Centrifugal force active compensation control algorithm and vibration isolation system for car seat

Abstract

The application provides a centrifugal force active compensation control algorithm and a vibration isolation system for a car seat, comprising the following steps: a compensation angle calculation step: based on vehicle chassis speed information, acceleration information and angular velocity information, the expected real-time centrifugal force compensation angle during vehicle sharp cornering is calculated through a sensor fusion algorithm; a trajectory planning step: according to the maximum centrifugal force compensation angle, the trajectory during the rebound of the seat body after the vehicle passes the corner is planned; a PI control step: according to the real-time centrifugal force compensation angle and the trajectory planning result, the angle of the damping motor is adjusted, so that the damping motor can follow the expected centrifugal force compensation angle in real time. The application can calculate the centrifugal force compensation angle, and then realize better centrifugal force compensation function for the seat body through the damping motor.

Description

Technical Field

[0001] This invention relates to the field of vehicle vibration reduction technology, specifically to an active compensation control algorithm for centrifugal force of automobile seats and a vibration isolation system. Background Technology

[0002] In applications involving the transport of precision instruments, blood, and passengers, the transported goods are often adversely affected by the vehicle's sharp turns and jolting. While the vehicle's suspension system can mitigate the impact of uneven road surfaces, there is currently a lack of in-depth research on how to overcome the adverse effects of sharp turns. Furthermore, during sharp turns, passengers may experience a "throw-out" sensation due to inertia, and in emergencies, they may even hit the doors and suffer injuries. Therefore, in many scenarios, eliminating the adverse effects of vehicle inertia on the transported goods is crucial. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the purpose of this invention is to provide an active compensation control algorithm for centrifugal force in automotive seats and a vibration isolation system.

[0004] The present invention provides an active compensation control algorithm for centrifugal force of automobile seats, comprising the following steps:

[0005] Compensation angle calculation steps: Based on the vehicle chassis speed information, acceleration information and angular velocity information, the desired real-time centrifugal force compensation angle when the vehicle makes a sharp turn is calculated through a sensor fusion algorithm;

[0006] Trajectory planning steps: Based on the maximum compensation angle of centrifugal force, plan the trajectory of the seat body during the rebound process after the vehicle has cornered;

[0007] PI control steps: Based on the real-time centrifugal force compensation angle and trajectory planning results, adjust the angle of the vibration damping motor so that the vibration damping motor keeps up with the desired centrifugal force compensation angle in real time.

[0008] Preferably, the compensation angle calculation step specifically includes the following steps:

[0009] Step a1: Obtain the vehicle's lateral acceleration, normal angular velocity, and velocity information in inertial space;

[0010] Step a2: Filter the high-frequency noise in the information obtained in step a1, and normalize the filtered information to obtain a normalized value.

[0011] Step a3: Obtain the expected centrifugal force compensation angle of the vibration damping motor based on the normalized value in step a2, the mapping relationship between vehicle speed and centrifugal force compensation angle.

[0012] Preferably, in step a2, the high-frequency noise of the acquired information is filtered by an FIR digital filter, and the filtered information is normalized by a fusion algorithm.

[0013] Preferably, in step a3, the mapping relationship is a mapping model based on a wavelet neural network;

[0014] The wavelet neural network model is set as a three-layer network, consisting of an input layer, a hidden layer, and an output layer.

[0015] The neural network has 3 input layer nodes, namely vehicle speed x1, normalized value x2, and error feedback value x3; 4 hidden layer nodes; and 1 output layer node, which is the centrifugal force compensation angle.

[0016] The output formula of the wavelet neural network model is:

[0017]

[0018] Among them, a j and b j These are the scaling and translation factors of the wavelet basis functions, w, respectively. ij Let w be the weights from the i-th node in the input layer to the j-th node in the hidden layer. j y is the weight from the j-th node of the hidden layer to the output layer, and y is the centrifugal force compensation angle.

[0019] Preferably, in step a3, when the absolute value of the normalized value is greater than a preset threshold, the centrifugal force compensation angle of the vibration damping motor is calculated; when the absolute value of the normalized value is less than or equal to the preset threshold, the centrifugal force compensation angle of the vibration damping motor is not calculated.

