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US 10,144,446 B2Granted
Vehicle and method for controlling vehicle
AssigneeSubaru Corporation
InventorsYoshisada Anma, Takeshi Torii
Life of this patent
Estimating the term…
Abstract
An apparatus for controlling a vehicle includes a power steering adjuster that adjusts an amount of an assistance in a steering to be provided by a power steering in accordance with a change in a state quantity related to an ease of a steering, and a steering stability controller that controls a control amount to perform a driving force control on a wheel of a vehicle in accordance with the change in the state quantity.
Claims15
A vehicle comprising:
- a power steering;
- and
- a controller configured to:
- adjust an amount of an assistance in a steering to be provided by the power steering, wherein the amount of the assistance is adjusted in accordance with a change in a state quantity related to an ease of the steering, wherein the state quantity is frequency-related data related to a steering input by a driver of the vehicle;
- control a control amount of a driving force on a wheel of the vehicle in accordance with the change in the state quantity;
- calculate a target yaw rate of the vehicle based on a vehicle model that defines a relationship between the target yaw rate of the vehicle and a vehicle speed and a steering wheel angle with a target stability factor, wherein the target stability factor is a parameter, related to a turning performance of the vehicle, determined from specifications of the vehicle,
- wherein the target stability factor comprises a first stability factor, a second stability factor greater than the first stability factor, and a third stability factor calculated with linear interpolation between the first stability factor and the second stability factor;
- vary the turning performance of the vehicle by:
- when an absolute value of the frequency-related data is smaller than or equal to a first threshold value, setting the first stability factor as the target stability factor,
- when the absolute value of the frequency-related data is greater than or equal to a second threshold value, setting the second stability factor as the target stability factor, and
- when the absolute value of the frequency-related data is greater than the first threshold value and smaller than the second threshold value, setting the third stability factor as the target stability factor;
- compare the frequency-related data with a threshold value;
- determine whether the target stability factor should be corrected or not, based on a result of the comparison of the frequency-related data with the threshold value;
- correct the target stability factor based on the determination that the target stability factor should be corrected;
- and
- control the vehicle based on the target yaw rate.
13 more elements
A vehicle comprising:
- a power steering, and
- a controller configured to:
- adjust an amount of an assistance in a steering to be provided by the power steering, wherein the amount of the assistance is adjusted in accordance with a change in a state quantity related to an ease of the steering, wherein the state quantity is frequency-related data related to a steering input by a driver of the vehicle;
- control a control amount of a driving force on a wheel of the vehicle in accordance with the change in the state quantity;
- cause the amount of the assistance to decrease as high-frequency components included in the frequency-related data increase;
- calculate a reference value of a front wheel steering angle and a steering wheel torque based on a steering model;
- calculate the frequency-related data based on:
- a result of a frequency analysis of at least one of the steering wheel torque and an amount of a steering operation by the driver, or
- at least one of a change in a first rate of change in the steering wheel torque and a change in a second rate of change in the amount of the steering operation;
- calculate a steering correction gain for correcting the reference value of the front wheel steering angle based on the frequency-related data;
- multiply the reference value of the front wheel steering angle by the steering correction gain;
- calculate a requested value of the front wheel steering angle based on the multiplication of the reference value of the front wheel steering angle by the steering correction gain;
- and
- output the requested value of the front wheel steering angle to the power steering,
- wherein the controller is further configured to calculate the frequency-related data based on a ratio between a first area obtained by a first integration of a waveform resulting from the frequency analysis, and a second area obtained by a second integration of a portion of the waveform over a range greater than or equal to a predetermined frequency range.
12 more elements
A method for controlling a vehicle, the method comprising:
- adjusting an amount of an assistance in a steering to be provided by a power steering of the vehicle, wherein the amount of the assistance is adjusted in accordance with a change in a state quantity related to an ease of the steering, wherein the state quantity is frequency-related data related to a steering input by a driver of the vehicle;
- controlling a control amount of a driving force on a wheel of the vehicle in accordance with the change in the state quantity,
- wherein the controlling the control amount includes:
- calculating a target yaw rate of the vehicle based on a vehicle model that defines a relationship between the target yaw rate of the vehicle and a vehicle speed and a steering wheel angle with a target stability factor, wherein the target stability factor is a parameter, related to a turning performance of the vehicle, determined from specifications of the vehicle,
- wherein the target stability factor comprises a first stability factor, a second stability factor greater than the first stability factor, and a third stability factor calculated with linear interpolation between the first stability factor and the second stability factor;
- varying the turning performance of the vehicle by:
- when an absolute value of the frequency-related data is smaller than or equal to a first threshold value, setting the first stability factor as the target stability factor,
- when the absolute value of the frequency-related data is greater than or equal to a second threshold value, setting the second stability factor as the target stability factor, and
- when the absolute value of the frequency-related data is greater than the first threshold value and smaller than the second threshold value, setting the third stability factor as the target stability factor;
- comparing the frequency-related data with a threshold value;
- determining whether the target stability factor should be corrected or not, based on a result of the comparison of the frequency-related data with the threshold value;
- and
- correcting the target stability factor based on the determination that the target stability factor should be corrected;
- and
- controlling the vehicle based on the corrected target stability factor.
12 more elements
A method for controlling a vehicle, the method comprising:
- adjusting an amount of an assistance in a steering to be provided by a power steering of the vehicle, wherein the amount of the assistance is adjusted in accordance with a change in a state quantity related to an ease of the steering;
- controlling a control amount of a driving force on a wheel of the vehicle in accordance with the change in the state quantity,
- wherein the state quantity is frequency-related data related to a steering input by a driver of the vehicle,
- wherein, in the adjusting the amount of the assistance, the amount of the assistance is decreased as high-frequency components included in the frequency-related data increase, and
- wherein the adjusting the amount of the assistance includes:
- calculating a reference value of a front wheel steering angle and a steering wheel torque based on a steering model,
- calculating the frequency-related data based on:
- a frequency analysis of at least one of the steering wheel torque and an amount of a steering operation by the driver, or
- at least one of a change in a first rate of change in the steering wheel torque and a change in a second rate of change in the amount of the steering operation;
- calculating a steering correction gain for correcting the reference value of the front wheel steering angle based on the frequency-related data;
- multiplying the reference value of the front wheel steering angle by the steering correction gain;
- and
- calculating a requested value of the front wheel steering angle based on the multiplication of the reference value of the front wheel steering angle by the steering correction gain;
- and
- outputting the requested value of the front wheel steering angle to the power steering;
- and
- controlling the power steering of the vehicle based on the requested value of the front wheel steering angle,
- wherein the frequency-related data is further calculated based on a ratio between a first area obtained by a first integration of a waveform resulting from the frequency analysis, and a second area obtained by a second integration of a portion of the waveform over a range greater than or equal to a predetermined frequency range.
15 more elements
Dependencies are inferred from the claim text.