TWI741366B - System and method for estimating transportation risk - Google Patents

Abstract

A method for estimating transporation risk is adapted to an object transported by a vehicle. The method comprises disposing a sensor on a floor board of the vehicle to collect a vibration signal, with the floor board being configured to load the object, a computing device performs a time-domain processing task according to the vibration signal to output a first data, performs a frequency-domain processing task according to the first data to output a second data, performing a risk estimation procedure to output a risk level according to the second data and a tesingt data, wherein the second data comprises a real vibrating intensity and a real vibrating time and the testing data comprises a testing vibrating intensity and a testing vibrating time.

Description

Transportation risk assessment system and method

The invention relates to a transportation risk assessment system and a method thereof.

In the process where the supplier provides the server to its customer, the assembled complete cabinet will be transported from the production site to the customer's location. In the process of transporting the entire cabinet by the vehicle, the high-speed vehicle generates continuous vibration due to the uneven road surface. During transportation, vibration cannot be avoided and persists. Vibration of certain frequencies may cause the sensitive components in the product to resonate. Although the stress generated by a single vibration will not cause damage to the component immediately, the long-term continuous loop stress will cause fatigue damage to the component structure, which will affect the function of the product. Or damage the product. The vibration intensity, occurrence time, and number of occurrences during transportation cannot be predicted and are random. Therefore, probability and statistics methods must be used to study the characteristics of vibration signals during transportation.

Generally speaking, the data collection of vibration signals is based on a specific transportation route, and the collected data can only represent the average vibration level of the route. The random vibration reliability test currently used by most companies refers to the standards set by the American Society for Testing and Materials (ASTM) or the International Safe Transit Association (ISTA). However, these two standards are based on the specified load capacity, and the truck with the specified suspension system is used as the basic situation to collect data on the expressway at the specified speed. The actual freight situation is often very different from it, so the above two standards are not accurate. Evaluate the vibration risk of actual transportation under various conditions.

In view of this, the present invention proposes a transportation risk assessment system and method, which collect and process random vibration data of actual transportation to prepare random vibration acceleration power density spectrum to evaluate the vibration risk of products during actual transportation.

According to an embodiment of the present invention, a transportation risk assessment method is applicable to objects transported by vehicles. The method includes: arranging a sensor on the floor of the vehicle, the floor is used to carry objects; the sensor collects the vehicle transportation process In the vibration signal; the computing device executes the time domain processing procedure according to the vibration signal to output the first data; the computing device executes the frequency domain processing procedure according to the first data to output the second data; and the computing device executes the risk based on the second data and the test data The evaluation process outputs the risk level, where the second data includes actual vibration intensity and actual vibration time, and the test data includes test vibration intensity and test vibration time.

According to an embodiment of the present invention, a transportation risk assessment system is suitable for objects transported by vehicles. The system includes a sensor, a storage device, and a computing device. The sensor is arranged on the floor of the vehicle. The sensor is used to collect vibration signals during vehicle transportation. The storage device is used to store the test data. The test data includes test vibration time and test vibration intensity. The computing device is connected to the storage device in communication. The arithmetic device is used to execute time domain processing procedures, frequency domain processing procedures and risk assessment procedures. The time domain processing program outputs the first data according to the vibration signal. The frequency domain processing program outputs the second data according to the first data. The second data includes actual vibration intensity and actual vibration time. The risk assessment procedure outputs the risk level based on the second data and the test data.

With the above structure, the transportation risk assessment system and method disclosed in the present invention can compare the actual collected transportation vibration data with the laboratory test vibration data to accurately evaluate the risk level during actual transportation, and When the evaluation results are applied to the packaging of the entire cabinet, a design to reduce vibration is added to ensure the quality of the product after it is transported to the destination.

The above description of the disclosure and the following description of the implementation manners are used to demonstrate and explain the spirit and principle of the present invention, and to provide a further explanation of the patent application scope of the present invention.

The detailed features and advantages of the present invention will be described in detail in the following embodiments. The content is sufficient to enable anyone familiar with the relevant art to understand the technical content of the present invention and implement it accordingly, and according to the content disclosed in this specification, the scope of patent application and the drawings. Anyone who is familiar with relevant skills can easily understand the purpose and advantages of the present invention. The following examples further illustrate the viewpoints of the present invention in detail, but do not limit the scope of the present invention by any viewpoint.

Please refer to FIG. 1, which is a block diagram of a transportation risk assessment system according to an embodiment of the present invention. As shown in FIG. 1, the system includes a sensor 10, a computing device 30 and a storage device 50.

