Method and device for measuring head motion trail of test object in automobile driving

Abstract

The embodiment of the invention discloses a method and a device for measuring the head motion trail of a test object in automobile driving. The method comprises the following steps: determining a rotation matrix at each moment corresponding to angular velocity data by acquiring head test data of a target test object, and then translating the angular velocity data and relative acceleration data to obtain the head centroid acceleration of the target test object; and correcting the head centroid acceleration based on the gravity factor to obtain absolute acceleration, and finally performing integral operation on the absolute acceleration based on an integral algorithm to obtain a head movement track of the target test object. The sampling data is combined with the head mass center and the gravity factor to be converted into the head movement track curve under the global coordinate system, so that the requirements that the measuring point coincides with the head mass center point of the target test object and the influence of gravitational acceleration is eliminated are met, and relatively accurate head displacement track calculation of the target test object is realized; and the effectiveness and the accuracy of virtual evaluation are ensured.

Description

Technical Field

[0001] One or more embodiments of the present specification relate to the field of intelligent automobile technology, and more particularly, to a method and device for measuring the movement trajectory of a test subject's head while a car is driving. Background Art

[0002] With the rapid development of smart car technology, in car driving tests, the deviation trajectory of the test object's head is extremely critical in testing experiments such as judging the head injury value. At present, the traditional method for solving the test object's head motion trajectory is generally to first obtain the absolute acceleration of the test object's head, and directly integrate the absolute acceleration of the test object's head to obtain the test object's head motion trajectory. However, the absolute acceleration obtained by this method generally includes the influence of gravity acceleration, and it cannot be guaranteed that the absolute acceleration measurement point coincides with the target test object's head center of mass point, so that the final test object trajectory curve is greatly different from the actual curve, which affects subsequent test experiments and cannot meet high-precision requirements. Summary of the invention

[0003] The embodiment of this specification provides a method and device for measuring the head motion trajectory of a test subject while a car is driving, and the technical solution is as follows:

[0004] In a first aspect, an embodiment of the present specification provides a method for measuring a head motion trajectory of a test subject while a car is driving, the method comprising:

[0005] Acquire head test data of the target test object, and determine the rotation matrix at each moment corresponding to the angular velocity data based on the angle change method, wherein the head test data includes angular velocity data and relative acceleration data;

[0006] The angular velocity data and the relative acceleration data are translated based on the point coincidence to obtain the head center of mass acceleration of the target test object, wherein the point coincidence is the coincidence between the measurement point of the head test data and the head center of mass of the target test object;

[0007] Correcting the acceleration of the center of mass of the head based on the gravity factor and the rotation matrix at each moment to obtain an absolute acceleration;

[0008] The absolute acceleration is integrated based on an integration algorithm, and the integration results are integrated to obtain the head movement trajectory of the target test object.

[0009] In a second aspect, a device for measuring the head movement trajectory of a test subject while a car is driving is provided, the device comprising:

[0010] An acquisition module is used to acquire head test data of a target test object and determine the rotation matrix at each moment corresponding to the angular velocity data based on an angle change method, wherein the head test data includes angular velocity data and relative acceleration data;

[0011] A translation module, used for performing translation processing on the angular velocity data and the relative acceleration data based on point coincidence to obtain the head center of mass acceleration of the target test object, wherein the point coincidence is the coincidence between the measurement point of the head test data and the head center of mass of the target test object;

[0012] A correction module, used for correcting the acceleration of the center of mass of the head based on the gravity factor and the rotation matrix at each moment to obtain an absolute acceleration;

[0013] The integration module is used to perform an integration operation on the absolute acceleration based on an integration algorithm, and integrate the integration operation results to obtain the head movement trajectory of the target test object.

[0014] In a third aspect, an electronic device is provided, including a device processor and a memory;

[0015] The device processor is connected to the memory;

[0016] The memory is used to store executable program code;

[0017] The device processor runs a program corresponding to the executable program code by reading the executable program code stored in the memory, so as to execute the steps of the method provided in the first aspect or any possible implementation manner of the first aspect.

[0018] In a fourth aspect, a computer-readable storage medium is provided, on which a computer program is stored, and the computer-readable storage medium stores instructions, which, when the instructions are executed on a computer or a device processor, cause the computer or the device processor to execute the method provided in the first aspect or any possible implementation of the first aspect.