[0020] Preferably, the trajectory planning step specifically involves: obtaining the maximum rotation angle of the seat body during the centrifugal force compensation stage, using the maximum rotation angle as the starting point and zero angle as the ending point, and performing trajectory planning within a preset time.

[0021] Preferably, the PI control step specifically involves: tracking the angle of the vibration damping motor, using the position information of the motor encoder as a feedback signal, and adjusting the proportional-integral parameters to make the vibration damping motor keep up with the desired centrifugal force compensation angle in real time.

[0022] Preferably, it also includes a turning type detection step, specifically: detecting the turning type of the vehicle, including general turns, continuous turns and S-turns;

[0023] A regular turn is a turn within 90 degrees, a continuous turn is a turn in the same direction within 3 seconds, and an S-turn is a turn in different directions within 3 seconds.

[0024] Preferably, during continuous turns, the normalized value calculated by the compensation angle calculation step has the same sign within a preset time.

[0025] When making an S-turn, the normalized value calculated by the compensation angle calculation step will have its sign reversed within a preset time.

[0026] During a normal turn, the normalized value calculated by the compensation angle calculation step appears only once within a preset time.

[0027] The present invention also provides an automotive seat vibration isolation system, which adopts the above-mentioned automotive seat centrifugal force active compensation control algorithm, including: control components, vibration damping motor, scissor mechanism and air spring;

[0028] The scissor lift mechanism is rotatably mounted on the vehicle chassis, and the seat body is connected to the vehicle chassis via the scissor lift mechanism. The vibration damping motor drives the scissor lift mechanism to rotate.

[0029] The air spring is mounted on the scissor mechanism and is used to buffer the compression of the scissor mechanism between the vehicle chassis and the seat body.

[0030] The control component is electrically connected to the vibration damping motor, and the control component is used to adjust the rotation of the vibration damping motor.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. This invention has the function of vehicle centrifugal force compensation under various complex road conditions. The sensor fusion perception algorithm integrates the acceleration, angular velocity and speed information of the vehicle chassis, and calculates the compensation angle required under different turning radii and curvatures in real time, which has a wide range of applications.

[0033] 2. The centrifugal force compensation motion control algorithm of the present invention has strong anti-interference ability, stable and reliable tracking accuracy and response speed under different loads, and has load adaptability. The slow rebound function after the vehicle turns has the function of reducing impact and improving ride comfort.

[0034] 3. In the passive vibration isolation system of the present invention, the scissor mechanism is combined with an air spring. When there is high-frequency vertical vibration, the air spring will play a passive vibration isolation role, thereby reducing the impact of high-frequency vertical vibration on ride comfort. Attached Figure Description

[0035] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0036] Figure 1 This is a schematic diagram of the structure of an automotive vibration isolation system device in one embodiment;

[0037] Figure 2 for Figure 1 A magnified view of a portion of the image;

[0038] Figure 3 A schematic diagram illustrating the principle of obtaining the desired angle for centrifugal force compensation;

[0039] Figure 4 This is a schematic diagram illustrating the principle of centrifugal force compensation motion control method;

[0040] Figure 5 This is a schematic diagram illustrating the principle of the mapping relationship.

[0041] The diagram shows:

[0042] Inertial Measurement Unit 1, Scissor Mechanism 6

[0043] Controller 2, Air Spring 7

[0044] Motor driver 3 Rotary bearing 8

[0045] 4 vibration damping motors, 9 seat bodies

[0046] Reducer 5, Vehicle chassis 10 Detailed Implementation

[0047] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0048] Example 1:

[0049] like Figures 1-5 As shown, this embodiment provides an active compensation control algorithm for centrifugal force of automotive seats, including the following steps:

[0050] Compensation angle calculation steps: Based on vehicle chassis speed, acceleration, and angular velocity information, the desired real-time centrifugal force compensation angle during sharp turns is calculated using a sensor fusion algorithm. The specific steps include the following:

[0051] Step a1: Obtain the vehicle's lateral acceleration, normal angular velocity, and velocity information in inertial space;

[0052] Step a2: Filter the high-frequency noise in the information obtained in step a1, normalize the filtered information to obtain a normalized value; filter the high-frequency noise in the obtained information using an FIR digital filter; normalize the filtered information using a fusion algorithm.