The sensor 10 performs sensing to generate sensing data. The computing device 30 is used to obtain the sensing data of the sensor 10. For example, the way for the computing device 30 to obtain the sensing data from the sensor 10 may be: electrically connecting the sensor 10 to the computing device 30 to transmit the sensing data, and storing the sensing data inside the sensor 10 The memory card is electrically connected to the computing device 30 to transmit sensing data, or the computing device 30 downloads the sensing data from the sensor 10 to the cloud through the network, and the present invention obtains the sensing data of the sensor 10 from the computing device 30 The method is not limited. The storage device 50 stores test data, and the storage device 50 is communicatively connected to the computing device 30 to transmit the test data.

Please refer to FIG. 2, which is a schematic diagram showing the configuration of the sensor 10 to collect sensing data. The transportation risk assessment system of an embodiment of the present invention is suitable for evaluating the risk level of an object 70 that is actually transported by a vehicle 90. The object 70 is, for example, a complete cabinet, a server, or goods susceptible to vibration. The vehicle 90 has a bottom plate 92 for carrying objects 70.

Please refer to FIG. 3, which shows a flowchart of a transportation risk assessment method according to an embodiment of the present invention. The transportation risk assessment system of an embodiment of the present invention operates according to the process shown in FIG. 3.

Please refer to step S10 in FIG. 2 and FIG. 3 to install the sensor 10 on the floor 92 of the vehicle 90. The sensor 10 is used to collect the vibration signal of the vehicle 90 during transportation. The sensor 10 has a three-axis accelerometer and a built-in power supply, which can record acceleration signals during transportation, such as the SAVER 3X90 environmental recorder manufactured by Lansmont, USA. In practice, a base 12 with a powerful magnet can be used to attach the sensor 10 to the floor of the truck compartment, as shown in FIG. 2. However, the setting method of the sensor 10 is not limited to this. It should also be noted that the sensor 10, the object 70 of the base 12, the vehicle 90 and the bottom plate 92 shown in FIG. 2 are not drawn according to actual scale, but are only used as an example to illustrate the relative positions of these elements.

Please refer to step S12 to collect the vibration signal of the vehicle 90 during transportation by the sensor 10. In detail, the sensor 10 is activated at the beginning of the transportation to collect data, the sensor is turned off after the goods arrive, and the vibration signal collected during the sensing period is exported to the computing device 30 (equivalent to the computing device 30 being used by the sensor 10 Obtain the vibration signal). The vibration signal is, for example, a three-axis acceleration signal. The arithmetic device 30 can execute time-domain processing procedures, frequency-domain processing procedures, and risk assessment procedures according to the vibration signal. The time-domain processing procedure outputs the first data based on the vibration signal, corresponding to step S20 in FIG. 3; the frequency-domain processing procedure is based on The first data outputs the second data, which corresponds to step S22 in FIG. 3, and the risk assessment procedure outputs the risk level based on the second data and the test data, which corresponds to step S30 in FIG. 3.

Please refer to step S20, the computing device 30 executes a time-domain processing procedure according to the vibration signal to output the first data. Specifically, the computing device 30 eliminates the noise in the vibration signal. In practice, due to voltage or environmental factors, the vibration signal tends to drift upward gradually. Therefore, the computing device 30 eliminates the linear trend term and the quadratic trend term in the original signal to output a vibration signal showing a horizontal trend, which is referred to as the third data here. Then, the arithmetic device 30 calculates an average value of the third data and determines whether the average value reaches an average threshold value, if "Yes", the average value threshold value is eliminated from the third data and the eliminated data is used as the fourth data, if "No" "The third data is used as the fourth data. Then, the computing device 30 filters the parking data from the fourth data according to a peak threshold (for example, 0.1 g) to use as the fifth data. The parking data is the data measured when the vehicle stops during transportation, and because these data do not help evaluate transportation risks, they need to be filtered out. The arithmetic device 30 then performs a low-pass filtering process according to a cutoff frequency and the fifth data to output the first data, so that the sampling frequency range of the first data (for example, 0~200 Hz) corresponds to the sampling frequency range of the test data.

Please refer to step S22, the computing device 30 performs a frequency domain processing procedure on the first data to output the second data. Specifically, the computing device 30 extracts multiple frequency points and the vibration amplitude at each frequency point from the first data. In practice, the computing device 30 performs Fast Fourier Transform (FFT) according to the first data that has undergone the time-domain processing procedure and a plurality of preset parameters to output the second data. The second data includes actual vibration intensity and actual vibration time. The preset parameters include FFT parameters, sampling frequency and maximum analysis frequency.