[0019] The beneficial effects brought by the technical solutions provided by some embodiments of this specification include at least:

[0020] In one or more embodiments of the present specification, the rotation matrix corresponding to the angular velocity data at each moment is first determined by obtaining the head test data of the target test object, and then the angular velocity data and the relative acceleration data are translated to obtain the head center of mass acceleration of the target test object, and the head center of mass acceleration is corrected based on the gravity factor to obtain the absolute acceleration, and finally the absolute acceleration is integrated based on the integral algorithm to obtain the head motion trajectory of the target test object. By converting the sampled data into a head motion trajectory curve in the global coordinate system in combination with the head center of mass and the gravity factor, the requirements of coinciding the measurement point with the head center of mass of the target test object and eliminating the influence of gravity acceleration are met, and a relatively accurate calculation of the displacement trajectory of the head of the target test object is achieved, ensuring the effectiveness and accuracy of the virtual assessment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A schematic diagram of the system architecture of a method for measuring the head motion trajectory of a test subject while a car is driving, provided in an embodiment of this specification;

[0023] Figure 2 A flow chart of a method for measuring the head motion trajectory of a test subject while a car is driving provided in an embodiment of this specification;

[0024] Figure 3 A schematic diagram of the structure of a device for measuring the head motion trajectory of a test subject while a car is driving, provided in an embodiment of this specification;

[0025] Figure 4 A schematic diagram of the structure of an electronic device provided in an embodiment of this specification. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0027] The terms "first", "second", "third", etc. in the description and claims of this specification and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0028] The following description provides examples and does not limit the scope, applicability or examples set forth in the claims. Changes may be made to the functions and arrangements of the elements described without departing from the scope of the present specification. Various processes or components may be appropriately omitted, substituted or added to each example. For example, the described method may be performed in an order different from the order described, and various steps may be added, omitted or combined. In addition, features described with respect to some examples may be combined in other examples.

[0029] See also Figure 1 , Figure 1 A schematic diagram of the system architecture of a method for measuring the head motion trajectory of a test subject while a car is driving, provided in an embodiment of this specification.

[0030] like Figure 1 As shown, the system architecture of the method for measuring the head motion trajectory of a test subject while a car is driving may include at least a terminal 10 , a server 20 and a network 30 .

[0031] The terminal 10 includes but is not limited to electronic devices such as smart phones, desktop computers, tablet computers, laptops, smart speakers, digital assistants, smart wearable devices, etc., and may also be software running on the above electronic devices, such as applications, etc. Optionally, the operating system running on the electronic device may include but is not limited to Android system, IOS system, Linux, Windows, etc. Optionally, the terminal 10 provides a head motion trajectory measurement service to the user, and the terminal 10 may obtain a head motion trajectory measurement instruction of an application program interface, and send a head motion trajectory measurement request to the server 20.

[0032] The server 20 can provide background services for the terminal 10. According to the head motion trajectory measurement request sent by the terminal 10, the server 20 will obtain a series of head motion trajectory measurement instructions, and the server 20 transmits the head motion trajectory measurement instructions to other terminals 10 through the network 30. Specifically, the server 20 can be an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN (Content Delivery Network), and big data and artificial intelligence platforms.

[0033] The network 30 is used to provide a medium for a communication link between the terminal 10 and the server 20. The network 30 may include various connection types, such as wired or wireless communication links or optical fiber cables.

[0034] In addition, it should be noted that Figure 1 What is shown is only one system provided by the present disclosure. In practical applications, other systems may also be included, for example, more terminals may be included.

[0035] In the embodiments of the present specification, the terminal 10 and the server 20 may be directly or indirectly connected via wired or wireless communication, which is not limited in the present disclosure.

[0036] See next Figure 2 , Figure 2 The overall flow chart of a method for measuring the head motion trajectory of a test subject while a car is driving provided by an embodiment of the present specification is shown. The method for measuring the head motion trajectory of a test subject while a car is driving can be used in the server 20.

[0037] like Figure 2 As shown, the method for measuring the head motion trajectory of a test subject while the car is driving may at least include the following steps:

[0038] Step 201: Acquire head test data of the target test object, and determine the rotation matrix at each moment corresponding to the angular velocity data based on the angle change method.

