Traditionally, consumers have limited choices available when it comes to specifying interiors. For instance, most vehicles are equipped with either leather or cloth fabric seats. Instrument panels, floor consoles, headliners, door panels and trim typically come in beige, black, gray or white.

But, those limitations may soon be a thing of the past, because drivers increasingly want personalized vehicles. Automakers and suppliers hope to address this demand with a wide choice of optional equipment.

“The next big trend will be the ability to customize and reconfigure interiors to fit individual tastes,” notes Dave Cole, chairman of the Center for Automotive Research (CAR, Ann Arbor, MI). “Customization is going mainstream. The ability to tailor a vehicle to individual tastes is changing.”

Cole says onboard electronics are a good example of this trend. Indeed, there has been a sharp increase in electronic integration with traditional trim pieces in recent years.

Cole also believes the annual Specialty Equipment Market Association (SEMA) show in Las Vegas is serves as a strong catalyst behind the trend. Every fall, the huge event attracts OEMs and suppliers eager to showcase the latest solutions for personalizing vehicles.

More and more automakers and suppliers are focusing on modularization to offer consumers more unique, personalized interiors. “Assembly of seating systems, overhead modules and cockpit modules as single bolt-on units simplifies the production process by reducing the number of parts involved and cutting back on engineering costs,” explains Amit Goel, a research analyst at Frost & Sullivan Inc. (San Antonio).

A cockpit module typically includes an instrument panel and one or more of the following: wire harness, audio, instrument cluster, climate control head, finish panels, steering column and steering wheel. Cockpit modules typically contain as many as 63 components from as many as 15 different suppliers.

Paul Hoelterman, director of global market assessment at CSM Worldwide (Northville, MI), says modularization will transform automotive interiors. According to Hoelterman, Toyota Motor Corp. (Nagoya, Japan) is currently in the midst of a major cockpit modularization initiative.

“Toyota is enhancing modules for interior applications,” explains Hoelterman. “The goal is to use one part that used to [require] five parts before. We’ll probably see this strategy applied to 2009 or 2010 model-year vehicles.”

Engineers at Siemens VDO Automotive AG (Regensburg, Germany) have also developed a modular cockpit, which they call CESAR [Cockpit Electro-Mechanical System Architecture]. In contrast to conventional cockpits, it provides a platform for a wide variety of cockpit models at a much higher quality level, making it possible to respond with ever greater flexibility to individual requirements and market changes.

Normally, cockpit modules are developed from scratch for each vehicle model. Individual assemblies, such as steering wheels, climate control systems, entertainment systems, ducting and electronics, are grouped together into an overall system.

With CESAR, Siemens VDO engineers are exploring a more system-oriented approach by redesigning the cockpit development process. The system as a whole, rather than the individual components, is now the initial point of departure. This means thinking in holistic terms and abandoning the perception that individual parts, such as the radio, instrument cluster or climate control unit, need to be developed separately and then assembled into the cockpit in its final stage.

Compared to conventional cockpits, it lowers costs by roughly 30 percent at higher quality standards, partly due to shorter development times. The concept also reduces weight by approximately 15 percent. This creates room for other tailored cockpit solutions or innovative components, such as head-up displays.

Modular construction allows considerable flexibility in interior design. The driver module, central and front passenger module are completely separate from each other and can be connected mechanically with a few fastening points and electronically by means of standardized interfaces.

The modules can be manufactured separately and are easily interchangeable on a plug-and-play basis. This concept facilitates smooth, problem-free technical and design modifications or the upgrading of individual functions, either during series production or later in the aftermarket. Also, the vehicle can be tailored to a customer’s specific requirements.

The mechanical backbone of CESAR is a die-cast magnesium cross-car beam. This cross-car beam houses connectors for the electrical connections and the attachments for mounting the individual modules. It also features a special recess for the wiring harness.

The modular construction also enables improvement of the production process. Fewer components and electrical connections reduce the number of assembly stations. Furthermore, the integration of the electronic systems allows a permanent testing of functions during assembly.