Abstract: The invention relates to a method for compensating for drive influences of a drive train of a motor vehicle on its steering system, said motor vehicle having an electric power steering system. A drive train simulation model which is integrated into the motor vehicle and permanently activated is used to determine disturbance variables from a driven behavior so that a compensation torque which counteracts the disturbance variables is generated for the power steering system.

Abstract: The invention relates to a method for compensating for drive influences of a drive train of a motor vehicle on its steering system, said motor vehicle having an electric power steering system. A drive train simulation model which is integrated into the motor vehicle and permanently activated is used to determine disturbance variables from a driven behavior so that a compensation torque which counteracts the disturbance variables is generated for the power steering system.

Abstract: A steering system (10) and method (70) for controlling the steering of a vehicle having a steering assembly including a steering wheel (12), a steering column (14) connected to said steering wheel (12), and an electric motor (20) operatively engaged with the steering assembly for supplying torque assist. A steering angle sensor (32) is employed for sensing an angular position ?c of the steering column (14). The steering system has first and second H-infinity controllers (64A and 64B) coupled in a feedback path (44) for generating first and second feedback signals as a function of the driver torque and first and second characteristics (JC and KC) of the steering system. One of the first and second feedback signals is selected and the selected feedback signal is combined with a feedforward signal to generate a motor control signal (U) as a function of the estimated torque.

Abstract: A steering system (10) and method (70) for controlling the steering of a vehicle having a steering assembly including a steering wheel (12), a steering column (14) connected to said steering wheel (12), and an electric motor (20) operatively engaged with the steering assembly for supplying torque assist. A steering angle sensor (32) is employed for sensing an angular position &thgr;c of the steering column (14). The steering system has first and second H-infinity controllers (64A and 64B) coupled in a feedback path (44) for generating first and second feedback signals as a function of the driver torque and first and second characteristics (JC and KC) of the steering system. One of the first and second feedback signals is selected and the selected feedback signal is combined with a feedforward signal to generate a motor control signal (U) as a function of the estimated torque.

Abstract: A steering system (10) and method (70) for controlling the steering of a vehicle having a steering assembly including a steering wheel (12), a steering column (14) connected to said steering wheel (12), and an electric motor (20) operatively engaged with the steering assembly for supplying torque assist. A steering angle sensor (32) is employed for sensing an angular position &thgr;c of the steering column (14). The steering system has first and second H-infinity controllers (64A and 64B) coupled in a feedback path (44) for generating first and second feedback signals as a function of the driver torque and first and second characteristics (JC and KC) of the steering system. One of the first and second feedback signals is selected and the selected feedback signal is combined with a feedforward signal to generate a motor control signal (U) as a function of the estimated torque.

Abstract: A steering system (10) and method (70) for controlling the steering of a vehicle having a steering assembly including a steering wheel (12), a steering column (14) connected to said steering wheel (12), and an electric motor (20) operatively engaged with the steering assembly for supplying torque assist. A steering angle sensor (32) is employed for sensing an angular position &thgr;c of the steering column (14). The steering system has first and second H-infinity controllers (64A and 64B) coupled in a feedback path (44) for generating first and second feedback signals as a function of the driver torque and first and second characteristics (JC and KC) of the steering system. One of the first and second feedback signals is selected and the selected feedback signal is combined with a feedforward signal to generate a motor control signal (U) as a function of the estimated torque.

Abstract: A steering system (10) and method (70) for controlling the steering of a vehicle having a steering wheel (12), a steering column (14)connected to the steering wheel (12), and an electric motor (20) operatively engaged with the steering column (14) for supplying torque assist. A velocity detector is employed for detecting an angular velocity {dot over (&thgr;)}m of the electric motor (20). The system has a torque estimator (40) for determining an estimated torque signal Tdest as a function of the detected motor velocity {dot over (&thgr;)}m, and a motor controller (30) for generating a motor control signal (U) as a function of the estimated torque. Accordingly, the present invention reduces the complexity and cost of the electric power assist steering system by eliminating the need for a conventional pinion torque sensor, without sacrificing vehicle steering performance.