[0039] Wherein, the head test data includes angular velocity data and relative acceleration data.

[0040] In the embodiment of the present specification, when the target test of automobile driving is performed, the target test object can wear an inertial measurement unit and other data acquisition equipment to collect the head test data of the target test object. Among them, the head test data may include angular velocity data and relative acceleration data. Optionally, in order to reduce the impact of noise on the collected data, a low-pass filter can be used to filter the collected angular velocity and relative acceleration data. Then, the initial rotation matrix in the initial state is first determined by the angle change method, and then the angle change is obtained by the angular velocity data, and the corresponding rotation matrix is ​​constructed according to the angle change. Further, starting from the initial test moment, for each time interval, the rotation matrix of the target at the next moment can be obtained by cross-multiplying the rotation matrix of the previous moment with the moment angle change of the current moment. Through the above change steps, the rotation matrix of each moment corresponding to the angular velocity data at each moment can be obtained.

[0041] In one possible implementation manner, before determining the rotation matrix at each moment corresponding to the angular velocity data based on the angle change method, the method further includes:

[0042] Determine a first sampling frequency corresponding to the angular velocity data and a second sampling frequency corresponding to the relative acceleration data in the head test data;

[0043] The degree of consistency between the first sampling frequency and the second sampling frequency is determined, and the validity of the head test data is determined based on the determination result.

[0044] In the embodiment of the present specification, after the angular velocity data and relative acceleration data of the target test object are acquired, since the angular velocity and relative acceleration are not collected at the same time, the first sampling frequency corresponding to the angular velocity data and the second sampling frequency corresponding to the relative acceleration data in the head test data are first determined by reading the data file time. Optionally, first check whether the first sampling frequency and the second sampling frequency meet the minimum sampling frequency requirement. Then, determine the frequency consistency of the first sampling frequency and the second sampling frequency, that is, whether the sampling frequency and duration of the data file are consistent. When the judgment result is characterized by the frequency consistency of the first sampling frequency and the second sampling frequency meeting the requirements, it is determined that the acquired head test data is valid, and subsequent data processing steps can be performed. When the judgment result is characterized by the frequency consistency of the first sampling frequency and the second sampling frequency not meeting the requirements, it is determined that the acquired head test data is invalid, and the data is sampled and judged again, and the subsequent data processing steps are not performed.

[0045] In one possible implementation, the determining of the rotation matrix at each moment corresponding to the angular velocity data based on the angle change method includes:

[0046] Integrate the angular velocity data of the target test object at each moment to obtain the angle change at that moment;

[0047] The angle variation at each moment is converted based on the angle matrix cross multiplication method to obtain the rotation matrix at each moment.

[0048] In the embodiment of this specification, after obtaining the angular velocity data of the target test object, the angular velocity data of the target test object at each moment can be integrated to obtain the angle change corresponding to each moment. Then, the angle change at each moment is converted by angle matrix cross multiplication. The format of the rotation matrix can be set as follows:

[0049]

[0050] Among them, α, β, and γ represent the yaw angle, pitch angle, and roll angle of the target test object at the corresponding moment. When calculating the rotation matrix at the next moment, the rotation matrix of the previous moment can be cross-multiplied by the corresponding moment angle change. Through the above change steps, the rotation matrix at each moment can be obtained.

[0051] Step 202: performing translation processing on the angular velocity data and the relative acceleration data based on the point coincidence to obtain the head center of mass acceleration of the target test object.

[0052] The point coincidence degree is the coincidence degree between the measurement point of the head test data and the head centroid point of the target test object.

[0053] In the embodiments of the present specification, the installation position of the acquisition sensor on the head of the target test object, that is, the measurement point position, can be determined first, and then the center of mass position of the target test object's head can be determined through a geometric model or biometric data. Then, the distance between the measurement point and the center of mass of the head can be calculated to obtain the degree of overlap between the two. If the point overlap represents that the two points just completely overlap, no translation processing is required. If the obtained point overlap represents that the two points do not overlap, it is necessary to first calculate the difference in coordinates between the two points, and translate the relative acceleration corresponding to the measurement point in combination with the angular velocity data and the coordinate difference in the global coordinate system to obtain the acceleration of the center of mass of the head of the target test object.

