Controlling lateral dynamics of vehicle

Abstract

A vehicle includes a suspension including a damper. The dampers are controlled by a control system that receives two or more input signals associated with a roll of a body of the vehicle and normalizes the two or more input signals to obtain two or more normalized signals. The two or more normalized signals are combined, and the combined signal and a speed of the vehicle are used to calculate a common damping force. The common damping force is used to calculate, for each wheel of a plurality of wheels of the vehicle, a damping force corresponding to each wheel. Then, operation of a damper for the wheel is commanded in accordance with the damping force corresponding to the wheel. The two or more input signals associated with the roll of the vehicle body may include a steering rate, a lateral acceleration, a lateral jerk, and a yaw rate.

Description

[0001] introduction

[0002] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 682,747, filed on August 13, 2024, entitled “CONTROLLING LATERAL DYNAMICS OF AVEHICLE”. Background Technology

[0003] This disclosure relates to the control of the lateral dynamics of a vehicle. Summary of the Invention

[0004] In one aspect, a control system used in a vehicle is configured to receive two or more input signals related to the vehicle's body roll, combine the two or more input signals to obtain a combined signal, and calculate a common damping force based on the combined signal and the vehicle's speed. The control system processes the common damping force to calculate a damping force corresponding to each of the vehicle's multiple wheels. The control system is configured to command the operation of a vehicle damper corresponding to each of the vehicle's multiple wheels based on the damping force corresponding to each wheel.

[0005] On the other hand, a vehicle includes a chassis, a plurality of wheels, and a plurality of suspensions connecting the wheels to the chassis, each of the plurality of suspensions including a damper. The vehicle includes a control system configured to receive two or more input signals related to vehicle body roll, normalize the two or more input signals to obtain two or more normalized signals, and combine the two or more normalized signals to obtain a combined signal. The control system calculates a common damping force based on the combined signal and the vehicle's speed. The control system processes the common damping force to calculate a damping force corresponding to each of the vehicle's plurality of wheels. The control system commands the operation of the vehicle's dampers corresponding to each of the vehicle's plurality of wheels based on the damping force corresponding to each wheel.

[0006] In another aspect, a damper control method includes: receiving two or more input signals related to vehicle body roll by a vehicle's control system; and normalizing the two or more input signals by the control system to obtain two or more normalized signals. The control system combines the two or more normalized signals to obtain a combined signal, and calculates a common damping force based on the combined signal and the vehicle's speed. The control system processes the common damping force to calculate a damping force corresponding to each of the vehicle's multiple wheels. The control system commands the operation of the vehicle's dampers corresponding to each of the vehicle's multiple wheels based on the damping force corresponding to each wheel. Attached Figure Description

[0007] Figure 1A Example vehicles that can be operated according to certain implementation schemes are illustrated.

[0008] Figure 1B An example is shown of a vehicle chassis having multiple operable drive units according to certain embodiments.

[0009] Figure 2 It is a schematic block diagram of components used to operate a vehicle according to certain implementation schemes.

[0010] Figure 3A It is a schematic block diagram that defines the forces and directions related to the dynamics of a vehicle.

[0011] Figure 3B This is a schematic diagram illustrating the suspension of a vehicle.

[0012] Figure 4 This is a schematic block diagram of a method for controlling a damper for a vehicle according to an embodiment of the present invention.

[0013] Figure 5A and Figure 5B This is a graph of the input signal related to vehicle body roll according to an embodiment of the present invention. Detailed Implementation

[0014] Vehicle suspension includes springs (e.g., coil springs, leaf springs, or air springs) to absorb shocks to the vehicle's wheels, thereby promoting stable vehicle handling and increasing passenger comfort. The suspension also includes dampers to limit movement of the vehicle chassis relative to the wheels. Specifically, dampers can be used to limit body roll (rotation about the vehicle's longitudinal axis). In the method described herein, the force applied by the damper is controlled by a valve that controls the flow of hydraulic fluid in response to movement of the wheels relative to the vehicle chassis. The force applied by the damper is determined based on the driving mode, vehicle speed, and values ​​related to body roll, such as lateral acceleration, steering rate, lateral jerk (the rate of change of lateral acceleration), and yaw rate.

[0015] The adjustment of damper operation is simplified and implemented by normalizing and combining signals related to vehicle roll into a single signal, which is then used to obtain a common damping force value based on other variables such as vehicle speed and driving mode. The common damping force is further processed directly to determine the damping force to be generated at each damper. This method reduces the number of adjustable parameters while still considering multiple signals related to vehicle roll. Therefore, the adjustment of the vehicle suspension is simplified while still achieving the desired vehicle dynamics.

[0016] Figure 1AAn example vehicle 100 in which the methods described herein can be implemented is shown. Figure 1A As shown, vehicle 100 has multiple external cameras 102 and one or more front displays 104. Each of these external cameras 102 can capture a specific view or perspective of the exterior of vehicle 100. The images or videos captured by the external cameras 102 can then be displayed on one or more displays in vehicle 100, such as one or more front displays 104, for the driver to view.

