阅读说明：本技术 一种白车身弯曲刚度测试方法及系统 (Method and system for testing bending stiffness of body-in-white ) 是由 王一帆 郏超 原孝菊 温敏 怀自力 陈伟 于 2021-09-29 设计创作，主要内容包括：本发明提供一种白车身弯曲刚度测试方法及系统,该方法包括：在白车身的前轴位置和后轴位置分别设置有第一支撑点和第二支撑点,并通过所述第一支撑点和所述第二支撑点对白车身进行固定支撑。对白车身的中间区域施加预定荷载的负荷,使白车身弯曲变形,并获取白车身前轴和后轴的下降位移。根据前轴下降位移和后轴下降位移计算得到白车身弯曲方向的实际位移量,并根据弯曲刚度公式计算得到白车身弯曲刚度。本方法能解决现有白车身弯曲刚度测试结果不精准的问题,能提高车身测试数据的准确性,对于车身设计及试验提供可靠数据。(The invention provides a method and a system for testing the bending rigidity of a body-in-white, wherein the method comprises the following steps: the white car body fixing support device is characterized in that a first supporting point and a second supporting point are respectively arranged at the front shaft position and the rear shaft position of the white car body, and the white car body is fixedly supported through the first supporting point and the second supporting point. A load of a predetermined load is applied to a middle region of the body-in-white to bend and deform the body-in-white, and the lowering displacements of the front and rear axles of the body-in-white are obtained. And calculating the actual displacement in the bending direction of the body-in-white according to the front axle descending displacement and the rear axle descending displacement, and calculating the bending rigidity of the body-in-white according to a bending rigidity formula. The method can solve the problem that the existing white automobile body bending rigidity test result is not accurate, can improve the accuracy of automobile body test data, and provides reliable data for automobile body design and test.)

1. A body-in-white bending stiffness test method is characterized by comprising the following steps:

respectively arranging a first supporting point and a second supporting point at the front shaft position and the rear shaft position of the body-in-white, and fixedly supporting the body-in-white through the first supporting point and the second supporting point;

applying a load of a preset load to the middle area of the body-in-white to enable the body-in-white to bend and deform and obtain the descending displacement of the front axle and the rear axle of the body-in-white;

and calculating the actual displacement in the bending direction of the body-in-white according to the front axle descending displacement and the rear axle descending displacement, and calculating the bending rigidity of the body-in-white according to a bending rigidity formula.

2. The method for testing bending rigidity of a body-in-white according to claim 1, wherein the calculating of the actual displacement amount in the bending direction of the body-in-white according to the front axle lowering displacement and the rear axle lowering displacement comprises:

acquiring a white vehicle body load stress position, and acquiring an X axial distance between the load stress position and a front shaft position or a rear shaft position;

acquiring the X axial distance between the front shaft position and the rear shaft position, the descending displacement of the front shaft position in the Z direction and the descending displacement of the rear shaft position in the Z direction;

constructing a displacement triangle according to the load stress position, the front axis position and the rear axis position of the body-in-white, and calculating according to the displacement triangle to obtain a Z-direction calculated displacement corresponding to the load stress position;

and obtaining a corrected actual displacement according to the Z-direction maximum displacement of the white body load stress position, the Z-direction calculated displacement, the front axle descending displacement and the rear axle descending displacement.

3. The body-in-white bending stiffness test method according to claim 2, further comprising:

if the front axle descending displacement is larger than the rear axle descending displacement, the formula is followedObtaining the calculated displacement quantity delta d in the Z direction, and obtaining the formula d ═ d_max-d₂Δ d, calculating a corrected actual displacement d, wherein d₁Is the descending displacement of the front axis position Z, d₂Is the Z-direction descending displacement of the rear shaft position, X is the X-axis distance between the front shaft position and the rear shaft position, X₁Is the X-axis distance, d, of the load-bearing position from the rear-axis position_maxIs the maximum Z-direction displacement of the white body load stress position.

4. The body-in-white bending stiffness test method according to claim 3, further comprising:

if the descending displacement of the rear axle is greater than that of the front axleMove according to the formulaObtaining the calculated displacement quantity delta d in the Z direction, and obtaining the formula d ═ d_max-d₁Δ d, calculating the corrected actual displacement d.

5. The body-in-white bending stiffness test method according to claim 4, wherein the calculating the body-in-white bending stiffness according to a bending stiffness formula comprises:

according to the formulaAnd calculating the body-in-white bending rigidity K, wherein F is the loading load of the body-in-white.

