A bicycle saddle fatigue testing device

Abstract

The present invention relates to the technical field of performance testing, and in particular to a bicycle saddle fatigue testing device. The device adds a posture adjustment module and a pressure module control module on the basis of a traditional saddle fatigue testing device. The rotation shaft structure in the posture adjustment module can change the posture of the saddle base through operation. The pressure module control module takes into account the irreversible deformation of the saddle during the test, determines the time to be controlled by detecting the time when the irreversible deformation occurs, and increases the pressing depth of the pressure module according to the chaos of the surface deformation at the time to be controlled. The present invention can simulate the changes in the center of gravity of the human body during the use of the saddle, improve the reference of the scene simulation, and realize adaptive adjustment of the pressing depth, avoiding the problem of inaccurate test results caused by a relatively small pressing depth.

Description

Technical Field

[0001] The invention relates to the technical field of performance testing, and in particular to a bicycle saddle fatigue testing device. Background Art

[0002] Fatigue testing of bicycle saddles can be used to evaluate the performance of the saddle. The fatigue test uses a mechanical transmission device to perform a large number of pressing operations on the fixed surface of the bicycle saddle, and then evaluates the anti-fatigue performance of the saddle based on the test results. In the existing test device, a pressure module is used to apply pressure to the saddle installed on the base, thereby simulating the scene of a person sitting on the saddle, and at the same time, a driving device is used to make the saddle swing up and down, thereby simulating the bumpy state of the road. However, in actual use scenarios, the force condition of the saddle is also related to the person's movement posture, that is, the existing technology cannot effectively simulate the use scenario, and the tested saddle performance is insufficient for reference. In addition, during the test, the saddle will be irreversibly affected by the pressure, resulting in a change in the height of the saddle. If the pressure module still uses the initially set downward pressure depth to test at this time, it will not be able to fully apply pressure to the saddle, which also results in insufficient reference for the saddle performance test results. Summary of the invention

[0003] In order to solve the technical problems that the existing devices do not accurately simulate the use scenarios of bicycle saddles and the pressing depth of the pressure module is not accurately set, resulting in insufficient reference of the test results, the purpose of the present invention is to provide a bicycle saddle fatigue test device, and the technical solutions adopted are as follows:

[0004] The present invention provides a bicycle saddle fatigue testing device, comprising a saddle base and a pressure module, the device also comprising a posture adjustment module and a pressure module control module; the posture adjustment module is composed of a plurality of rotating shaft structures installed under the saddle base, the rotating shaft structure comprises a rotating shaft and a vertical rotating shaft connecting rod connected to the rotating shaft, the rotating shafts of the rotating shaft structures have different rotation directions, and the posture of the saddle base is changed by the operation of all the rotating shaft structures;

[0005] The pressure module control module is used to determine the deformation correlation condition of the saddle according to the change of the cracking degree of the saddle surface at different times and the change of the saddle height at the same saddle position; determine the time to be controlled according to the deformation correlation condition; at the time to be controlled, increase the pressing depth of the pressure module according to the deformation chaos of the saddle surface.

[0006] Furthermore, the posture adjustment module is composed of three rotating shaft structures, which are evenly spaced along the width direction of the saddle base, wherein the rotating shaft structures on both sides rotate in opposite directions, and the middle rotating shaft structure is fixed relative to the rotating shaft structures on both sides.

[0007] Furthermore, the pressure module control module includes an image acquisition unit, which acquires a saddle surface image and determines the cracking degree according to edge information in the saddle surface image.

[0008] Further, determining the cracking degree according to edge information in the saddle surface image includes:

[0009] The number of edges in the saddle surface image is obtained; the longest edge is selected as the reference edge; according to the angle of the reference edge relative to the width direction of the saddle, the projected crack length of the reference edge in the saddle width direction is obtained; the number of edges is multiplied by the projected crack length to obtain the degree of crack visibility; the ratio of the degree of crack visibility to the area of ​​the saddle region is normalized to obtain the degree of cracking.

