A transverse force coefficient test system measurement method and device

Abstract

The present invention provides a method and device for measuring a lateral force coefficient test system, the method comprising the following steps: a standard lateral force coefficient test system measures the standard lateral force coefficients of a plurality of different standard parts; a plurality of different standard parts are laid on a road surface; a lateral force coefficient test system to be calibrated dynamically measures the lateral force coefficient measurement value of the standard parts; the lateral force coefficient measurement value is compared with the standard lateral force coefficient; according to the measurement error between the lateral force coefficient measurement value and the standard lateral force coefficient, the lateral force coefficient test system is adjusted, and the above steps are repeated until the measurement error between the lateral force coefficient measurement value and the standard lateral force coefficient is within a specified error range. In the method, the measured standard parts are laid on a road surface, providing sufficient space for the dynamic measurement of the lateral force test system to be calibrated, the lateral force coefficient test system to be calibrated dynamically passes through the standard parts, and the lateral force coefficient measurement value under the dynamic condition of the standard parts is measured.

Description

Technical Field

[0001] The invention relates to the technical field of road lateral force coefficient measurement, and in particular to a lateral force coefficient test system measurement method and a measurement device. Background Art

[0002] The skid resistance of the road surface is related to the road driving safety. Currently, there are many types of testing equipment for the skid resistance of the road surface, and the most commonly used indicator is the lateral force coefficient (SFC). When measuring the lateral force coefficient, in order to make the test results of the skid resistance of the road surface more consistent with the most unfavorable state of the vehicle when driving on the road, the test system requires a water supply device to continuously spray a certain amount of clean water at the test track position of the test wheel, so that the tested road surface always maintains a certain water film. The vehicle drives at a constant speed along the normal driving track at a certain test speed. The ratio of the force generated by the road surface on the test wheel to the force in the vertical direction is the lateral force coefficient.

[0003] Commonly used lateral force coefficient test systems include SCRIM system and Mu-meter system.

[0004] However, after the system has been used for a certain period of time, the measurement results of the lateral force will no longer be accurate and need to be verified and calibrated. The verification or calibration agency only verifies or calibrates individual components of the system, and can only reflect the measurement value of the equipment under the static simulation state in the laboratory. It cannot reflect the accuracy of the dynamic measurement results of the equipment under normal driving conditions on site, which makes the traceability of measurement values ​​difficult. In actual projects, the accurate measurement and reliable evaluation of road skid resistance indicators cannot be guaranteed. Summary of the invention

[0005] The invention provides a transverse force coefficient test system measurement method, which solves the technical problem that the transverse force test system can only be statically calibrated and verified in a laboratory and cannot reflect the dynamic measurement results on site.

[0006] Specifically, the lateral force coefficient test system measurement method includes the following steps:

[0007] The standard lateral force coefficient test system measures the standard lateral force coefficients of multiple different standard parts;

[0008] Multiple different standard parts are laid on the road surface;

[0009] The lateral force coefficient test system to be calibrated dynamically measures the measured value of the lateral force coefficient of the standard part;

[0010] The measured value of the lateral force coefficient is compared with the standard lateral force coefficient to obtain the measurement error;

[0011] According to the measurement error between the measured value of the lateral force coefficient and the standard lateral force coefficient, adjust the lateral force coefficient test system and repeat the above steps until the measurement error between the measured value of the lateral force coefficient and the standard lateral force coefficient is within the specified error range.

[0012] Furthermore, the standard lateral force coefficient test system measures the standard lateral force coefficients of multiple different standard parts, specifically including:

[0013] The standard parts are laid on the conveyor belt, and the test wheels of the standard lateral force coefficient test system are placed on the standard parts;

[0014] The load measurement module is placed under the test wheel of the standard lateral force coefficient test system, and the counterweight of the test wheel of the standard lateral force coefficient test system is adjusted so that the load measured by the load measurement module is the standard load;

[0015] Adjusting the ambient temperature, the linear speed of the conveyor belt, and the water supply of the water supply module so that the ambient temperature, the relative speed between the test wheel and the conveyor belt, and the water supply are consistent with the calibration environment;

[0016] Use the standard lateral force coefficient test system to measure the standard lateral force coefficient of the standard part;

[0017] Repeat the above steps to complete the standard lateral force coefficient measurement of multiple standard parts with different levels of anti-slip performance.

