Jason D Kramer

US Patent:

6909951, Jun 21, 2005

Filed:

Sep 12, 2003

Appl. No.:

10/661996

Inventors:

David R. Llewellyn - West Bloomfield MI, US
William G. Spadafora - Clarkston MI, US
Jason G. Kramer - Sterling Heights MI, US

Assignee:

Dana Corporation - Ottawa Lake MI

International Classification:

B62D006/00

US Classification:

701 43, 180 78

Abstract:

A fail-safe torque transducer, and automotive power steering system, utilizing a two-stage series coupled torsion bar system. A first stage torsion bar provides tuning of the steering system, and by reducing its diameter relative to the second stage, provides a lower torsional spring rate and higher operational stress level than that of the second stage. The second stage torsion bar provides the stress/strain indicia referenced by a torque-measuring device, and is stressed at a lower level than the first stage and therefore has a higher cycle life than that of the first stage bar. Hence, if stress related failure ever occurs, it will only occur in the first stage torsion bar, thereby preventing any torque from reaching the second stage, thereby causing a zero strain signal and thus rendering the system fail-safe and not subject to instability of vehicle steering if the torsion bar breaks.

US Patent:

8234045, Jul 31, 2012

Filed:

Sep 24, 2008

Appl. No.:

12/236957

Inventors:

William Spadafora - Clarkston MI, US
David Llewellyn - West Bloomfield MI, US
Perry Paielli - Brighton MI, US
Jason Kramer - Macomb Township MI, US

Assignee:

Robert Bosch GmbH - Stuttgart

International Classification:

B62D 11/00
G05D 1/00
B60R 22/00
G06F 7/00
B60B 39/00
G08B 29/00

US Classification:

701 43, 701 1, 701 48, 701 53, 701 71, 340507

Abstract:

Systems and methods for mitigating failure mode effects in a steer-by-wire system. The system includes a controller configured to alter a direction of the vehicle when the controller is in a failure mode. A steering device is coupled to a detector. The detector is configured to detect a steering input from a driver and output a signal representative of the steering input. A first actuator is coupled to a first control device. The first control device is configured to generate a first control signal representative of the steering input when the controller is in the failure mode. The first actuator alters the direction of the vehicle by removing energy from the vehicle. A second actuator is coupled to a second control device. The second control device is configured to generate a second control signal representative of the steering input when the controller is in the failure mode. The second actuator alters the direction of the vehicle by adding energy to the vehicle.