[0017] refer to Figure 1B The vehicle 100 may include a chassis 106, which includes a frame 108 that provides the main structural components of the vehicle 100. The frame 108 may be formed by one or more beams or other structural components, or may be integral with the vehicle body (e.g., a monolithic construction).

[0018] In embodiments where vehicle 100 is a battery electric vehicle (BEV) or possibly a hybrid vehicle, a large battery 110 is mounted to the chassis 106 and may occupy a significant portion (e.g., at least 80%) of the area within the frame 108. For example, battery 110 may store 100 to 200 kWh. Battery 110 may be a lithium-ion battery or other types of rechargeable battery. The battery may be substantially planar in shape.

[0019] Power from battery 110 can be supplied to one or more drive units 112. Each drive unit 112 may consist of an electric motor and possibly a gear train providing gear reduction. In some embodiments, a single drive unit 112 drives either the front or rear wheels of vehicle 100. In another embodiment, two drive units 112 are present, each driving either the front or rear wheels of vehicle 100. In yet another embodiment, four drive units 112 are present, each driving one of the four wheels of vehicle 100.

[0020] Power from the battery 110 can be supplied to the drive unit 112 via one or more power modules 114 (such as power modules for each drive unit 112 or a pair of drive units 112). The power modules 114 may include inverters configured to convert direct current (DC) from the battery 110 into alternating current (AC) supplied to the motor of the drive unit 112. The power modules 114 also facilitate the operation of the motor of the drive unit as a generator to provide regenerative braking. The power modules 114 further facilitate the transfer of regenerative current to the battery 110.

[0021] A drive unit 112 is coupled to two or more wheel hubs 116 to which wheels can be mounted. Each wheel hub 116 includes a corresponding brake 118, such as a disc brake as illustrated. Each wheel hub 116 is further coupled to a frame 108 via a suspension 120. The suspension 120 may include metal or pneumatic springs for absorbing shocks. The suspension 120 may be implemented as a pneumatic or hydraulic suspension capable of adjusting the ground clearance of the chassis 106 relative to a supporting surface. The suspension 120 may include a damper, wherein the characteristics of the damper are fixed or electronically adjustable.

[0022] exist Figure 1B In the implementation scheme and in the discussion below, vehicle 100 is a battery electric vehicle. However, hybrid electric vehicles can also benefit from the methods described herein. Similarly, non-vehicle applications using inverters or other relevant power components can also benefit from the methods described herein.

[0023] Figure 2 Examples Figure 1A Example components of vehicle 100. (e.g.) Figure 2 As shown, vehicle 100 includes a camera 102, one or more front displays 104, a user interface 200, one or more sensors 202, motion sensors 204 (e.g., vehicle speed sensor 204a, accelerometer 204b, or other types of motion sensors), and a positioning system 206. The one or more sensors 202 may include ultrasonic sensors, radio detection and ranging (RADAR) sensors, light detection and ranging (LIDAR) sensors, or other types of sensors. The positioning system 206 may be implemented as a Global Positioning System (GPS) receiver. The user interface 200 allows a user (such as a driver or passenger in vehicle 100) to provide input.

[0024] Components of vehicle 100 may include one or more temperature sensors 208. Temperature sensors 208 may include sensors configured to sense ambient air temperature, battery 110 temperature, power module 114 temperature, temperature of each drive unit 112 and / or each motor of each drive unit 112 temperature, temperature of coolant fluid entering or leaving the coolant system, oil temperature within drive unit 112, or the temperature of any other component of vehicle 100. Temperature sensors 208 may include temperature sensors directly mounted to the microprocessor of power module 114, as described in more detail below.

[0025] The control system 214 executes instructions to perform at least some of the actions or functions of the vehicle 100. For example, such as... Figure 2As shown, the control system 214 may include one or more electronic control units (ECUs) configured to perform at least some of the actions or functions of the vehicle 100, including the functions described below. In some embodiments, each ECU is dedicated to a specific set of functions.

[0026] Some features of the implementation described herein can be controlled by a telematics control module (TCM) ECU. The TCM ECU may provide a wireless vehicle communication gateway to support functionality, by way of example and not limitation, such as over-the-air (OTA) software updates, vehicle-to-Internet communication, vehicle-to-computing device communication, in-vehicle navigation, vehicle-to-vehicle communication, vehicle-to-landscape features (e.g., automatic toll collection sensors, automatic toll booths, power distributors at charging stations), or automatic calling functionality.