[0018] Furthermore, when measuring the standard lateral force coefficient of the standard part, the standard lateral force coefficient measurement of the same standard part is repeated five times. Among the five sets of data obtained, the maximum value and the minimum value are removed, and the average value of the remaining three sets of data is taken, which is the standard lateral force coefficient.

[0019] Furthermore, the laying length of the standard part is not less than twice the circumference of the test wheel of the standard lateral force coefficient test system.

[0020] Furthermore, the lateral force coefficient test system to be calibrated dynamically measures the lateral force coefficient measurement value of the standard part, including:

[0021] Adjust the speed of the lateral force coefficient test system to be calibrated to ensure that the speed is uniform;

[0022] The test wheel of the lateral force coefficient test system to be calibrated passes the standard part in a straight line at a uniform speed to obtain the measured value of the lateral force coefficient;

[0023] Repeat the above steps to obtain multiple groups of lateral force coefficient measurement values, and take the average value, which is the lateral force coefficient measurement value of the standard part.

[0024] The embodiment of the present application further provides a lateral force coefficient test system measuring device, comprising:

[0025] Conveyor belt and standard lateral force coefficient test system, the test wheel of the standard lateral force coefficient test system is placed above the conveyor belt;

[0026] A load measuring module, the load measuring module is located below the conveyor belt where the test wheel contacts the conveyor belt, and the load measuring module provides a supporting force for the test wheel and measures the supporting force;

[0027] The water supply module sprays water to the contact point between the test wheel of the standard lateral force coefficient test system and the conveyor belt, and measures the water flow rate.

[0028] Furthermore, it also includes:

[0029] A conveyor belt control module, which controls the running state of the conveyor belt;

[0030] Speed ​​measurement module, the speed measurement module measures the linear speed of the conveyor belt;

[0031] Temperature measurement module,The temperature measurement module measures the ambient temperature.

[0032] Furthermore, it also includes:

[0033] A control module, the control module is connected with a temperature measurement module, a speed measurement module, a water supply module and a standard lateral force coefficient test system;

[0034] The data processing module is connected to the control module and processes the data collected by the control module.

[0035] Furthermore, the surface of the conveyor belt is paved with standard parts, and the standard parts and the transmission belt are detachably fixed together.

[0036] Furthermore, different standard parts are laid at intervals on the conveyor belt.

[0037] Furthermore, the conveyor belt control module is connected to the pulley of the conveyor belt, and the conveyor belt control module controls the rotation speed of the pulley.

[0038] Furthermore, the control module is electrically connected to the conveyor belt control module, and the conveyor belt control module transmits the running line speed signal of the conveyor belt to the control module.

[0039] It can be seen from the above technical solutions that the beneficial effects of the present invention are:

[0040] 1. The standard lateral force coefficient test system is used to measure the standard lateral force coefficients of multiple different standard parts. The obtained standard lateral force coefficient has high accuracy and is used as a criterion for judging the subsequent lateral force coefficients, so that the calibrated lateral force coefficient test system also has relatively higher accuracy;

[0041] 2. The accuracy of the standard parts, as the intermediate medium of calibration, affects the calibration accuracy of the lateral force coefficient test system. The standard parts measured in this application are laid on the road surface, providing sufficient space for the dynamic measurement of the lateral force test system to be calibrated. The lateral force coefficient test system to be calibrated dynamically passes through the standard parts, and the lateral force coefficient measurement value of the standard parts is measured. The lateral force coefficient measurement value is obtained under dynamic conditions, and thus can reflect the overall dynamic performance of the lateral force coefficient test system to be calibrated;

[0042] 3. Compare the measured value of the lateral force coefficient with the standard lateral force coefficient, and repeatedly debug the lateral force coefficient test system to be calibrated until the measurement result of the lateral force coefficient test system to be calibrated is within the specified error range. In this way, the accuracy of the lateral force coefficient test system to be calibrated is guaranteed, and the accuracy of the lateral force coefficient test system to be calibrated is high and meets the measurement requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The following drawings are only used to schematically illustrate and explain the present invention, and do not limit the scope of the present invention.

