DEVICE AND METHOD FOR CONTROLLING AN ACTUATOR USING VIBRATION ANALYSIS TECHNIQUE

Abstract

A method for controlling an actuator may include calculating an input load received by or acting upon a vehicle suspension system, including a spring unit and / or a damper unit and / or a vibration isolation unit or isolator; decomposing the calculated input load received by the suspension system for each of the frequencies by a frequency decoder; generating control signals for each of the frequencies to control the spring unit and / or the damper unit and / or the vibration isolation unit or isolator included in the suspension system; and applying the control signals generated for each of the frequencies to the spring unit and / or the damper unit and / or the vibration isolation unit or isolator included in the suspension system to control the spring unit and / or the damper unit and / or the vibration isolation unit or isolator.

Description

CROSS-REFERENCE TO A RELATED APPLICATION

[0001] This application claims priority under 35 USC §119 to Korean Patent Application No. 10-2023-0143754, filed on October 25, 2023, in the Korea Intellectual Property Office (KIPO), the disclosure of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present disclosure generally relates to an apparatus and method for controlling an actuator to improve ride comfort and steering stability using a vibration analysis technique. In particular, some embodiments of the present disclosure may provide an apparatus and method for controlling an actuator to ensure optimal ride comfort and steering stability by analyzing a chassis input load and controlling actuators using vibration analysis techniques. BACKGROUND

[0003] A vehicle's ride comfort and steering stability are important factors in the ride quality experienced by the driver and passengers. They can be influenced by road irregularities, the vehicle's speed and handling, as well as a variety of external environmental factors. To improve this ride comfort and steering stability, various components of a suspension system have been researched and developed.

[0004] The main suspension components, such as springs, dampers (or shock absorbers), and vibration-damping rubbers, are typically designed to be individually optimized. That is, each component is tuned to its own target performance. For example, springs are primarily designed to support the weight of a vehicle, dampers are designed to control vibrations caused by road irregularities, and vibration-damping rubbers are designed to reduce vibration and noise. Various approaches exist to improve the ride comfort and steering stability of vehicles, for example, in Korean Patent Nos. 10-2395275 and 10-0593416. [Related patent documents] (1) Korean Patent No. 10-2395275 (granted on May 2, 2022) (2) Korean Patent No. 10-0593416 (granted on June 19, 2006) SUMMARY

[0005] The present disclosure can provide optimal ride comfort and steering stability by analyzing an input load acting on a suspension system using vibration analysis techniques and controlling individual actuators.

[0006] However, the technical problems to be solved by the present disclosure are not limited to those described above, and other technical problems may also arise.

[0007] A method for controlling an actuator for improving ride comfort and steering stability according to an embodiment of the present disclosure may include: calculating an input load to be received by a suspension system of a vehicle including a spring unit, a damper unit, and / or a vibration isolator unit; decomposing the calculated input load received by the suspension system for each frequency by a frequency decoder; generating control signals for each of the frequencies to control the spring unit, the damper unit, and / or the vibration isolator unit included in the suspension system;and supplying the control signals generated for each of the frequencies to the spring unit and / or the damper unit and / or the vibration isolator unit included in the suspension system to control at least one of the spring unit, the damper unit and the vibration isolator unit;

[0008] According to an embodiment of the present disclosure, the calculation of the input load may be that the input load is calculated by detecting the movement of the vehicle body and / or the spring unit and / or the damper unit by a sensor when the vehicle passes the road surface with the corresponding profile.

[0009] According to an embodiment of the present disclosure, the calculation of the input load may be that the input load is calculated by receiving the profile of the road surface from a sensor for inputting information about a front area or a high-definition (HD) map.

[0010] According to an embodiment of the present disclosure, examples of the sensor for inputting information about the front area may include a preview camera, a LiDAR (Light Detection and Ranging), a high-resolution camera, a RADAR, an inertial measurement unit (IMU), a GPS (Global Positioning System), a ToF (Time-of-Flight) camera, a thermal camera, and a stereo camera.

[0011] According to an embodiment of the present disclosure, the frequencies may include at least a first frequency in a first frequency band, a second frequency in a second frequency band, and a third frequency in a third frequency band.

[0012] According to an embodiment of the present disclosure, the spring unit may comprise a coil spring or an air spring; in the coil spring, only the stroke may be controlled by a stroke function in the first frequency; the air spring may be controlled by the pump capacity and the compressibility of a fluid in the first frequency; the damper unit may be controlled according to the properties of a valve as a speed function in the second frequency; and the vibration isolator unit may be controlled by the properties of variable materials in the third frequency.

[0013] According to an embodiment of the present disclosure, the first frequency may be in a range of 0 Hz to 5 Hz, the second frequency may be in a range of 3 Hz to 25 Hz, and the third frequency may be in a range of 20 Hz to 250 Hz.

[0014] According to an embodiment of the present disclosure, the following steps may be included: calculating an input load received by an active suspension of a vehicle during travel; decomposing the calculated input load received by the active suspension for each frequency by a frequency decoder; generating control signals for each of the frequencies to control the active system; and applying the control signals generated for each of the frequencies to the active suspension to control the active suspension.

[0015] A method for controlling an actuator for improving ride comfort and steering stability according to another embodiment of the present disclosure may include: a) setting a target ride comfort expressed in indices; b) calculating an input load received from a suspension system of the vehicle including a spring unit, a damper unit, and / or a vibration isolator unit; c) decomposing the calculated input load received from the suspension system for each frequency by a frequency decoder; d) generating control signals for each of the frequencies to control at least one of the spring unit, the damper unit, and the vibration isolator unit included in the suspension system;e) applying the control signals generated for each of the frequencies to at least one of the spring unit, the damper unit, and the vibration isolator unit included in the suspension system to control the spring unit and / or the damper unit and / or the vibration isolator unit; and f) determining whether the desired ride quality is achieved and repeating steps b) to e) until the desired ride quality is achieved.