[0010] Furthermore, the image acquisition unit also acquires a side image of the saddle, and acquires the saddle height at different saddle positions at each sampling moment according to the side image.

[0011] Furthermore, the method for obtaining the deformation association status includes:

[0012] For each moment, the difference in cracking degree between the current moment and the previous moment is normalized; the saddle height difference at the same saddle position is obtained, and the average saddle height difference at all positions is used as the saddle height change at the current moment. The saddle height change is negatively correlated and normalized to obtain data confidence; the data confidence is multiplied by the normalized cracking degree difference to obtain the deformation correlation status at the current moment.

[0013] Furthermore, the to-be-controlled moment is the moment when the deformation association condition is greater than a preset association condition threshold.

[0014] Further, the step of increasing the applied pressure of the pressure module according to the chaotic deformation of the saddle surface includes:

[0015] The height difference of each position on the saddle surface relative to the standard saddle height is obtained, and the fluctuation characteristics of the height difference between all positions are obtained; an adjustment coefficient is obtained according to the fluctuation characteristics of the height difference, and the pressing depth of the pressure module is increased according to the adjustment coefficient.

[0016] Furthermore, the fluctuation characteristic of the height difference is the standard deviation of the height difference.

[0017] Furthermore, the method in which the pressure module control module increases the pressing depth of the pressure module includes:

[0018] The pressing module is controlled to increase the pressing pressure while keeping the pressing frequency unchanged until the increased pressing depth is reached.

[0019] The present invention has the following beneficial effects:

[0020] The embodiment of the present invention adds a posture adjustment module and a pressure module control module on the basis of a traditional saddle fatigue test device. The rotating shaft structure in the posture adjustment module can change the posture of the saddle base through operation, thereby simulating the change of the center of gravity of the human body during the use of the saddle, thereby improving the reference of the scene simulation. The pressure module control module takes into account the irreversible deformation of the saddle during the test, and determines the time to be controlled by detecting the time when the irreversible deformation occurs, and increases the pressing depth of the pressure module according to the chaos of the surface deformation at the time to be controlled, thereby realizing adaptive adjustment of the pressing depth and avoiding the problem of inaccurate test results caused by a relatively small pressing depth. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0022] Figure 1 A structural diagram of a bicycle saddle fatigue testing device provided by one embodiment of the present invention;

[0023] Figure 2 A flow chart of an execution method of a pressure module control module provided by an embodiment of the present invention;

[0024] Figure 3 A schematic diagram for comparing saddle deformation provided by an embodiment of the present invention.

[0025] In the figure, 1 is a saddle; 2 is a first base bracket; 3 is a second base bracket; 4 is a third base bracket; 5 is a base body; 6 is a first rotating shaft; 7 is a third rotating shaft; 8 is a second rotating shaft; 9 is a first rotating shaft connecting rod; 10 is a third rotating shaft connecting rod; 11 is a second rotating shaft connecting rod. DETAILED DESCRIPTION

[0026] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the specific implementation, structure, features and effects of a bicycle saddle fatigue testing device proposed according to the present invention in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0027] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0028] An embodiment of the present invention provides a bicycle saddle fatigue testing device, which includes a testing device body, wherein the testing device body is the basic module of a traditional saddle fatigue testing device, for example, including a saddle base, a pressure module, etc. The specific structure is a technical means well known to those skilled in the art, and will not be elaborated here. Further, the device also includes a posture adjustment module and a pressure module control module. The posture adjustment module is used to solve the problem of inaccurate simulation of saddle usage scenarios in the prior art, and is composed of multiple rotating shaft structures installed under the saddle base, wherein the rotating shaft structure includes a rotating shaft and a vertical rotating shaft connecting rod connected to the rotating shaft, and the rotation direction of the rotating shaft between different rotating shaft structures is different.