[0044] Figure 1 This is a flow chart of a measurement method for a lateral force coefficient testing system according to an embodiment of the present invention.

[0045] Figure 2 It is a schematic diagram of the structure of a metering device for a lateral force coefficient testing system according to an embodiment of the present invention.

[0046] Figure 3 Schematic diagram of standard parts of an embodiment of the present invention.

[0047] Among them: 1- temperature measurement module, 2- speed measurement module, 3- standard lateral force coefficient test system, 4- water supply module, 5- load measurement module, 6- conveyor belt control module, 7- conveyor belt, 8- control module, 9- data processing module. DETAILED DESCRIPTION

[0048] In order to have a clearer understanding of the technical features, purposes and effects of the invention, the specific embodiments of the invention are now described with reference to the accompanying drawings, in which the same reference numerals represent the same parts.

[0049] In this document, “exemplary” means “serving as an example, instance or illustration”, and any diagram or implementation described in this document as “exemplary” should not be interpreted as a more preferred or more advantageous technical solution.

[0050] In order to simplify the drawings, only the parts related to the present invention are schematically shown in each figure, and do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked.

[0051] In this document, “upper”, “lower”, “front”, “back”, “left”, “right”, etc. are only used to indicate the relative position relationship between related parts, rather than to limit the absolute positions of these related parts.

[0052] In this article, "first", "second", etc. are only used to distinguish each other, and do not indicate the importance and order, or the premise of each other's existence.

[0053] In this article, "equal", "same" and the like are not strictly limited in the mathematical and / or geometric sense, but also include errors that can be understood by those skilled in the art and are allowed in manufacturing or use. Unless otherwise specified, the numerical ranges herein include not only the entire range within its two endpoints, but also several sub-ranges contained therein.

[0054] In order to solve the technical problems in the prior art, an embodiment of the present invention provides a lateral force coefficient test system measurement method, such as Figure 1 As shown, the measurement method includes the following steps:

[0055] S1: The standard lateral force coefficient test system 3 measures the lateral force coefficients of a plurality of different standard parts, namely the standard lateral force coefficients;

[0056] S2: Multiple standard parts with different levels of skid resistance are laid on the road surface;

[0057] S3: The lateral force coefficient test system to be calibrated dynamically passes through the standard part, and measures the lateral force coefficient of the standard part, which is the measured value of the lateral force coefficient;

[0058] S4: Compare the measured value of the lateral force coefficient with the standard lateral force coefficient to obtain the measurement error between the measured value of the lateral force coefficient and the standard lateral force coefficient;

[0059] S5: Adjust the lateral force coefficient test system and repeat steps S3 and S4 until the measurement error between the measured lateral force coefficient value and the standard lateral force coefficient is within the specified error range.

[0060] In the prior art, the calibration system only verifies or calibrates individual components of the lateral force coefficient test system in the laboratory, and can only reflect the measured value of the equipment under static simulation conditions, and cannot measure the entire equipment on site, and therefore cannot reflect the accuracy of the dynamic measurement results of the entire equipment under normal driving conditions, resulting in inaccurate measurements. In the metrology method of the present application, a standard lateral force coefficient test system 3 is used to measure the standard lateral force coefficients of multiple different standard parts. The obtained standard lateral force coefficient has high accuracy and is used as a criterion for judgment to evaluate subsequent lateral force coefficients, so that the calibrated lateral force coefficient test system also has relatively higher accuracy; the standard parts serve as an intermediate medium for calibration, and their accuracy affects the calibration accuracy of the lateral force coefficient test system. The standard parts measured in the present application are laid on the on-site road surface, providing sufficient space for the dynamic measurement of the lateral force test system to be calibrated. The lateral force coefficient test system to be calibrated dynamically passes through the standard parts, and the standard is measured. The lateral force coefficient measurement value of the component is obtained under dynamic conditions, and thus can reflect the overall dynamic performance of the lateral force coefficient test system to be calibrated; the lateral force coefficient measurement value is compared with the standard lateral force coefficient, and the lateral force coefficient test system to be calibrated is repeatedly debugged until the measurement result of the lateral force coefficient test system to be calibrated is within the specified error range. In this way, the system can be calibrated on site, which saves time and manpower for system transportation and reduces cost expenditure, while ensuring the accuracy of the lateral force coefficient test system to be calibrated, so that the accuracy of the lateral force coefficient test system to be calibrated is high and meets the measurement requirements.