[0027] Some features of the embodiments described herein can be controlled by a Central Gateway Module (CGM) ECU. The CGM ECU serves as the vehicle's communication hub, connecting various ECUs, sensors, cameras, microphones, motors, displays, and other vehicle components, and transmitting data to and from these components. The CGM ECU may include a network switch providing connectivity via a Controller Area Network (CAN) port, a Local Interconnect Network (LIN) port, and an Ethernet port. The CGM ECU can also function as the master controller for different vehicle modes (e.g., road driving mode, parking mode, off-road mode, towing mode, camping mode), thereby controlling certain vehicle components associated with placing the vehicle in one of these vehicle modes.

[0028] In various implementations, the CGM ECU collects sensor signals from one or more sensors of the vehicle 100. For example, the CGM ECU may collect data from camera 102, sensor 202, motion sensor 204, positioning system 206, and temperature sensor 208. The sensor signals collected by the CGM ECU are then transmitted to the appropriate ECU for processing.

[0029] The control system 214 may also include one or more additional ECUs, as an example and not a limitation, such as a vehicle dynamics module (VDM) ECU, an experience management module (XMM) ECU, a vehicle access system (VAS) ECU, a near field communication (NFC) ECU, a body control module (BCM) ECU, a seat control module (SCM) ECU, a door control module (DCM) ECU, a rear zone control (RZC) ECU, an autonomous control module (ACM) ECU, an autonomous safety module (ASM) ECU, a driver monitoring system (DMS) ECU, and / or a winch control module (WCM) ECU.

[0030] If vehicle 100 is an electric vehicle, one or more ECUs may provide functionality related to the vehicle's battery pack, such as a Battery Management System (BMS) ECU, a Battery Power Isolation (BPI) ECU, a Balanced Voltage and Temperature (BVT) ECU, and / or a Thermal Management Module (TMM) ECU. In various implementations, the XMM ECU sends data to the TCM ECU (e.g., via Ethernet, etc.). Additionally or alternatively, the XMM ECU may send other data (e.g., audio data from microphone 216, etc.) to the TCM ECU.

[0031] refer to Figure 3A The dynamics of the chassis 106 relative to the wheels of the vehicle 100 can be understood relative to all mutually perpendicular X, Y, and Z directions. The X direction (also known as the longitudinal direction) can be defined as the direction of travel when the vehicle 100 travels in a straight line, and the Z direction (also known as the vertical direction) can be understood as the direction of gravity when the vehicle 100 is on a flat support surface. The Y direction (also known as the lateral direction) is perpendicular to the X and Y directions.

[0032] The wheels of vehicle 100 include a left front wheel 300a, a right front wheel 300b, a left rear wheel 300c, and a right rear wheel 300d. The front wheels 300a and 300b are typically steered, although all-wheel steering is also possible. The motion of the chassis 106 relative to the wheels 300a to 300d may include roll 302a (rotation about an axis parallel to the X direction), pitch 302b (rotation about an axis parallel to the Y direction), and yaw 302c (rotation about an axis parallel to the Z direction). Lateral acceleration 304, as discussed herein, can be defined as acceleration parallel to the Y direction. Lateral jerk, as discussed herein, can be defined as the first derivative of lateral acceleration 304.

[0033] The suspension 120 for each wheel 300a to 300d can independently control forces resisting movement of the chassis 106 relative to the wheels 300a to 300d in two directions generally parallel to the Z direction (e.g., within 10 degrees). These forces may include a compressive force 310 resisting compression of the suspension 120 (e.g., downward movement of the chassis 106 relative to the wheels 300a to 300d along the Z direction) and a rebound force 312 resisting expansion of the suspension 120 (e.g., upward movement of the chassis 106 relative to the wheels 300a to 300d along the Z direction).

[0034] Figure 3B A simplified representation of a suspension 120 for wheels 300a to 300d is illustrated. The suspension 120 may include a spring inserted between the chassis 106 and a link 320 (such as a control arm) connecting the wheels 300a to 300d to the chassis 106. The spring may be an air spring 322, such that its effective spring constant can be dynamically changed to adjust the ride height of the vehicle 100 and compensate for steady-state forces (e.g., low-frequency, e.g., less than 1 Hz) causing body roll 302a. The air spring 322 may be replaced by any other type of spring, such as a coil spring or a leaf spring. The air spring 322 provides restoring force in response to forces applied to the wheels 300a to 300d and inertial forces applied by the chassis 106.

[0035] The suspension 120 may also include a damper 324 connected between the chassis 106 and the linkage 320, and this damper resists movement of the chassis 106 relative to the wheels 300a to 300d. The resistance is primarily (e.g., at least 90%) inelastic, for example, due to viscous losses. The damper 324 can be used to limit oscillations caused by the spring-mass system formed by the chassis 106 and the air spring 322. As discussed in more detail below, the damper 324 can also be used to control the amount of body roll 302a during cornering.