[0016] According to an embodiment of the present disclosure, calculating the input load may include calculating the profile of the road surface by detecting the movement of at least one of the vehicle body, spring unit, and damper unit with a sensor as the vehicle travels over the road surface.

[0017] According to an embodiment of the present disclosure, the calculation of the input load may be that the input load is calculated by receiving the profile of the road surface from a sensor for inputting information about a front area or a high-definition (HD) map.

[0018] According to an embodiment of the present disclosure, the frequencies may include at least a first frequency in a first frequency band, a second frequency in a second frequency band, and a third frequency in a third frequency band.

[0019] According to an embodiment of the present disclosure, the spring unit may comprise a coil spring or an air spring; in the coil spring, only the stroke may be controlled by a stroke function in the first frequency; the air spring may be controlled by the pump capacity and the compressibility of a fluid in the first frequency; the damper unit may be controlled according to the properties of a valve as a speed function in the second frequency; and the vibration isolator unit may be controlled by the properties of variable materials in the third frequency.

[0020] According to an embodiment of the present disclosure, the first frequency may be in a range of 0 Hz to 5 Hz, the second frequency may be in a range of 3 Hz to 25 Hz, and the third frequency may be in a range of 20 Hz to 250 Hz.

[0021] According to an embodiment of the present disclosure, the index or index may be determined based on a combination of one or more of the index elements primary handling, bump harshness / harshness, rough handling, judder vibration, suspension noise, steering feel, yaw response and damping, steering linearity, and roll stability.

[0022] An apparatus for controlling an actuator for improving ride comfort and steering stability according to another embodiment of the present disclosure may include: a suspension system including at least a spring unit, a damper unit, and a vibration isolator unit, and an input load calculation unit that calculates an input load received from the suspension system; a frequency decoder that decomposes the input load measured by sensors for each frequency by the fast Fourier transform (FFT); a microcontroller unit (MCU) that generates a control value for an actuator that controls at least one of the spring unit, the damper unit, and the vibration isolator unit included in the suspension system, based on a target ride comfort expressed in characteristics.desired driving comfort; and an electronic control unit (ECU) that receives the control value for the actuator from the microcontroller unit to generate a signal that controls the spring unit, the damper unit, and / or the vibration isolator unit.

[0023] According to an embodiment of the present disclosure, the MCU may calculate the difference between a result value of controlling the spring unit and / or the damper unit and / or the vibration isolator unit based on the input target ride comfort and a state value indicating the current state of a vehicle, and update the control value for the actuator to meet a predetermined target value.

[0024] According to an embodiment of the present disclosure, the input load calculation unit may calculate the input load by detecting the movement of the vehicle body and / or the spring unit and / or the damper unit via a sensor when the vehicle passes the profile of the road surface.

[0025] According to an embodiment of the present disclosure, the input load calculation unit may calculate the input load by obtaining the profile of the road surface from a front-end information input sensor or a high-definition (HD) map.

[0026] According to an embodiment of the present disclosure, the frequencies may include at least a first frequency in a first frequency band, a second frequency in a second frequency band, and a third frequency in a third frequency band.

[0027] According to an embodiment of the present disclosure, the spring unit may comprise a coil spring or an air spring; in the coil spring, only the stroke may be controlled by a stroke function in the first frequency; the air spring may be controlled by the pump capacity and the compressibility of a fluid in the first frequency; the damper unit may be controlled according to the properties of a valve as a speed function in the second frequency; and the vibration isolator unit may be controlled by the properties of variable materials in the third frequency.

[0028] According to an embodiment of the present disclosure, the first frequency may be in a range of 0 Hz to 5 Hz, the second frequency may be in a range of 3 Hz to 25 Hz, and the third frequency may be in a range of 20 Hz to 250 Hz.

[0029] According to the present disclosure, it may be possible to ensure optimal ride comfort and steering stability by analyzing an input load acting on a suspension system using vibration analysis techniques and controlling individual actuators for each frequency. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a block diagram illustrating an apparatus for controlling an actuator to improve ride comfort and steering stability according to an embodiment of the present disclosure. Fig. 2 is a spider web diagram showing ride comfort expressed in multiple characteristics according to an embodiment of the present disclosure. Fig. 3 is a schematic view showing the profile of a road surface and a suspension system according to an embodiment of the present disclosure. Fig. 4 is a diagram illustrating a frequency spectrum according to an embodiment of the present disclosure. Fig. 5 is a flowchart illustrating a method for controlling an actuator to improve ride comfort and steering stability of a vehicle according to an embodiment of the present disclosure. Fig. 6 is a flowchart illustrating a method of controlling an actuator to improve ride comfort and steering stability of a vehicle according to another embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that a person having ordinary skill in the art can easily practice the embodiments of the present disclosure. Since various changes are susceptible to the present disclosure and various embodiments are possible, specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, it is not intended to limit the present disclosure to specific embodiments, and the present disclosure should be understood to include all modifications, equivalents, or substitutes within the scope of the technology of the present disclosure.

[0031] To clearly describe the present disclosure, parts unrelated to the description have been omitted from the drawings, and similar parts have been designated with similar drawing reference numerals throughout the application. Furthermore, when describing the features with reference to the drawings, features with the same name may be designated with different reference numerals in each drawing. The drawing reference numerals are for convenience of description only, and the concept, characteristics, function, or effect of each feature is not limited by the reference numeral.

