摘要:
A brake system control for use in a vehicle with wheels, wheel brakes and a body, comprising the steps of: measuring a plurality of vehicle parameters; responsive to the measured parameters, determining at least a vehicle yaw rate, a vehicle slip angle, a desired yaw rate and a desired slip angle; responsive to the measured parameters, estimating a coefficient of adhesion between the vehicle wheels and a road surface; implementing a control responsive to the vehicle yaw rate and the desired yaw rate with a first authority and responsive to the vehicle slip angle and the desired slip angle with a second authority, wherein the first authority increases as the estimated coefficient of adhesion increases and decreases as the estimated coefficient of adhesion decreases; and controlling the wheel brakes responsive to the control to reduce a first difference between the vehicle yaw rate and the desired yaw rate and to reduce a second difference between the vehicle slip angle and the desired slip angle.
摘要:
A method and apparatus for determining likelihood of rollover of a vehicle and/or mitigating rollover of the vehicle is responsive to measured vehicle lateral acceleration and a measured one of vehicle roll rate and vehicle suspension displacements to derive estimates of roll angle and roll rate. First, preliminary, estimates of roll angle and roll rate are derived and used as pseudo-measurements in a dynamic, closed loop observer equation which represents a model of the vehicle in a first roll mode for roll angles small compared to a reference value indicating two wheel lift-off and a second roll mode for roll angles at least near a reference value indicating two wheel lift-off. The observer equation has parameters and gains with values for each mode stored as a function of roll angle index derived from measurements and pseudo-measured values. The observer equation produces second, improved values or roll angle and roll rate together indicating the likelihood of vehicle rollover. Rollover mitigating controls for brakes, active front steer, and/or active rear steer are also disclosed.
摘要:
A method and apparatus for determining likelihood of rollover of a vehicle and/or mitigating rollover of the vehicle is responsive to measured vehicle lateral acceleration and a measured one of vehicle roll rate and vehicle suspension displacements to derive estimates of roll angle and roll rate. First, preliminary, estimates of roll angle and roll rate are derived and used as pseudo-measurements in a dynamic, closed loop observer equation which represents a model of the vehicle in a first roll mode for roll angles small compared to a reference value indicating two wheel lift-off and a second roll mode for roll angles at least near a reference value indicating two wheel lift-off. The observer equation has parameters and gains with values for each mode stored as a function of roll angle index derived from measurements and pseudo-measured values. The observer equation produces second, improved values or roll angle and roll rate together indicating the likelihood of vehicle rollover. Rollover mitigating controls for brakes, active front steer, and/or active rear steer are also disclosed.
摘要:
An improved active brake control method which compensates for the effects of a banked road surface under both steady state and transient operating conditions of the vehicle. The control includes an observer for estimating the lateral velocity of the vehicle as a means of determining vehicle slip angle, and a time derivative of the estimated lateral velocity is used along with measured values of lateral acceleration, vehicle speed and yaw rate to compute the lateral acceleration component due to the banked road surface, referred to as the bank acceleration. The bank acceleration, in turn, is then used to correct the values of measured steering angle and the measured lateral acceleration used (1) to develop the desired yaw rate, slip angle and lateral acceleration, and (2) to estimate the surface coefficient of adhesion and slip angle. Partial compensation can be achieved by applying suitable gain factors to the computed bank acceleration, if desired.
摘要:
A hydraulic mount apparatus (20) for supporting a vibration source is disclosed. The mount apparatus (20) includes a housing (22) that defines a housing chamber (24) separated by a partition assembly (62) into a pumping chamber (64) and a receiving chamber (66), each containing a magnetorheological fluid (68). A flexible body (48) is partially disposed in the pumping chamber (64) for deforming elastically in response to vibrations caused by an external excitation. A fluid passage (106) extends between the pumping chamber (64) and the receiving chamber (66) for passing the fluid therebetween during low frequency vibrations. A piezostack actuator (118) partially extends into the pumping chamber (64) for moving within the pumping chamber (64) for varying the volume of the pumping chamber (64) to prevent a pressure increase in the pressure chamber to substantially cancel relatively high frequency vibrations.
