Six-degree-of-freedom anti-carsickness automobile seat based on passenger mass self-adaption and control method thereof

Abstract

The invention discloses a six-degree-of-freedom anti-carsickness automobile seat based on passenger mass self-adaption and a control method thereof, and relates to the technical field of intelligent automobile cabins, in particular to the six-degree-of-freedom anti-carsickness automobile seat based on passenger mass self-adaption and the control method thereof. The problems that an existing relevant seat device based on the perception conflict principle lacks control over complete six-degree-of-freedom movement and considers passenger mass difference, most schemes lacks a fault rapid locking mechanism, and the risk of out-of-control exists are solved. The method comprises the steps that firstly, force detected by a sensor on an automobile seat and the three-axis acceleration and the three-axis angular acceleration of an automobile are collected; judging whether the three-axis acceleration information of the vehicle meets a compensation motion triggering condition or not, and if yes, executing the second step; if not, continuously monitoring the three-axis acceleration information of the vehicle; 2, compensating the movement of the automobile seat; the compensation mode is full-automatic compensation; self-defined compensation is carried out; the horizontal movement freedom degree and the rotation freedom degree are locked, and only vertical vibration is compensated.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent vehicle cockpits, and particularly to a six-degree-of-freedom anti-motion-sickness vehicle seat based on occupant mass adaptation and a control method thereof. Background Art

[0002] During the process of riding in a vehicle, the irregular motion of the vehicle can cause passengers to have symptoms of motion sickness such as dizziness, nausea, and headache, commonly known as "carsickness". With the popularization of automobiles and the development of autonomous driving technology, in-vehicle activities have increased (such as reading and watching movies), and the problem of carsickness has become more prominent. The reason for the onset of motion sickness is that there is a conflict in the motion information perceived by the visual system and the balance system when the vehicle is running. If this problem cannot be alleviated, the passenger's riding experience will be greatly reduced.

[0003] In the past, the methods for alleviating motion sickness for passengers mainly included taking medications, improving the in-vehicle smell, or having passengers wear certain visual or tactile equipment. These methods are not directly efficient enough and will cause additional wearing burdens on passengers. If the seat can generate a compensatory motion in response to the vehicle's motion state, the perceived conflict can be directly alleviated. Currently, the relevant seat devices based on the principle of perceived conflict lack the control of the complete six-degree-of-freedom motion and the consideration of the differences in occupant mass, and most of the solutions lack a fast fault locking mechanism, resulting in a risk of out-of-control. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems that the existing relevant seat devices based on the principle of perceived conflict lack the control of the complete six-degree-of-freedom motion and the consideration of the differences in occupant mass, and most of the solutions lack a fast fault locking mechanism, resulting in a risk of out-of-control. A six-degree-of-freedom anti-motion-sickness vehicle seat based on occupant mass adaptation and a control method thereof are proposed.

[0005] A six-degree-of-freedom anti-motion-sickness vehicle seat based on occupant mass adaptation includes: a six-degree-of-freedom motion platform, electric cylinders, a parallel mechanism, a base, a seat body, a pressure sensor, an MPU6050 six-axis sensor, a main controller, a slave controller, and a safety redundancy module;

[0006] The six-degree-of-freedom motion platform is arranged on the base;

[0007] The seat body is arranged on the six-degree-of-freedom motion platform;

[0008] The six-degree-of-freedom motion platform includes electric cylinders and a parallel mechanism;

[0009] The pressure sensor is integrated under the seat cushion of the seat body;

[0010] The MPU6050 six-axis sensor and the main controller are integrated under the base;

[0011] The slave controller and the safety redundancy module are integrated inside the electric cylinder.

[0012] A control method for a six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation has the following specific process:

[0013] Step 1: Collect the forces detected by the sensors on the vehicle seat, as well as the vehicle's three-axis acceleration and three-axis angular acceleration information.

[0014] Judge whether the vehicle's three-axis acceleration information meets the trigger condition for compensatory motion. If it meets, execute Step 2; if not, continue to monitor the vehicle's three-axis acceleration information.

[0015] The trigger condition for compensatory motion is as follows:

[0016] The acceleration of any one axis among the vehicle's three-axis accelerations exceeds 0.1 m / s 2 or the vehicle's vertical vibration frequency is lower than 0.5 Hz;

[0017] The process for obtaining the vehicle's vertical vibration frequency is as follows:

[0018] Perform a fast Fourier transform on the vehicle's z-axis acceleration information to obtain the vehicle's vertical vibration frequency.

[0019] Step 2: The master controller receives the forces detected by the sensors on the vehicle seat, as well as the vehicle's three-axis acceleration and three-axis angular acceleration information through the CAN bus, and compensates for the movement of the vehicle seat.

[0020] The compensation methods are divided into three types, namely:

[0021] Fully automatic compensation;

[0022] Customized compensation;

[0023] Lock the horizontal translation degree of freedom and the rotation degree of freedom, and only compensate for the vertical vibration.

[0024] The beneficial effects of the present invention are as follows:

[0025] Aiming to solve the technical problems of the existing anti-motion sickness seats, such as limited degrees of freedom, insufficient compensation accuracy, and lack of occupant adaptability, resulting in limited motion sickness relief effect, a six-degree-of-freedom anti-motion sickness vehicle seat based on motion compensation and occupant mass adaptation is provided. Through a high-precision electric cylinder platform, full-degree-of-freedom dynamic compensation for X, Y, and Z-axis translation and pitch, roll, and yaw rotation is achieved. Combining distributed pressure sensors to real-time sense the occupant mass and distribution, dynamically adjust the compensation force, break through the limitations of the traditional single-direction adjustment or fixed output mode, reduce the perceptual conflict between the visual and vestibular systems from the root cause, and significantly improve the motion sickness relief effect. The present invention sets up a fast fault locking mechanism to solve the problem of out-of-control risk. Description of the Drawings

[0026] Figure 1 It is a structural schematic diagram of a six-degree-of-freedom anti-motion sickness vehicle seat device. 1 is a six-degree-of-freedom motion platform, 2 is an electric cylinder, 3 is a parallel mechanism, 4 is a base, 5 is a seat body, and 6 is a pressure sensor;

[0027] Figure 2 It is a flow chart of the present invention. Specific embodiments

[0028] Specific embodiment 1: A six-degree-of-freedom anti-motion sickness vehicle seat based on the mass adaptability of the occupant includes: a six-degree-of-freedom motion platform (1), an electric cylinder (2), a parallel mechanism (3), a base (4), a seat body (5), a pressure sensor (6), an MPU6050 six-axis sensor, a main controller, a slave controller, and a safety redundancy module;

[0029] The six-degree-of-freedom motion platform (1) is arranged on the base (4);

[0030] The seat body (5) is arranged on the six-degree-of-freedom motion platform (1);

[0031] The six-degree-of-freedom motion platform (1) includes an electric cylinder (2) and a parallel mechanism (3); it realizes the translation of the seat along the X, Y, and Z axes and the rotation around the three axes;

[0032] The pressure sensor (6) is integrated under the seat cushion of the seat body (5) for real-time detection of the occupant's mass and mass distribution;

[0033] The MPU6050 six-axis sensor and the main controller are integrated under the base (4);

[0034] The MPU6050 six-axis sensor is used to collect the vehicle's acceleration and angular velocity, and the main controller is used to process and calculate the data;

[0035] The slave controller and the safety redundancy module are integrated inside the electric cylinder (2).