[0032] In describing the drawings, similar components are designated by similar reference numerals. Terms such as "first" and "second" may be used to describe different components, but the components should not be limited by the terms. Such terms are used only to distinguish one component from another. For example, a first component may be referred to as a second component, and similarly, the second component may be referred to as a first component throughout the present disclosure. The term "and / or" includes a combination of multiple related elements or any one of the multiple related elements.

[0033] Unless otherwise defined, all terms used herein, including technical or scientific terms, have a meaning commonly understood by a person of ordinary skill in the art to which this disclosure relates.

[0034] Terms defined in common dictionaries should be considered in the meaning they have in the context of a relevant technology and should not be interpreted in an idealized or overly formal sense unless they are expressly defined in the present disclosure.

[0035] When this disclosure refers to the "connection" of one part to another part, the part may be "directly" or "indirectly" connected to the other part, or "electrically" or "operably" connected to another element therebetween. When a part is said to "include" a particular component, this means that it may also include other components and does not exclude other components unless expressly stated otherwise, and should not be understood to preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0036] Hereinafter, an apparatus and method for controlling an actuator to improve ride comfort and steering stability using a vibration analysis technique according to the present disclosure will be described in detail with reference to the accompanying drawings.

[0037] Fig. 1 is a block diagram illustrating an apparatus for controlling an actuator to improve ride comfort and steering stability according to an embodiment of the present disclosure.

[0038] Referring to Fig. 1, an actuator control device 100 for improving ride comfort and steering stability may include a wheel G-sensor or wheel acceleration sensor 111, a height sensor 112, a preview camera 113, a LIDAR (Light Detection and Ranging) 114, a high-resolution (HD) map 115, a frequency decoder 120, 121 and 122, a microcontroller unit (MCU) 130, an electronic control unit (ECU) 140 and actuators 150-1, 150-2, ..., 150-n (n is a natural number equal to or greater than one).

[0039] The wheel G-sensor 111 may be a sensor that measures the G-forces in a wheel or tire. The wheel G-sensor 111 may provide information about traction, wheel slip, or other performance indicators related to how the wheels are in contact with the road.

[0040] The height sensor 112 may be used primarily in conjunction with an electronically controlled suspension system and may be configured to detect changes in the relative height between the height of the body and the wheels of a vehicle. The height sensor 112 may be implemented as various types of sensors, such as, but not limited to, a potentiometer, a Hall-effect sensor, or a piezoelectric sensor.

[0041] The wheel G sensor 111 and the height sensor 112 can be used to measure the profile of the road surface during driving and forward it to a first frequency decoder 121. The information or data acquired or detected by the wheel G sensor 111 and the height sensor 112 according to an embodiment of the present disclosure and forwarded to the first frequency decoder 121 can be information about the profile of the road surface, indicating the current condition of the road surface. Here, the profile of the road surface can refer to the measured results of measuring irregularities, defects, and height differences on the road surface, which affect the ride comfort when driving a vehicle. Such a profile can be used as an important indicator in evaluating road wear, damage, and service life, etc.and serve as an important reference in particular when designing a vehicle suspension or repairing roads.

[0042] The preview camera 113 can be equipped with a sensor configured to monitor the environment in front of the vehicle in real time to obtain information about the condition of the road and its surface. Thanks to its high resolution and high-speed processing, the preview camera 113 can detect even the smallest features such as irregularities, obstacles, potholes, and sudden elevation changes on the road.

[0043] The LiDAR 114 may be a sensor configured to measure distances and shapes in the vehicle's surroundings by transmitting high-speed laser pulses and detecting their reflection. The data output by the LiDAR may, for example, be expressed as a 3D point cloud of the surroundings, which can be used to determine the shape, size, and location of objects, as well as the height and condition of the road surface.

[0044] The preview camera 113 and the LiDAR 114 are examples of sensors for inputting or capturing information about the environment in front of the vehicle. However, the present disclosure is not limited thereto, and any sensor capable of capturing the environment in front of the vehicle, such as a high-resolution camera, a radar, an inertial measurement unit (IMU), a global positioning system (GPS), a ToF camera, a thermal imaging camera, and a stereo camera, may be used as appropriate.

[0045] The HD map 115 may be a high-resolution digital map that provides more detailed and accurate information than a typical navigation map. However, in some embodiments of the present disclosure, the typical navigation map may also be used. The HD map 115 may be used primarily for autonomous vehicles and enables the vehicles to accurately perceive the surroundings and drive safely. The HD map 115 may be created based on data collected by various sensors, such as preview cameras, LiDARs, and RADARs. The HD map 115 may include detailed information about the road gradient, the location of lanes, traffic signals, road signs, the structure of intersections, etc., and the information on the map may be updated in real time, for example, but not exclusively, through vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication.

[0046] Information about the profile of the road surface obtained from the preview camera 113, the LiDAR 114, the HD map 115, etc., may be provided to a second frequency decoder 122 and may include information about the future of the input load from a time perspective.

[0047] The frequency decoder 120 may include the first frequency decoder 121 configured to process data input or received from the wheel G sensor 111 and the height sensor 112, and the second frequency decoder 122 configured to process data input or received from the preview camera 113, the LiDAR 114, and the HD map 115. The data input or received by the first frequency decoder 121 may include information about a current input load, and the data input or received by the second frequency decoder 122 may include information about the state of future driving, e.g., the profile of the road surface in front of a vehicle.