6. A body-in-white bending stiffness testing system, comprising: the device comprises a first convex support, a second convex support, a load loading device, a displacement sensor and a calculation unit;

the first convex support is used for setting a first support point at the front shaft position of the body in white;

the second convex support is used for arranging a second supporting point at the rear shaft position of the body in white;

the load loading device is used for applying a load of a preset load to the middle area of the body-in-white so as to bend and deform the body-in-white;

the displacement sensor is used for acquiring the descending displacement of a front axle and a rear axle of the body in white;

and the calculation unit is used for calculating the actual displacement in the white automobile body bending direction according to the front axle descending displacement and the rear axle descending displacement and calculating the white automobile body bending rigidity according to a bending rigidity formula.

7. The body-in-white bending stiffness testing system according to claim 6, wherein the calculating unit includes:

the first calculation module is used for calculating the X axial distance between the load stress position of the body-in-white and the front shaft position or the rear shaft position;

the second calculation module is used for calculating the X-axis distance between the front axis position and the rear axis position, the descending displacement of the front axis position in the Z direction and the descending displacement of the rear axis position in the Z direction;

the third calculation module is used for constructing a displacement triangle according to the load stress position, the front axis position and the rear axis position of the body-in-white, and calculating to obtain a Z-direction calculation displacement corresponding to the load stress position according to the displacement triangle;

the fourth calculation module is used for calculating the displacement according to the Z-direction maximum displacement of the white vehicle body load stress position, the Z-direction calculated displacement, the front axle descending displacement and the rear axle descending displacement to obtain the corrected actual displacement;

a fifth calculation module for calculating according to the formulaAnd calculating the body-in-white bending rigidity K, wherein F is the loading load of the body-in-white.

8. The body-in-white bending stiffness testing system according to claim 7, further comprising:

and the first correction unit is used for obtaining a Z-direction calculated displacement delta d according to a formula when the front-axis descending displacement is larger than the rear-axis descending displacement, and calculating a corrected actual displacement d according to the formula, wherein d1 is the descending displacement of the front-axis position in the Z direction, d2 is the descending displacement of the rear-axis position in the Z direction, X is the X axial distance between the front-axis position and the rear-axis position, X1 is the X axial distance between the load bearing position and the rear-axis position, and dmax is the Z-direction maximum displacement of the white vehicle body load bearing position.

9. The body-in-white bending stiffness testing system according to claim 8, further comprising:

a second correcting unit for correcting the lowering displacement of the rear axle to be larger than that of the front axle according to the formulaObtaining the calculated displacement quantity delta d in the Z direction, and obtaining the formula d ═ d_max-d₁Δ d, calculating the corrected actual displacement d.

Technical Field

The invention relates to the technical field of automobile testing, in particular to a method and a system for testing the bending rigidity of a body-in-white.

Background

In the design and production process of automobiles, the rigidity of an automobile body is one of the most important indexes, is the basis of the structure of the whole automobile body, determines the quality and performance of the automobile, and is closely related to the NVH (Noise, Vibration, Harshness), control, reliability, collision safety and the like of the whole automobile. The white body is used as a carrier of the whole vehicle, the NVH performance of the vehicle can be directly reduced due to insufficient rigidity, and the problems of vibration noise such as resonance, dynamic sealing, low-frequency rolling and the like are caused; meanwhile, the vehicle body is greatly deformed during running, the steering problem occurs or the running line cannot be expected, the vehicle is subjectively loose, and therefore the control performance of the vehicle is reduced.

In the existing bending rigidity test of the body-in-white, a servo motor loading mechanism is utilized in the test to apply a load F to the body, and a displacement sensor is used to measure the maximum displacement of a chassis to calculate the bending rigidity. However, the mode does not consider the integral descending displacement of the vehicle body caused by the local deformation of the supporting points of the front and rear axles of the vehicle body in the test loading process, and the actual deflection of the vehicle body is smaller than the maximum displacement measured by the sensor, so that the bending rigidity result of the vehicle body is not accurate.

Disclosure of Invention

The invention provides a white automobile body bending rigidity testing method and system, solves the problem that the existing white automobile body bending rigidity testing result is not accurate, can improve the accuracy of automobile body testing data, and provides reliable data for automobile body design and test.

In order to achieve the above purpose, the invention provides the following technical scheme:

a body-in-white bending stiffness test method comprises the following steps:

respectively arranging a first supporting point and a second supporting point at the front shaft position and the rear shaft position of the body-in-white, and fixedly supporting the body-in-white through the first supporting point and the second supporting point;

applying a load of a preset load to the middle area of the body-in-white to enable the body-in-white to bend and deform and obtain the descending displacement of the front axle and the rear axle of the body-in-white;

and calculating the actual displacement in the bending direction of the body-in-white according to the front axle descending displacement and the rear axle descending displacement, and calculating the bending rigidity of the body-in-white according to a bending rigidity formula.