Please refer to step S30. The computing device 30 executes a risk assessment procedure based on the second data and the test data to output a risk level. The second data includes actual vibration intensity and actual vibration time, and the test data includes test vibration intensity and test vibration time. In detail, the test data generated after the vibration test in the laboratory is stored in the storage device 50 as the test data. Compared with actual transportation, the vibration test conducted in the laboratory uses a larger vibration intensity and a relatively short test time. The present invention is calculated based on the linear fatigue cumulative damage theory (Palmgren-Miner rule), and the following relationship is established between the vibration intensity and the vibration time:

（第1式）

(Form 1)

Where t _t represents the test vibration time, a _t represents the root mean square value of the test vibration intensity (Grms), a _a represents the root mean square value of the actual vibration intensity (Grms), t _a represents the actual vibration time, and k generally takes 2.

Please refer to FIG. 4, which illustrates a risk assessment procedure of an embodiment of the present invention.

Please refer to step S32, the computing device 30 adjusts the actual vibration intensity of the second data according to the test vibration intensity of the test data, and adjusts the actual vibration time of the second data according to the test vibration time of the test data.

Please refer to step S34, the computing device 30 converts the actual vibration time of the second data to another vibration time according to the adjusted actual vibration intensity, and converts the actual vibration intensity of the second data to another vibration intensity according to the adjusted actual vibration time .

Please refer to step S36, the computing device 30 compares the test vibration time and another vibration time and compares the test vibration intensity and another vibration intensity to output the risk level.

Regarding the risk level determination in step S36, in detail, if the comparison of vibration intensity and vibration time is considered at the same time, there are four situations as follows:

Condition 1: The test vibration intensity is greater than the other vibration intensity, and the test vibration time is greater than the other vibration time.

Condition 2: The test vibration intensity is greater than the other vibration intensity, and the test vibration time is less than or equal to the other vibration time.

Condition 3: The test vibration intensity is less than or equal to another vibration intensity, and the test vibration time is longer than the other vibration time.

Condition 4: The test vibration intensity is less than or equal to another vibration intensity, and the test vibration time is less than or equal to another vibration time.

If the computing device 30 obtains the situation 1 through the comparison, it can be determined that the risk level is low. If the computing device 30 obtains the situation 4 through the comparison, it can be determined that the risk level is high. If the computing device 30 obtains status 2 or 3 through the comparison, it can selectively focus on the vibration time or the vibration intensity or choose not to focus on either according to the actual situation. For example, if the vibration time is selected to give priority to consideration, for situation 2, the computing device 30 determines that the risk level is “medium-high”, and for situation 3, the computing device 30 determines that the risk level is “medium-low”. If it is chosen to give priority to the vibration intensity, for situation 2, the computing device 30 determines that the risk level is “medium-low”, and for situation 3, the computing device 30 determines that the risk level is “medium-high”. If you choose not to emphasize either, the computing device 30 determines that the risk level is "medium" for both situation 2 and situation 3.

Please refer to FIG. 5, which illustrates a risk assessment program of another embodiment of the present invention. The risk assessment program of this embodiment is equivalent to a simplified version of the risk assessment program of the previous embodiment.

倍。Please refer to step S42, the computing device 30 adjusts the actual vibration intensity of the second data according to the test vibration intensity of the test data. For example, vibration test data of time t _t hypothesis testing is 2 hours, the test data of the vibration intensity test is a _t 1.146 g; and a second data assuming the actual vibration strength 0.239 g of a _a, t _a time of the actual vibration 24 hours. In step S42, a second metric based on actual test data of a _t test vibration intensity adjustment required a _a magnification of about

Times.

Please refer to step S44, the computing device 30 converts the actual vibration time of the second data into another vibration time according to the adjusted actual vibration intensity. Following the previous example, the computing device 30 substituting the above-mentioned value into the first formula can convert another vibration time of 1.04 hours.

Please refer to step S46, the computing device 30 compares the test vibration time with another vibration time to output a risk level. The risk level can be divided into two levels, high and low, for example. Following the previous example, since 2 hours is greater than 1.04 hours, it can be judged that the test intensity in the laboratory is greater than the vibration intensity in actual transportation, so the risk level is judged to be "low". Otherwise, the risk level is judged to be "high".

