Tech Briefs
Lightweight seating technology

The Precept premiered at the NAIAS in January. The open mesh material for the seating surface replaced polyurethane foam, trim, and suspension components. Magna Seating Systems developed the lightweight seating system for GM's Precept concept.

The Livonia, MI-based Magna Seating Systems developed the lightweight seating system for GM's hybrid electric vehicle (HEV) five-passenger Precept concept vehicle that premiered at the NAIAS in January, providing an 11% mass reduction over the EV1's seating system. The seating system features a variety of advanced technologies that reduce mass and increase overall occupant safety.

Magna supplied GM with a highly styled package while also surpassing both FMVSS and GM testing standards for occupant safety that proved it ready for application in series production. The entire structure, including adjusters, has a mass of only 9.7 kg (21 lb), bettering GM's target for a 10-kg (22-lb) seat. This and other mass-reduction efforts contributed to the Precept achieving a fuel efficiency of 2.9 L/100 km (80 mpg).

In engineering and designing the Precept's seating system, Magna eliminated traditional components through the development of innovative attachment methods. Extruded aluminum and high-strength steel were used extensively to maintain the seats' lightweight and structural integrity. Manual adjusters provide 270 mm (10.6 in) of seat travel and dual recliners allow a full 60° of seat back adjustment. Both hardware systems are Magna innovations, with the recliner being introduced on a production vehicle in North America later this year. The high-back bucket seat provides back and head support with a full halo-style design. In addition, both inner and outer lap belts are attached to the seat structure to optimize access and comfort of the restraint system. An open mesh material was used for the seating surface, replacing conventional polyurethane foam, trim, and suspension components.

Structural elements of the seat were powder coated and intentionally left exposed to complement specialty leather and open mesh seating surfaces to achieve a "techno-elegant" styling theme. In addition to providing mass savings, the open mesh suspension trim material allows air to circulate freely through the interior, improving temperature control of the passenger compartment. The black polymeric mesh suspension used in the seats is a significant architectural design element that reinforces the styling theme employed throughout the Precept's interior space.

Jean L. Broge