Preferably, the calculating the actual displacement amount in the body-in-white bending direction according to the front axle lowering displacement and the rear axle lowering displacement includes:

acquiring a white vehicle body load stress position, and acquiring an X axial distance between the load stress position and a front shaft position or a rear shaft position;

acquiring the X axial distance between the front shaft position and the rear shaft position, the descending displacement of the front shaft position in the Z direction and the descending displacement of the rear shaft position in the Z direction;

constructing a displacement triangle according to the load stress position, the front axis position and the rear axis position of the body-in-white, and calculating according to the displacement triangle to obtain a Z-direction calculated displacement corresponding to the load stress position;

and obtaining a corrected actual displacement according to the Z-direction maximum displacement of the white body load stress position, the Z-direction calculated displacement, the front axle descending displacement and the rear axle descending displacement.

Preferably, the method further comprises the following steps:

if the front axle descending displacement is larger than the rear axle descending displacement, the formula is followedObtaining the calculated displacement quantity delta d in the Z direction, and obtaining the formula d ═ d_max-d₂Δ d, calculating a corrected actual displacement d, wherein d₁Is the descending displacement of the front axis position Z, d₂Is the Z-direction descending displacement of the rear shaft position, X is the X-axis distance between the front shaft position and the rear shaft position, X₁Is the X-axis distance, d, of the load-bearing position from the rear-axis position_maxIs the maximum Z-direction displacement of the white body load stress position.

Preferably, the method further comprises the following steps:

if the rear axle descending displacement is larger than the front axle descending displacement, the formula is followedObtaining the calculated displacement quantity delta d in the Z direction, and obtaining the formula d ═ d_max-d₁Δ d, meterThe corrected actual displacement d is calculated.

Preferably, the calculating the body-in-white bending stiffness according to the bending stiffness formula includes:

according to the formulaAnd calculating the body-in-white bending rigidity K, wherein F is the loading load of the body-in-white.

The invention also provides a body-in-white bending stiffness test system, comprising: the device comprises a first convex support, a second convex support, a load loading device, a displacement sensor and a calculation unit;

the first convex support is used for setting a first support point at the front shaft position of the body in white;

the second convex support is used for arranging a second supporting point at the rear shaft position of the body in white;

the load loading device is used for applying a load of a preset load to the middle area of the body-in-white so as to bend and deform the body-in-white;

the displacement sensor is used for acquiring the descending displacement of a front axle and a rear axle of the body in white;

and the calculation unit is used for calculating the actual displacement in the white automobile body bending direction according to the front axle descending displacement and the rear axle descending displacement and calculating the white automobile body bending rigidity according to a bending rigidity formula.

Preferably, the calculation unit includes:

the first calculation module is used for calculating the X axial distance between the load stress position of the body-in-white and the front shaft position or the rear shaft position;

the second calculation module is used for calculating the X-axis distance between the front axis position and the rear axis position, the descending displacement of the front axis position in the Z direction and the descending displacement of the rear axis position in the Z direction;

the third calculation module is used for constructing a displacement triangle according to the load stress position, the front axis position and the rear axis position of the body-in-white, and calculating to obtain a Z-direction calculation displacement corresponding to the load stress position according to the displacement triangle;

the fourth calculation module is used for calculating the displacement according to the Z-direction maximum displacement of the white vehicle body load stress position, the Z-direction calculated displacement, the front axle descending displacement and the rear axle descending displacement to obtain the corrected actual displacement;

a fifth calculation module for calculating according to the formulaAnd calculating the body-in-white bending rigidity K, wherein F is the loading load of the body-in-white.

Preferably, the method further comprises the following steps:

a first correcting unit, for obtaining the Z-direction calculated displacement quantity delta d according to a formula when the front axle descending displacement is larger than the rear axle descending displacement, and calculating to obtain the corrected actual displacement quantity d according to the formula, wherein d₁Is the descending displacement of the front axis position Z, d₂Is the Z-direction descending displacement of the rear shaft position, X is the X-axis distance between the front shaft position and the rear shaft position, X₁Is the X-axis distance, d, of the load-bearing position from the rear-axis position_maxIs the maximum Z-direction displacement of the white body load stress position.