[0036] In some embodiments, the damper 324 is implemented or behaves similarly to a cylinder 326 and a piston 328 sliding within the cylinder 326. Hydraulic fluid within the cylinder 326 can be discharged from the cylinder 326 via valves 328a, 328b positioned on either side of the piston 328. For example, flow through valve 328a can be caused by compression of the suspension 120 (movement of the chassis 106 toward the link 320), and thus defines the amount of compressive force 310 applied by the damper 324. Flow through valve 328b can be caused by rebound of the suspension 120 (movement of the chassis 106 away from the link 320), and thus defines the amount of rebound force 312 applied by the damper 324. Valves 328a, 328b can be connected to each other: fluid flowing out of valve 328a flows into valve 328b, and vice versa. Alternatively, the pressure downstream of valves 328a and 328b can be regulated by a hydraulic system 330, which provides a reservoir for hydraulic fluid and may maintain the pressure at valves 328a and 328b.

[0037] Each wheel 300a to 300d has a corresponding suspension 120, and components of the suspension (e.g., cylinder 326, valves 328a, 328b, cylinder 326) are referred herein to as corresponding to the wheel 300a to 300d or to the wheel 300a to 300d corresponding to such components.

[0038] Although the examples in this article refer to hydraulic dampers, once the damping force is determined according to the methods described below, the damping force can be achieved using any type of damper known in the art.

[0039] Figure 4 A method for controlling valves 328a and 328b for damper 324 is illustrated. Figure 4 This can be achieved using a control system 214, such as one or more ECUs. For example, a vehicle dynamics module (VDM) can be used. Figure 4 The methods executor the components and the corresponding methods implemented by performing the functions belonging to those components, as described below.

[0040] exist Figure 4 In the method, command phase 400 can generate valve command 402 for each valve 328a, 328b of each suspension 120. Valve command 402 for valves 328a, 328b can command the degree of opening of valves 328a, 328b and the stress (compression force 310 or rebound force 312) applied by dampers 324 including valves 328a, 328b.

[0041] Command phase 400 can generate valve command 402 corresponding to valves 328a, 328b of wheels 300a to 300d based on damping force 404 determined for wheels 300a to 300d. Figure 4 A method for determining the damping force 404 is illustrated, which is based on a large number of input signals while requiring adjustment of relatively few parameters to achieve the desired vehicle handling characteristics.

[0042] Input signals may include steering rate 406a, such as the rate of change of steering angle of the steering wheels (e.g., front wheels 300a, 300b) applied by the driver, an autonomous driving algorithm, or a combination thereof. Input signals may include lateral acceleration 406b and lateral jerk 406c as defined above. Lateral acceleration 406b may be sensed by accelerometer 204b incorporated into vehicle 100, and lateral jerk 406c may be calculated as the first derivative of lateral acceleration 406b. Yaw rate 406d (e.g., rotation in yaw 302c) may also be derived from rotation sensed by accelerometer 204b.

[0043] Other input signals may include, for example, vehicle speed 406e measured by speed sensor 204a, which measures the rotation of one or more wheels 300a to 300d or other components of the drivetrain of vehicle 100. The vehicle's currently selected driving mode 406f may also be used as an input. In some embodiments, steering angle 406g and longitudinal acceleration 406h (e.g., sensed by accelerometer 204b or based on driver input to the accelerometer and brake pedals) are also used as input signals.

[0044] As described above, there are numerous input signals 406a to 406h. The benefits of the method described herein can be achieved using only two or more of the input signals 406a to 406d and the vehicle speed 406e. In one example, steering rate 406a, lateral acceleration 406b, and lateral jerk 406c are used together with vehicle speed 406e. However, as described in detail below, further improvements can be achieved using one or more additional input signals from the input signals 406a to 406h.

[0045] A portion of the input signal is designated as "roll-related input signal" and may include, for example, steering rate 406a, and one or more of lateral acceleration 406b, lateral jerk 406c, or yaw rate 406d, such as at least lateral acceleration 406b and lateral jerk 406c. The roll-related input signal may be input to a normalization stage 408. Normalizing the input signal may include: calculating the absolute value of each input signal and scaling the absolute value of the input signal such that each input signal ranges only between 0 and 1. For example, the roll-related input signal may be normalized according to (|S| / SF), where |S| is the absolute value of the signal (e.g., a sample of the signal), and SF is a scaling factor for the input signal. Normalization may include constraining the normalized value between 0 and 1. (|S| / SF) may be used where |S| cannot exceed SF and / or a normalized value greater than 1 is permissible. Otherwise, other clamping methods can be used (e.g., minimum value (|S| / SF, 1, (2 / π)*atan(|S| / SF)).

[0046] The value of SF can be selected experimentally. For example, an instance of vehicle 100 can be subjected to handling tests involving turning at various speeds and turning radii to determine the safe operating limits of vehicle 100 (e.g., avoiding rollover, skidding, understeer, oversteer, etc.). During such handling tests, the value of an input signal related to body roll can be measured when vehicle 100 is operating within its safe operating limits, and the maximum amplitude of the measured input signal (possibly reduced by a safety factor) can be used as the value of SF for that input signal. As discussed in detail below, the value of SF can be selected based on such measurements and taking into account other considerations.

