key is integration with the latest engine characteristics to optimize the driving experience.  This topic will be covered in more detail in our upcoming report on automotive fuel efficiency.

 

Government Accelerates Autonomous Vehicle R&D in the United Kingdom

— August 14, 2014

At the end of July, the British government made a commitment to support the development of self-driving vehicles in the United Kingdom.  Up to three cities will be selected to host trial projects beginning in 2015, and they can apply for a share of a £10 million ($16.8 million) fund established to kick-start new investment in automotive technology.  The press release said that “Ministers have also launched a review to look at current road regulations to establish how the UK can remain at the forefront of driverless car technology and ensure there is an appropriate regime for testing driverless cars in the UK.”

The United Kingdom already has one of the world’s first autonomous vehicle shuttle services, which went into operation in 2011 serving Heathrow Airport’s Terminal 5.  A pilot scheme for fully autonomous pods in Milton Keynes was announced in November 2013.  And the Mobile Robotics Group at Oxford University is building its reputation as an advanced research organization in driverless vehicle technology.   Having the government working on legislation and helping to fund pilot programs is an important step forward in promoting the technology and attracting business to the country.

Unfortunately for the United Kingdom, though, the majority of engineering development work at the major European automakers takes place in Germany and France.  Ford still has an engineering center in Essex, but it’s much smaller than its sibling near Cologne, Germany.  Revised legislation and multiple testing areas in the United Kingdom may well inspire some companies to establish new satellite development centers in the country in the same way that they did in California when Google’s pioneering work began to get headlines a few years ago.  On the other hand, it may also spur governments on the European continent to introduce similar efforts in their countries.

Multiple Routes

One thing to bear in mind with this technology is that there are multiple streams of applications.  In the short term, there is the task of developing a more integrated approach to the individual advanced driver assistance systems functions that are already in production to be able to offer drivers help in well-defined situations such as cruising on a motorway or shuffling along in congested traffic jams.  Mercedes has already begun offering its Intelligent Drive on the new S-Class, and its competitors are not far behind.  Most promise something similar in the next couple of model years.  More fully automated systems that can follow instructions from a navigation system under limited circumstances are expected from about 2020 on, with full automation coming to market after 2025.  The United Kingdom could become a popular place for manufacturers to test such vehicle systems.

The other route is to go directly to small self-driving vehicles that operate at low speed (<25 mph) and with a limited range.  In the early days, these will only operate on roads or paths where conventional vehicles are prohibited.  These projects will have to be initiated by local governments rather than the automakers, and they will provide valuable practical experience of the benefits and challenges that autonomous vehicles can bring to a city or community.

 

In China, Cars Learn the Roads

— August 5, 2014

Navigant Research’s recent report, Autonomous Vehicles, focused on the activities of large global automakers, Tier One suppliers, and universities and research organizations (including, of course, Google) in Western Europe and North America.  Extensive work is also happening in Japan, and the Japanese automakers are among the companies providing a steady stream of interesting automotive engineering news.

Not so much is heard about what’s going on in China.  The rapid growth in vehicle sales in that country gets most of the headlines, along with the accompanying congestion and air pollution.  But, like Northern California, China also has a tech company that has built its fortune from an Internet search engine and has branched into R&D on self-driving vehicles.  Sometimes referred to as China’s Google, Baidu revealed in July that it’s working on what it calls a highly autonomous car.

Unlike the Google car that famously has no steering wheel or foot pedals, the Baidu concept will be a conventional vehicle with a driver when the first prototypes are shown in 2015, but it will have plenty of intelligence and awareness built in.  The best way to think about it is to consider an earlier form of personal transportation: the horse.  The rider gives instructions about when to start and stop and turn, but the horse knows to avoid obstacles and dangerous situations and can learn familiar routes and navigate itself through traffic.  This is a very different approach to the Google model, which requires highly detailed digital maps of every road before it can venture out.

Affordable Autonomy

The only other developer I have heard contemplating this approach is the Australian startup Zoox, which I mentioned in a previous blog.  Baidu is also reportedly working on a driverless bicycle that will be able to deliver packages as well as provide mobility to those unable to drive.  A prototype is slated for demonstration by the end of this year.

The Chinese approach is an interesting alternative to the high-tech and likely high-cost options for self-driving being developed in the rest of the world.  One of the keys to success in the mass market is affordability.  Another obstacle to the rollout of autonomous driving, in the West, is legislation.  In China, the government can act very quickly to support the modification of laws to allow driverless vehicles to operate on public roads if it deems the technology ready and the benefits are clear.

Chinese car makers have struggled to break into Western markets, typically finding it difficult to meet the extensive crash safety specifications required in the European Union and the United States.  They’ve had more success exporting to other countries in Eastern Europe, Latin America, and the Middle East.  In all these regions, getting permission to offer semi-autonomous vehicles could prove relatively easy, and the potential benefits for safety and traffic flow are even bigger than they are in the high-profile Western countries.

 

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