[0048] The data input or received by the wheel G sensor 111 and the height sensor 112 can be measured in real time during the travel of a vehicle and expressed as an input load received by a suspension system. As shown in Fig. For example, as shown in Figure 2, when a vehicle travels on the road surface with its tread, the movement of "B" (e.g., a spring) can be detected and divided by time to obtain the velocity, and it can be detected and differentiated with time to obtain desired physical quantities such as acceleration. Regardless of whether the load is measured from "A" (e.g., a vehicle body), "B," or "C" (e.g., a damper), the input load can be calculated based on the correlation.

[0049] The calculated input load may be time-domain data, and the input load signal may be decomposed or converted into frequency components by the frequency decoder 120 based on the fast Fourier transform (FFT). As described above, the frequency decoder 120 may include the first frequency decoder 121 and the second frequency decoder 122. The first frequency decoder 121 may process or express data input from the wheel G sensor 111 and the height sensor 112 as frequency components, and the second frequency decoder 122 may process or express data input from the preview camera 113, the LiDAR 114, and the HD card 115 as frequency components through the fast Fourier transform. When an input load is expressed as a frequency component, it may be expressed as a combination of multiple frequency components. As shown in Fig. As shown in Figure 4, the input load can be expressed as f1, f2, f3, f4, and f5, for example. Depending on each frequency component, i.e., f1, f2, f3, f4, and f5, it can be determined which actuator needs to be controlled from a plurality of actuators in a suspension system. The process of controlling an actuator of each frequency is described below.

[0050] The MCU 130 may be an electronic device configured to control and manage various functions of a vehicle. The MCU 130 may include, for example, but not exclusively, one or more integrated memories, an input / output port, a timer, an interrupt, and an integrated circuit with various communication functions. The MCU 130 may process various data input from sensors (e.g., a speed sensor, a temperature sensor, a fuel level sensor, etc.). In general, the MCU 130 may control the functions of output devices, such as an engine control system, a braking system, lighting, and an air conditioning system, and may serve as a communication network between various devices or components in a vehicle, based on or using an internal communication network, such as aa Controller Area Network (CAN) or a Local Interconnect Network (LIN). Furthermore, the MCU 130 may monitor the status and performance of a vehicle and be configured to alert the driver of the vehicle when a problem occurs. Furthermore, the MCU 130 may be configured to update and manage software and manage or control the vehicle's battery and fuel. According to one embodiment of the present disclosure, the MCU 130 may process the data transmitted from the frequency decoder 120 and transmit the processed data to the ECU 140.

[0051] In particular, the MCU 130 can compare the resulting value of controlling an actuator based on an input target ride comfort with the resulting measured value of the frequency decoder 120 and generate control values ​​for each actuator to meet a predetermined target value. For example, the MCU 130 can control the actuators of a suspension system based on an input target ride comfort value and convert the resulting value into a "target function." The target function is a function for achieving a specific goal, and the difference or ratio between a target ride comfort and an actual ride comfort can be determined according to the target function. The MCU 130 can calculate the difference between a target function (e.g.,a desired result or state) and an actual movement of an actuator and generate a control value for a new actuator to minimize or eliminate the difference between the objective function and the actual movement of the actuator.

[0052] For example, the ECU 140 may be a microcomputer that controls a vehicle's electronic system and can manage and optimize the operation of an engine, the control of a transmission, a braking system, a stability system, lighting, an air conditioning system, communication, and the interaction between various sensors and actuators. The ECU 140 may include software and hardware necessary to control at least one of several functions of a vehicle. Fig. 1, the ECU 140 may receive one or more control values ​​for each actuator from the MCU 130 and transmit a control signal to the actuator for controlling an actuator. According to certain embodiments of the present disclosure, the MCU 130 and the ECU 140 are depicted as separate features, as shown in Fig. 1, but the MCU 130 and the ECU 140 may be implemented as an integrated circuit or chip or in various forms according to design changes or needs by a person of ordinary skill in the art.

[0053] The actuators 150-1, 150-2, ..., 150-n are integrated into the suspension system. The suspension system may include one or more spring units, a damper unit, a vibration isolator unit, etc., as shown in Fig. 3, which is described below, but is not limited thereto. The spring unit may, for example, include a coil spring or an air spring used in the suspension system, and the spring unit may be designed so that the tension and elasticity of the coil spring or air spring can be adjusted by adjusting an actuator. For example, the stroke of a coil spring may be controlled by a stroke function, and an air spring may be controlled by the pump output and compressibility of a fluid.

[0054] The damper unit belonging to the suspension system can dynamically control the reaction force of a damper. The suspension system, which includes the damper unit, can adjust the damping pressure or spring tension by controlling a valve based on the condition of the irregular road surface in order to control ride comfort. In addition to the spring unit and the damper unit, other devices may be included. For example, a vibration isolator unit or isolator configured to absorb and dissipate vibrations and shocks may also be included. Vibration isolator units or isolators can be divided or categorized into passive vibration isolator units or isolators and active vibration isolator units or isolators. The passive vibration isolator unit or isolator may be a device or isolator thatwhich is designed to absorb vibrations and shocks using elastic materials such as rubber or polyurethane. The active vibration isolator unit or isolator can work in conjunction with or in combination with an actuator to perform active vibration isolation based on control signals corresponding to different vibration types. The active vibration isolator or isolator can be controlled by the properties of variable materials.

[0055] Fig. 2 is a spider web diagram showing ride comfort expressed in multiple characteristics according to an embodiment of the present disclosure.

[0056] Ride quality is a term that encompasses the comfort, stability, responsiveness, etc. in a moving vehicle and can also refer to the experiences of drivers and passengers under various operating conditions of the vehicle. Ride comfort can be influenced by various factors, such as the performance of the vehicle's suspension, interior noise, vibration, wind noise, and seat comfort. Since ride comfort is a highly subjective experience, it can feel different depending on individual experience or expectation. However, when developing and tuning a vehicle, it is necessary to objectively evaluate and standardize ride comfort. Ride comfort can, for example, be expressed with several key figures or specified with several factors using a spider web, as in Fig. 2 shown.