[0029] During riding, the human body movement causes the ischium to have regular impacts on the left and right parts of the saddle. When the rider starts pedaling, the body's center of gravity will shift between the left and right sides as the legs move alternately, and the ischium will also undergo periodic pressure changes on the saddle accordingly. For example, when the rider steps on the left pedal, the ischium will concentrate its force on the left side, exerting greater pressure on the left side of the saddle. As the body's center of gravity shifts and the leg movements change, the ischium will quickly transfer its force to the right side, exerting the same pressure on the right side of the saddle. Through periodic pedaling, the saddle is subjected to the same periodic pressure. Therefore, the bicycle saddle fatigue testing device proposed in the embodiment of the present invention can change the posture of the saddle base by operating multiple rotating shaft structures in the posture adjustment module and utilizing different rotation directions of the rotating shafts, thereby simulating the pressure changes on the saddle in actual scenarios, so that the final test results have sufficient reference value.

[0030] Preferably, in one embodiment of the present invention, the posture adjustment module is composed of three rotating shaft structures, and the three rotating shaft structures are evenly spaced along the width direction of the saddle base, wherein the rotating shaft structures on both sides rotate in opposite directions, and the middle rotating shaft structure is fixed relative to the rotating shaft structures on both sides. That is, during the operation of the rotating shaft structure, if the rotating shaft on one side drives the rotating shaft connecting rod to move upward, the rotating shaft on the other side will drive the rotating shaft connecting rod to move downward, causing the saddle base to tilt, and the middle rotating shaft structure plays a supporting role, thereby causing the saddle to present different pressures at different positions. The operation of the posture adjustment module can realize the continuous change of the posture of the saddle base, so that regular pressure changes occur on the saddle. Please refer to Figure 1 , which shows a structural diagram of a bicycle saddle fatigue testing device provided by an embodiment of the present invention, comprising Figure 1 As shown, the saddle base is composed of a base body 5, a first base bracket 2, a second base bracket 3 and a third base bracket 4. The saddle 1 is fixed on the saddle base. It should be noted that Figure 1 The perspective of the saddle 1 in the figure is the rear perspective of the saddle, that is, the lateral direction under the current perspective is the width direction of the saddle, and the length direction of the saddle is the direction of the narrow part of the saddle from the wide part of the carton. The three rotating shaft structures of the posture adjustment module are evenly spaced along the width direction of the saddle base, such as Figure 1 As shown, the first rotating shaft 6 and the first rotating shaft connecting rod 9 constitute the first rotating shaft structure, the second rotating shaft 8 and the second rotating shaft connecting rod 11 constitute the second rotating shaft structure, and the third rotating shaft 7 and the third rotating shaft connecting rod 10 constitute the third rotating shaft structure. The first rotating shaft structure and the second rotating shaft structure are distributed on both sides of the saddle base, and the regular posture control of the saddle base is realized through opposite rotating shaft directions; the third rotating shaft structure is located in the middle of the saddle base and plays a supporting function. It should be noted that in the embodiment of the present invention, the three rotating shafts are evenly spaced along the width direction of the saddle base and installed at the midpoint position in the length direction, so that the posture of the saddle base can be changed smoothly during operation. When the vertical first rotating shaft connecting rod 9 controls the first rotating shaft 6 to pull down and rotate, the third rotating shaft connecting rod 10 controls the third rotating shaft 7 to rise and rotate, so that the saddle base is tilted unilaterally with the second rotating shaft 8 as the fulcrum, that is, the left side is low and the right side is high. By continuously rotating, the saddle base can be controlled to simulate the left and right center of gravity changes of human body movement, resulting in changes in the pressure of the ischium on the left and right sides of the saddle. It should be noted that, although the second rotating shaft structure is fixed relative to the other two rotating shaft structures, the second rotating shaft 8 also has a rotation function, and a small rotation of the second rotating shaft connecting rod 11 on the second rotating shaft 8 can simulate the bumpy conditions under actual road conditions.

[0031] It should be noted that the pressure module applies vertical pressure above the saddle, because it is a mechanical structure well known to those skilled in the art. Figure 1 Not shown in the figure.

