A practical approach for cross-functional vehicle body weight optimization

The goal of optimization in vehicle design is often blurred by the myriads of requirements belonging to attributes that may not be quite related. If solutions are sought by optimizing attribute performance-related objectives separately starting with a common baseline design configuration as in a traditional design environment, it becomes an arduous task to integrate the potentially conflicting solutions into one satisfactory design. It may be thus more desirable to carry out a combined multi-disciplinary design optimization (MDO) with vehicle weight as an objective function and cross-functional attribute performance targets as constraints. For the particular case of vehicle body structure design, the initial design is likely to be arrived at taking into account styling, packaging and market-driven requirements. The problem with performing a combined cross-functional optimization is the time associated with running such CAE algorithms that can provide a single optimal solution for heterogeneous areas such as NVH and crash safety. In the present paper, a practical MDO methodology is suggested that can be applied to weight optimization of automotive body structures by specifying constraints on frequency and crash performance. Because of the reduced number of cases to be analyzed for crash safety in comparison with other MDO approaches, the present methodology can generate a single size-optimized solution without having to take recourse to empirical techniques such as response surface-based prediction of crash performance and associated successive response surface updating for convergence. An example of weight optimization of spaceframe-based BIW of an aluminum-intensive vehicle is given to illustrate the steps involved in the current optimization process.

VSDSS, research studies. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

BODY FOR PNEUMATIC VEHICLE

A pneumatic vehicle is provided with a first and second sub-assembly. The first sub-assembly has a chassis supporting an air tank. The second sub-assembly has part of the vehicle body and is bonded to the first-sub-assembly using a structural adhesive. Another pneumatic vehicle is provided with a first and second sub-assembly. The first sub-assembly has a chassis, air tank, part of the vehicle body, a pair of B-pillars, and a pair of rear rails. The second sub-assembly has a part of the vehicle body, a pair of A-pillars, and a pair of roof rails. A vehicle seat is provided with a seat base and upright seat back providing a seating area. A bladder located in the central region of the seating area inflates to provide two bucket seats, and deflates to provide a bench seat. The vehicle seat also has inflatable inserts to provide cushioning.

Body for pneumatic vehicle

A pneumatic vehicle is provided with a first and second sub-assembly. The first sub-assembly has a chassis supporting an air tank. The second sub-assembly has part of the vehicle body and is bonded to the first-sub-assembly using a structural adhesive. Another pneumatic vehicle is provided with a first and second sub-assembly. The first sub-assembly has a chassis, air tank, part of the vehicle body, a pair of B-pillars, and a pair of rear rails. The second sub-assembly has a part of the vehicle body, a pair of A-pillars, and a pair of roof rails. A vehicle seat is provided with a seat base and upright seat back providing a seating area. A bladder located in the central region of the seating area inflates to provide two bucket seats, and deflates to provide a bench seat. The vehicle seat also has inflatable inserts to provide cushioning.

Pneumatic vehicle

A pneumatic vehicle is provided with a first sub-assembly with a chassis, part of the vehicle body, a pair of B-pillars, a pair of rear rails, wheels, an elongate aluminum compressed load bearing air tank oriented longitudinally in the chassis, side panels connected to the tank and the wheels, a heat exchanger to heat the compressed air, and an air motor driven by the heated, compressed air and connected to a wheel. A ventilation system has a restrictive solenoid valve for directing air to the heat exchanger. The air tank is provided with a carbon filament reinforced plastic layer, and a fiberglass and aramid-fiber layer. A second sub-assembly includes part of the vehicle body bonded to the first-sub-assembly using a structural adhesive, a pair of A-pillars, and a pair of roof rails. Seating includes inflatable components for adjustment.

CHASSIS FOR PNEUMATIC VEHICLE

A pneumatic vehicle is provided with a first sub-assembly with a chassis, part of the vehicle body, a pair of B-pillars, a pair of rear rails, wheels, an elongate aluminum compressed load bearing air tank oriented longitudinally in the chassis, side panels connected to the tank and the wheels, a heat exchanger to heat the compressed air, and an air motor driven by the heated, compressed air and connected to a wheel. A ventilation system has a restrictive solenoid valve for directing air to the heat exchanger. The air tank is provided with a carbon filament reinforced plastic layer, and a fiberglass and aramid-fiber layer. A second sub-assembly includes part of the vehicle body bonded to the first-sub-assembly using a structural adhesive, a pair of A-pillars, and a pair of roof rails. Seating includes inflatable components for adjustment.

PNEUMATIC VEHICLE

A pneumatic vehicle is provided with a first sub- assembly with a chassis, part of the vehicle body, a pair of B-pillars, a pair of rear rails, wheels, an elongate aluminum compressed load bearing air tank oriented longitudinally in the chassis, side panels connected to the tank and the wheels, a heat exchanger to heat the compressed air, and an air motor driven by the heated, compressed air and connected to a wheel. A ventilation system has a restrictive solenoid valve for directing air to the heat exchanger. The air tank is provided with a carbon filament reinforced plastic layer, and a fiberglass and aramid-fiber layer. A second sub-assembly includes part of the vehicle body bonded to the first-sub-assembly using a structural adhesive, a pair of A-pillars, and a pair of roof rails. Seating includes inflatable components for adjustment.

Chassis for pneumatic vehicle

A pneumatic vehicle is provided with a first sub-assembly with a chassis, part of the vehicle body, a pair of B-pillars, a pair of rear rails, wheels, an elongate aluminum compressed load bearing air tank oriented longitudinally in the chassis, side panels connected to the tank and the wheels, a heat exchanger to heat the compressed air, and an air motor driven by the heated, compressed air and connected to a wheel. A ventilation system has a restrictive solenoid valve for directing air to the heat exchanger. The air tank is provided with a carbon filament reinforced plastic layer, and a fiberglass and aramid-fiber layer. A second sub-assembly includes part of the vehicle body bonded to the first-sub-assembly using a structural adhesive, a pair of A-pillars, and a pair of roof rails. Seating includes inflatable components for adjustment.

Chassis for pneumatic vehicle

A pneumatic vehicle is provided with a first sub-assembly with a chassis, part of the vehicle body, a pair of B-pillars, a pair of rear rails, wheels, an elongate aluminum compressed load bearing air tank oriented longitudinally in the chassis, side panels connected to the tank and the wheels, a heat exchanger to heat the compressed air, and an air motor driven by the heated, compressed air and connected to a wheel. A ventilation system has a restrictive solenoid valve for directing air to the heat exchanger. The air tank is provided with a carbon filament reinforced plastic layer, and a fiberglass and aramid-fiber layer. A second sub-assembly includes part of the vehicle body bonded to the first-sub-assembly using a structural adhesive, a pair of A-pillars, and a pair of roof rails. Seating includes inflatable components for adjustment.

Tri-level study: modification. Task 1: final report on potential benefits of various improvements in vehicle systems in preventing accidents or reducing their severity. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Oldsmobile Omega X-body baseline weight data. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Development of a motor vehicle materials historical, high volume industrial processing rates cost data bank (light truck). Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Body/repair shop visits to determine distribution of replacement parts sources. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Steel optimization and substitution for 1980 Oldsmobile Omega X-body car. Final report.

National Highway Traffic Safety Administration, Office of Research and Development, Washington, D.C.