[0053] Step a3: Obtain the expected centrifugal force compensation angle of the vibration damping motor based on the normalized value, the mapping relationship between vehicle speed and centrifugal force compensation angle in step a2; when the absolute value of the normalized value is greater than the preset threshold, calculate the centrifugal force compensation angle of the vibration damping motor, the preset threshold is 0.1; when the absolute value of the normalized value is less than or equal to the preset threshold, do not calculate the centrifugal force compensation angle of the vibration damping motor, the preset threshold is 0.1.

[0054] In step a3, the mapping relationship is a mapping model based on wavelet neural networks, such as... Figure 5 As shown, the wavelet neural network model is set as a three-layer network, consisting of an input layer, a hidden layer, and an output layer, to ensure the real-time performance of the control process. The input layer of the neural network has 3 nodes, namely the vehicle speed x1, the normalized value x2, and the error feedback value x3. The hidden layer of the neural network has 4 nodes, and the output layer of the neural network has 1 node, which is the centrifugal force compensation angle. The output formula of the wavelet neural network model is:

[0055]

[0056] Among them, a j and b j These are the scaling and translation factors of the wavelet basis functions, w, respectively. ij Let w be the weights from the i-th node in the input layer to the j-th node in the hidden layer. j y is the weight from the j-th node of the hidden layer to the output layer, and y is the centrifugal force compensation angle.

[0057] Trajectory planning steps: Based on the maximum centrifugal force compensation angle, the trajectory of the seat body during the rebound process after the vehicle turns is planned; the specific trajectory planning steps are: obtain the maximum turning angle of the seat body during the centrifugal force compensation stage, take the maximum turning angle as the starting point and zero angle as the ending point, and perform trajectory planning within a preset time, which is 3 to 4 seconds.

[0058] PI control steps: Based on the real-time centrifugal force compensation angle and trajectory planning results, the angle of the vibration damping motor is adjusted to ensure that the vibration damping motor keeps up with the desired centrifugal force compensation angle in real time. Specifically, the PI control steps involve tracking the angle of the vibration damping motor, using the position information of the motor encoder as feedback signal, and adjusting the proportional-integral parameters to ensure that the vibration damping motor keeps up with the desired centrifugal force compensation angle in real time.

[0059] The control method of the automotive active and passive vibration isolation system device in this embodiment also includes a turning type detection step, specifically: detecting the turning type of the vehicle, including normal turns, continuous turns and S-turns;

[0060] A regular turn is a turn within 90 degrees, a continuous turn is a turn in the same direction within 3 seconds, and an S-turn is a turn in different directions within 3 seconds.

[0061] For continuous turns, the normalized values ​​calculated by the compensation angle calculation step have the same sign within a preset time, which is 3 seconds; for S-turns, the normalized values ​​calculated by the compensation angle calculation step have opposite signs within a preset time, which is 3 seconds; for normal turns, the normalized values ​​calculated by the compensation angle calculation step appear only once within a preset time, which is 3 seconds.

[0062] This embodiment also provides an automotive seat vibration isolation system, which adopts the above-mentioned automotive seat centrifugal force active compensation control algorithm, including: a control component, a damping motor 4, a scissor mechanism 6, and an air spring 7. The scissor mechanism 6 is rotatably mounted on the vehicle chassis 10, and the seat body 9 is connected to the vehicle chassis 10 through the scissor mechanism 6. The damping motor 4 drives the scissor mechanism 6 to rotate. The air spring 7 is mounted on the scissor mechanism 6 and is used to buffer the compression of the scissor mechanism 6 between the vehicle chassis 10 and the seat body 9. The control component is electrically connected to the damping motor 4 and is used to adjust the rotation of the damping motor 4.

[0063] The control components include an inertial measurement unit 1, a controller 2, and a motor driver 3. The inertial measurement unit 1 is electrically connected to the controller 2, the controller 2 is electrically connected to the motor driver 3, and the motor driver 3 is electrically connected to the vibration damping motor 4.

[0064] A mounting base is provided on the vehicle chassis 10, and the scissor fork mechanism 6 is mounted on the mounting base via a rotating bearing 8.