[0061] More specifically, step S1 specifically includes:

[0062] S101: The standard part is laid on the conveyor belt 7, and the test wheel of the standard lateral force coefficient test system 3 is placed on the standard part;

[0063] S102: The load measurement module 5 is placed under the test wheel of the standard lateral force coefficient test system 3, and the counterweight of the test wheel of the standard lateral force coefficient test system 3 is adjusted so that the load measured by the load measurement module 5 is the standard load;

[0064] S103: adjusting the ambient temperature, the linear speed of the conveyor belt 7 and the water supply of the water supply module 4 so that these parameters are consistent with the parameters of the calibration environment;

[0065] S104: using the standard lateral force coefficient test system 3 to measure the standard lateral force coefficient of the standard component;

[0066] S105: Repeat the above steps to complete the measurement of standard lateral force coefficients of multiple standard parts with different levels of anti-slip performance.

[0067] The above steps ensure that the measurement environment of the standard parts is standard, that is, all environmental factors such as load, temperature, linear speed, water supply, etc. are set artificially. On the one hand, it ensures that the performance of the standard parts is stable and the surface sliding performance will not change due to environmental changes. On the other hand, only when the environmental factors are consistent with the calibration state, the measured value is standard and comparable. If the environment changes, the standard value of the measured standard parts is not standard, and there is no way to perform subsequent calibration. Even if subsequent calibration is performed, the calibration result obtained is inaccurate.

[0068] It is understandable that in order to increase the accuracy of the measurement results, the number of standard parts is selected to be no less than four, and multiple standard parts are measured. When one of the standard parts has a large measurement error, the other standard parts can be used as references to provide a basis for the calibration personnel.

[0069] And, preferably, the standard lateral force coefficient determination of the same standard part in step S104 should be repeated at least five times, and the maximum and minimum values ​​are removed from the five sets of data obtained. It can be understood that multiple measurements can reduce measurement errors. The errors of the maximum and minimum values ​​are the largest. The maximum and minimum values ​​are removed, and the average value of the remaining three sets of data is taken, which is the standard lateral force coefficient, thereby improving the accuracy of the measurement.

[0070] More specifically, in step S2, the laying length of the standard part is not less than twice the circumference of the test wheel of the standard lateral force coefficient test system 3. It can be understood that, since the lateral force coefficient test system to be calibrated in step S3 is dynamically passing through the standard part, if the laying length of the standard part is too short, the lateral force coefficient test system to be calibrated is likely to pass through the standard part in the case of unstable driving or deviation, and the measurement error is large at this time, resulting in inaccurate measurement results of the lateral force coefficient test system to be calibrated, and the lateral force coefficient test system to be calibrated cannot be adjusted based on the measurement results.

[0071] In the embodiment of the present application, step S3 specifically includes:

[0072] S301: adjusting the speed of the lateral force coefficient test system to be calibrated to ensure that the speed is uniform;

[0073] S302: The test wheel of the lateral force coefficient test system to be calibrated passes the standard part in a straight line at a uniform speed to obtain a measured value of the lateral force coefficient;

[0074] S303: Repeat the above steps to obtain multiple groups of lateral force coefficient measurement values, and take the average value, which is the lateral force coefficient measurement value of the standard component.

[0075] Since the measured values ​​obtained by the lateral force coefficient test system to be calibrated are different when the driving state is different, in order to ensure the accuracy of the measurement results, the lateral force coefficient test system to be calibrated is in a uniform and straight driving state, and the driving speed is kept the same each time, so that the measured values ​​each time can be used as references to each other, and the measured values ​​with large errors can be removed to improve the accuracy of the system measurement.