[0057] In Fig. 2, a characteristic or indicator (A) corresponds to the primary driving behavior and is a characteristic element that indicates the level of overall stability and perceived comfort in a vehicle and is an indicator of the vehicle's steering ability and harmony. A well-coordinated vehicle reacts predictably even during sudden movements and conveys a sense of balance within the vehicle to the driver and passengers.

[0058] One parameter or indicator (B) corresponds to shock harshness / hardness. It is a characteristic element that indicates the degree of shock harshness and hardness, indicating how strong a shock impacts the suspension system when the vehicle is moving or driving over uneven road surfaces such as potholes or speed bumps. A well-designed suspension system can effectively absorb these shocks and provide a comfortable ride for the driver and passengers.

[0059] A characteristic value or indicator (C) corresponds to unsettled handling and is a characteristic element that indicates the degree of a vehicle's reaction to small road irregularities, indicating the level of small vibrations and brief side-to-side roll. If the vehicle reacts too violently to these, the driver and passengers may feel uncomfortable while driving.

[0060] One parameter or indicator (D) corresponds to the vibration level, which is a characteristic element that indicates the degree of vibration of a vehicle and / or the degree of displacement of the vehicle in the direction of travel. The shocks and vibrations that occur while driving on the road are transmitted to the vehicle's interior.

[0061] A characteristic value or indicator (E) corresponds to suspension noise and is a characteristic element that indicates the noise level, such as a hissing noise generated by a suspension. Such noise can impair ride comfort, and excessive noise can reduce comfort in a vehicle.

[0062] A characteristic value or rating (F) corresponds to steering feel and is a characteristic element that indicates the driver's perceived responsiveness when the vehicle changes direction. It is closely related to steering feel and ride comfort. The characteristic value (F) indicates whether excessive force is required when changing the vehicle's direction, how well the steering center is maintained when the steering is not turned, and whether the steering does not move the vehicle excessively when turned slightly. Predictable and precise steering feel can give the driver confidence.

[0063] A characteristic value or rating (G) corresponds to yaw response and damping, and refers to the extent of a vehicle's left and right turning motion. Response and damping indicate how quickly and smoothly the vehicle's left and right turning movements are controlled. If yaw is delayed or responds slowly, straight-line driving behavior may deteriorate.

[0064] A characteristic value or indication (H) corresponds to the linearity of the steering and is a characteristic element that indicates the degree of correspondence between the steering input and the vehicle's response. When the steering is linear, the driver can predict the vehicle's responses to steering inputs.

[0065] A characteristic value or rating (I) corresponds to roll stability and refers to the stability of a vehicle when cornering. Excessive roll can cause the vehicle to feel unstable.

[0066] The characteristic values ​​(A) to (I) in Fig. 2 correspond to various representative factors that determine ride comfort. The values ​​corresponding to each characteristic can be expressed in a spider web diagram as data measured by a specific test or sensor, or as evaluation points according to a specific standard. Using such a diagram, the general characteristics of a vehicle's ride comfort and the performance related to each factor can be grasped at a glance, and comparisons can be made between vehicle types or between vehicles in different tuning states and ride quality can be analyzed. The target ride comfort may change depending on the intended use or driving style of a vehicle and the strategy of the vehicle manufacturer and can be expressed in numbers or figures by a combination of the characteristic values ​​(A) to (I) in Fig. 2 can be expressed.

[0067] To tune or optimize a vehicle's ride comfort, it may be necessary to control the movement and operation of various actuators, such as functional elements (e.g., a spring unit, a damper unit, a vibration isolation unit or isolator, an electronic control unit, etc.). Since each of these actuators can operate independently or in conjunction with each other, the overall ride comfort can be determined.

[0068] A smooth ride means minimizing the vehicle's response to road irregularities or bumps, allowing passengers to enjoy a stable and comfortable ride. By controlling the stroke of a spring to match the characteristics of the opposite satellite of an input signal, bumps or irregularities in the road can be neutralized. Dampers can be used to reduce shocks or vibrations. By reversing the phase, a damper can move in the opposite direction to the movement of a spring, thereby reducing unnecessary vibrations or movement. To ensure a smooth ride, for example, the spring unit can be controlled at 80% and the damper unit at 20%. In other words, it may be possible to control signals in a low frequency band (Hz).Signals in the low frequency band (Hz) can be an indicator for evaluating a vehicle's vibrations or responsiveness. The low frequency band (Hz) can generally correspond to strong vibrations or shocks, and it may be possible to improve vehicle stability by effectively controlling or managing them.

[0069] For a smooth ride, the spring rate and damping force can be lowered to absorb maximum shock. For example, the spring unit can be controlled by 20% and the damper unit by 80%. In other words, signals in a mid-frequency band (Hz) can be controlled. Signals in the mid-frequency band (Hz) typically indicate moderate road irregularities or bumps. By controlling signals in the mid-frequency band (Hz), a vehicle's responsiveness can be controlled and a smooth ride can be ensured.

[0070] In order to achieve the smooth ride and the smooth ride, the degree of control of the spring unit and the damper unit can be determined based on the ride comfort characteristics described above, and the degree of control can be changed in various ways according to the needs.