[0047] The output of normalization stage 408 is a set of two or more normalized signals corresponding to two or more input signals related to vehicle body roll. The normalized signals can be processed by combination stage 410 to obtain a single combined signal. The combination stage can combine the normalized signals by summing them. Alternatively, the combination stage can combine the normalized signals by taking the maximum value of the normalized signals (e.g., the largest sample of the normalized signals for a given time step).

[0048] The combined signal can be input to the filter / deadband stage 412. The filter / deadband stage 412 can perform low-pass filtering on the combined signal. The input signal related to vehicle roll and the corresponding combined signal include high-frequency components (e.g., noise), while the vehicle 100 has a relatively low frequency response (e.g., less than 2 Hz). Therefore, the filter / deadband stage 412 can filter the combined signal using a low-pass filter to obtain a filtered signal. The low-pass filter can have a cut-off frequency (e.g., 3 dB cut-off frequency) between 1.5 Hz and 2.5 Hz, between 1.8 Hz and 2.2 Hz, or between 1.9 Hz and 2.1 Hz.

[0049] The filter / deadband stage 412 can clamp the filtered signal to zero under certain conditions (i.e., within the deadband). For example, at high vehicle speeds, a small change in the input signal related to vehicle roll may not be helpful for changing the damping behavior. Therefore, the filter / deadband stage 412 can implement logic such as: if (FS[t] < F(V)), then FS[t] = 0, where FS[t] is a sample in the filtered signal, V is the vehicle speed 406e, and F(V) is a function of vehicle speed that increases as the vehicle speed increases. For example, the width of the deadband increases as the speed increases. F(V) can be implemented as a mathematical function, a look-up table, or other logic.

[0050] The filter / deadband stage 412 can be a function of the driving mode 406f of the vehicle. For example, for a racing driving mode that emphasizes reducing vehicle roll more than comfort, the width of the deadband can be reduced or eliminated. For a comfort driving mode that emphasizes comfort more than reducing vehicle roll, the deadband can be larger. For example, for a given vehicle speed V, F(V) in the comfort driving mode is larger than F(V) in the racing driving mode.

[0051] The filtered signal output by the filter / deadband stage 412 can be input to the force calculation stage 414. The force calculation stage 414 uses the filtered signal and one or more input signals other than the input signal related to vehicle roll, such as the vehicle speed 406e and possibly the driving mode 406f. The output of the force calculation stage 414 is a common damping force, which is used in subsequent stages to determine the specific damping force 404 for each valve 328a, 328b of each damper 324.

[0052] In the force calculation phase 414, Table 414a can be used to calculate the common damping force, which provides the common damping force based on the value of the filtered signal and the value of the vehicle speed 406e. Table 414a can be a three-dimensional table that provides the common damping force for the value of the filtered signal, the vehicle speed 406e, and the driving mode 406f. Table 414a has a finite number of entries, allowing for interpolation. Table 414a can also be replaced by mathematical functions or programming logic for selecting the common damping force based on input variables (filtered signal, speed, and possible driving mode).

[0053] Table 414a provides a single data structure that, considering speed and body roll-related inputs, defines the vehicle handling associated with damper 324. Specifically, Table 414a provides a single data structure for handling instantaneous body roll caused by the initiation of a turn, the end of a turn, and changes in the steering angle during a turn. Therefore, this table provides designers with a convenient data structure to test possible vehicle behaviors when adjusting the handling of vehicle 100 associated with damper 324.

[0054] The common damping force output from the force calculation stage 414 can be input to the left / right adjustment stage 416. The left / right adjustment stage 416 can also take steering rate 406a and possible steering angle 406g as inputs. The left / right adjustment stage 416 determines the sign of the damping force (e.g., compression force 310 or rebound force 312) applied by the dampers 324 of each wheel 300a to 300d, and can further adjust the common damping force. The output of the left / right adjustment stage 416 can be the left damping force and the right damping force.

[0055] As described above, the normalization stage 408 can take the absolute value of the input signal related to vehicle body roll, so that the direction of the common damping force is unknown. Therefore, the left / right adjustment stage 416 can determine the signs of the left and right damping forces (e.g., compression force 310 = positive; rebound force 312 = negative), where the magnitude of the force is determined based on the common damping force.

[0056] For example, a positive steering rate can be defined as an increasing steering to the left, and a negative steering rate can be defined as an increasing steering to the right. Similarly, a positive steering angle can be defined as the right side of the straight-forward position of the steering wheel, and a negative steering angle can be defined as the left side of the straight-forward position. The left / right adjustment phase 416 can use the steering rate 406a and the possible steering angle 406g to determine the left damping force and the right damping force.