[0054] In one possible implementation, the angular velocity data and the relative acceleration data are translated based on the point coincidence to obtain the head center of mass acceleration of the target test object, including:

[0055] Determine the degree of coincidence between the measurement points of the head test data and the head centroid point of the target test object based on a coordinate calculation method;

[0056] Based on the overlap, the angular velocity data and the relative acceleration data are subjected to relative point translation processing to obtain the head center of mass acceleration of the target test object.

[0057] In the embodiment of this specification, the installation position coordinates of the acquisition sensor on the target test object's head, that is, the measurement point position coordinates, are first determined, and then the center of mass position coordinates of the target test object's head are determined through a geometric model or biometric data, and the coincidence between the measurement point and the head center of mass is determined based on the coordinate calculation method through the measurement point position coordinates and the center of mass position coordinates. Further, the head center of mass acceleration of the target test object = relative acceleration at the measurement point + ω 2 R, where ω is the angular velocity and R is the vector from the measurement point to the center of mass. The specific calculation method is:

[0058]

[0059] where a COG_x , a COG_y , a COG_z are the accelerations in the X, Y, and Z directions at the center of mass; a x , a y , a z are the accelerations in the X, Y, and Z directions measured at the measuring point; ω x ,ω y ,ω z are the angular velocities around the X, Y, and Z axes respectively; Δx, Δy, and Δz are the differences between the X, Y, and Z coordinates of the point where the acceleration is measured and the center of mass.

[0060] Step 203: Correct the head center of mass acceleration based on the gravity factor and the rotation matrix at each moment to obtain an absolute acceleration.

[0061] In the embodiments of this specification, in order to eliminate the influence of gravity acceleration, it is necessary to ensure that the acceleration measurement value does not contain the component caused by the earth's gravity. Optionally, the gravity acceleration component is first separated from the center of mass acceleration by the gravity factor, and the center of mass acceleration of the head is corrected by gravity separation. Then, the corrected acceleration is transformed by the obtained rotation matrix at each moment to obtain the absolute acceleration.

[0062] In one possible implementation, the correction processing of the head center of mass acceleration based on the gravity factor and the rotation matrix at each moment to obtain the absolute acceleration includes:

[0063] Correcting the head center of mass acceleration based on the gravity factor to obtain a corrected acceleration;

[0064] The correction acceleration is converted into a coordinate system based on the rotation matrix at each moment to obtain an absolute acceleration in a global coordinate system.

[0065] In the embodiments of this specification, the tilt angle of the center of mass of the head of the target test object can be determined based on the gravity factor, which may include the pitch angle and roll angle of the center of mass of the head. Then, the acceleration of the center of mass of the head is corrected by the tilt angle to obtain the corrected acceleration. Furthermore, the corrected acceleration can be directly converted to coordinates by calling the scipy library function of Python, inputting the corrected acceleration and the rotation matrix corresponding to each moment, and obtaining the absolute acceleration in the global coordinate system.

[0066] In one possible implementation, the correcting the head center of mass acceleration based on the gravity factor to obtain the corrected acceleration includes:

[0067] Obtaining the tilt angle of the center of mass of the head of the target test object relative to the direction of gravity, and determining the gravity acceleration component corresponding to the tilt angle based on the gravity factor;

[0068] A gravity separation correction is performed on the head center of mass acceleration based on the gravity acceleration component to obtain a corrected acceleration.

[0069] In the embodiment of the present specification, when the head center of mass acceleration is corrected by the gravity factor, the pitch angle and roll angle of the head center of mass of the target test object relative to the gravity direction can be determined first during the test, and then the gravity acceleration component corresponding to the tilt angle can be determined by the gravity factor g. Then, the head center of mass acceleration is corrected for gravity separation by the gravity acceleration component to obtain the corrected acceleration.

[0070] Among them, the specific calculation formula of the corrected acceleration is:

[0071]

[0072] where a ′ x , a ′ y , a ′ z is the corrected acceleration after acceleration correction, The three elements of the third row of the rotation matrix at the current moment; The three elements of the third row of the rotation matrix at the initial moment. Describes the component of the z-axis in the x-axis direction after rotation; Describes the component of the z-axis in the y-axis direction after rotation; It describes the component of the z-axis in the z-axis direction after the rotation, because when the z-axis rotates itself, its component on the z-axis remains unchanged and is usually close to 1.