Preferably, the method further comprises the following steps:

a second correcting unit for correcting the lowering displacement of the rear axle to be larger than that of the front axle according to the formulaObtaining the calculated displacement quantity delta d in the Z direction, and obtaining the formula d ═ d_max-d₁Δ d, calculating the corrected actual displacement d.

The invention provides a white vehicle body bending rigidity testing method and a white vehicle body bending rigidity testing system. The problem of current white automobile body bending stiffness test result inaccurate is solved, can improve the accuracy of automobile body test data, provide reliable data to automobile body design and experiment.

Drawings

In order to more clearly describe the specific embodiments of the present invention, the drawings to be used in the embodiments will be briefly described below.

FIG. 1 is a schematic diagram of a body-in-white bending stiffness test method provided by the invention.

FIG. 2 is a schematic diagram of the calculation of the present invention providing a greater front axle roll-off displacement than the rear axle.

FIG. 3 is a schematic diagram of the calculation of the present invention to provide a greater rear axle roll-off displacement than the front axle.

Detailed Description

In order to make the technical field of the invention better understand the scheme of the embodiment of the invention, the embodiment of the invention is further described in detail with reference to the drawings and the implementation mode.

Aiming at the problem that the white automobile body bending rigidity test result of a front automobile is not accurate, the white automobile body bending rigidity test method and the white automobile body bending rigidity test system are provided, support points are arranged at the front shaft position and the rear shaft position of a white automobile body for fixed support, a load is arranged in the middle area of the white automobile body to enable the white automobile body to bend and deform, and then the white automobile body bending rigidity is obtained through calculation according to the front shaft descending displacement and the rear shaft descending displacement. The problem of current white automobile body bending stiffness test result inaccurate is solved, can improve the accuracy of automobile body test data, provide reliable data to automobile body design and experiment.

As shown in fig. 1, a body-in-white bending stiffness test method includes:

s1: the white car body fixing support device is characterized in that a first supporting point and a second supporting point are respectively arranged at the front shaft position and the rear shaft position of the white car body, and the white car body is fixedly supported through the first supporting point and the second supporting point.

S2: a load of a predetermined load is applied to a middle region of the body-in-white to bend and deform the body-in-white, and the lowering displacements of the front and rear axles of the body-in-white are obtained.

S3: and calculating the actual displacement in the bending direction of the body-in-white according to the front axle descending displacement and the rear axle descending displacement, and calculating the bending rigidity of the body-in-white according to a bending rigidity formula.

Specifically, the body-in-white is supported at a front shaft position and a rear shaft position, the body-in-white is supported and fixed at a first supporting point and a second supporting point, and a load person applying a predetermined load in a middle area of the body-in-white is applied through a load loading device, so that the body-in-white is bent and deformed. And detecting the descending displacement of the front shaft position and the rear shaft position after the load is loaded, and calculating according to a bending stiffness formula after detecting the actual displacement of the white body bending. The method can improve the accuracy of the vehicle body test data and provide reliable data for vehicle body design and test.

Further, the calculating the actual displacement amount of the body-in-white in the bending direction according to the front axle descending displacement and the rear axle descending displacement includes:

acquiring a white vehicle body load stress position, and acquiring an X axial distance between the load stress position and a front shaft position or a rear shaft position;

acquiring the X axial distance between the front shaft position and the rear shaft position, the descending displacement of the front shaft position in the Z direction and the descending displacement of the rear shaft position in the Z direction;

constructing a displacement triangle according to the load stress position, the front axis position and the rear axis position of the body-in-white, and calculating according to the displacement triangle to obtain a Z-direction calculated displacement corresponding to the load stress position;

and obtaining a corrected actual displacement according to the Z-direction maximum displacement of the white body load stress position, the Z-direction calculated displacement, the front axle descending displacement and the rear axle descending displacement.

The method further comprises the following steps:

s4: if the front axle descending displacement is larger than the rear axle descending displacement, the formula is followedObtaining the calculated displacement quantity delta d in the Z direction, and obtaining the formula d ═ d_max-d₂Δ d, calculating a corrected actual displacement d, wherein d₁Is the descending displacement of the front axis position Z, d₂Is the Z-direction descending displacement of the rear shaft position, X is the X-axis distance between the front shaft position and the rear shaft position, X₁Is the X-axis distance, d, of the load-bearing position from the rear-axis position_maxIs the maximum Z-direction position of the white body load stress positionAnd (5) moving amount.

S5: if the rear axle descending displacement is larger than the front axle descending displacement, the formula is followedObtaining the calculated displacement quantity delta d in the Z direction, and obtaining the formula d ═ d_max-d₁Δ d, calculating the corrected actual displacement d.