[0071] The spring unit may primarily control the low frequency band (Hz). In an example where the spring unit comprises coil springs, only the stroke may be controlled, and in an example where the spring unit comprises air springs, additional variables such as pump capacity and / or speed and the compressibility of a fluid may be taken into account. For the damper unit, the entire frequency band (Hz) may be subject to control, and the range to be controlled may expand depending on the characteristics of a valve, and the damper unit may include, for example, electronically controlled dampers. For the vibration isolator unit or isolator, the high frequency band (Hz) may be subject to control. The vibration isolator unit or isolator may comprise a passive vibration isolator unit or isolator and / or an active vibration isolator unit or isolator.The passive vibration isolator unit or passive isolator can be a device designed to absorb vibrations and shocks using elastic materials such as rubber or polyurethane. The active vibration isolator unit or active isolator can operate in conjunction with or in combination with an actuator and perform the vibration isolation process based on control signals corresponding to different vibration types. The active vibration isolator or isolator can be controlled by the properties of variable materials.

[0072] When an active suspension is used as a suspension system, it may be possible to actively control the height and damping force of a vehicle using control signals. For example, the ECU 140 in Fig. 1 transmit a control signal to the active suspension to control the actuators of the active suspension separately.

[0073] Next, a method for controlling the spring unit, the damper unit and the vibration isolating unit or isolator based on the frequency resolved by the frequency decoder 120 with reference to the Fig. 3 and Fig. 4 described.

[0074] Fig. Figure 3 is a schematic view showing the profile of a road surface and a suspension system according to an embodiment of the present disclosure. The road surface profile may refer to the results of measuring irregularities, defects, and height differences on the road surface, factors that affect the ride comfort of a vehicle.

[0075] Referring to Fig. 3, an input load received by or applied to the suspension system may be determined by a vehicle body A, a spring unit B, a damper unit C, and a vibration isolation unit or isolator D. In Fig. 3 denotes m s a sprung mass, m u an unsprung mass, C s a damper damping coefficient and k t a spring constant of a tire.

[0076] The input load measured by the input sensors can be expressed in the time domain as shown in the diagram in Fig. 4. The signal of the measured input load in the time domain can be converted by the fast Fourier transform (FFT) so that it can be decomposed into frequencies such as f1, f2, f3, f4 and f5.

[0077] For example, if the frequency detected by the frequency decoder 120 is in a range of 0 Hz to 5 Hz, the spring unit can be controlled by 80%, the damper unit by 20%, and the vibration isolation unit or isolator by 0%. The frequency in a range of 0 Hz to 5 Hz can mainly control the spring unit. For another example, if the frequency is in a range of 3 Hz to 25 Hz, the spring unit can be controlled by 10%, the damper unit by 60%, and the vibration isolation unit or isolator by 30%. The frequency in a range of 3 Hz to 25 Hz can control the entire spring unit, the damper unit, and the vibration isolation unit or isolator to ensure the desired ride comfort.As another example, when the frequency falls within a range of 20 Hz or more, preferably within a range of 20 Hz to 250 Hz, the spring unit can be controlled by 0%, the damper unit by 30%, and the vibration isolation unit or isolator by 70%. The frequency in the range of 20 Hz or more can mainly control the damper unit and the vibration isolation unit or isolator.

[0078] The spring unit, the damper unit, and the vibration isolator unit or isolator are controlled according to the respective frequency component to control the ride comfort of the vehicle. The spring unit, the damper unit, and the vibration isolator unit or isolator can be controlled for each frequency to control the ride comfort of the vehicle. A monitored vehicle can recalculate the input load, decompose the calculated input load into frequencies, and control the actuators again based on the decomposed frequencies. This process can be repeated until the calculated ride comfort reaches a target value. According to an embodiment of the present disclosure, the spring unit, the damper unit, or the vibration isolator unit or isolator canThe isolator can be controlled simultaneously in a frequency-dependent manner, so that the duplication of work that occurs when tuning actuators according to the conventional development sequence can be avoided.

[0079] Fig. 5 is a flowchart illustrating a method for controlling an actuator to improve ride comfort and steering stability of a vehicle according to an embodiment of the present disclosure.

[0080] In step S510, an input load received by or acting on a suspension system of the vehicle (e.g., input loads measured by sensors mounted at various locations on the suspension system) may be calculated. Here, the suspension system may include at least a spring unit, a damper unit, and a vibration isolation unit or isolator.

[0081] To calculate the input load, one or more sensors can detect the displacement or movement of at least one of the vehicle body, spring unit, and damper unit when the vehicle travels on the road surface with its profile. In addition, to calculate the input load, the road surface profile can be input via a sensor for inputting information about the front of the vehicle or a high-resolution (HD) map. Here, the road surface profile can refer to the results of measuring or detecting bumps, defects, and height differences on the road surface, which affect ride comfort during driving. Such a profile can be used as an important indicator in the evaluation of wear, damage, service life, etc.the road and in particular serve as important reference factors or materials in the design of a vehicle suspension or the repair of roads.

[0082] In step S520, the input load can be decomposed for each frequency. The frequencies can include at least a first frequency in a first frequency band, a second frequency in a second frequency band, and a third frequency in a third frequency band. For example, the first frequency can be in a range from 0 Hz to 5 Hz, the second frequency in a range from 3 Hz to 25 Hz, and the third frequency in a range from 20 Hz to 250 Hz.

[0083] In step S530, a corresponding control signal may be generated for each frequency to control the spring unit and / or the damper unit and / or the vibration isolation unit or isolator in the suspension system.

[0084] In step S540, a corresponding control signal generated for each frequency may be applied to the spring unit and / or the damper unit and / or the vibration isolation unit or the isolator in the suspension system to control the spring unit, the damper unit and / or the vibration isolation unit or the isolator. The spring unit may be, for example, a coil spring or an air spring. The coil spring may be controlled such that only the stroke is controlled by a stroke function at the first frequency, the air spring may be controlled by the pump output and the compressibility of a fluid at the first frequency, the damper unit may be controlled according to the properties of a valve as a function of speed at the second frequency, and the vibration isolation unit or the isolator may be controlled by the properties of variable materials at the third frequency.