[0057] For example, a positive (left) steering rate can indicate a tendency for the vehicle to lean to the right, such that the right damping force is positive (non-zero compressive force 310) and the left damping force is negative (non-zero rebound force 312). A negative (right) steering rate can indicate a tendency for the vehicle to lean to the left, such that the left damping force is positive and the right damping force is negative.

[0058] The magnitudes of the left and right damping forces can be set to be equal to the common damping force, half of the common damping force, or some other function of the common damping force. For example, which of the left and right damping forces is positive can be set as P*C, and which of the left and right damping forces is negative can be set as N*C, where C is the common damping force, and P and N are predetermined values ​​that can be unequal. For example, P can be greater than N.

[0059] The left / right adjustment phase 416 can also take the steering angle 406g as input. For example, the left and right damping forces, as determined above, can be adjusted based on the steering angle 406g. In one application, in response to a zero crossing of the steering angle 406g (e.g., a change from a right turn to a left turn), the magnitudes of the left and right damping forces can be increased relative to the magnitude based on the common damping force. In this way, as the turn proceeds, the corresponding valves 328a, 328b will close more quickly in anticipation of the greater damping force demand, thereby allowing the pressure in cylinder 326 to begin increasing more quickly and compensating for the inherent delay in changing the state of valves 328a, 328b.

[0060] The left and right damping forces determined by the left / right adjustment stage 416 can be input to the front / rear adjustment stage 418, which generates a damping force 404. The front and rear suspensions 120 can be different (e.g., different spring constants), and the weight distribution on the front wheels 300a, 300b and the rear wheels 300c, 300d can be different. Therefore, the left damping force can be processed by the left / right adjustment stage 416 to obtain a left front damping force 404 and a left rear damping force 404. The right damping force can be processed by the left / right adjustment stage 416 to obtain a right front damping force 404 and a right rear damping force 404.

[0061] For example, based on the load of vehicle 100 or the inherent weight distribution of vehicle 100, the rear wheels 300c and 300d may bear a greater load than the front wheels 300a and 300b. Therefore, the left front damping force 404 can be calculated as F*LD, and the left rear damping force can be calculated as R*LD, where LD is the left damping force, and F and R are values ​​chosen to achieve the desired ratio between the front and rear damping forces. For example, R can be greater than F, where the rear wheels 300c and 300d bear a greater load than the front wheels 300a and 300b. Similarly, the right front damping force 404 can be calculated as F*RD, and the right rear damping force can be calculated as R*RD, where RD is the right damping force.

[0062] In some implementations, the damping force 404 can be further adjusted based on longitudinal acceleration. For example, during positive acceleration, the load is transferred to the rear wheels 300c and 300d and away from the front wheels 300a and 300b. During negative acceleration (e.g., braking), the load is transferred away from the rear wheels 300c and 300d and transferred to the front wheels 300a and 300b. For the wheel 300a to 300d that experiences a greater load due to acceleration, the damping force 404 can be increased, and for the wheel 300a to 300d that experiences a smaller load due to acceleration, the damping force can be decreased.

[0063] For example, the magnitudes of the left front damping force 404 and the right front damping force 404 can be adjusted or scaled by GF(a), and the left rear damping force 404 and the right rear damping force 404 can be enhanced or scaled by GR(a), where a is acceleration, GF(a) is a function of acceleration that decreases as acceleration increases, and GR(a) is a function of acceleration that increases as acceleration increases.

[0064] Command phase 400 uses damping force 404 to generate valve command 402. For example, a positive damping force 404 corresponding to wheels 300a to 300d will cause valve 328a corresponding to the damper 324 of those wheels 300a to 300d to close, thereby achieving a compressive force 310 corresponding to the magnitude of the positive damping force 404, and will cause valve 328b to open to reduce the rebound force 312. A negative damping force 404 corresponding to wheels 300a to 300d will cause valve 328a corresponding to the damper 324 of those wheels to open, thereby reducing the compressive force 310 corresponding to the magnitude of the positive damping force 404, and will cause valve 328b to close to increase the rebound force 312 corresponding to the magnitude of the negative damping force 404.

[0065] For example, command stage 400 can generate valve command 402 as follows:

[0066] ● The positive left front damping force 404 may cause the corresponding valve 328a to close and the valve 328b to open, corresponding to the wheel 300a.

[0067] ● Negative left front damping force may cause the corresponding valve 328a to open and the valve 328b to close, corresponding to wheel 300a.

[0068] ● The right front damping force 404 may cause the corresponding valve 328a to close and the valve 328b to open, corresponding to the wheel 300b.

[0069] ● The negative right front damping force 404 may cause the corresponding opening of valve 328a and the closing of valve 328b corresponding to wheel 300b.

[0070] ● The positive left rear damping force 404 may cause the corresponding valve 328a to close and the valve 328b to open, corresponding to the wheel 300c.

[0071] ● The negative left rear damping force 404 may cause the corresponding valve 328a to open and the valve 328b to close, corresponding to the wheel 300c.