[0036] The safety redundancy module includes an electromagnetic brake and an overload protection circuit. The electromagnetic brake is integrated at the tail of the motor of the electric cylinder (2) and locks the motor shaft under specific circumstances.

[0037] Specific embodiment 2: The difference between this embodiment and specific embodiment 1 is that the electric cylinder (2) is integrated inside the outer sleeve of the parallel mechanism (3) to drive the telescopic movement of the movable rod in the parallel mechanism (3) to realize the adjustment of the seat body (5).

[0038] Other steps and parameters are the same as those in specific embodiment 1.

[0039] Specific Embodiment 3: A control method for a six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation includes the following steps:

[0040] Step 1: Collect the forces detected by the sensors on the vehicle seat and the vehicle's three-axis acceleration and three-axis angular acceleration information;

[0041] Judge whether the vehicle's three-axis acceleration information meets the trigger compensation motion condition. If it meets, execute Step 2; if not, continue to monitor the vehicle's three-axis acceleration information;

[0042] The trigger compensation motion condition is:

[0043] The acceleration of any one axis in the vehicle's three-axis acceleration exceeds 0.1 m / s 2 or the vehicle's vertical vibration frequency is lower than 0.5 Hz;

[0044] The process of obtaining the vehicle's vertical vibration frequency is:

[0045] Perform a fast Fourier transform on the vehicle's z-axis acceleration information to obtain the vehicle's vertical vibration frequency;

[0046] Step 2: The main controller receives the forces detected by the sensors on the vehicle seat and the vehicle's three-axis acceleration and three-axis angular acceleration information through the CAN bus, and compensates for the movement of the vehicle seat;

[0047] The compensation methods are divided into three types, namely:

[0048] Fully automatic compensation;

[0049] Customized compensation;

[0050] Lock the horizontal translation degree of freedom and the rotation degree of freedom, and only compensate for the vertical vibration.

[0051] A six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation includes: a six-degree-of-freedom motion platform, an electric cylinder, a parallel mechanism, a base, a seat body, a pressure sensor, an MPU6050 six-axis sensor, a main controller, a slave controller, and a safety redundancy module;

[0052] The six-degree-of-freedom motion platform is arranged on the base;

[0053] The seat body is arranged on the six-degree-of-freedom motion platform;

[0054] The six-degree-of-freedom motion platform includes an electric cylinder and a parallel mechanism; it realizes the translation of the seat along the X, Y, and Z axes and the rotation around the three axes;

[0055] The pressure sensor is integrated under the seat cushion of the seat body and is used to detect the occupant mass and mass distribution in real time;

[0056] The MPU6050 six-axis sensor and the main controller are integrated under the base;

[0057] The MPU6050 six-axis sensor is used to collect the vehicle acceleration and angular velocity, and the main controller is used to process and calculate the data;

[0058] The slave controller and the safety redundancy module are integrated inside the electric cylinder.

[0059] The safety redundancy module includes an electromagnetic brake and an overload protection circuit. The electromagnetic brake is integrated at the tail of the motor of the electric cylinder and locks the motor shaft under specific circumstances.

[0060] The electric cylinder is integrated inside the outer sleeve of the parallel mechanism, and drives the telescopic movement of the movable rod in the parallel mechanism to realize the adjustment of the seat body.

[0061] Specific Embodiment 4: The difference between this embodiment and Specific Embodiment 3 is that in step 1, the forces detected by the sensors on the vehicle seat and the information of the vehicle's three-axis acceleration and three-axis angular acceleration are collected; the specific process is as follows:

[0062] The MPU6050 six-axis sensor obtains the vehicle's three-axis acceleration and three-axis angular acceleration;

[0063] The pressure sensor (6) obtains the forces detected on the vehicle seat;

[0064] The three-axis coordinate system is: the x-axis is the vehicle forward direction, the z-axis is perpendicular to the vehicle chassis and upward, the y-axis is perpendicular to the xz plane, and xyz follows the right-hand rule.

[0065] Other steps and parameters are the same as those in Specific Embodiment 3.

[0066] Specific Embodiment 5: The difference between this embodiment and Specific Embodiment 3 or 4 is that the specific process of the full-automatic compensation in step 2 is as follows:

[0067] 11), According to the vehicle's three-axis acceleration and three-axis angular acceleration information obtained by the MPU6050 six-axis sensor, calculate the seat target compensation acceleration [Δa x , Δa y , Δa z , Δβ x , Δβ y , Δβ z , and the expression is:

[0068] Δa x =-k×a x , Δa y =-k×a y , Δa z =-k×a z

[0069] Δβ x = -k×β x , Δβ y = -k×β y , Δβ z = -k×β z

[0070] wherein,

[0071] Δa x is the target compensation acceleration of the x-axis, Δa y is the target compensation acceleration of the y-axis, Δa z is the target compensation acceleration of the z-axis;

[0072] Δβ x is the target compensation angular acceleration about the x-axis, Δβ y is the target compensation angular acceleration about the y-axis, Δβ z is the target compensation angular acceleration about the z-axis; the target is a six-degree-of-freedom motion platform (1);

[0073] k is the space limitation coefficient;

[0074] a x , a y , a z are the accelerations of the vehicle's x, y, and z axes respectively;

[0075] β x , β y , β z are the angular accelerations of the vehicle's x, y, and z axes respectively;

[0076] 12), Calculate the occupant mass m according to the force detected on the vehicle seat obtained by the pressure sensor (6); the calculation formula is:

[0077]

[0078] wherein, is the force detected by the th pressure sensor, g = 9.8 m / s 2 , n is the total number of pressure sensors;

[0079] 13), Calculate the occupant centroid coordinates (x c , y c ); the calculation formula is:

[0080]

[0081] wherein, is the coordinate of the th pressure sensor on the x, y axes;

[0082] 14), when the coordinates of the occupant's center of mass (x c , y c ) deviate from the geometric center of the seat (known), the vehicle acceleration (such as turning, sudden braking) generates an additional inertial moment, resulting in the imbalance of the seat attitude. The moment calculation formula is:

[0083] τ x =-m×[a y ×z c -a z ×y c

[0084] τ y =-m×[a z ×x c -a x ×z c

[0085] τ z =-m×[a x ×y c -a y ×x c

[0086] Among them,

[0087] τ x represents the moment about the x-axis; τ y represents the moment about the y-axis; τ z represents the moment about the z-axis; z c represents the z-axis coordinate of the occupant's center of mass (preset value), which is a constant;

[0088] 15), based on the additional inertial moment generated by the vehicle acceleration (such as turning, sudden braking) when the center of mass deviates, obtain the final target compensation angular acceleration [Δβ x +δβ x , Δβ y +δβ y , Δβ z +δβ y ; the specific process is:

[0089] Based on the additional inertial moments τ x , τ y , τ z generated by the vehicle acceleration (such as turning, sudden braking) when the center of mass deviates, obtain the moment compensation acceleration [δβ x , δβ y , δβ y caused by the deviation of the center of mass, which is expressed as:

[0090] ​​​

[0091] where k z is the vertical stiffness coefficient, I xx is the moment of inertia of the six-degree-of-freedom motion platform about the x-axis, and I yy is the moment of inertia of the six-degree-of-freedom motion platform about the y-axis;