[0073] Step 204: perform an integration operation on the absolute acceleration based on an integration algorithm, and integrate the integration operation results to obtain the head movement trajectory of the target test object.

[0074] In the embodiment of this specification, after obtaining the absolute acceleration of the target object to be measured, the absolute acceleration can be integrated twice by an integral algorithm. The specific calculation method is:

[0075] v1=v0+dv

[0076] s1=s0+(v+0.5dv)dt

[0077] Among them, v0 is the speed at the previous moment, v1 is the speed at the next moment, and dv is the speed change; s0 is the displacement at the previous moment, s1 is the displacement at the next moment, and ds is the displacement change. Through two integrations, we can get the absolute displacement list in the three directions of X, Y, and Z. Furthermore, by marking the coordinate system points of the absolute displacement at all moments, we can get the head movement trajectory of the target test object.

[0078] In one possible implementation, the step of performing an integration operation on the absolute acceleration based on an integration algorithm and integrating the integration operation results to obtain the head motion trajectory of the target test object includes:

[0079] Performing acceleration integration operation on the absolute acceleration based on a trapezoidal integration algorithm to obtain velocity data;

[0080] Performing velocity integration operation on the velocity data to obtain displacement data at each moment in the global coordinate system;

[0081] The displacement coordinate points of the displacement data at each moment are integrated to obtain the head movement trajectory of the target test object.

[0082] In the embodiments of this specification, the absolute acceleration data can be first converted into velocity data by a trapezoidal integration algorithm, and the integration time interval can be set to be the same as the sampling interval of the acceleration sampling data, and then the acceleration data of each time interval can be subjected to a trapezoidal integration operation to obtain velocity data. Next, the velocity data is subjected to a velocity integration operation to obtain the displacement data of the target test object's head in the global coordinate system. Finally, the displacement data obtained at each moment is integrated according to the time sequence of the displacement coordinate points to obtain the head motion trajectory of the target test object.

[0083] The above is a description of a specific embodiment of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0084] See next Figure 3 , Figure 3 The schematic diagram of the structure of a device for measuring the head movement trajectory of a test subject in a driving car provided in an embodiment of the present specification is shown. It should be noted that: Figure 3 The device for measuring the head movement trajectory of a test subject in a moving car is used to implement the present application. Figure 2 For the convenience of explanation, only the part related to the embodiment of the present application is shown. For the specific technical details not disclosed, please refer to the present application. Figure 2 The embodiment shown.

[0085] like Figure 3 As shown, the device for measuring the head motion trajectory of a test subject during driving of a car may at least include:

[0086] An acquisition module 301 is used to acquire head test data of a target test object and determine the rotation matrix at each moment corresponding to the angular velocity data based on an angle change method, wherein the head test data includes angular velocity data and relative acceleration data;

[0087] A translation module 302 is used to perform translation processing on the angular velocity data and the relative acceleration data based on point coincidence to obtain the head center of mass acceleration of the target test object, wherein the point coincidence is the coincidence between the measurement point of the head test data and the head center of mass of the target test object;

[0088] A correction module 303, used for correcting the acceleration of the head center of mass based on the gravity factor and the rotation matrix at each moment to obtain an absolute acceleration;

[0089] The integration module 304 is used to perform an integration operation on the absolute acceleration based on an integration algorithm, and integrate the integration operation results to obtain the head movement trajectory of the target test object.

[0090] In one possible implementation, the acquisition module 301 is specifically used for:

[0091] Determine a first sampling frequency corresponding to the angular velocity data and a second sampling frequency corresponding to the relative acceleration data in the head test data;

[0092] The degree of consistency between the first sampling frequency and the second sampling frequency is determined, and the validity of the head test data is determined based on the determination result.

[0093] In one possible implementation, the acquisition module 301 is further specifically used for:

[0094] Integrate the angular velocity data of the target test object at each moment to obtain the angle change at that moment;

[0095] The angle variation at each moment is converted based on the angle matrix cross multiplication method to obtain the rotation matrix at each moment.