[0072] ● The right rear damping force 404 may cause the corresponding valve 328a to close and the valve 328b to open, corresponding to wheel 300d.

[0073] ● The negative right rear damping force 404 may cause the command corresponding to the opening of valve 328a and the closing of valve 328b of wheel 300d.

[0074] Valve command 402 can be directly input to the actuators that control the opening and closing of valves 328a and 328b, or can be used as a target by one or more controllers that control the actuators.

[0075] Figure 4 The system described is merely exemplary and can be modified in various ways to further improve its operation. For example, the normalization stage 408 can be used to change the weighting of input signals (steering rate 406a, lateral acceleration 406b, lateral jerk 406c, and yaw rate 406d) related to body roll. In one approach, the value of SF used to normalize the input signals can be selected by the scaling factor selection stage 420 based on driving mode 406f. In one example, for a first (e.g., racing) driving mode, emphasis can be placed on steering rate 406a to reduce body roll and provide greater responsiveness to driver input. Therefore, the value of SF used to normalize steering rate 406a can be reduced relative to other driving modes, resulting in a greater contribution of steering rate 406a to the common damping force. In a second (e.g., comfort) driving mode, emphasis can be placed on comfort relative to reducing body roll and responsiveness, such that the value of SF used to normalize steering rate 406a can be greater than the value of SF used in the racing driving mode.

[0076] In another example modification, the roll-related input signal can be shaped (e.g., scaled, filtered, processed, etc. according to a transfer function) based on one or more other input signals (such as vehicle speed 406e and driving mode 406f) before or in place of the normalization stage 408. The shaping of the roll-related input signal can be performed based on lookup tables, mathematical functions, programming logic, or other methods.

[0077] In another example modification, the order of certain steps can be reversed. For example, in the normalization stage, scaling by SF can be performed before taking the absolute value. The order of filtering and clamping within the dead zone can also be reversed relative to the order described above with respect to filter / dead zone stage 412. The order of left / right adjustment stage 416 and front / rear adjustment stage 418 can also be reversed. Therefore, the front and rear damping forces can first be calculated based on the weight distribution, suspension configuration, and / or longitudinal acceleration 406h as described above. The front damping force can then be used to calculate the left front damping force 404 and right front damping force 404 based on steering rate 406a and possible steering angle 406g. The rear damping force can then be used to calculate the left rear damping force 404 and right rear damping force 404 based on steering rate 406a and possible steering angle 406g, as described above.

[0078] Figure 5A and Figure 5B The graph includes input signals related to vehicle body roll and illustrates the operation of the system shown in Figure 5. Figure 5A In the diagram, curve 500a represents the turning rate (degrees / second), curve 500b represents the lateral acceleration (meters / second squared), and curve 500c represents the lateral jerk (meters / second cubic). Figure 5B In the diagram, curve 502a is the normalized steering rate curve, curve 502b is the normalized lateral acceleration curve, and curve 502c is the normalized lateral jerk curve. Curve 502d is the curve of the combined signal obtained from the normalized input signal. Figure 5A and Figure 5B The curve corresponds to a turning event, which includes turning in, stabilizing the turn (e.g., the steering angle is relatively constant), mid-event correction, and bringing the steering wheels straight at the end of the turning event.

[0079] It is evident that the amplitudes of these signals differ significantly before normalization. It is further apparent that, after normalization, which signal in the normalized signal varies considerably throughout the turning event. For example, the normalized steering rate (curve 502a) dominates during the turn-in phase, while the normalized lateral acceleration (curve 502b) dominates during the steady turn. During intermediate event correction and straight-line travel, all three normalized input signals contribute to the combined signal and exhibit peaks occurring at different times from each other. Using the method described above, the combined signal obtained from the normalized signal captures the contribution of any one of the input signals that dominates at a given stage of the turning event from the input signals related to vehicle roll.

[0080] The combined signal is also used to smooth variations in the individual input signals, resulting in smoother control of the damper 324, particularly during intermediate event corrections and straight-line travel. For example, during intermediate event corrections, the normalized steering rate will tend to indicate the slope of the common damping force, further shaped by normalized lateral acceleration and lateral jerk to reflect vehicle behavior. During straight-line travel, all three normalized input signals are blended to ensure stable support for the vehicle as it exits a cornering event.

[0081] Various embodiments of this disclosure have been described for illustrative purposes. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein has been chosen to explain the principles of the embodiments, their practical application, or technical improvements to technologies found in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

[0082] In the foregoing, reference has been made to the embodiments presented in this disclosure. However, the scope of this disclosure extends beyond the specifically described embodiments. Rather, any combination of features and elements is contemplated for implementing and practicing the intended embodiments, regardless of whether different embodiments are involved. Furthermore, while the embodiments disclosed herein may achieve advantages over other possible solutions or over the prior art, the embodiments may achieve some advantages or no particular advantages. Therefore, the aspects, features, embodiments, and advantages discussed herein are merely illustrative.