[0085] Fig. 6 is a flowchart illustrating a method of controlling an actuator to improve ride comfort and steering stability of a vehicle according to another embodiment of the present disclosure.

[0086] In step S610, a target driving quality expressed in several parameters can be determined. The desired driving comfort can be changed or adjusted depending on the intended use or driving style of a vehicle and the vehicle manufacturer's strategy. The desired driving comfort can be determined, for example, by a combination of the parameters (A) to (I) in Fig. 2 can be expressed.

[0087] In step S620, an input load received by or applied to the vehicle's suspension (e.g., input loads measured by sensors mounted at various locations on the suspension) may be calculated. Here, the suspension system may include a spring unit and / or a damper unit and / or a vibration isolation unit or isolator. To calculate the input load, one or more sensors may detect the displacement or movement of the vehicle body and / or the spring unit and / or the damper unit as the vehicle passes over the road surface with its profile. In addition, to calculate the input load, the road surface profile may be input via a sensor for inputting information about the vehicle front or a high-resolution (HD) map.

[0088] In step S630, the input load can be decomposed for each frequency. The frequencies can include at least a first frequency in a first frequency band, a second frequency in a second frequency band, and a third frequency in a third frequency band. For example, the first frequency can be in a range from 0 Hz to 5 Hz, the second frequency in a range from 3 Hz to 25 Hz, and the third frequency in a range from 20 Hz to 250 Hz.

[0089] In step S640, a corresponding control signal may be generated for each frequency to control at least one of the spring units, the damper unit, and the vibration isolation unit or isolator in the suspension system.

[0090] In step S650, a respective control signal generated for each frequency may be applied to at least one of the spring unit, the damper unit, and the vibration isolating unit included in the suspension system to control at least one of the spring unit, the damper unit, and the vibration isolating unit or isolator. The spring unit may be, for example, a coil spring or an air spring. The coil spring may be controlled such that only the stroke is controlled by a stroke function at the first frequency, the air spring may be controlled by the pump output and the compressibility of a fluid at the first frequency, the damper unit may be controlled according to the properties of a valve as a function of speed at the second frequency, and the vibration isolating unit or isolator may be controlled by the properties of variable materials at the third frequency.

[0091] In step S660, it may be determined whether the target driving quality set in step S610 is met in response to the control signal generated in step S650. If the target driving quality set in step S610 is met, control of the actuators may be terminated, and if the target driving quality set in step S610 is not met, steps S620 to S650 may be repeated until the target driving quality set in step S610 is met.

[0092] The device described above may be formed from hardware components, software components, and / or a combination of hardware and software components. For example, the devices and components described in the embodiments of the present disclosure may be formed using one or more general-purpose or special-purpose computers, such as a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field-programmable gate array (FPGA), a programmable logic unit (PLU), a microprocessor, or any other device capable of executing instructions and responding. The processing unit may execute an operating system (OS) and one or more software applications running on the OS.Furthermore, the processing unit may access, store, manipulate, process, and generate data in response to the execution of the software. For simplicity, in some cases, a single processing unit is described as being used, but a person of ordinary skill in the art will understand that such a processing unit may include multiple processing elements and / or multiple types of processing elements. The processing unit may, for example, include multiple processors or a processor and a control unit. In addition, other processing functions, such as parallel processors, may also be provided.

[0093] Although the limited embodiments and drawings have been described above, a person of ordinary skill in the art may make various changes and variations to the above description. For example, if the described techniques are performed in a different order than in the described method, or if the described components, such as a system, structure, device, and circuit, are combined in a different form than in the described method, or if other components or equivalents are substituted, adequate results may be achieved.

[0094] Therefore, other embodiments and equivalents of the claims are also within the scope of the claims described below. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] KR 10-2023-0143754

[0001] KR 10-2395275

[0004] KR 10-0593416

[0004]