[0096] In one possible implementation, the translation module 302 is specifically used for:

[0097] Determine the degree of coincidence between the measurement points of the head test data and the head centroid point of the target test object based on a coordinate calculation method;

[0098] Based on the overlap, the angular velocity data and the relative acceleration data are subjected to relative point translation processing to obtain the head center of mass acceleration of the target test object.

[0099] In one possible implementation, the correction module 303 is specifically used to:

[0100] Correcting the head center of mass acceleration based on the gravity factor to obtain a corrected acceleration;

[0101] The correction acceleration is converted into a coordinate system based on the rotation matrix at each moment to obtain an absolute acceleration in a global coordinate system.

[0102] In one possible implementation, the correction module 303 is further configured to:

[0103] Obtaining the tilt angle of the center of mass of the head of the target test object relative to the direction of gravity, and determining the gravity acceleration component corresponding to the tilt angle based on the gravity factor;

[0104] A gravity separation correction is performed on the head center of mass acceleration based on the gravity acceleration component to obtain a corrected acceleration.

[0105] In one possible implementation, the integration module 304 is specifically used for:

[0106] Performing acceleration integration operation on the absolute acceleration based on a trapezoidal integration algorithm to obtain velocity data;

[0107] Performing velocity integration operation on the velocity data to obtain displacement data at each moment in the global coordinate system;

[0108] The displacement coordinate points of the displacement data at each moment are integrated to obtain the head movement trajectory of the target test object.

[0109] Those skilled in the art can clearly understand that the technical solutions of the embodiments of the present application can be implemented with the help of software and / or hardware. The "unit" and "module" in this specification refer to software and / or hardware that can independently complete or cooperate with other components to complete specific functions, where the hardware can be, for example, a field programmable gate array (Field-Programmable Gate Array, FPGA), an integrated circuit (Integrated Circuit, IC), etc.

[0110] Each processing unit and / or module of the embodiments of the present application may be realized by an analog circuit that implements the functions described in the embodiments of the present application, or may be realized by software that executes the functions described in the embodiments of the present application.

[0111] See next Figure 4 , Figure 4 A schematic diagram of the structure of an electronic device provided in an embodiment of this specification is shown.

[0112] like Figure 4 As shown, the electronic device 400 may include: at least one device processor 401 , at least one network interface 404 , a user interface 403 , a memory 405 , and at least one communication bus 402 .

[0113] The communication bus 402 may be used to realize the connection and communication among the above-mentioned components.

[0114] The user interface 403 may include buttons, and the optional user interface may also include a standard wired interface or a wireless interface.

[0115] The network interface 404 may include, but is not limited to, a Bluetooth module, an NFC module, a Wi-Fi module, etc.

[0116] Among them, the device processor 401 may include one or more processing cores. The device processor 401 uses various interfaces and lines to connect various parts within the entire electronic device 400, and executes various functions and processes data of the electronic device 400 by running or executing instructions, programs, code sets or instruction sets stored in the memory 405, and calling data stored in the memory 405. Optionally, the device processor 401 can be implemented in at least one hardware form of DSP, FPGA, and PLA. The device processor 401 can integrate one or a combination of CPU, GPU, modem, etc. Among them, the CPU mainly processes the operating system, user interface, and application programs; the GPU is responsible for rendering and drawing the content to be displayed on the display screen; the modem is used to handle wireless communications. It can be understood that the above-mentioned modem may not be integrated into the device processor 401, and it can be implemented separately through a chip.

[0117] The memory 405 may include RAM or ROM. Optionally, the memory 405 includes a non-transitory computer-readable medium. The memory 405 can be used to store instructions, programs, codes, code sets or instruction sets. The memory 405 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above-mentioned method embodiments, etc.; the data storage area may store data involved in the above-mentioned method embodiments, etc. The memory 405 may optionally be at least one storage device located away from the aforementioned device processor 401. As Figure 4 As shown, the memory 405 as a computer storage medium may include an operating system, a network communication module, a user interface module, and program instructions.