[0065] The scissor lift mechanism 6 includes a first connecting plate, a first scissor lift structure, a second scissor lift structure, and a second connecting plate. The first connecting plate and the second connecting plate are connected through the first scissor lift structure and the second scissor lift structure. The two ends of the first connecting plate are rotatably mounted on the mounting base through rotating bearings 8. The second connecting plate is connected to the seat body 9. The vibration damping motor 4 drives the first connecting plate to rotate, which in turn drives the entire scissor lift mechanism 6 to rotate, and in turn drives the seat body 9 to rotate. The drive end of the vibration damping motor 4 is equipped with a reducer 5, and the first connecting plate is connected to the reducer 5.

[0066] An air spring 7 is mounted on the first connecting plate. A compression plate is provided between the first scissor structure and the second scissor structure. The end of the air spring 7 away from the first connecting plate is connected to the compression plate.

[0067] The scissor mechanism 6 is also equipped with a damper, which enables a slow rebound process.

[0068] Example 2:

[0069] Those skilled in the art can understand this embodiment as a more specific description of Embodiment 1.

[0070] This embodiment provides a centrifugal force compensation control algorithm and an active and passive vibration isolation system for complex scenarios.

[0071] The centrifugal force compensation control algorithm in this embodiment mainly consists of three parts: sensor fusion algorithm, trajectory planning, and PD control.

[0072] The centrifugal force compensation control algorithm can realize centrifugal force motion compensation under various complex road conditions such as general turns, continuous turns, and S-curves. General turns refer to turns within 90 degrees, continuous turns refer to turns in the same direction within 3 seconds, and S-curves refer to turns in different directions within 3 seconds.

[0073] The active-passive hybrid vibration reduction system mainly consists of an IMU (Inertial Measurement Unit), controller, driver, motor, reducer, scissor lift mechanism, air spring, damper, and seat.

[0074] Centrifugal force compensation control algorithm:

[0075] The sensor fusion algorithm is primarily used to calculate the desired centrifugal force compensation angle when a vehicle makes a sharp turn. First, it acquires the vehicle's lateral acceleration, normal angular velocity, and speed information in inertial space. High-frequency noise in the acquired information is filtered out using an FIR digital filter. Then, the fusion algorithm normalizes the two types of information after filtering. Finally, the desired motor angle is obtained based on the mapping relationship between the normalized value, vehicle speed, and centrifugal force compensation angle. To ensure the system's anti-interference capability, the centrifugal force compensation angle of the motor is only calculated when the absolute value of the normalized value exceeds a certain threshold.

[0076] The trajectory planning algorithm is used to address the slow rebound of the seat after a vehicle has cornered. First, the maximum turning angle of the seat in the previous stage is obtained. Then, the trajectory is planned over a longer period of time, starting from the maximum turning angle and ending at zero angle. The purpose of this step is to reduce the discomfort caused by the rapid rebound of the seat.

[0077] PI control is used for motor angle tracking. It uses the position information of the motor encoder as a feedback signal and adjusts the proportional-integral parameters to ensure that the motor keeps up with the desired angle in real time.

[0078] A turn type detection module is incorporated into the centrifugal force compensation control algorithm to distinguish between normal turns, continuous turns, and S-turns. During continuous turns, the normalized values ​​calculated by the sensor fusion algorithm have the same sign for a short period; during S-turns, the normalized values ​​calculated by the sensor fusion algorithm have opposite signs for a short period; and during normal turns, the normalized value appears only once for a short period.

[0079] This invention has the function of vehicle centrifugal force compensation under various complex road conditions. The sensor fusion perception algorithm integrates the acceleration, angular velocity and speed information of the vehicle chassis, and calculates the compensation angle required under different turning radii and curvatures in real time, which has a wide range of applications.