[0092] Based on the target compensation angular acceleration of the seat [Δβ x , Δβ y , Δβ z , the torque compensation acceleration [δβ x , δβ y , δβ y caused by the centroid offset is superimposed to obtain the final target compensation angular acceleration [Δβ x + δβ x , Δβ y + δβ y , Δβ z + δβ y ;

[0093] where Δβ x + δβ x is the final target compensation angular acceleration about the x-axis, Δβ y + δβ y is the final target compensation angular acceleration about the y-axis, and Δβ z + δβ y is the final target compensation angular acceleration about the z-axis; 16)

[0095] Based on the final target compensation acceleration of the seat [Δa x , Δa y , Δa z , Δβ x + δβ x , Δβ y + δβ y , Δβ z + δβ y , calculate the target length L i,目标 formed by the sleeve and the movable rod extending from the sleeve in the parallel mechanism (3), i = 1, 2,..., 6;

[0096] 17) Real-time detect the actual length L i,实际 formed by the sleeve and the movable rod extending from the sleeve of the i-th; The specific process is as follows:

[0097] The actual length L i,实际 formed by the sleeve and the movable rod extending from the sleeve of the i-th is detected in real time through the linear encoder built in the electric cylinder (2), and the measurement formula is:

[0098]

[0099] where N is the number of encoder pulses, P is the lead of the ball screw built in the electric cylinder (2), and R is the encoder resolution; L 套筒 is the sleeve length;

[0100] 18), based on the i-th target length L i,目标 and the i-th actual length L i,实际 calculate the i-th closed-loop error; the specific process is as follows:

[0101] e i (k) = L i,目标 - L i,实际

[0102] where e i (k) is the error signal at time k;

[0103] The error signal e i (k) is used as the closed-loop control input;

[0104] 19), based on the i-th error signal e i (k) calculate the i-th control quantity u i (k) ； The specific process is as follows:

[0105]

[0106] where,

[0107] Δt′ is the control response time, K p , K i , K d are the PID control coefficients, which are dynamically adjusted according to the system state;

[0108] e i (j) is the error signal at time j, e i (k - 1) is the error signal at time k - 1;

[0109] 110), convert the i-th control quantity u i (k) into the motor speed command ω m,i , and the motor speed command ω m,i controls the rotation of the motor in the electric cylinder (2). The motor drives the ball screw to rotate, and the ball screw drives the movable rod to expand and contract; the specific process is as follows:

[0110] Convert the i-th control quantity u i (k) into the motor speed command ω m,i , the specific process is as follows:

[0111]

[0112] Among them, K v is the motor speed constant, and K t is the motor torque constant;

[0113] The motor speed command ω m,i controls the rotation of the motor in the electric cylinder (2). The motor drives the ball screw to rotate, and the ball screw drives the movable rod to expand and contract.

[0114] Other steps and parameters are the same as those in the third or fourth specific implementation manners.

[0115] Specific implementation manner six: The difference between this implementation manner and one of the third to fifth specific implementation manners is that: in the above (16), based on the final target compensation accelerations of the seat [Δa x , Δa y , Δa z , Δβ x +δβ x , Δβ y +δβ y , Δβ z +δβ y , the target length L i,目标 formed by the sleeve and the movable rod extending out of the sleeve in the parallel mechanism (3) is calculated, where i = 1, 2,..., 6; the specific process is as follows:

[0116] 161) During the sensor response time Δt, the acceleration and angular acceleration are converted into displacement and angle increments through double integration:

[0117] Δx = ∫∫Δa x dt 2 , Δy = ∫∫Δa y dt 2 , Δz = ∫∫Δa z dt 2

[0118] θ x = ∫∫(Δβ x +δβ x )dt 2 , θ y = ∫∫(Δβ y +δβ y )dt 2 , θ z = ∫∫(Δβ z +δβ z )dt 2

[0119] Among them,

[0120] Δx represents the displacement of the x-axis, Δy represents the displacement of the y-axis, and Δz represents the displacement of the z-axis;

[0121] θx Represents the x-axis angle increment, θ y Represents the y-axis angle increment, θ z Represents the z-axis angle increment;

[0122] 162), Calculate the coordinates of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5) based on the x-axis displacement Δx, y-axis displacement Δy, z-axis displacement Δz, and the rotation matrix obtained from the angle increments

[0123] Wherein,

[0124] x B0i Represents the initial x-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5), y B0i Represents the initial y-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5), z B0i Represents the initial z-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5); x B0i 、y B0i 、z B0i Are known; i = 1, 2,..., 6

[0125] x Bi Represents the target x-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5), y Bi Represents the target y-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5), z Bi Represents the target z-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5); i = 1, 2,..., 6;

[0126] R is the rotation matrix;

[0127]

[0128] Wherein, R z (θ z ) Represents the rotation matrix about the z-axis, R y (θ y ) Represents the rotation matrix about the y-axis, R x (θ x ) Represents the rotation matrix about the x-axis;

[0129] 163), Calculate the target length L formed by the i-th sleeve and the movable rod extending from the sleeve based on the hinge point coordinates at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5) i,目标 , i = 1, 2,..., 6:

[0130]

[0131] Among them,

[0132] (x Ai , y Ai , z Ai ) is the coordinate of the i-th hinge point (6 hinges) at the connection between the base (4) and the six-degree-of-freedom motion platform (1), i = 1, 2,..., 6; known quantity, fixed value.

[0133] Other steps and parameters are the same as those in any one of the third to fifth specific embodiments.

[0134] Specific embodiment seven: The difference between this embodiment and any one of the third to sixth specific embodiments is that: the electric cylinder (2) includes a controller and a safety redundancy module;

[0135] The safety redundancy module forcibly locks the six-degree-of-freedom platform (1) when any of the following conditions is triggered:

[0136] It is detected that the vehicle has suffered an abnormal collision; the occupant mass > 150 kg;

[0137] The motor current ≥ rated current or the temperature ≥ 80 °C;

[0138] The CAN bus communication is interrupted for more than 200 ms.

[0139] The safety redundancy module includes an electromagnetic brake and an overload protection circuit. The electromagnetic brake is integrated at the tail of the motor of the electric cylinder (2) and locks the motor shaft under specific circumstances.

[0140] Other steps and parameters are the same as those in any one of the third to sixth specific embodiments.

[0141] Specific embodiment eight: The difference between this embodiment and the third or fourth specific embodiment is that: the custom compensation in step two; the specific process is as follows:

[0142] 21), According to the vehicle three-axis acceleration and three-axis angular acceleration information obtained by the MPU6050 six-axis sensor (7), calculate the seat target compensation acceleration [Δa x , Δa y , Δa z , Δβ x , Δβ y , Δβ z , and the expression is:

[0143] Δa x = -k × a x , Δa y = -k × a y , Δa z = -k × a z

[0144] Δβ x =-k×β x , Δβ y =-k×β y , Δβ z =-k×β z

[0145] wherein,

[0146] Δa x is the target compensation acceleration of the x-axis, Δa y is the target compensation acceleration of the y-axis, Δa z is the target compensation acceleration of the z-axis;

[0147] Δβ x is the target compensation angular acceleration about the x-axis, Δβ y is the target compensation angular acceleration about the y-axis, Δβ z is the target compensation angular acceleration about the z-axis; the target is the six-degree-of-freedom motion platform (1);

[0148] k is the space limitation coefficient;

[0149] a x , a y , a z are the accelerations of the vehicle's x, y, and z axes respectively;

[0150] β x , β y , β z are the angular accelerations of the vehicle's x, y, and z axes respectively;