[0118] Specifically, the device processor 401 may be used to call the application for measuring the head motion trajectory of the test subject while the car is driving stored in the memory 405, and specifically perform the following operations:

[0119] Acquire head test data of the target test object, and determine the rotation matrix at each moment corresponding to the angular velocity data based on the angle change method, wherein the head test data includes angular velocity data and relative acceleration data;

[0120] The angular velocity data and the relative acceleration data are translated based on the point coincidence to obtain the head center of mass acceleration of the target test object, wherein the point coincidence is the coincidence between the measurement point of the head test data and the head center of mass of the target test object;

[0121] Correcting the acceleration of the center of mass of the head based on the gravity factor and the rotation matrix at each moment to obtain an absolute acceleration;

[0122] The absolute acceleration is integrated based on an integration algorithm, and the integration results are integrated to obtain the head movement trajectory of the target test object.

[0123] As an optional embodiment of this specification, before determining the rotation matrix at each moment corresponding to the angular velocity data based on the angle change method, the method further includes:

[0124] Determine a first sampling frequency corresponding to the angular velocity data and a second sampling frequency corresponding to the relative acceleration data in the head test data;

[0125] The degree of consistency between the first sampling frequency and the second sampling frequency is determined, and the validity of the head test data is determined based on the determination result.

[0126] As an option of the embodiment of this specification, the method of determining the rotation matrix at each moment corresponding to the angular velocity data based on the angle change method includes:

[0127] Integrate the angular velocity data of the target test object at each moment to obtain the angle change at that moment;

[0128] The angle variation at each moment is converted based on the angle matrix cross multiplication method to obtain the rotation matrix at each moment.

[0129] As an optional embodiment of this specification, the angular velocity data and the relative acceleration data are translated based on the point coincidence to obtain the head center of mass acceleration of the target test object, including:

[0130] Determine the degree of coincidence between the measurement points of the head test data and the head centroid point of the target test object based on a coordinate calculation method;

[0131] Based on the overlap, the angular velocity data and the relative acceleration data are subjected to relative point translation processing to obtain the head center of mass acceleration of the target test object.

[0132] As an optional embodiment of this specification, the correction processing of the head center of mass acceleration based on the gravity factor and the rotation matrix at each moment to obtain the absolute acceleration includes:

[0133] Correcting the head center of mass acceleration based on the gravity factor to obtain a corrected acceleration;

[0134] The correction acceleration is converted into a coordinate system based on the rotation matrix at each moment to obtain an absolute acceleration in a global coordinate system.

[0135] As an option of the embodiment of this specification, the correcting the head center of mass acceleration based on the gravity factor to obtain the corrected acceleration includes:

[0136] Obtaining the tilt angle of the center of mass of the head of the target test object relative to the direction of gravity, and determining the gravity acceleration component corresponding to the tilt angle based on the gravity factor;

[0137] A gravity separation correction is performed on the head center of mass acceleration based on the gravity acceleration component to obtain a corrected acceleration.

[0138] As an option of the embodiment of this specification, the absolute acceleration is integrated based on the integration algorithm, and the integration result is integrated to obtain the head movement trajectory of the target test object, including:

[0139] Performing acceleration integration operation on the absolute acceleration based on a trapezoidal integration algorithm to obtain velocity data;

[0140] Performing velocity integration operation on the velocity data to obtain displacement data at each moment in the global coordinate system;

[0141] The displacement coordinate points of the displacement data at each moment are integrated to obtain the head movement trajectory of the target test object.

[0142] The embodiments of this specification also provide a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the steps of the above method are implemented. The computer-readable storage medium may include, but is not limited to, any type of disk, including a floppy disk, an optical disk, a DVD, a CD-ROM, a micro drive, and a magneto-optical disk, a ROM, a RAM, an EPROM, an EEPROM, a DRAM, a VRAM, a flash memory device, a magnetic card or an optical card, a nanosystem (including a molecular memory IC), or any type of medium or device suitable for storing instructions and / or data.

[0143] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0144] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0145] In the several embodiments provided in the present application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are only schematic, such as the division of the units, which is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some service interfaces, and the indirect coupling or communication connection of devices or units can be electrical or other forms.

[0146] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0147] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0148] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a memory, including a number of instructions to enable a computer device (which can be a personal computer, server or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned memory includes: U disk, read-only memory (ROM), random access memory (RAM), mobile hard disk, disk or optical disk and other media that can store program code.