[0076] According to an embodiment of the present application, the measured value of the lateral force coefficient in step S4 is compared with the standard lateral force coefficient to obtain the measurement error between the measured value of the lateral force coefficient and the standard lateral force coefficient. Since there are multiple standard parts, there will also be multiple measured errors. In practice, the maximum value of multiple measurement errors can be taken as the final error, which is the reference error for system calibration.

[0077] To implement the above-mentioned measurement method, the embodiment of the present application further provides a lateral force coefficient test system measurement device, which is applied to the above-mentioned step S1, such as Figure 1 As shown, the metering device includes:

[0078] A conveyor belt 7 and a standard lateral force coefficient test system 3, wherein a test wheel of the standard lateral force coefficient test system 3 is placed above the conveyor belt 7;

[0079] A load measuring module 5, the load measuring module 5 is located below the conveyor belt 7 where the test wheel contacts the conveyor belt 7, and the load measuring module 5 provides a supporting force for the test wheel and measures the supporting force;

[0080] The water supply module 4 sprays water to the contact point between the test wheel of the standard lateral force coefficient test system 3 and the conveyor belt 7, and measures the water flow rate.

[0081] The system uses a water supply module 4 to spray water on the contact point between the test wheel of the standard lateral force coefficient test system 3 and the conveyor belt 7, simulating the actual state during the measurement of the lateral force coefficient of the actual road surface, so that the measured standard value is consistent with the lateral force coefficient measured under actual measurement conditions.

[0082] Furthermore, the device also includes:

[0083] A conveyor belt control module 6, which controls the running state of the conveyor belt 7;

[0084] A speed measuring module 2, which measures the linear speed of the conveyor belt 7;

[0085] The temperature measuring module 1 measures the ambient temperature.

[0086] This system is a standard lateral force coefficient test system under laboratory conditions. Since the standard value needs to be measured, it is necessary to ensure that the environment in which the system is located is in a standard state. When repeated measurements are made, the environment for each measurement should be the same. This ensures that the measurement results are referenced to each other and the measured standard values ​​are standard.

[0087] Furthermore, the device also includes:

[0088] A control module 8, the control module 8 is connected to the temperature measurement module 1, the speed measurement module 2, the water supply module 4 and the standard lateral force coefficient test system 3;

[0089] The data processing module 9 is connected to the control module 8 and processes the data collected by the control module 8 .

[0090] The control module is connected to all devices to control the operation of the entire system.

[0091] It can be understood that this system is used to measure the standard lateral force coefficient of standard parts, so the surface of the conveyor belt 7 is paved with standard parts, and the standard parts and the transmission belt 7 are detachably fixed together, so that during the operation of the conveyor belt 7, the standard parts also move together, and then the standard parts and the test wheels of the standard lateral force coefficient test system 3 produce relative movement, and then the lateral force coefficient of the standard parts can be measured, and this system needs to measure the standard lateral force coefficients of multiple different standard parts, so the standard parts need to be replaced, and the detachable connection between the standard parts and the conveyor belt 7 makes the standard parts easy to replace, and then the system has strong versatility and can be reused many times. Or optionally, different standard parts are laid at intervals on the same conveyor belt 7, and the lateral force coefficients of different standard parts can be measured during the same operation of the conveyor belt 7.

[0092] In the embodiment of the present application, the conveyor belt control module 6 is connected to the pulley of the conveyor belt 7, and the conveyor belt control module 6 controls the rotation speed of the pulley, and then controls the linear speed of the conveyor belt 7, so that the linear speed of the conveyor belt 7 is uniform, ensuring that the relative speed between the vehicle and the standard part is uniform, and then the measured standard lateral force coefficient is also obtained under the condition of relatively uniform speed. In this way, the measurement result is accurate and will not cause large errors in the result due to different relative speeds.