[0080] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0081] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. An active compensation control algorithm for centrifugal force in automobile seats, characterized in that, Includes the following steps: Compensation angle calculation steps: Based on the vehicle chassis speed information, acceleration information and angular velocity information, the desired real-time centrifugal force compensation angle when the vehicle makes a sharp turn is calculated through a sensor fusion algorithm; Trajectory planning steps: Based on the maximum compensation angle of centrifugal force, plan the trajectory of the seat body during the rebound process after the vehicle has cornered; PI control steps: Based on the real-time centrifugal force compensation angle and trajectory planning results, adjust the angle of the vibration damping motor so that the vibration damping motor keeps up with the desired centrifugal force compensation angle in real time. The compensation angle calculation step specifically includes the following steps: Step a1: Obtain the vehicle's lateral acceleration, normal angular velocity, and velocity information in inertial space; Step a2: Filter the high-frequency noise in the information obtained in step a1, and normalize the filtered information to obtain a normalized value. Step a3: Obtain the expected centrifugal force compensation angle of the vibration damping motor based on the normalized value in step a2, the mapping relationship between vehicle speed and centrifugal force compensation angle; The trajectory planning steps are as follows: obtain the maximum rotation angle of the seat body during the centrifugal force compensation stage, take the maximum rotation angle as the starting point and zero angle as the ending point, and perform trajectory planning within a preset time.

2. The active compensation control algorithm for centrifugal force of automobile seats according to claim 1, characterized in that, In step a2, the high-frequency noise of the acquired information is filtered by an FIR digital filter, and the filtered information is normalized by a fusion algorithm.

3. The active compensation control algorithm for centrifugal force of automobile seats according to claim 1, characterized in that, In step a3, the mapping relationship is a mapping model based on wavelet neural network; The wavelet neural network model is set as a three-layer network, consisting of an input layer, a hidden layer, and an output layer. The neural network has three input layer nodes, representing vehicle speed. x 1. Normalized value x 2 and error feedback value x 3; The hidden layer of the neural network has 4 nodes; the output layer of the neural network has 1 node, which is the centrifugal force compensation angle; The output formula of the wavelet neural network model is: in, a j and b j These are the scaling and translation factors of the wavelet basis functions, respectively. w ij For the input layer i The node to the hidden layer j The weight of each node, w j For the hidden layer j The weights from each node to the output layer, where y is the centrifugal force compensation angle.

4. The active compensation control algorithm for centrifugal force of automobile seats according to claim 1, characterized in that, In step a3, when the absolute value of the normalized value is greater than the preset threshold, the centrifugal force compensation angle of the vibration damping motor is calculated; when the absolute value of the normalized value is less than or equal to the preset threshold, the centrifugal force compensation angle of the vibration damping motor is not calculated.

5. The active compensation control algorithm for centrifugal force of automobile seats according to claim 1, characterized in that, The PI control steps are as follows: tracking the angle of the vibration damping motor, using the position information of the motor encoder as the feedback signal, and adjusting the proportional-integral parameters to make the vibration damping motor keep up with the desired centrifugal force compensation angle in real time.

6. The active compensation control algorithm for centrifugal force of automobile seats according to claim 1, characterized in that, It also includes a turning type detection step, which specifically involves detecting the turning type of the vehicle, including normal turns, continuous turns, and S-turns. A regular turn is a turn within 90 degrees, a continuous turn is a turn in the same direction within 3 seconds, and an S-turn is a turn in different directions within 3 seconds.

7. The active compensation control algorithm for centrifugal force of automobile seats according to claim 6, characterized in that, When making continuous turns, the normalized value calculated by the compensation angle calculation step has the same sign within a preset time. When making an S-turn, the normalized value calculated by the compensation angle calculation step will have its sign reversed within a preset time. During a normal turn, the normalized value calculated by the compensation angle calculation step appears only once within a preset time.

8. A car seat vibration isolation system, characterized in that, The active compensation control algorithm for centrifugal force of automobile seats according to any one of claims 1 to 7 includes: a control component, a damping motor (4), a scissor mechanism (6), and an air spring (7). The scissor mechanism (6) is rotatably mounted on the vehicle chassis (10), and the seat body (9) is connected to the vehicle chassis (10) via the scissor mechanism (6). The vibration damping motor (4) drives the scissor mechanism (6) to rotate. The air spring (7) is disposed on the scissor mechanism (6) and the air spring (7) is used to buffer the compression of the scissor mechanism (6) between the vehicle chassis (10) and the seat body (9); The control component is electrically connected to the vibration damping motor (4), and the control component is used to adjust the rotation of the vibration damping motor (4).

Images