[0149] A person skilled in the art may understand that all or part of the steps in the various methods of the above embodiments may be completed by entering a program to instruct related hardware, and the program may be stored in a computer-readable memory, which may include a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0150] The above is a description of a specific embodiment of the specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

Claims

1. A method for measuring the head motion trajectory of a test subject while a car is driving, characterized in that: The method comprises: Acquire head test data of the target test object, and determine the rotation matrix at each moment corresponding to the angular velocity data based on the angle change method, wherein the head test data includes angular velocity data and relative acceleration data; The angular velocity data and the relative acceleration data are translated based on the point coincidence to obtain the head center of mass acceleration of the target test object, wherein the point coincidence is the coincidence between the measurement point of the head test data and the head center of mass of the target test object; Correcting the acceleration of the center of mass of the head based on the gravity factor and the rotation matrix at each moment to obtain an absolute acceleration; The absolute acceleration is integrated based on an integration algorithm, and the integration results are integrated to obtain the head movement trajectory of the target test object.

2. The method according to claim 1, characterized in that Before determining the rotation matrix at each moment corresponding to the angular velocity data based on the angle change method, the method further includes: Determine a first sampling frequency corresponding to the angular velocity data and a second sampling frequency corresponding to the relative acceleration data in the head test data; The degree of consistency between the first sampling frequency and the second sampling frequency is determined, and the validity of the head test data is determined based on the determination result.

3. The method according to claim 1, characterized in that The method of determining the rotation matrix at each moment corresponding to the angular velocity data based on the angle change method includes: Integrate the angular velocity data of the target test object at each moment to obtain the angle change at that moment; The angle variation at each moment is converted based on the angle matrix cross multiplication method to obtain the rotation matrix at each moment.

4. The method according to claim 1, characterized in that: The step of performing translation processing on the angular velocity data and the relative acceleration data based on the point coincidence to obtain the head center of mass acceleration of the target test object includes: Determine the degree of coincidence between the measurement points of the head test data and the head center of mass of the target test object based on a coordinate calculation method; Based on the overlap, the angular velocity data and the relative acceleration data are subjected to relative point translation processing to obtain the head center of mass acceleration of the target test object.

5. The method according to claim 1, characterized in that: The correction processing of the head center of mass acceleration based on the gravity factor and the rotation matrix at each moment to obtain the absolute acceleration includes: Correcting the head center of mass acceleration based on the gravity factor to obtain a corrected acceleration; The correction acceleration is converted into a coordinate system based on the rotation matrix at each moment to obtain an absolute acceleration in a global coordinate system.

6. The method according to claim 5, characterized in that The step of correcting the head center of mass acceleration based on the gravity factor to obtain a corrected acceleration includes: Obtaining the tilt angle of the center of mass of the head of the target test object relative to the direction of gravity, and determining the gravity acceleration component corresponding to the tilt angle based on the gravity factor; A gravity separation correction is performed on the head center of mass acceleration based on the gravity acceleration component to obtain a corrected acceleration.

7. The method according to claim 1, characterized in that The step of performing an integration operation on the absolute acceleration based on an integration algorithm and integrating the integration operation results to obtain the head movement trajectory of the target test object includes: Performing acceleration integration operation on the absolute acceleration based on a trapezoidal integration algorithm to obtain velocity data; Performing velocity integration operation on the velocity data to obtain displacement data at each moment in the global coordinate system; The displacement coordinate points of the displacement data at each moment are integrated to obtain the head movement trajectory of the target test object.

8. A device for measuring the head movement trajectory of a test subject while a car is driving, characterized in that: The device comprises: An acquisition module is used to acquire head test data of a target test object and determine the rotation matrix at each moment corresponding to the angular velocity data based on an angle change method, wherein the head test data includes angular velocity data and relative acceleration data; A translation module, used for performing translation processing on the angular velocity data and the relative acceleration data based on point coincidence to obtain the head center of mass acceleration of the target test object, wherein the point coincidence is the coincidence between the measurement point of the head test data and the head center of mass of the target test object; A correction module, used for correcting the acceleration of the center of mass of the head based on the gravity factor and the rotation matrix at each moment to obtain an absolute acceleration; The integration module is used to perform an integration operation on the absolute acceleration based on an integration algorithm, and integrate the integration operation results to obtain the head movement trajectory of the target test object.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, wherein the computer-readable storage medium has instructions stored therein, and when the instructions are executed on a computer or a processor, the computer or the processor executes the steps of the method according to any one of claims 1 to 7.

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