[0083] While the foregoing relates to embodiments of this disclosure, other and further embodiments may be devised without departing from the basic scope of this disclosure, the scope of which is defined by the appended claims.

Claims

1. A control system for use in a vehicle, the control system being configured to: Receive two or more input signals related to the vehicle's body roll; The two or more input signals are combined to obtain a combined signal; The common damping force is calculated based on the combined signal and the vehicle's speed. The common damping force is processed to calculate the damping force corresponding to each of the multiple wheels of the vehicle. as well as The operation of the vehicle's damper, corresponding to each of the plurality of wheels, is commanded based on the damping force corresponding to each wheel.

2. The control system of claim 1, wherein the control system is configured to normalize the two or more input signals to obtain two or more normalized signals, and to combine the two or more normalized signals to obtain the combined signal.

3. The control system of claim 2, wherein the control system is configured to normalize each of the two or more input signals by dividing the absolute value of each input signal by a scaling factor corresponding to each input signal.

4. The control system of claim 2, wherein the control system is configured to combine the two or more normalized signals by summing the two or more normalized signals.

5. The control system of claim 2, wherein the control system is configured to combine the two or more normalized signals by taking the maximum value of the two or more normalized signals.

6. The control system of claim 1, wherein the control system is configured to use a lookup table to calculate the common damping force based on the combined signal and the speed of the vehicle.

7. The control system of claim 1, wherein the control system is configured to calculate the common damping force based on the combined signal, the speed of the vehicle, and the driving mode of the vehicle.

8. The control system of claim 1, wherein the two or more input signals include the vehicle's steering rate and lateral acceleration.

9. The control system of claim 8, wherein the two or more input signals include lateral jerk.

10. The control system of claim 9, wherein the two or more input signals include the yaw rate of the vehicle.

11. The control system of claim 1, wherein the control system is configured to process the common damping force to calculate the damping force corresponding to each of the plurality of wheels of the vehicle in such a way as follows: The left and right damping forces are calculated from the common damping force based on the vehicle's steering rate; and The damping force corresponding to each left wheel of the plurality of wheels is calculated based on the left damping force, and the damping force corresponding to each right wheel of the plurality of wheels is calculated based on the right damping force.

12. The control system of claim 11, wherein the control system is configured to calculate the left damping force and the right damping force from the common damping force based on the steering rate and steering angle of the vehicle.

13. The control system of claim 11, wherein the control system is configured to calculate the damping force corresponding to each left wheel of the plurality of wheels based on the left damping force and to calculate the damping force corresponding to each right wheel of the plurality of wheels based on the right damping force: The damping forces for the left front wheel and the left rear wheel are calculated based on the left damping force and the longitudinal acceleration of the vehicle; and The damping force for the right front wheel and the right rear wheel among the plurality of wheels is calculated based on the right damping force and the longitudinal acceleration of the vehicle.

14. The control system of claim 1, wherein the control system is configured to: The combined signal is filtered using a low-pass filter to obtain a filtered signal, and the common damping force is calculated based on the combined signal and the vehicle's speed; and The common damping force is calculated based on the filtered signal and the vehicle's speed.

15. The control system of claim 14, wherein the low-pass filter has a cutoff frequency of 1.5 Hz to 2.5 Hz.

16. A vehicle, the vehicle comprising: Chassis; Multiple wheels; Multiple suspensions, each of which connects a plurality of wheels to the chassis, include a damper; and The control system is configured to: Receive two or more input signals related to the vehicle's body roll; The two or more input signals are combined to obtain a combined signal; The common damping force is calculated based on the combined signal and the vehicle's speed. The common damping force is processed to calculate the damping force corresponding to each of the multiple wheels of the vehicle. as well as The operation of the vehicle's damper, corresponding to each of the plurality of wheels, is commanded based on the damping force corresponding to each wheel.

17. The vehicle of claim 16, wherein the control system is configured to normalize the two or more input signals to obtain two or more normalized signals, and to combine the two or more normalized signals to obtain the combined signal.

18. The vehicle of claim 17, wherein the control system is configured to combine the two or more normalized signals by one of the following methods: summing the two or more normalized signals, and taking the maximum value of the two or more normalized signals.

19. The vehicle of claim 16, wherein the control system is configured to calculate the common damping force based on the combined signal, the speed of the vehicle, and the driving mode of the vehicle.

20. A damper control method, the damper control method comprising: The vehicle's control system receives two or more input signals related to the vehicle's body roll. The control system combines the two or more input signals to obtain a combined signal; The control system calculates the common damping force based on the combined signal and the vehicle speed; The control system processes the common damping force to calculate the damping force corresponding to each of the multiple wheels of the vehicle. as well as The control system commands the operation of the vehicle's damper corresponding to each of the plurality of wheels of the vehicle based on the damping force corresponding to each wheel.

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