On the smart fortwo

The smart fortwo is designed to be a car for the urban environment: realize that it is just 105.9 inches long and is powered by an 89-hp three cylinder engine. While it can be driven on a freeway, clearly the city is where it is more at home.

One of the concerns that people may have with a smart fortwo is its level of safety in an environment where there are significantly larger vehicles on the road. So Mercedes-Benz decided to perform a crash test of a fortwo with a Mercedes S-Class. This test was at an impact speed of 50 km/hr and 50% frontal overlap. The mass of the fortwo: 2,478 lb. The mass of the S-Class: 5,080 lb. In terms of the materials used to construct the cars, the fortwo is 51% high-strength steel, 13% ultra-high-strength steel, and 8% hot-formed steel. The S-Class is 14% aluminum, 55% high-strength steel, 10% ultra-high-strength steel, and 12% hot-formed steel. According to Prof. Rodolfo Schöneburg, head of Vehicle Safety at Mercedes-Benz Cars, “The well-proven tridion cell forms the basis for the high crash safety of the new smart. It ensures efficient energy absorption, for example, in
a frontal impact. To this end, the crumple zones of the new smart have been made as large as possible. Homogeneous application
of force in the structure is achieved with several loads of paths.” Schöneburg added, “The high proportion ultra-high-strength steels ensures high stability for the passenger cell.”

The smart fortwo is manufactured in Hambach, France, in a complex that’s centered on a central assembly building that’s shaped like a plus sign: the long external arms of each of the branches allows the feeding of modules and parts to the assembly line. There are a variety of supplier buildings surrounding the main building.

Mercedes, says Dr. Annette Winkler, who heads up smart, the producer of small cars with the lower-case first letter in its name, decided that for the new smart fortwo—and it literally is “for two,” as in the number of passengers that can be accommodated in it—they wanted to make it more suitable for the U.S. market.

Certainly, the fortwo is offered in an array of global markets, European and Asian, some 46 in all. But they wanted a vehicle that would resonate better in America.

Realize that the model they were replacing has a length of 106.1 in., a wheelbase of 73.5 in., a height of 60.7 in., and a width of 61.4 in.

So the new fortwo has a length of 105.91 in., a wheelbase of 73.74 in., a height of 61.02 in., and a width of 65.35 in.

Which is to say that essentially, they made the new car wider by 3.9 in., with the rest of the dimensional changes being nearly imperceptible.

This width modification is, according to Winkler, “decisive.”

Yes, this means more interior room for the passengers. But it also means that the wheels are set more widely apart part, and located at the corners of the vehicle, which has the consequence of there being larger wheelhouses, which allow greater wheel turning, which results in one of the most touted aspects of the fortwo, which is that it has a turning circle of 22.8 ft. (Putting the engine in the back down and low and having no storage in the front helps this compact footprint, too.)

Which means that when it comes to maneuverability in places like cities—and the car is positioned by Winkler and all of her colleagues as an “urban vehicle,” particularly for what they refer to as “smart cities,” which are places with high traffic density, narrow roads, little parking space inhabited by those with environmental consciousness, creativity and a pioneering spirit, places like Portland and San Francisco, Rome and Paris—the smart is superb. At least for the turning capability.

Dr. Winkler refers to the car as “the hardware.” That is, she sees it as being an element in a larger system, which also includes a software element, with the software facilitating a mobility system. So as there becomes more of a multi-modal environment, where people use cars fit for purpose rather than fit for essentially everything (i.e., how often do you see a five-passenger sedan—or SUV—being driven by one person?), an environment predicated on a network of, well, networked vehicles, then the fortwo may really come onto its own in a big(ger) way.

Although one might think that being a small car it is an economy car, which tends to mean something with discount features, Winkler says, “This car is about premium.” At the very least, realize that this is a Mercedes-Benz product (yes, smart is a Daimler company). Consequently, the level of materials in the vehicle is high; the engine and transmission are both well engineered. There is no evident thrifting.

To that end, Heiko Schmidt, department manager, Product Management, notes that on the previous generation smart, the wheels were held on with three lug nuts. For the new model they have gone to four. A small, but telling thing.

In fact, Winkler points out that had they made the car four-inches longer, they would have been able to save money because there would be the possibility of using parts that are used for other Mercedes cars. “With this size,” she says, “we have to create parts for the vehicle.”

But what’s interesting is that while they had to create specific parts for the vehicle, the vehicle itself was developed along with Renault.

Renault has a city car, the Twingo. Back in 2008, Renault was contemplating a new version of that car, which was originally launched in 1992. They were thinking about a rear-engine architecture, something that the smart has had.

Daimler and Renault have been collaborating together for several years, at least in the context of the Renault-Nissan Alliance and Daimler. It has been more visibly Nissan-centric, as in the Nissan engine plant in Decherd, Tennessee, producing engines for both Infinti Q50 and the Mercedes C-Class since June 2014 and an assembly plant in Aguascalientes, Mexico, being built for the two brands (Infiniti production will start in 2017, followed by Mercedes Benz production in 2018).

In 2010, the two organizations started working together . . . and in 2010, those Renault engineers started collaborating with people from Daimler on the development of what was to become the smart fortwo (and the four-passenger version, the forfour) and the Twingo. According to Winkler, this collaboration allowed them to spread the costs for engineering.

It is worth noting that Renault is building the Twingo in its plant in Novo Mesto, Slovenia, along with the forfour; the fortwo is built at the smart plant in Hambach, France. For the new vehicles, some €450-million was invested in Novo Mesto; €200-million in Hambach. Investments in Hambach included equipment for gas-metal-arc welding and soldering in addition to conventional spot welding. There had been 160 robots used in the plant; they’ve upped the number to 500. The vehicle build is predicated largely on modules, so there are supplier companies on site including Magna (for the tridon safety cell, doors and tailgate), Faurecia (body panels), ThyssenKrupp (rear axle drive module and front axle), and SAS Automotive Systems (cockpit).

The 89-hp, three-cylinder turbocharged engine that powers the fortwo was also a joint development between the two companies.

As cited earlier, the fortwo is a small car by any measure. And the development engineers actually developed a new measure for dealing with the vehicle. It is called the “body space index” (BSI). This is a measure of how efficiently space is used. It is a ration between the interior to exterior length. The interior length is measured from the accelerator pedal in its unapplied position horizontally back to the rear end. The fortwo achieves an index of 75%, which the company describes as being a “top rating for this criterion.”

BSI notwithstanding, the smart fortwo is clearly a car for the urban environment.