Claims

[1] A method for controlling an actuator (150-1, 150-2, ..., 150-n) in a vehicle, the method comprising: Calculating an input load (S510) received from a suspension system comprising a spring unit (B) and / or a damper unit (C) and / or a vibration isolator (D); Decomposing the calculated input load (S520) received from the suspension system for each of the frequencies by a frequency decoder (120, 121, 122); Generating control signals (S530) for each of the frequencies based on the input load decomposed for each of the frequencies to control the spring unit (B) and / or the damper unit (C) and / or the vibration isolator (D) included in the suspension system; and Applying the control signals (S540) generated for each of the frequencies to the spring unit (B) and / or the damper unit (C) and / or the vibration isolator (D) included in the suspension system to control the spring unit (B) and / or the damper unit (C) and / or the vibration isolator (D). [2] The method according to claim 1, wherein calculating the input load (S510) comprises calculating a profile of a road surface by detecting the movement of a vehicle body (A) and / or the spring unit (B) and / or the damper unit (C) using one or more sensors (111, 112) when the vehicle travels on the road surface. [3] The method according to claim 1 or 2, wherein calculating the input load (S510) comprises calculating the input load by receiving a profile of a road surface from one or more sensors (113, 114) for inputting information about a front area of ​​the vehicle or a high-definition (HD) map (115). [4] A method according to any one of claims 1 to 3, wherein the frequencies comprise a first frequency in a range of 0 Hz to 5 Hz, a second frequency in a range of 3 Hz to 25 Hz and a third frequency in a range of 20 Hz to 250 Hz. [5] The method of claim 4, wherein: the spring unit (B) includes: a coil spring configured to be controlled such that a stroke is controlled by a stroke function at the first frequency; or an air spring configured to be controlled by a pump capacity and a compressibility of a fluid at the first frequency, and wherein the damper unit (C) is arranged to be controlled according to the properties of a valve as a speed function in the second frequency, and the vibration isolator (D) is arranged to be controlled by properties of variable materials in the third frequency. [6] A method for controlling an actuator (150-1, 150-2, ..., 150-n) in a vehicle, the method comprising: Setting a target driving behavior (S610), expressed in several parameters; Calculating an input load (S620) received from a suspension system comprising a spring unit (B) and / or a damper unit (C) and / or a vibration isolator (D); Decomposing the calculated input load (S630) received from the suspension system for each of the frequencies by a frequency decoder (120, 121, 122); Generating control signals (S640) for each of the frequencies based on the input load decomposed for each of the frequencies to control the spring unit (B) and / or the damper unit (C) and / or the vibration isolator (D) included in the suspension system; Applying the control signals (S650) generated for each of the frequencies to the spring unit (B) and / or the damper unit (C) and / or the vibration isolator (D) included in the suspension system to control the spring unit (B) and / or the damper unit (C) and / or the vibration isolator (D), and Determine whether the specified target driving behavior is satisfied depending on the control signals (S660). [7] The method according to claim 6, wherein calculating the input load (S620) comprises calculating a profile of a road surface by detecting the movement of a vehicle body (A) and / or the spring unit (B) and / or the damper unit (C) using one or more sensors (111, 112) when the vehicle travels on the road surface. [8] The method of claim 6 or 7, wherein calculating the input load (S510, S620) comprises calculating the input load by receiving a profile of a road surface from one or more sensors (113, 114) arranged to measure in front of the vehicle. [9] The method according to any one of claims 6 to 8, wherein calculating the input load (S510, S620) comprises calculating the input load by receiving a profile of a road surface from a high-resolution (HD) map (115). [10] A method according to any one of claims 6 to 9, wherein the frequencies comprise a first frequency in a first frequency band, a second frequency in a second frequency band and a third frequency in a third frequency band. [11] The method of claim 10, wherein: the spring unit (B) includes: a coil spring configured to be controlled such that a stroke is controlled by a stroke function at the first frequency; or an air spring configured to be controlled by a pump capacity and a compressibility of a fluid at the first frequency, and wherein the damper unit (C) is arranged to be controlled according to the properties of a valve as a speed function in the second frequency, and the vibration isolator (D) is arranged to be controlled by properties of variable materials in the third frequency. [12] A method according to claim 10 or 11, wherein the first frequency is in a range of 0 Hz to 5 Hz, the second frequency is in a range of 3 Hz to 25 Hz and the third frequency is in a range of 20 Hz to 250 Hz. [13] The method of any one of claims 6 to 12, wherein the plurality of characteristics comprises a combination of two or more characteristic elements of primary handling, bump roughness / harshness, choppy handling, judder, suspension noise, steering feel, yaw and damping, steering linearity, and roll stability. [14] Device (100) for controlling an actuator (150-1, 150-2, ..., 150-n) in a vehicle, the device comprising: a suspension system comprising a spring unit (B) and / or a damper unit (C) and / or a vibration isolator (D); a frequency decoder (120, 121, 122) configured to decompose an input load of the suspension system measured by one or more sensors for each of the frequencies by the fast Fourier transform (FFT); a microcontroller unit (MCU) (130) configured to generate a control value for an actuator (150-1, 150-2, ..., 150-n) configured to control the spring unit (B) and / or the damper unit (C) and / or the vibration isolator (D) included in the suspension system on the basis of a target ride comfort expressed in a plurality of characteristic values; and an electronic control unit (ECU) (140) configured to receive the control value for the actuator (150-1, 150-2, ..., 150-n) from the MCU (130) in order to receive a signal for controlling the spring unit (B) and / or the damper unit (C) and / or the vibration isolator (D). [15] The device (100) according to claim 14, wherein the MCU (130) is configured to calculate a difference between a resultant value of the control of the spring unit (B) and / or the damper unit (C) and / or the vibration isolator (D) based on the target ride comfort and a state value indicating a current state of the vehicle, and to update the control value for the actuator (150-1, 150-2, ..., 150-n) to meet a predetermined target value. [16] The device (100) according to claim 14 or 15, wherein the input load is calculated by detecting the movement of a vehicle body (A) and / or the spring unit (B) and / or the damper unit (C) using one or more sensors (111, 112) when the vehicle is traveling on a road surface. [17] The apparatus (100) of any one of claims 14 to 16, wherein the input load is calculated by receiving a profile of a road surface from one or more sensors (113, 114) for inputting information about a front area of ​​the vehicle or a high-resolution (HD) map (115). [18] The device (100) of claim 15, wherein the frequencies comprise a first frequency in a first frequency band, a second frequency in a second frequency band, and a third frequency in a third frequency band. [19] Device (100) according to claim 18, wherein: the spring unit (B) includes: a coil spring configured to be controlled such that a stroke is controlled by a stroke function at the first frequency; or an air spring configured to be controlled by a pump capacity and a compressibility of a fluid at the first frequency, and wherein the damper unit (C) is arranged to be controlled according to the properties of a valve as a speed function in the second frequency, and the vibration isolator (D) is arranged to be controlled by properties of variable materials in the third frequency. [20] The device (100) of claim 18 or 19, wherein the first frequency is in a range of 0 Hz to 5 Hz, the second frequency is in a range of 3 Hz to 25 Hz, and the third frequency is in a range of 20 Hz to 250 Hz.

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