[0151] 22), Calculate the occupant mass m according to the force detected on the vehicle seat obtained by the pressure sensor (6); the calculation formula is:

[0152]

[0153] wherein, is the force detected by the th pressure sensor, g = 9.8 m / s 2 , n is the total number of pressure sensors;

[0154] 23), Calculate the occupant centroid coordinates (x c , y c ); the calculation formula is:

[0155]

[0156] where is the The coordinates of a pressure sensor on the x and y axes;

[0157] 24) When the coordinates of the occupant's center of mass (x c , y c ) deviate from the geometric center of the seat (known), the vehicle acceleration (such as turning or sudden braking) generates an additional inertial moment, causing the seat attitude to become unbalanced. The moment calculation formula is:

[0158] τ x =-m×[a y ×z c -a z ×y c

[0159] τ y =-m×[a z ×x c -a x ×z c

[0160] τ z =-m×[a x ×y c -a y ×x c

[0161] Where,

[0162] τ x represents the moment about the x-axis; τ y represents the moment about the y-axis; τ z represents the moment about the z-axis; z c represents the z-axis coordinate of the occupant's center of mass (preset value)

[0163] 25) Based on the additional inertial moment generated by the vehicle acceleration (such as turning or sudden braking) when the center of mass is offset, obtain the final target compensation angular acceleration [Δβ x +δβ x , Δβ y +δβ y , Δβ z +δβ y ; The specific process is as follows:

[0164] Based on the additional inertial moments τ x , τ y , τ z generated by the vehicle acceleration (such as turning or sudden braking) when the center of mass is offset, obtain the moment compensation acceleration [δβ x , δβ y , δβ y caused by the center of mass offset, which is expressed as:

[0165] ​​​

[0166] Among them, k z is the vertical stiffness coefficient,

[0167] I xx is the moment of inertia of the six-degree-of-freedom motion platform about the x-axis, and I yy is the moment of inertia of the six-degree-of-freedom motion platform about the y-axis;

[0168] On the basis of the target compensation angular acceleration of the seat [Δβ x , Δβ y , Δβ z , the torque compensation acceleration [δβ x , δβ y , δβ y caused by the centroid offset is superimposed to obtain the final target compensation angular acceleration [Δβ x + δβ x , Δβ y Δδβ y , Δβ z + δβ y ;

[0169] Among them, Δβ x + δβ x is the final target compensation angular acceleration about the x-axis, Δβ y + δβ y is the final target compensation angular acceleration about the y-axis, and Δβ z + δβ y is the final target compensation angular acceleration about the z-axis; 26)、

[0171] Multiply the final target compensation acceleration of the seat [Δa x , Δa y , Δa z , Δβ x + δβ x , Δβ y + δβ y , Δβ z + δβ y by the compensation intensity coefficient ε, 0 ≤ ε < 100%, to obtain the customized target compensation acceleration of the seat [εΔa x , εΔa y , εΔa z , ε(Δβ x + δβ x ), ε(Δβ y + δβ y ), ε(Δβ z + δβ y , and calculate the target length jointly formed by the sleeve and the movable rod extending out of the sleeve in the parallel mechanism (3);

[0172] 27), Real-time detect the actual length L formed by the i-th sleeve and the movable rod extending out of the sleeve i,实际 ; The specific process is as follows:

[0173] Real-time detect the actual length L formed by the i-th sleeve and the movable rod extending out of the sleeve through the linear encoder built in the electric cylinder (2) i,实际 , and the measurement formula is:

[0174]

[0175] where N is the encoder pulse number, P is the lead of the ball screw built in the electric cylinder (2), and R is the encoder resolution; L 套筒 is the length;

[0176] 28), Based on the i-th target length L i,目标 and the i-th actual length L i,实际 calculate the i-th closed-loop error; The specific process is as follows:

[0177] e i (k) = L i,目标 - L i,实际

[0178] where e i (k) is the error signal at time k;

[0179] The error signal e i (k) is used as the closed-loop control input;

[0180] 29), Based on the i-th error signal e i (k) calculate the i-th control quantity u i (k) ； The specific process is as follows:

[0181]

[0182] where,

[0183] Δt′ is the control response time, K p , K i , K d are the PID control coefficients, which are dynamically adjusted according to the system state;

[0184] e i (j) is the error signal at time j, e i (k - 1) is the error signal at time k - 1;

[0185] 210), Convert the i-th control quantity u i (k) into the motor speed command ω m,i , and the motor speed command ω m,iControl the rotation of the motor in the electric cylinder (2). The motor drives the ball screw to rotate, and the ball screw drives the movable rod to extend and retract. The specific process is as follows:

[0186] Convert the i-th control quantity u i (k) into the motor speed command ω m,i , and the specific process is as follows:

[0187]

[0188] where K v is the motor speed constant, and K t is the motor torque constant;

[0189] The motor speed command ω m,i controls the rotation of the motor in the electric cylinder (2). The motor drives the ball screw to rotate, and the ball screw drives the movable rod to extend and retract;

[0190] The electric cylinder (2) includes a slave controller and a safety redundancy module;

[0191] The safety redundancy module forcibly locks the six-degree-of-freedom platform (1) when any of the following conditions is triggered:

[0192] It is detected that the vehicle has suffered an abnormal collision; the occupant mass > 150 kg;

[0193] The motor current ≥ rated current or the temperature ≥ 80 °C;

[0194] The CAN bus communication is interrupted for more than 200 ms.

[0195] The safety redundancy module includes an electromagnetic brake and an overload protection circuit. The electromagnetic brake is integrated at the tail of the motor of the electric cylinder (2) and locks the motor shaft under specific circumstances.

[0196] Other steps and parameters are the same as those in the third or fourth specific implementation manners.

[0197] Specific implementation manner nine: The difference between this implementation manner and the eighth specific implementation manner is that in the 26), the final target compensation acceleration of the seat [Δa x , Δa y , Δa z , Δβ x +δβ x , Δβ y +δβ y , Δβ z +δβ y is multiplied by the compensation intensity coefficient ε, 0 ≤ ε < 100%, to obtain the custom seat target compensation acceleration [εΔa x , εΔa y , εΔa z , ε(Δβ x+δβ x ), ε(Δβ y +δβ y ), ε(Δβ z +δβ y ), calculate the target length jointly formed by the sleeve and the movable rod extending from the sleeve in the parallel mechanism (3);

[0198] The specific process is as follows: 261),

[0200] Multiply the final target compensation acceleration of the seat [Δa x , Δa y , Δa z , Δβ x +δβ x , Δβ y +δβ y , Δβ z +δβ y by the compensation intensity coefficient ε, 0 ≤ ε < 100%, to obtain the customized seat target compensation acceleration [εΔa x , εΔa y , εΔa z , ε(Δβ x +δβ x ), ε(Δβ y +δβ y ), ε(Δβ z +δβ y );

[0201] Among them,

[0202] εΔa x is the customized target compensation acceleration for the x-axis, εΔa y is the customized target compensation acceleration for the y-axis, εΔa z is the customized target compensation acceleration for the z-axis, ε(Δβ x +δβ x ) is the customized target compensation angular acceleration about the x-axis, ε(Δβ y +δβ y ) is the customized target compensation angular acceleration about the y-axis, ε(Δβ z +δβ y ) is the customized target compensation angular acceleration about the z-axis;

[0203] Within the sensor response time Δt, convert the acceleration and angular acceleration into displacement and angle increments through double integration:

[0204] Δx = ∫∫εΔa x dt 2 , Δy = ∫∫εΔa y dt 2, Δz = ∫∫εΔa z dt 2

[0205] θ x = ∫∫ε(Δβ x + δβ x )dt 2 , θ y = ∫∫ε(Δβ y + δβ y )dt 2 , θ z = ∫∫ε(Δβ z + δβ z )dt 2

[0206] wherein,

[0207] Δx represents the x-axis displacement, Δy represents the y-axis displacement, and Δz represents the z-axis displacement;

[0208] θ x represents the x-axis angle increment, θ y represents the y-axis angle increment, θ z represents the z-axis angle increment; 262),

[0210] Calculate the coordinates of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5) based on the x-axis displacement Δx, y-axis displacement Δy, z-axis displacement Δz, and the rotation matrix obtained from the angle increments

[0211] wherein,

[0212] x B0i represents the initial x-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5), y B0i represents the initial y-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5), z B0i represents the initial z-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5); x B0i , y B0i , z B0i are known; i = 1, 2,..., 6

[0213] x Bi represents the target x-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5), y Bi represents the target y-axis coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5), z BiIt represents the z-axis target coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5); i = 1, 2,..., 6;

[0214] R is the rotation matrix;

[0215]

[0216] Among them, R z (θ z ) represents the rotation matrix corresponding to the z-axis angle increment θ z , and R y (θ y ) represents the rotation matrix corresponding to the y-axis angle increment θ y , and R x (θ x ) represents the rotation matrix corresponding to the x-axis angle increment θ x ;

[0217] 263), Based on the hinge point coordinates at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5), calculate the target length L composed of the i-th sleeve and the movable rod extending out of the sleeve, i = 1, 2,..., 6: i,目标 , i = 1, 2,..., 6:

[0218]

[0219] Among them,

[0220] (x Ai , y Ai , z Ai ) are the coordinates of the i-th hinge point (6 hinges) at the connection between the base (4) and the degree-of-freedom motion platform (1); known quantities, fixed values.

[0221] Other steps and parameters are the same as those in the eighth specific implementation manner.

[0222] Tenth specific implementation manner: The difference between this implementation manner and the third or fourth specific implementation manner is that in step 2, the horizontal movement degree of freedom and the rotational degree of freedom are locked, and only vertical vibration compensation is performed; the specific process is:

[0223] 31), According to the z-axis acceleration information obtained by the MPU6050 six-axis sensor, calculate the target compensation acceleration Δa of the seat in the z-axis z , and the expression is:

[0224] Δa z =-k×a z

[0225] Among them, Δa z is the target compensation acceleration in the z-axis; the target is the six-degree-of-freedom motion platform (1);

[0226] k is the space limit coefficient; a z is the vehicle z-axis acceleration;

[0227] 32), within the sensor response time Δt, convert the z-axis acceleration to displacement Δz = ∫∫Δa z dt 2 ;

[0228] where Δz represents the z-axis displacement;

[0229] Calculate the z-axis coordinate z of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5) Bi = z B0i + Δz (x and y axis coordinates remain in place)

[0230] where,

[0231] z Bi represents the z-axis target coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5);

[0232] z B0i represents the z-axis initial coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5); z B0i is known;

[0233] Based on the z-axis coordinate z of the i-th hinge point at the connection between the six-degree-of-freedom motion platform (1) and the seat body (5) Bi , calculate the target length L composed of the i-th sleeve and the movable rod of the extended sleeve i,目标 , i = 1, 2,..., 6, expressed as:

[0234]

[0235] z Ai is the z-axis coordinate of the i-th hinge point at the connection between the base (4) and the six-degree-of-freedom motion platform (1) (6 hinges), i = 1, 2,..., 6; known quantity, fixed value;

[0236] 33), Real-time detect the actual length L composed of the i-th sleeve and the movable rod of the extended sleeve i,实际 ; The specific process is:

[0237] Real-time detect the actual length L composed of the i-th sleeve and the movable rod of the extended sleeve through the linear encoder built in the electric cylinder (2) i,实际 , and the measurement formula is:

[0238]

[0239] Where N is the number of encoder pulses;

[0240] P is the lead of the ball screw built in the electric cylinder;

[0241] R is the encoder resolution;

[0242] L 套筒 is the sleeve length;

[0243] 34), Calculate the i-th closed-loop error based on the i-th target length L i,目标 and the i-th actual length L i,实际 Calculate the i-th closed-loop error;

[0244] The specific process is as follows:

[0245] e i (k) = L i,目标 -L i,实际

[0246] Where e i (k) is the error signal at time k;

[0247] The error signal e i (k) is used as the closed-loop control input;

[0248] 35), Calculate the i-th control quantity u i (k) based on the i-th error signal e i (k) ； The specific process is as follows:

[0249]

[0250] Where,

[0251] ×t′ is the control response time;

[0252] K p , K i , K d are the PID control coefficients, which are dynamically adjusted according to the system state;

[0253] e i (j) is the error signal at time j, e i (k - 1) is the error signal at time k - 1;

[0254] 36), Convert the i-th control quantity u i (k) to the motor speed command ω m,i , The motor speed command ω m,i controls the rotation of the motor in the electric cylinder (2). The motor drives the ball screw to rotate, and the ball screw drives the movable rod to expand and contract; The specific process is as follows:

[0255] Convert the i-th control quantity u i(k) is converted into the motor speed command ω m,i , and the specific process is as follows:

[0256]

[0257] Among them, K v is the motor speed constant, and K t is the motor torque constant;

[0258] The motor speed command ω m,i controls the rotation of the motor in the electric cylinder (2). The motor drives the ball screw to rotate, and the ball screw drives the movable rod to extend and retract.

[0259] Other steps and parameters are the same as those in the third or fourth specific implementation manners.

[0260] The present invention can also have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding changes and deformations should all fall within the protection scope of the appended claims of the present invention.

Claims

1. A six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation, characterized in that: The six-degree-of-freedom anti-motion-sickness vehicle seat based on occupant mass adaptation includes: a six-degree-of-freedom motion platform, an electric cylinder, a parallel mechanism, a base, a seat body, a pressure sensor, an MPU6050 six-axis sensor, a main controller, a slave controller, and a safety redundancy module; The six-degree-of-freedom motion platform is arranged on the base; The seat body is arranged on the six-degree-of-freedom motion platform; The six-degree-of-freedom motion platform includes an electric cylinder and a parallel mechanism; The pressure sensor is integrated under the seat cushion of the seat body; The MPU6050 six-axis sensor and the main controller are integrated under the base; The slave controller and the safety redundancy module are integrated inside the electric cylinder.

2. The six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation according to claim 1, characterized in that: The electric cylinder is integrated inside the outer sleeve of the parallel mechanism and drives the telescopic movement of the movable rod in the parallel mechanism.

