Saturn's side-impact airbags
Head curtain airbags designed to decrease the severity of head and neck injuries in side-impact collisions are an option on Saturn's 2001 model year L-Series sedan and wagon and the S-Series sedan, wagon, and coupe. "While this new airbag technology was developed by our engineers for Saturn vehicles, it will eventually be shared among other General Motors brands," said Jim Ulrich, Vice President of Engineering for Saturn Corp.
Saturn's head curtain airbag system is stored along the vehicle's body side upper roof rail behind the headliner and garnish trim. The airbag deploys based on feedback from electronic sensors located along the sides of the vehicle. The airbag drops from the roof rail and unfolds as it inflates, providing a cushion to help protect the head and neck regions.
Side impacts are second only to frontal impacts as a source of injuries and fatalities to passenger car occupants. Side-impact crashes account for approximately 30% of crashes in small and mid-size cars. About half of the harm from serious injury in side-impact crashes is associated with head and neck injuries. Side-impact head curtain airbags are intended to work with seatbelts to help cushion the head and neck in many of these types of crashes and are expected to significantly reduce these injuries.
The head curtain airbags from Saturn are also engineered to minimize the risk of harm to out-of-position adults and children. To study the benefit of this technology in a laboratory test environment, Saturn vehicles were subjected to a variety of tests, including a 29-km/h (18-mph) side-impact test where a pole was aimed at a test dummy's head. Based on data from the side-pole-impact test, the addition of the head curtain airbag creates the potential to significantly reduce head injury.
Saturn also uses steel door beams in each door, cross-car underbody beams, a reinforced side-pillar structure, and energy absorbing door trim and foam padding to help provide protection for the occupant's chest, spine, and pelvis.
Jean L. Broge
Dana's magnetic-pulse welding
Dana Corp.'s Spicer Driveshaft and Structural Products divisions has developed and is implementing an improved magnetic-pulse process for joining ferrous and non-ferrous materials together to manufacture lighter, more compact, and previously nonmanufacturable driveshaft and structural components for light-duty vehicles. According to the company, the process is for use in bi-metallic applications such as engine cradles, full-perimeter frames, and spaceframes.
"We're utilizing an innovation usually applied to drive-shafts where it makes sense in other applications for our automotive customers," said Mike Greene, Vice President of Dana's Parish Structural Components Group.
The new magnetic-pulse process, which will be used on an as yet unnamed, near-future SUV produced by a domestic OEM, allows Dana to join steel and aluminum components to create a variety of driveshaft and structural designs. Steel components can withstand the high stresses associated with small diameters, and aluminum parts are lightweight and corrosion resistant. According to Jim Duggan, Chief Engineer of Advanced Design for Spicer Driveshaft Division, the resulting connection is a metallurgical attachment that outperforms conventional MIG welding and other mechanical attachment processes.
"We manufacture a variety of driveshafts that serve a diverse range of applications," said Duggan. "Each application has a driveshaft tailored to meet specific performance characteristics for that operating environment. Reliably joining different components to take advantage of each material's properties was difficult, and in some cases impossible. This Dana developed technology allows us to push the envelope on power transmission designs for passenger cars, light trucks, and sport utility vehicles."
The
process creates an intense magnetic field by downloading large amounts of electrical
energy into a specifically designed coil over a very short period of time. When
an aluminum tube is subjected to the magnetic field, it collapses inward with
sufficient force to weld itself onto a stationary component such as a steel
or aluminum tube yoke or hydroformed tube. This process is a solid-state weld.
No heat is used, and the component orientation is controlled by the machine
tooling.
Dana's new magnetic-pulse process allows the
company to join steel and aluminum components
in a variety of driveshaft or structural applications.
Variations of magnetic-pulse welding and magnetic-pulse forming were described over 60 years ago. Those processes have been used for attaching small diameter capillary tubes for refrigeration applications and to seal the end of fuel rods for the nuclear industry.
Dana's machine design and assembly work was no simple accomplishment because the process can require more than one million amps and up to 5000 V of electricity. "Manufacturing Technology, Inc., of South Bend, IN, has been our developmental partner since this project began five years ago," said Duggan. "The company's expertise in friction/inertia welding and production equipment has made this program a success."
Jean L. Broge
Tire-tread measurement sensor
A new high-speed profiling sensor system from LMI Selcom enables tire manufacturers to measure parameters such as thickness, width, and profile for on- and off-line quality control. The 2301 sweeping beam sensor is a flexible and compact, noncontact, industrial, laser-based profile sensor with an oscillating mirror that rapidly sweeps laser light across the surface of extruded rubber or other materials.
With a frequency of up to 30 Hz and a +/-30° measurement angle, the sensor
achieves up to 60 profiles/second for quality control and monitoring of the
production process. The 2301 is available as a complete measuring system featuring
industry-standard
programmable software from Bytewise Measurement Systems. According to LMI Selcom,
the software saves OEMs, systems integrators, and other users the time and energy
usually spent searching for and building their own systems.
The high-speed, sweeping-beam laser
profiling system from LMI Selcom
enables tire manufacturers to measure
thickness, width, and profile.
Applications for the sensor system include tracking the position of surface features such as ridges, center lines, or edges in an extrusion process. The sensor is also useful for detecting tire profile center lines and for feature tracking of tread extrusions, edge tracking, gap measurement, lateral runout measurement, continuous groove depth measurement, strip placement monitoring, glue bead volume measurement, and other related applications.
The position sensitive detector (PSD) technology used in the 2301 is digitally calibrated to 4000 discrete linear points within the measurement range, making single-point or dual-head thickness measurement simple. According to LMI Selcom, unlike various other sensors, green rubber, lubrication oil, white sidewalls, high-silicon content, or lettering will not cause invalid readings.
Jean L. Broge