Abstract: A steering system (10) and method (70) for controlling the steering of a vehicle having a steering wheel (12), a steering column (14) connected to said steering wheel (12), and an electric motor (20) operatively engaged with the steering column (14) for supplying torque assist. A steering angle sensor (32) is employed for sensing an angular position &thgr;c of the steering wheel (12). The system has a torque estimator (40) for determining an estimated torque signal (Tdest) as a function of the measured steering wheel angle, and a motor controller (30) for generating a motor control signal (U) as a function of said estimated torque. Accordingly, the present invention reduces the complexity and cost of the electric power assist steering system by eliminating the need for a conventional pinion torque sensor, without sacrificing vehicle steering performance.

Abstract: A steering system (10) and method (70) for controlling the steering of a vehicle having a steering assembly including a steering wheel (12), a steering column (14) connected to said steering wheel (12), and an electric motor (20) operatively engaged with the steering assembly for supplying torque assist. A steering angle sensor (32) is employed for sensing an angular position &thgr;c of the steering column (14). The system has a torque estimator (40) for determining an estimated torque signal (Tdest), and an H-infinity controller (64) coupled in a feedback path (44) for generating a feedback signal which is combined with a feedforward signal to generate a motor control signal (U) as a function of the estimated torque. Accordingly, the present invention provides a stable and robust control system, without sacrificing steering performance and desired steering feel.

Abstract: A method and system for controlling an automotive vehicle spindle-coupled road simulator with a predetermined effective road profile for a road surface uses tire loss-of-contact compensation to modify the tracking parameter in a control loop to avoid incorrectly loading a test vehicle. Tire deflection obtained during measurement of a vehicle's tire profile calculation is used to detect and flag regions where the tire profile is not a function of the road input so that the tire profile motion is governed only by the free dynamic response of the suspension. A tire model is first developed for a vehicle. The vehicle is then coupled to the spindle-coupled simulator, and a set of control signals is generated in a control loop. The control signals are used for driving the spindle-coupled simulator with the vehicle attached thereto so that a response generated by the simulator is consistent with the predetermined effective tire profile.

Abstract: A method for developing a tire model for use with an effective road profile in testing an automotive vehicle on a spindle-coupled road simulator defines a flat surface road plane in a three coordinate reference system to represent the effective road profile with the three coordinates comprising a plane vertical deflection, a plane radial contact angle, and a plane lateral contact angle. The tire is then excited over a predetermined range while on a tire test apparatus for developing the tire model. The tire test apparatus includes a flat tire contact plane moveable so as to contact the tire, the flat tire contact plane defining a three coordinate reference system to represent the effective road profile in the three coordinates.

Abstract: A method for developing a tire model for use with an effective road profile in testing an automotive vehicle on a spindle-coupled road simulator defines a flat surface road plane in a three coordinate reference system to represent the effective road profile with the three coordinates comprising a plane vertical deflection, a plane radial contact angle, and a plane lateral contact angle. The tire is then excited over a predetermined range while on a tire test apparatus for developing the tire model. The tire test apparatus includes a flat tire contact plane moveable so as to contact the tire, the flat tire contact plane defining a three coordinate reference system to represent the effective road profile in the three coordinates.

Abstract: A method for testing an automotive vehicle on a vehicle spindle-coupled simulator comprises the steps of driving a first vehicle over a test road surface, collecting spindle dynamics data from at least one spindle of said first vehicle, developing a first tire model for the first vehicle, estimating a road profile for the road surface based upon the spindle dynamics data and the first tire model, developing a second tire model for a second vehicle, coupling the second vehicle to the spindle-coupled simulator, and generating a set of control signals for driving the spindle-coupled simulator with the second vehicle coupled thereto so that a road response generated by the spindle-coupled simulator is consistent with the road profile. The method allows accurate testing of the second vehicle without driving it over the test road. The tire model is developed using system identification techniques.