[0032] The bicycle saddle fatigue testing device proposed in the embodiment of the present invention also includes a pressure module control module. Taking into account the situation that the saddle will be locally deformed after being regularly pressured, and the local deformation will cause the height of the saddle to become lower, the original pressing depth of the pressure module cannot fully press down the saddle, that is, relatively speaking, the original pressing depth is shallow. When the pressing depth is shallow, it cannot fully simulate the strong and continuous impact of the ischium on the saddle during actual riding, thereby making the final test result inaccurate. Therefore, it is necessary to adaptively increase the pressing depth of the pressure module according to the specific situation of the saddle during the test, so that the entire test process is more in line with the force changes of the saddle during actual use, and the saddle performance can be more effectively detected. Please refer to Figure 2 , which shows a flow chart of an execution method of a pressure module control module provided by an embodiment of the present invention, the method comprising:

[0033] Step S1: Determine the deformation correlation status of the saddle according to the change of the cracking degree of the saddle surface at different times and the change of the saddle height at the same saddle position.

[0034] If the saddle is permanently deformed, it will inevitably cause cracks on the saddle surface. For a moment, if the current moment has a more obvious cracking degree than the previous moment, it means that the current moment is more likely to be the moment when the saddle is permanently deformed. Further considering that there is a pressure module above the saddle to apply pressure, if it is significantly deformed, it will be reflected that the height of the saddle changes. Because the posture of the saddle base is constantly changing, the height changes at different positions on the saddle surface are different. Please refer to Figure 3 , which shows a saddle deformation comparison diagram provided by an embodiment of the present invention, Figure 3 The horizontal axis is the saddle width, and the vertical axis is the saddle height. By comparing the standard saddle height curve and the actual saddle height curve on the coordinate system, it can be seen that if the saddle is deformed, the actual saddle height has different height performances at different positions relative to the standard saddle height. Therefore, it is necessary to analyze the changes in the saddle height at different times at each saddle position. If the change in saddle height is significantly correlated with the change in cracking degree, for example, the change in cracking degree is stronger than the change in saddle height, it means that although the saddle has rebounded at this time, it still causes relatively obvious irreversible damage. Therefore, the deformation correlation status can be obtained first. The more obvious the deformation correlation status is, the more likely it is that irreversible deformation has occurred at the current moment, and the pressing depth of the pressure module needs to be adjusted.

[0035] Step S2: determining a time to be controlled according to the deformation correlation status; at the time to be controlled, increasing the pressing depth of the pressure module according to the deformation disorder of the saddle surface.

[0036] The control time can be determined in time according to the deformation correlation status. At the control time, the more chaotic the deformation distribution of the saddle surface is, the more irreversible deformation has occurred at some positions on the saddle surface. If the original pressing depth is maintained, the pressing depth of this part will be smaller than that of other parts, resulting in poor test results. Therefore, at the control time, the pressing depth of the pressure module needs to be increased according to the chaotic deformation of the saddle surface.

[0037] Preferably, in one embodiment of the present invention, the pressure module control module includes an image acquisition unit, which acquires a saddle surface image and determines the degree of cracking according to edge information in the saddle surface image. In one embodiment of the present invention, the edge information is acquired by a canny edge detection operator, and the image acquisition unit acquires images using a camera, the camera is deployed at an angle above the saddle, and image information is acquired once a minute.

[0038] Furthermore, in one embodiment of the present invention, if cracks occur on the surface of the saddle, obvious crack information will appear, and the obviousness of the crack information can be reflected by the number and length. And due to the position and special shape of the saddle during the test process, the shear force in the width direction is an important reason for the cracking of the saddle, so the crack information in the width direction can better reflect the cracking of the saddle surface. Therefore, the cracking degree is determined according to the edge information in the saddle surface image, including:

[0039] The number of edges in the saddle surface image is obtained, that is, the more the number of edges, the more obvious the cracking of the surface.

[0040] Select the longest edge as the reference edge. According to the angle of the reference edge relative to the width direction of the saddle, obtain the projected crack length of the reference edge in the width direction of the saddle. That is, take the longest edge as a reference to obtain the projected crack length in the width direction. The larger the projected crack length, the more obvious the crack. Therefore, multiply the number of edges by the projected crack length to obtain the degree of crack visibility.