[0093] It can be understood that the control module 8 is connected to the temperature measurement module 1, the speed measurement module 2, the water supply module 4 and the standard lateral force coefficient test system 3 respectively, and then the control module 8 receives all data such as temperature, speed, water flow, load, etc. The control module 8 transmits all the collected data to the data processing module 9, and the data processing module 9 processes the temperature, speed, water flow, load and other data to obtain the lateral force coefficient data, and compares and eliminates the data with large errors, and averages all the data. The obtained average value is the standard lateral force coefficient.

[0094] Since the influence of linear speed needs to be considered when measuring the standard lateral force coefficient, in a preferred embodiment of the present application, the control module 8 and the conveyor belt control module 6 are electrically connected, and the conveyor belt control module 6 transmits the running linear speed signal of the conveyor belt 7 to the control module 8. The control module 8 converts the linear speed signal into corresponding data and transmits the data to the data processing module 9. The data processing module 9 eliminates the standard lateral force coefficient obtained when the linear speed is uneven, so that the measured standard lateral force coefficient is more accurate, providing an accurate reference for the calibration of the subsequent lateral force coefficient test system.

[0095] It should be understood that although this specification is described according to various implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation method may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0096] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention, and are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention, such as combination, division or repetition of features, should be included in the scope of protection of the present invention.

Claims

1. A lateral force coefficient test system measurement method, characterized in that: The steps include: Standard lateral force coefficient test system (3) measures the standard lateral force coefficients of multiple standard parts with different levels of anti-skid performance; Several standard parts with different levels of skid resistance are laid on the road surface; The lateral force coefficient test system to be calibrated dynamically measures the measured value of the lateral force coefficient of the standard part; Comparison of measured lateral force coefficient with standard lateral force coefficient; According to the measurement error between the measured value of the lateral force coefficient and the standard lateral force coefficient, adjust the lateral force coefficient test system, and repeat the above steps until the measurement error between the measured value of the lateral force coefficient and the standard lateral force coefficient is within the specified error range; The standard lateral force coefficient test system (3) measures the standard lateral force coefficients of a plurality of standard parts with different levels of anti-skid performance, specifically including: The standard part is laid on a conveyor belt (7), and the test wheel of the standard lateral force coefficient test system (3) is placed on the standard part; The load measurement module (5) is placed below the test wheel of the standard lateral force coefficient test system (3), and the counterweight of the test wheel of the standard lateral force coefficient test system (3) is adjusted so that the load measured by the load measurement module (5) is the standard load; Adjusting the ambient temperature, the linear speed of the conveyor belt (7), and the water supply of the water supply module (4) so ​​that the ambient temperature, the relative speed between the test wheel and the conveyor belt (7), and the water supply are consistent with the calibration environment; Determine the standard lateral force coefficient of the standard part using a standard lateral force coefficient test system (3); The test wheel of the standard lateral force coefficient test system (3) is placed above the conveyor belt (7); The load measuring module (5) is located below the conveyor belt (7) at a point where the test wheel contacts the conveyor belt (7), and the load measuring module (5) provides a supporting force for the test wheel and measures the supporting force; The water supply module (4) sprays water onto the contact point between the test wheel of the standard lateral force coefficient test system (3) and the conveyor belt (7), and measures the water flow rate; Repeat the above steps to complete the standard lateral force coefficient measurement of multiple standard parts with different levels of anti-slip performance; The lateral force coefficient test system to be calibrated dynamically measures the lateral force coefficient measurement value of the standard part, including: Adjust the speed of the lateral force coefficient test system to be calibrated to ensure that the speed is uniform; The test wheel of the lateral force coefficient test system to be calibrated passes the standard part in a straight line at a uniform speed to obtain the measured value of the lateral force coefficient; Repeat the above steps to obtain multiple groups of lateral force coefficient measurement values, and take the average value, which is the lateral force coefficient measurement value of the standard part; The laying length of the standard part is not less than twice the circumference of the test wheel of the standard lateral force coefficient test system (3).

2. The measuring method according to claim 1, characterized in that: When measuring the standard lateral force coefficient of the standard part, the standard lateral force coefficient measurement of the same standard part is repeated five times. Among the five sets of data obtained, the maximum value and the minimum value are removed, and the average value of the remaining three sets of data is taken, which is the standard lateral force coefficient.

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