3. A control method for a six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation, characterized in that: The specific process of the method is as follows: Step 1: Collect the forces detected by the sensors on the vehicle seat and the information of the vehicle's three-axis acceleration and three-axis angular acceleration; Judge whether the vehicle's three-axis acceleration information meets the trigger condition for compensating motion. If it meets, execute Step 2; if not, continue to monitor the vehicle's three-axis acceleration information; The trigger condition for compensating motion is: The acceleration of any one of the three axes of the vehicle exceeds 0.1 m / s 2 or the vertical vibration frequency of the vehicle is lower than 0.5 Hz; The acquisition process of the vehicle's vertical vibration frequency is: Perform a fast Fourier transform on the vehicle's z-axis acceleration information to obtain the vehicle's vertical vibration frequency; Step 2: The main controller receives the forces detected by the sensors on the vehicle seat and the information of the vehicle's three-axis acceleration and three-axis angular acceleration through the CAN bus, and compensates for the movement of the vehicle seat; The compensation methods are divided into three types, namely: Fully automatic compensation; Customized compensation; Lock the horizontal movement degree of freedom and the rotation degree of freedom, and only compensate for the vertical vibration.

4. The control method of a six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation according to claim 3, wherein: In Step 1, collect the forces detected by the sensors on the vehicle seat and the information of the vehicle's three-axis acceleration and three-axis angular acceleration; The specific process is: The MPU6050 six-axis sensor obtains the vehicle's three-axis acceleration and three-axis angular acceleration; The pressure sensor obtains the forces detected on the vehicle seat; The three-axis coordinate system is: the x-axis is the vehicle forward direction, the z-axis is perpendicular to the vehicle chassis upward, the y-axis is perpendicular to the xz plane, and xyz follows the right-hand rule.

5. The control method of a six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation according to claim 4, characterized in that: The specific process of the fully automatic compensation in Step 2 is: 11) Calculate the target compensation acceleration of the seat [Δa x , Δa y , Δa z , Δβ x , Δβ y , Δβ z according to the vehicle's three-axis acceleration and three-axis angular acceleration information obtained by the MPU6050 six-axis sensor. The expression is: Δa x =-k×a x ,Δa y =-k×a y ,Δa z =-k×a z Δβ x =-k×β x ,Δβ y =-k×β y ,Δβ z =-k×β z Among them, Δa x is the target compensation acceleration for the x-axis, Δa y is the target compensation acceleration for the y-axis, Δa z is the target compensation acceleration for the z-axis; Δβ x is the target compensation angular acceleration about the x-axis, Δβ y is the target compensation angular acceleration about the y-axis, Δβ z is the target compensation angular acceleration about the z-axis; k is the space limit coefficient; a x , a y , a z are the accelerations of the x, y, and z axes of the vehicle respectively; β x , β y , β z are the angular accelerations of the x, y, and z axes of the vehicle, respectively; 12), Calculate the occupant mass m according to the forces detected on the vehicle seat obtained by the pressure sensor; the calculation formula is: Among them, is the force detected by the th pressure sensor, g = 9.8 m / s 2 , and n is the total number of pressure sensors; 13), calculating the occupant centroid coordinates (x c , y c ) according to the force detected on the vehicle seat obtained by the pressure sensor; the calculation formula is: Among them, is the coordinate of the th pressure sensor on the x and y axes; 14) When the occupant's centroid coordinates (x c , y c ) deviate from the geometric center of the seat, the vehicle acceleration generates an additional inertial moment, and the moment calculation formula is: τ x = -m×[a y ×z c -a z ×y c ​ τ y = -m×[a z ×x c -a x ×z c ​ τ z = -m × [a x × y c - a y × x c ​ Among them, τ x represents the moment about the x-axis; τ y represents the moment about the y-axis; τ z represents the moment about the z-axis; z c represents the z-axis coordinate of the occupant's center of mass, which is a constant; 15), based on the additional inertial torque generated by the vehicle acceleration during centroid offset, obtain the final target compensation angular acceleration [Δβ x +δβ x ,Δβ y +δβ y ,Δβ z +δβ y ; The specific process is as follows: The additional inertial torque τ generated by the vehicle acceleration when the centroid shifts x , τ y , τ z , the torque compensation acceleration [δβ x , δβ y , δβ y caused by the centroid shift is obtained, which is expressed as: where k z is the vertical stiffness coefficient, I xx is the moment of inertia of the six-degree-of-freedom motion platform about the x-axis, and I yy is the moment of inertia of the six-degree-of-freedom motion platform about the y-axis; Based on the target compensation angular accelerations of the seat [Δβ x , Δβ y , Δβ z , the moment compensation accelerations caused by the centroid offset [δβ x , δβ y , δβ y are superimposed to obtain the final target compensation angular accelerations [Δβ x + δβ x , Δβ y + δβ y , Δβ z + δβ y ; where, Δβ x +δβ x is the final target compensation angular acceleration about the x-axis, Δβ y +δβ y is the final target compensation angular acceleration about the y-axis, Δβ z +δβ y is the final target compensation angular acceleration about the z-axis; 16)、 Based on the final target compensation acceleration of the seat [Δa x , Δa y , Δa z , Δβ x + δβ x , Δβ y + δβ y , Δβ z + δβ y , calculate the target length L jointly composed of the sleeve and the movable rod extending the sleeve in the parallel mechanism i,目标 , i = 1, 2,..., 6; 17) Real-time detection of the actual length L formed by the i-th sleeve and the movable rod extending from the sleeve i,实际 ; The specific process is as follows: The actual length L formed by the i-th sleeve and the movable rod extending from the sleeve is detected in real time by a linear encoder built into the electric cylinder i,实际 , and the measurement formula is: where N is the number of encoder pulses, P is the lead of the ball screw built into the electric cylinder, R is the encoder resolution; L 套筒 is the sleeve length; 18) Based on the i-th target length L i,目标 and the i-th actual length L i,实际 calculate the i-th closed-loop error; the specific process is as follows: e i (k) = L i,目标 -L i,实际 where e i (k) is the error signal at time k; 19) Calculate the i-th control quantity u i (k) based on the i-th error signal e i (k) ； The specific process is as follows: Among them, Δt′ is the control response time, K p , K i , K d are the PID control coefficients; e i (j) is the error signal at time j, e i (k - 1) is the error signal at time k - 1; 110), convert the i-th control quantity u i (k) into the motor speed command ω m,i , and the motor speed command ω m,i controls the rotation of the motor in the electric cylinder. The motor drives the ball screw to rotate, and the ball screw drives the movable rod to extend and retract. The specific process is as follows: Convert the $i$-th control quantity $u$ i (k) into the motor speed command $\omega$ m,i , and the specific process is as follows: Among them, K v is the motor speed constant, and K t is the motor torque constant; Motor speed command ω m,i Control the rotation of the motor in the electric cylinder. The motor drives the ball screw to rotate, and the ball screw drives the movable rod to extend and retract.