[0041] Further combined with the saddle area, the saddle area was used as the basic data, and the ratio of the crack visibility to the saddle area was normalized to obtain the cracking degree.

[0042] It should be noted that, in one embodiment of the present invention, the reference edge relative to the saddle width direction can be obtained by linearly fitting the reference edge using the least square method, and the angle between the fitting line and the saddle width direction is used as the angle between the reference edge and the saddle width direction. The normalization operation is normalized using range normalization.

[0043] It should be noted that, because there are calculations between different dimensions in the embodiments of the present invention, the corresponding data needs to be dimensionless before the calculation, otherwise the dimension will have an impact on the calculation. The dimensionless processing process can adopt standardization or normalization operations, which are technical means well known to those skilled in the art and will not be described in detail here.

[0044] Preferably, in one embodiment of the present invention, the image acquisition unit also acquires a side image of the saddle, and obtains the saddle height at different saddle positions at each sampling moment according to the side image. In the embodiment of the present invention, the image acquisition unit acquires the saddle height through a camera installed on the side of the saddle.

[0045] Preferably, in one embodiment of the present invention, a method for acquiring deformation association status includes:

[0046] For each moment, the difference in cracking degree between the current moment and the previous moment is normalized. The saddle height difference at the same saddle position is obtained. Since there are saddle height differences at multiple positions, the average saddle height difference at all positions is taken as the saddle height change at the current moment. The saddle height change is negatively correlated and normalized to obtain the data confidence; the data confidence is multiplied by the normalized cracking degree difference to obtain the deformation correlation status at the current moment. Because the data confidence is the result of negative correlation mapping and normalization of the saddle height change, the larger the product of the data confidence and the normalized cracking degree difference, the more obvious the change in the cracking degree is, and the more likely this moment is the moment when irreversible deformation occurs.

[0047] In one embodiment of the present invention, the saddle height change is negatively correlated using the inverse method. In order to prevent the denominator from being 0, a coefficient needs to be added to the denominator, that is, the inverse of the sum of the saddle height change and a preset coefficient is used as the data confidence. The preset coefficient is set to 1.

[0048] In one embodiment of the present invention, 25 position points are evenly arranged in the width direction of the side surface of the saddle as sampling points for calculating the saddle height.

[0049] Preferably, in one embodiment of the present invention, the to-be-controlled moment is the moment when the deformation association condition is greater than a preset association condition threshold. In the embodiment of the present invention, after the deformation association condition is normalized, the association condition threshold is set to 0.84.

[0050] Preferably, in one embodiment of the present invention, increasing the applied pressure of the pressure applying module according to the chaotic deformation of the saddle surface includes:

[0051] The height difference of each position on the saddle surface relative to the standard saddle height is obtained, and the fluctuation characteristics of the height difference between all positions are obtained. The adjustment coefficient is obtained according to the fluctuation characteristics of the height difference, and the pressing depth of the pressure module is increased according to the adjustment coefficient. That is, the larger the fluctuation characteristics, the larger the adjustment coefficient, and the larger the pressing depth that needs to be increased.

[0052] In one embodiment of the present invention, the adjustment coefficient is obtained by normalizing the fluctuation characteristics and adding the positive integer 1. Since the adjustment coefficient is a number between 1 and 2, the increased depression depth can be obtained by directly multiplying the adjustment coefficient by the original depression depth.

[0053] Preferably, in one embodiment of the present invention, the method in which the pressure module control module increases the pressing depth of the pressure module comprises:

[0054] The pressing module is controlled to increase the pressing pressure while keeping the pressing frequency unchanged until the increased pressing depth is reached.

