What are tiny leaning cars?

carver car
The three-wheeled, Carver brand leaning car. See more small car pictures.
Carl de Souza/AFP/Getty Images

Three billion cars will flood the world's roadways by the year 2035, according to the economic forecasting firm Global Insight [source: Global Insight]. Major cities, which are already battling congestion, may not be able to handle that influx of traffic without a major overhaul of the infrastructure. For instance, Forbes Magazine ranked Atlanta, Georgia, as having the worst commute problems in the United States in 2008, with drivers spending 60 hours a year gridlocked on the highway [source: Woolsey].

Enter tiny leaning cars. These three- and four-wheeled vehicles are designed to alleviate these growing traffic problems in urban areas. How do they plan to do that? It's all about size. Many people drive five-passenger cars to and from work but they only carry themselves. With that in mind, tiny leaning cars have minimal space for one or two people to eliminate the wasted space of regular sedans.


­And when we say "tiny," we mean it. If you've seen people zipping around in pea-sized Smart Cars, NARO brand tiny leaning cars are even smaller. By arranging the two seats in a row rather than side-by-side, the executive commuter models are just over 3 feet (1 meter) wide. That makes them almost 2 feet (0.6 meters) skinnier than Smart Cars.

So what's the deal with the "leaning?" Despite the name, you can think of tiny leaning cars as cross-breeds between motorcycles and cars. NARO cars, in development by the Narrow Car Company, have four wheels, but at higher speeds use the same tilt system that motorcycles do when they hug curves and corners. The passenger compartment actually shifts with the leaning motion as though riding a motorcycle around a corner to help control the vehicle's center of gravity and keep the wheels stable on the ground.

Where does this fit in with the traffic congestion problem? The Narrow Car Company envisions them being used to scoot in between stalled lanes of traffic, much like cyclists can do, if lane splitting is legal in their state. But the enclosed compartment offers a safer means of travel. And, oh yeah, they get 100 miles to the gallon.

On the next page, we'll take a closer look at the NARO design and a three-wheeled leaning car.



How the Tiny Leaning Car Works

grand prix racer
Tiny leaning cars use the same physics principles as motorcycles to hug curves.

Because of the height and the slim width of the NARO tiny leaning car, the lean factor is actually an added safety measure. At higher speeds without the lean, there would be a greater risk for the vehicle to flip over. Instead, the NARO has a patented system that restricts the lean capability at low speeds and automatically engages it when you go faster. The car borrows the same physics principles that motorcycles use when they hug turns.




The two driving modes that allow for the upright driving and the lean are called roll-stiff pro-steering and free-leaning counter-steering, respectively. Since the NARO shifts between these for you, drivers don't have to worry about when to engage the leaning factor.

Since tiny leaning cars are a lot like motorcycles, it makes sense that the term "counter-steering" comes up. Counter-steering is the way you navigate on a motorcycle when you lean on the side of the handlebars in the opposite direction you want to go. For more detailed information about motorcycles, read How Motorcycles Work. But unlike the two-wheeled vehicle, the NARO computer that regulates the different steering modes also allows the driver to continue steering as usual even during the free-leaning mode. The passenger compartment will lean to the left or right, depending on the direction it is cornering.

How safe are these car-motorcycle combos? A steel cage skeleton covered with thermoplastic panels encloses the passenger compartment. These crash panels are similar to those in regular cars [source: Sampson]. Designers have also integrated airbags into the body for increased protection. Thanks to the size of the car and the materials, it weighs a mere 771 pounds (350 kilograms). Since it's so light, its position close to the ground and the leaning help prevent it from flipping over.

One three-wheeled leaning car that has officially hit the market in Europe is the Carver One. The Carver One looks like the back of a compact sedan married to the front of a motorcycle. Carvers have a driver-passenger arrangement similar to that of the NARO, only the interior and exterior look a bit more luxurious. But rather than eco-friendliness, Carver stresses the fun of skimming around turns and taking advantage of its responsive suspension and lean.

These design hybrids have two stationary back wheels and a free-tilting passenger compartment and front wheel. Its patented Dynamic Vehicle Control system that combines hydraulics and electronic fine-tuning allows for this movement [source: Carver Engineering]. Like the NARO, the Carver One has a steel cage along with the outer paneling and seat belts for safety. It also has passed the European Union road approval certification where it's on sale and pending approval overseas.

One drawback of the Carver One, however, is its fuel economy. Getting only 40 miles per gallon, it barely outpaces sedans on the road. That issue may partially relate to its size, weighing nearly twice that of the NARO.

For more information about tiny leaning cars and other future auto, visit the links on the next page.




Lots More Information

Related HowStuffWorks Articles

More Great Links

  • Discovery Channel. "The Body." FutureCar. Feb. 14, 2007.
  • Global Insight. "Demand for Cars and Trucks to Quadruple at Current Trends by 2035." June 2008. (June 24, 2008) http://www.globalinsight.com/PressRelease/PressReleaseDetail12968.htm
  • Kemp, Hugh and Harty, Damian Andrew. "Laterally-leaning vehicle." European Patent Office. EP 1 702 773 A2. Sept. 20, 2006. (June 24, 2008). http://v3.espacenet.com/origdoc?DB=EPODOC&IDX=EP1702773&F=0&QPN=EP1702773
  • Sampson, Ben. "Lean machine." Professional Engineering. March 8, 2006.
  • Sawyer, Christopher. "Lean Mobility." Automotive Design & Production. July 2006. (June 24, 2008). http://www.autofieldguide.com/articles/070603.html