6. A control method for a six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation according to claim 5, characterized in that: The target compensation acceleration [Δa x , Δa y , Δa z , Δβ x +δβ x , Δβ y +δβ y , Δβ z +δβ y in (16) is used to calculate the target length L formed by the sleeve and the movable rod extending from the sleeve in the parallel mechanism i,目标 , where i = 1, 2,..., 6; the specific process is as follows: 161), Within the sensor response time Δt, convert the acceleration and angular acceleration into displacement and angle increments through double integration: Δx = ∫∫Δa x dt 2 , Δy = ∫∫Δa y dt 2 , Δz = ∫∫Δa z dt 2 θ x = ∫∫(Δβ x + δβ x )dt 2 , θ y = ∫∫(Δ\β y + δβ y )dt 2 , θ z = ∫∫(Δβ z + δβ z )dt 2 Among them, Δx represents the x-axis displacement, Δy represents the y-axis displacement, and Δz represents the z-axis displacement; θ x represents the x-axis angle increment, θ y represents the y-axis angle increment, θ z represents the z-axis angle increment; 162) Calculate the coordinates of the hinge point at the connection between the six-degree-of-freedom motion platform and the seat body for the i-th one based on the displacement Δx along the x-axis, displacement Δy along the y-axis, displacement Δz along the z-axis, and the rotation matrix obtained with an angular increment Among them, x B0i represents the initial x - axis coordinate of the i - th hinge point at the connection between the six - degree - of - freedom motion platform and the seat body, y B0i represents the initial y - axis coordinate of the i - th hinge point at the connection between the six - degree - of - freedom motion platform and the seat body, z B0i represents the initial z - axis coordinate of the i - th hinge point at the connection between the six - degree - of - freedom motion platform and the seat body; i = 1, 2,..., 6 x Bi represents the x-axis target coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform and the seat body, y Bi represents the y-axis target coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform and the seat body, z Bi represents the z-axis target coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform and the seat body; i = 1, 2,..., 6; R is the rotation matrix; wherein, R z (θ z ) represents the rotation matrix about the z-axis, R y (θ y ) represents the rotation matrix about the y-axis, R x (θ x ) represents the rotation matrix about the x-axis; 163), calculate the target length L formed by the i-th sleeve and the movable rod extending from the sleeve based on the hinge point coordinates at the connection between the six-degree-of-freedom motion platform and the seat body, where i = 1, 2,..., 6: i,目标 , i = 1, 2,..., 6: Among them, (x Ai , y Ai , z Ai ) is the coordinate of the i-th hinge point at the connection between the base and the six-degree-of-freedom motion platform, where i = 1, 2,..., 6.

7. A control method for a six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation according to claim 4, characterized in that: The electric cylinder includes a slave controller and a safety redundancy module; The safety redundancy module forcibly locks the six-degree-of-freedom platform when any of the following conditions is triggered: It is detected that the vehicle has suffered an abnormal collision; the occupant mass > 150 kg; The motor current ≥ rated current or the temperature ≥ 80 °C; The CAN bus communication is interrupted for more than 200 ms.

8. A control method for a six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation according to claim 4, characterized in that: The customized compensation in Step 2; the specific process is: 21) Calculate the target compensation acceleration of the seat [Δa x , Δa y , Δa z , Δβ x , Δβ y , Δβ z according to the vehicle three-axis acceleration and three-axis angular acceleration information obtained by the MPU6050 six-axis sensor. The expression is: Δa x =-k×a x ,Δa y =-k×a y ,Δa z =-k×a z Δβ x =-k×β x ,Δβ y =-k×β y ,Δβ z =-k×β z Among them, Δa x is the target compensation acceleration for the x-axis, Δa y is the target compensation acceleration for the y-axis, Δa z is the target compensation acceleration for the z-axis; Δβ x is the target compensation angular acceleration about the x-axis, Δβ y is the target compensation angular acceleration about the y-axis, Δβ z is the target compensation angular acceleration about the z-axis; k is the space limit coefficient; a x , a y , a z are the vehicle's x, y, and z-axis accelerations respectively; β x , β y , β z are the angular accelerations of the x, y, and z axes of the vehicle, respectively; 22), Calculate the occupant mass m according to the forces detected on the vehicle seat obtained by the pressure sensor; the calculation formula is: Among them, is the force detected by the th pressure sensor, g = 9.8 m / s 2 , and n is the total number of pressure sensors; 23) Calculate the occupant centroid coordinates (x c , y c ) based on the force detected on the vehicle seat obtained by the pressure sensor; the calculation formula is: Among them is the coordinate of the th pressure sensor on the x and y axes; 24) When the coordinates of the occupant's center of mass (x c , y c ) deviate from the geometric center of the seat, the vehicle acceleration generates an additional inertial moment, and the moment calculation formula is: τ x = -m × [a y × z c - a z × y c ​ τ y = -m×[a z ×x c -a x ×z c ​ τ z = -m × [a x × y c - a y × x c ​ Among them, τ x represents the moment about the x-axis; τ y represents the moment about the y-axis; τ z represents the moment about the z-axis; z c represents the z-axis coordinate of the occupant's center of mass; 25) Obtain the final target compensated angular acceleration [Δβ x +δβ x ,Δβ y +δβ y ,Δβ z +δβ y based on the additional inertial torque generated by the vehicle acceleration during centroid offset; the specific process is as follows: The additional inertial torque τ generated by the vehicle acceleration when the centroid is offset x , τ y , τ z , the moment compensation acceleration [δβ x , δβ y , δβ y caused by the centroid offset is obtained and expressed as: where k z is the vertical stiffness coefficient I xx is the moment of inertia of the six-degree-of-freedom motion platform about the x-axis, I yy is the moment of inertia of the six-degree-of-freedom motion platform about the y-axis; Based on the target compensation angular acceleration of the seat [Δβ x , Δβ y , Δβ z , the torque compensation acceleration [δβ x , δβ y , δβ y caused by the centroid offset is superimposed to obtain the final target compensation angular acceleration [Δβ x + δβ x , Δβ y + δβ y , Δβ z + δβ y ; where, Δβ x +δβ x is the final target compensating angular acceleration about the x-axis, and Δβ y +δβ y is the final target compensating angular acceleration about the y-axis, and Δβ z +δβ y is the final target compensating angular acceleration about the z-axis; 26)、 Multiply the final target compensation acceleration of the seat [Δa x , Δa y , Δa z , Δβ x + δβ x , Δβ y + δβ y , Δβ z + δβ y by the compensation intensity coefficient ε, 0 ≤ ε < 100%, to obtain the customized seat target compensation acceleration [εΔa x , εΔa y , εΔa z , ε(Δβ x + δβ x ), ε(Δβ y + δβ y ), δ(Δβ z + δβ y )], and calculate the target length jointly formed by the sleeve and the movable rod of the telescopic sleeve in the parallel mechanism; 27) Real-time detection of the actual length L formed by the i-th sleeve and the movable rod extending out of the sleeve i,实际 ; The specific process is as follows: The actual length L formed by the i-th sleeve and the movable rod extending from the sleeve is detected in real time by a linear encoder built into the electric cylinder i,实际 , and the measurement formula is: where N is the number of encoder pulses, P is the lead of the ball screw built into the electric cylinder, R is the encoder resolution; L 套筒 is the length; 28) Based on the i-th target length L i,目标 and the i-th actual length L i,实际 calculate the i-th closed-loop error; the specific process is as follows: e i (k) = L i,目标 -L i,实际 where e i (k) is the error signal at time k; 29) Calculate the i-th control quantity u i (k) based on the i-th error signal e i (k) ； The specific process is as follows: Among them, Δt′ is the control response time, K p , K i , K d are the PID control coefficients; e i (j) is the error signal at time j, e i (k - 1) is the error signal at time k - 1; 210), convert the i-th control quantity u i (k) into the motor speed command ω m,i , and the motor speed command ω m,i controls the rotation of the motor in the electric cylinder. The motor drives the ball screw to rotate, and the ball screw drives the movable rod to extend and retract. The specific process is as follows: Convert the i-th control quantity u i (k) into the motor speed command ω m,i , and the specific process is as follows: Among them, K v is the motor speed constant, and K t is the motor torque constant; Motor speed command ω m,i Control the rotation of the motor in the electric cylinder. The motor drives the ball screw to rotate, and the ball screw drives the movable rod to extend and retract; The electric cylinder includes a slave controller and a safety redundancy module; The safety redundancy module forcibly locks the six-degree-of-freedom platform when any of the following conditions is triggered; The vehicle is detected to have suffered an abnormal collision; the occupant mass > 150 kg; The motor current ≥ rated current or the temperature ≥ 80 °C; The CAN bus communication is interrupted for more than 200 ms.