[0055] In summary, the embodiment of the present invention adds a posture adjustment module and a pressure module control module on the basis of the traditional saddle fatigue testing device. The rotating shaft structure in the posture adjustment module can change the posture of the saddle base through operation, thereby simulating the change of the center of gravity of the human body during the use of the saddle, thereby improving the reference of the scene simulation. The pressure module control module takes into account the irreversible deformation of the saddle during the test, and determines the time to be controlled by detecting the moment when the irreversible deformation occurs, and increases the pressing depth of the pressure module according to the chaos of the surface deformation at the time to be controlled, thereby realizing adaptive adjustment of the pressing depth and avoiding the problem of inaccurate test results caused by relatively small pressing depth.

[0056] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying 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.

[0057] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A bicycle saddle fatigue testing device, comprising a saddle base and a pressure module, characterized in that: The device also includes a posture adjustment module and a pressure module control module; the posture adjustment module is composed of a plurality of rotating shaft structures installed under the saddle base, the rotating shaft structure includes a rotating shaft and a vertical rotating shaft connecting rod connected to the rotating shaft, the rotating shafts of the rotating shaft structures have different rotation directions, and the posture of the saddle base is changed by the operation of all the rotating shaft structures; The pressure module control module is used to determine the deformation correlation status of the saddle according to the changes in the cracking degree of the saddle surface at different times and the changes in the saddle height at the same saddle position; determine the time to be controlled according to the deformation correlation status; at the time to be controlled, increase the pressing depth of the pressure module according to the deformation chaos of the saddle surface; The method for obtaining the deformation association status includes: For each moment, the difference in cracking degree between the current moment and the previous moment is normalized; the saddle height difference at the same saddle position is obtained, and the average saddle height difference at all positions is used as the saddle height change at the current moment. The saddle height change is negatively correlated and normalized to obtain data confidence; the data confidence is multiplied by the normalized cracking degree difference to obtain the deformation correlation status at the current moment.

2. A bicycle saddle fatigue testing device according to claim 1, characterized in that: The posture adjustment module is composed of three rotating shaft structures, which are evenly spaced along the width direction of the saddle base, wherein the rotating shaft structures on both sides rotate in opposite directions, and the middle rotating shaft structure is fixed relative to the rotating shaft structures on both sides.

3. A bicycle saddle fatigue testing device according to claim 1, characterized in that: The pressure module control module includes an image acquisition unit, which acquires a saddle surface image and determines the cracking degree according to edge information in the saddle surface image.

4. A bicycle saddle fatigue testing device according to claim 3, characterized in that: Determining the cracking degree according to edge information in the saddle surface image includes: The number of edges in the saddle surface image is obtained; the longest edge is selected as the reference edge; according to the angle of the reference edge relative to the width direction of the saddle, the projected crack length of the reference edge in the saddle width direction is obtained; the number of edges is multiplied by the projected crack length to obtain the degree of crack visibility; the ratio of the degree of crack visibility to the area of ​​the saddle region is normalized to obtain the degree of cracking.

5. A bicycle saddle fatigue testing device according to claim 3, characterized in that: The image acquisition unit also acquires a side image of the saddle, and acquires the saddle height at different saddle positions at each sampling moment according to the side image.

6. A bicycle saddle fatigue testing device according to claim 1, characterized in that: The to-be-controlled moment is the moment when the deformation association condition is greater than a preset association condition threshold.

7. A bicycle saddle fatigue testing device according to claim 1, characterized in that: The step of increasing the applied pressure of the pressure module according to the chaotic deformation of the saddle surface comprises: The height difference of each position on the saddle surface relative to the standard saddle height is obtained, and the fluctuation characteristics of the height difference between all positions are obtained; an adjustment coefficient is obtained according to the fluctuation characteristics of the height difference, and the pressing depth of the pressure module is increased according to the adjustment coefficient.

8. A bicycle saddle fatigue testing device according to claim 7, characterized in that: The fluctuation characteristic of the height difference is the standard deviation of the height difference.

9. A bicycle saddle fatigue testing device according to claim 1 or 7, characterized in that: The method by which the pressure module control module increases the pressing depth of the pressure module comprises: The pressing module is controlled to increase the pressing pressure while keeping the pressing frequency unchanged until the increased pressing depth is reached.

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