'Hybrid' instrument panel cuts cost, weight of Cougar

Flat Rock, MI--The new Mercury Cougar's "hybrid" instrument panel (IP) eliminates 10 parts, reduces weight by four lb (1.8 kg), and cuts the cost of a traditional IP design. The global teamwork project involved Ford, Visteon Automotive Systems, Textron Automotive, and Dow Automotive.

The hybrid IP combines a traditional steel structural beam with a retainer made from PULSE(TM) PC/ABS resin supplied by Dow Plastics (Midland, MI). The design takes advantage of the energy-management properties of the material to help the Cougar meet North American and European standards for occupant safety, while satisfying performance targets.

"From the start, we knew we needed to work within certain parameters of Mercury's traditional IP architecture, which included the steel cross-car beam," notes Rick Lee, interior market manager for Dow Automotive. "Although we have been involved with both traditional IPs and structural plastic IPs, we understood that a 'one-size-fits-all' approach doesn't work. Our goal was to deliver a solution for the Cougar that best met our customer's needs."

Mercury wanted to maintain the steel cross-car beam to take advantage of capital investments in place for the Mondeo, Contour, and Mystique. These models are based on the same platform as the new Cougar, made by Auto Alliance International.

Visteon (Dearborn, MI) asked Textron Automotive (Troy, MI) and Dow Automotive (Southfield, MI) to suggest ideas to reduce cost and weight, while still using the steel beam. "Textron and Dow proposed a hybrid IP system, using a ductile thermoplastic to complement the steel beam," Lee recalls. "The idea was to reduce the number of steel components in the IP system, and use plastic to do more energy management work. This steel optimization saved weight and cost and convinced Mercury to give the go-ahead on the design."

Ford's global small-car engineering takes place in Europe. Therefore, Dow Automotive co-located engineers in the U.K. and Germany to work with Mercury and Textron Automotive during the critical development phase. Bringing the development work together enabled Visteon to expedite the design process immediately.

In addition, Dow Automotive engineers residing in Europe had direct computer links with company resources in Southfield and Midland. This permitted the program to move ahead virtually on a 24-hour-a-day basis.

The new design eliminated seven steel brackets from the cross-car structure, with PULSE PC/ABS resin replacing the metal-reinforced knee bolster. CAD allowed the team to analyze the design in terms of meeting crashworthiness standards, as well as performance requirements for noise, vibration, and harshness.

"We couldn't have done this redesign with a glass-filled material," says Lee. "When you reduce the use of steel, the material may fracture rather than absorb energy during impact." Switching from a brittle plastic to PC/ABS, a ductile material, gave the team the latitude to re-engineer the system to eliminate some of the steel.

One of the team's challenges involved working with the IP system's "fish eye" rotating air registers. Computer modeling enabled the team to keep the style element, while still meeting head-impact standards.

"This provides a good example of how a systems approach ultimately saves costs," Lee concludes. "With a system approach, the OEM, the Tier One integrator, and the material supplier contribute their expertise to find the best solution."

Based on this experience, Visteon has selected PULSE 2000 PC/ABS resin, a new global grade, to replace polycarbonate on IPs and other interior applications on Ford trucks.