摘要:
A hydraulic mount apparatus (20) for supporting a vibration source is disclosed. The mount apparatus (20) includes a housing (22) that defines a housing chamber (24) separated by a partition assembly (62) into a pumping chamber (64) and a receiving chamber (66), each containing a magnetorheological fluid (68). A flexible body (48) is partially disposed in the pumping chamber (64) for deforming elastically in response to vibrations caused by an external excitation. A fluid passage (106) extends between the pumping chamber (64) and the receiving chamber (66) for passing the fluid therebetween during low frequency vibrations. A piezostack actuator (118) partially extends into the pumping chamber (64) for moving within the pumping chamber (64) for varying the volume of the pumping chamber (64) to prevent a pressure increase in the pressure chamber to substantially cancel relatively high frequency vibrations.
摘要:
A tie bar assembly includes front and rear units each including inner inserts interconnected with outer inserts with webs of elastomeric material. A pole sub-assembly is disposed between the units. The pole sub-assembly and the units define front and rear fluid chambers containing a magneto-rheological fluid. Fluid orifices are disposed through the pole sub-assembly for flow of the magneto-rheological fluid between fluid chambers. An electromagnet coil generates an electromagnetic field to affect viscosity of the magneto-rheological fluid. A connecting rod connects inner inserts and is slidably disposed through the pole sub-assembly for causing movement of the magneto-rheological fluid between fluid chambers. A displacement sensor detects movement to generate a signal to the electromagnet coil. Front and rear travel cushions are each disposed on the inner inserts for limiting the movement of the inner inserts toward the pole sub-assembly.
摘要:
A magnetorheological fluid-based hydraulic mount apparatus (20, 220) for supporting a vibration source on a base is disclosed. A main fluid passage (104, 304) extends between pumping chamber (64, 264) and receiving chamber (66, 266) for passing the fluid therebetween. Electromagnet coil (98, 298) variably generates a magnetic flux across the main fluid passage to variably change the damping stiffness of the mount. A rate dip track passage (120, 320) extends between the pumping chamber (64, 264) and receiving chamber (66, 266) for oscillating the magnetorheological fluid (68, 268) therethrough to decrease the dynamic stiffness of the mount apparatus (20, 220) at predetermined frequencies. A controller (108) applies a current through the electromagnet coils (98, 298) at the predetermined frequencies and frequencies relatively close to and above the redetermined frequencies for substantially preventing the magnetorheological fluid (68, 268) from flowing through the main fluid passage (104, 304) to force the magnetorheological fluid (68, 268) to flow substantially only through the rate dip track passage (120, 320) for preventing a sharp increase in the dynamic stiffness of the hydraulic mount apparatus (20, 220) from occurring at these frequencies.
摘要:
A magnetorheological fluid-based hydraulic mount apparatus (20, 220) for supporting a vibration source on a base is disclosed. A main fluid passage (104, 304) extends between pumping chamber (64, 264) and receiving chamber (66, 266) for passing the fluid therebetween. Electromagnet coil (98, 298) variably generates a magnetic flux across the main fluid passage to variably change the damping stiffness of the mount. A rate dip track passage (120, 320) extends between the pumping chamber (64, 264) and receiving chamber (66, 266) for oscillating the magnetorheological fluid (68, 268) therethrough to decrease the dynamic stiffness of the mount apparatus (20, 220) at predetermined frequencies. A controller (108) applies a current through the electromagnet coils (98, 298) at the predetermined frequencies and frequencies relatively close to and above the redetermined frequencies for substantially preventing the magnetorheological fluid (68, 268) from flowing through the main fluid passage (104, 304) to force the magnetorheological fluid (68, 268) to flow substantially only through the rate dip track passage (120, 320) for preventing a sharp increase in the dynamic stiffness of the hydraulic mount apparatus (20, 220) from occurring at these frequencies.
摘要:
A tie bar assembly includes front and rear units each including inner inserts interconnected with outer inserts with webs of elastomeric material. A pole sub-assembly is disposed between the units. The pole sub-assembly and the units define front and rear fluid chambers containing a magneto-rheological fluid. Fluid orifices are disposed through the pole sub-assembly for flow of the magneto-rheological fluid between fluid chambers. An electromagnet coil generates an electromagnetic field to affect viscosity of the magneto-rheological fluid. A connecting rod connects inner inserts and is slidably disposed through the pole sub-assembly for causing movement of the magneto-rheological fluid between fluid chambers. A displacement sensor detects movement to generate a signal to the electromagnet coil. Front and rear travel cushions are each disposed on the inner inserts for limiting the movement of the inner inserts toward the pole sub-assembly.