In practical application, a displacement triangle is constructed according to the load-bearing position, the front axis position and the rear axis position of the body-in-white, as shown in fig. 2 and 3, Δ d is calculated according to the shape of the triangle, and then the corrected actual displacement d is obtained. According to the method, the actual displacement can be corrected by calculating the displacement triangle formed after the body-in-white is loaded, the problem that the bending rigidity test result of the existing body-in-white is not accurate can be solved, the accuracy of the vehicle body test data can be improved, and reliable data are provided for vehicle body design and test.

Further, the calculating the body-in-white bending stiffness according to the bending stiffness formula includes: according to the formulaAnd calculating the body-in-white bending rigidity K, wherein F is the loading load of the body-in-white.

The method comprises the steps of arranging support points at the front shaft position and the rear shaft position of the body-in-white for fixed support, arranging load in the middle area of the body-in-white to enable the body-in-white to be bent and deformed, and calculating the bending rigidity of the body-in-white according to the descending displacement of the front shaft and the descending displacement of the rear shaft. The problem of current white automobile body bending stiffness test result inaccurate is solved, can improve the accuracy of automobile body test data, provide reliable data to automobile body design and experiment.

Correspondingly, the invention also provides a body-in-white bending stiffness test system, which comprises: the device comprises a first projection support, a second projection support, a load loading device, a displacement sensor and a calculation unit. The first convex support is used for setting a first support point at the front shaft position of the body in white. The second convex support is used for setting a second support point at the rear axle position of the body in white. The load loading device is used for applying a load of a preset load to the middle area of the body-in-white so as to bend and deform the body-in-white. The displacement sensor is used for acquiring the descending displacement of the front axle and the rear axle of the body in white. And the calculation unit is used for calculating the actual displacement in the white automobile body bending direction according to the front axle descending displacement and the rear axle descending displacement and calculating the white automobile body bending rigidity according to a bending rigidity formula.

The calculation unit includes: the first calculation module is used for calculating the X axial distance between the load stress position of the body-in-white and the front shaft position or the rear shaft position. And the second calculation module is used for the X-axis distance between the front axis position and the rear axis position, the descending displacement of the front axis position in the Z direction and the descending displacement of the rear axis position in the Z direction. And the third calculation module is used for constructing a displacement triangle according to the load stress position, the front axis position and the rear axis position of the body-in-white, so as to calculate and obtain the Z-direction calculated displacement corresponding to the load stress position according to the displacement triangle. And the fourth calculation module is used for calculating the displacement according to the Z-direction maximum displacement of the white body load stress position, the Z-direction calculated displacement, the front axle descending displacement and the rear axle descending displacement to obtain the corrected actual displacement. A fifth calculation module for calculating according to the formulaAnd calculating the body-in-white bending rigidity K, wherein F is the loading load of the body-in-white.

The system further comprises: a first correcting unit, for obtaining the Z-direction calculated displacement quantity delta d according to a formula when the front axle descending displacement is larger than the rear axle descending displacement, and calculating to obtain the corrected actual displacement quantity d according to the formula, wherein d₁Is the descending displacement of the front axis position Z, d₂Is the Z-direction descending displacement of the rear shaft position, X is the X-axis distance between the front shaft position and the rear shaft position, X₁Is the X-axis distance, d, of the load-bearing position from the rear-axis position_maxIs the maximum Z-direction displacement of the white body load stress position.

The system further comprises: a second correcting unit for making the rear axle descending displacement larger than the front axle descending displacementAccording to the formulaObtaining the calculated displacement quantity delta d in the Z direction, and obtaining the formula d ═ d_max-d₁Δ d, calculating the corrected actual displacement d.

The invention provides a white vehicle body bending rigidity testing system, which is characterized in that a first convex support and a second convex support are adopted to fixedly support the position of a front shaft and the position of a rear shaft of a white vehicle body, a load loading device is used for setting a load in the middle area of the white vehicle body to enable the white vehicle body to bend and deform, and a computing unit is used for computing the bending rigidity of the white vehicle body according to the descending displacement of the front shaft and the descending displacement of the rear shaft. The problem of current white automobile body bending stiffness test result inaccurate is solved, can improve the accuracy of automobile body test data, provide reliable data to automobile body design and experiment.

The construction, features and functions of the present invention have been described in detail with reference to the embodiments shown in the drawings, but the present invention is not limited to the embodiments shown in the drawings, and all equivalent embodiments modified or modified by the spirit and scope of the present invention should be protected without departing from the spirit of the present invention.