Hop into the 2005 Ford Mustang and crank up the stereo. You're not just listening to classic rock or the latest hip-hop, you're hearing the sound of a plastics breakthrough.
The sports car marks the debut of an acoustic chamber and subwoofer designed as an integrated part of the injection molded substrate, molded and vibration welded into place in an automated process that decreases costs, reduces the sound system space requirements and improves the overall sound quality.
``This has been very interesting and a lot of fun to do,'' said Bob Stafford, product engineering supervisor for Visteon Corp., which developed and molds the system. ``This has been the best four years of my life.''
The integrated chamber also won Dearborn, Mich.-based Ford Motor Co. the Society of Plastics Engineers Automotive Division grand prize in its annual awards, presented Nov. 10 in Livonia, Mich.
The chamber was one of more than 50 products entered in the competition and also tied for the top notice in the body interior category.
The system grew from a combined Visteon and Ford research project to produce a door panel substrate that would include the entire door module, including the audio connections, window regulators, energy absorbers and other systems, Stafford said.
At that point, Visteon - which recently moved its headquarters to Van Buren Township, Mich., near Romulus — was considering a blow molded audio chamber that will replace the standard speaker setup. While the complete module did not make the cut, the team still liked the concept of the integrated audio unit.
As the development continued, though, Visteon turned from blow molding to injection molding to turn out the speaker.
``It was brand-new for all of us,'' Stafford said.
And it was not a simple move of swapping out an existing speaker system for a different material. The chamber must be hermetically sealed to ideally channel the sounds into the passenger compartment.
Visteon engineers had to design in a flange around every heat seal to retain the integrity of the hermetically sealed chamber, even while accommodating the placement of window regulators and other working systems inside the door, he said.
Visteon also had to find the right material blend as it considered the chamber's placement within the vehicle.
The unit took up space where the firm normally uses an expanded polypropylene or polyurethane foam for impact protection, Stafford noted. But the company found that by designing the unit to collapse during a collision, the chamber can double as impact protection, eliminating the need for EPP or foam.
To make it work, Visteon and material supplier Ferro Corp. had to come up with a PP that used 10 percent glass fill for structural stability to keep the chamber strong enough for daily wear and tear, but also a 12 percent rubber blend to allow it to collapse in a crash.
``Working with the customer, we were going back and forth trying to get it to work,'' he said.
It not only worked, it has outperformed standard acoustics and at a savings of more than $40 per vehicle.
The speaker system in the new Mustang, with only two subwoofers encased in Visteon's injection molded chambers, plays 8 decibels louder than its predecessor with four woofers. Being able to drop the two rear speaker units creates additional space in the trunk, and saves 18 pounds per vehicle.
The integrated woofers also provide better protection from the damage that can occur when parts shake apart from repeated door slams, he said.
Mustang drivers and passengers likely will never know about the audio switch. All they see on the door panel - also made by Visteon at its Utica, Mich., shop - is a standard speaker grille.
Even as its production continues for the 2005 Mustang, the auto supplier also is introducing the system for other vehicles with a variety of automakers.
``Why wouldn't we want to see this used in a truck, where you don't have a back seat or package tray to house those [rear] woofers?'' Stafford noted.
Other top award winners from the SPE event were:
* GÃ¶teborg, Sweden-based AB Volvo's 2005 S40 and V50 models, sharing the interior award with the Ford Mustang, for its use of an integrated cross car beam in the instrument panel carrier. Faurecia SA of Nanterre, France, molds the units, using a glass-mat thermoplastic from Quadrant AG in Zurich, Switzerland.
* Detroit-based General Motors Corp.'s full-size sport utility vehicles for the blow molded running boards produced by ABC Group Inc. of Toronto. The boards include an integrated step pad and were developed by ABC using a proprietary thermoplastic blend and molded on equipment specially developed by the firm.
* A new award was given this year, the Engineering Excellence Award, to Porsche AG of Stuttgart, Germany, for its 2005 Carrera GT, and specifically, its ground-breaking development of a carbon-fiber engine frame and ceramic matrix composite clutch plate.
The group has never before given an award for an entire vehicle, but in this case, SPE felt it was time to develop a stand-alone award for engineering excellence to a company that has gone over and beyond the norm, especially with regard to the use of plastics. Looking forward, SPE said it will keep this award for future vehicles that exemplify these types of breakthrough engineering advancements.