9. The control method of a six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation according to claim 8, characterized in that: The final target compensation acceleration of the seat [Δa x , Δa y , Δa z , Δβ x + δβ x , Δβ y + δβ y , Δβ z + δβ y is multiplied by the compensation intensity coefficient ε, 0 ≤ ε < 100%, to obtain the customized seat target compensation acceleration [εΔa x , εΔa y , εΔa z , ε(Δβ x + δβ x ), ε(Δβ y + δβ y ), ε(Δβ z + δβ y ), and the target length jointly formed by the sleeve and the movable rod of the extended sleeve in the parallel mechanism is calculated; The specific process is as follows: 261)、 Multiply the final target compensation acceleration of the seat [Δa x , Δa y , Δa z , Δβ x + δβ x , Δβ y + δβ y , Δβ z + δβ y by the compensation intensity coefficient ε, where 0 ≤ ε < 100%, to obtain the customized seat target compensation acceleration [εΔa x , εΔa y , εΔa z , ε(Δβ x + δβ x ), ε(Δβ y + δβ y ), ε(Δβ z + δβ y )]; Among them, εΔa x The self-defined target compensation acceleration for the x-axis is εΔa y The self-defined target compensation acceleration for the y-axis is εΔa z The self-defined target compensation acceleration for the z-axis is ε(Δβ x +δβ x ) is the self-defined target compensation angular acceleration about the x-axis, ε(Δβ y +δβ y ) is the self-defined target compensation angular acceleration about the y-axis, ε(Δβ z +δβ y ) is the self-defined target compensation angular acceleration about the z-axis; Within the sensor response time Δt, the acceleration and angular acceleration are converted into displacement and angle increments through double integration: Δx = ∫∫εΔa x dt 2 , Δy = ∫∫εΔa y dt 2 , Δz = ∫∫εΔa z dt 2 θ x = ∫∫ε(Δβ x + δβ x )dt 2 , θ y = ∫∫ε(Δβ y + δβ y )dt 2 , θ z = ∫∫ε(Δβ z + δβ z )dt 2 Among them, Δx represents the displacement along the x-axis, Δy represents the displacement along the y-axis, and Δz represents the displacement along the z-axis; θ x represents the x-axis angle increment, θ y represents the y-axis angle increment, θ z represents the z-axis angle increment; 262)、 Calculate the coordinates of the i-th hinge point at the connection between the six-degree-of-freedom motion platform and the seat body based on the displacement Δx along the x-axis, displacement Δy along the y-axis, displacement Δz along the z-axis, and the rotation matrix obtained with angular increments Among them, x B0i represents the initial x - axis coordinate of the i - th hinge point at the connection between the six - degree - of - freedom motion platform and the seat body, y B0i represents the initial y - axis coordinate of the i - th hinge point at the connection between the six - degree - of - freedom motion platform and the seat body, z B0i represents the initial z - axis coordinate of the i - th hinge point at the connection between the six - degree - of - freedom motion platform and the seat body; i = 1, 2,..., 6 x Bi represents the x-axis target coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform and the seat body, y Bi represents the y-axis target coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform and the seat body, z Bi represents the z-axis target coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform and the seat body; i = 1, 2,..., 6; R is the rotation matrix; where, R z (θ z ) represents the rotation matrix corresponding to the z-axis angle increment θ z ; Ry(θy) represents the rotation matrix corresponding to the y-axis angle increment θ y ; and R x (θ x ) represents the rotation matrix corresponding to the x-axis angle increment θ x ; 263) Calculate the target length \(L\) jointly composed of the \(i\)-th sleeve and the movable rod extending from the sleeve based on the hinge point coordinates at the connection between the six-degree-of-freedom motion platform and the seat body, where \(i = 1, 2, \cdots, 6\): i,目标 , \(i = 1, 2, \cdots, 6\): Among them, (x Ai , y Ai , z Ai ) is the coordinate of the i-th hinge point at the connection between the base and the freedom motion platform, where i = 1, 2,..., 6.

10. A control method for a six-degree-of-freedom anti-motion sickness vehicle seat based on occupant mass adaptation according to claim 4, characterized in that: In step two, the horizontal movement degrees of freedom and rotational degrees of freedom are locked, and only vertical vibration compensation is performed; the specific process is as follows: 31) Calculate the target compensation acceleration Δa of the seat z-axis based on the z-axis acceleration information obtained by the MPU6050 six-axis sensor z , and the expression is: Δa z = -k × a z where, Δa z is the target compensation acceleration in the z-axis direction; k is the spatial constraint coefficient; a z is the vehicle z-axis acceleration; 32) During the sensor response time Δt, the z-axis acceleration is converted into displacement Δz = ∫∫Δa z dt 2 ; Among them, Δz represents the displacement along the z-axis; Calculate the z-axis coordinate z of the i-th hinge point at the connection between the six-degree-of-freedom motion platform and the seat body Bi = z B0i + Δz Among them, z Bi represents the z-axis target coordinate of the i-th hinge point at the connection between the six-degree-of-freedom motion platform and the seat body; z B0i represents the initial z-axis coordinate of the i-th hinge point at the connection of the six-degree-of-freedom motion platform seat body; The z-axis coordinate z of the i-th hinge point at the connection between the six-degree-of-freedom motion platform and the seat body Bi , calculate the target length L jointly formed by the i-th sleeve and the movable rod extending out of the sleeve i,目标 , where i = 1, 2,..., 6, which is expressed as: z Ai It is the z-axis coordinate of the i-th hinge point at the connection between the base and the degree-of-freedom motion platform, where i = 1, 2,..., 6; 33) Real-time detection of the actual length L formed by the i-th sleeve and the movable rod extending out of the sleeve i,实际 ; The specific process is as follows: The actual length L formed by the i-th sleeve and the movable rod extending from the sleeve is detected in real time through the linear encoder built into the electric cylinder i,实际 , and the measurement formula is: Where N is the number of encoder pulses, P is the lead of the ball screw built into the electric cylinder, R is the encoder resolution; L 套筒 is the sleeve length; 34), based on the i-th target length L i,目标 and the i-th actual length L i,实际 calculate the i-th closed-loop error; The specific process is as follows: e i (k) = L i,目标 -L i,实际 where e i (k) is the error signal at time k; 35), based on the i-th error signal e i (k), calculate the i-th control quantity u i (k) ； The specific process is as follows: where Δt′ is the control response time, K p , K i , K d are the PID control coefficients; e i (j) is the error signal at time j, e i (k - 1) is the error signal at time k - 1; 36) Convert the i-th control quantity u i (k) into the motor speed command ω m,i , and the motor speed command ω m,i controls the rotation of the motor in the electric cylinder. The motor drives the ball screw to rotate, and the ball screw drives the movable rod to extend and retract. The specific process is as follows: Convert the $i$-th control quantity $u$ i (k) into the motor speed command $\omega$ m,i , and the specific process is as follows: where K v is the motor speed constant, and K t is the motor torque constant; Motor speed command ω m,i Control the rotation of the motor in the electric cylinder. The motor drives the ball screw to rotate, and the ball screw drives the movable rod to expand and contract.

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