It should be noted that the risk assessment procedure in Fig. 5 is only a simplified implementation of the risk assessment procedure in Fig. 4. Those skilled in the art to which the present invention pertains can obtain another implementation (compare the test vibration intensity and another vibration intensity to output the risk level by the computing device 30) based on FIGS. 4 and 5, which will not be repeated here.

In summary, the transportation risk assessment system and method disclosed in the present invention can accurately evaluate the risk level during actual transportation through interactive comparison between the actually collected transportation vibration data and laboratory test vibration data, and When the evaluation results are applied to the packaging of the entire cabinet, a design to reduce vibration is added to ensure the quality of the product after it is transported to the destination.

Although the present invention is disclosed in the foregoing embodiments, it is not intended to limit the present invention. All changes and modifications made without departing from the spirit and scope of the present invention fall within the scope of the patent protection of the present invention. For the scope of protection defined by the present invention, please refer to the attached scope of patent application.

10: Sensor 12: Base 30: storage device 50: computing device 70: Object 90: Vehicle 92: bottom plate S10~S30: steps

FIG. 1 is a block diagram of a transportation risk assessment system according to an embodiment of the present invention. Figure 2 is a schematic diagram showing the setup of the sensor to collect sensing data. FIG. 3 is a flow chart of a transportation risk assessment method according to an embodiment of the present invention. FIG. 4 is a flowchart of a risk assessment program according to an embodiment of the present invention. FIG. 5 is a flowchart of a risk assessment program according to another embodiment of the present invention.

S10~S30: steps

Claims (8)

A transportation risk assessment method is suitable for transporting an object by a vehicle. The method includes: arranging a sensor on a floor of the vehicle, wherein the floor is used to carry the object; and the sensor is used to collect the object. A vibration signal during vehicle transportation; a computing device executes a time domain processing procedure based on the vibration signal to output a first data; the computing device executes a frequency domain processing procedure based on the first data to output a second data And using the computing device to execute a risk assessment procedure based on the second data and a test data to output a risk level, wherein the second data includes an actual vibration intensity and an actual vibration time, and the test data includes a test vibration intensity And a test vibration time, and the time-domain processing procedure further includes: using the computing device to eliminate linear trend terms and quadratic trend terms based on the vibration signal to output a third data; using the computing device to output a third data based on an average threshold and the first Three data execute a mean value elimination process to output a fourth data; use the computing device to execute a parking data filtering process based on a peak threshold and the fourth data to output a fifth data; and use the computing device to output a cutoff frequency And the fifth data performs a low-pass filtering process to output the first data. The transportation risk assessment method according to claim 1, wherein executing the risk assessment procedure by the computing device according to the second data and the test data further includes: adjusting the second data by the computing device according to the test vibration intensity of the test data The actual vibration intensity of the second data; the actual vibration time of the second data is adjusted by the computing device according to the test vibration time of the test data; the actual vibration time of the second data is converted by the computing device according to the adjusted actual vibration intensity The actual vibration time is another vibration time; the calculation device converts the actual vibration intensity of the second data into another vibration intensity according to the adjusted actual vibration time; and the calculation device compares the test vibration time and The other vibration time is compared with the test vibration intensity and the other vibration intensity to output the risk level. The transportation risk assessment method according to claim 1, wherein the vibration signal is a three-axis acceleration signal. The transportation risk assessment method of claim 1, wherein the frequency domain processing program further includes: using the computing device to perform a fast Fourier calculation based on the first data, a fast Fourier parameter, a sampling frequency, and a maximum analysis frequency to Output the second data. A transportation risk assessment system is suitable for transporting an object by a vehicle. The system includes: a sensor arranged on a floor of the vehicle; the sensor is used to collect a vibration signal during the transportation of the vehicle ； A storage device for storing a test data, the test data including a test vibration intensity and a test vibration time; and an arithmetic device, communicatively connected to the storage device, the arithmetic device for obtaining the vibration signal from the sensor , The arithmetic device is used to execute a time-domain processing procedure, a frequency-domain processing procedure and a risk assessment procedure, wherein the time-domain processing procedure is used to output a first data according to the vibration signal; the frequency-domain processing procedure is used according to the The first data outputs a second data, the second data includes an actual vibration intensity and an actual vibration time; the risk assessment procedure is used to output a risk level based on the second data and the test data, wherein the time domain processing procedure The arithmetic device eliminates the linear trend term and the quadratic trend term according to the vibration signal to output a third data, executes an average elimination procedure according to an average threshold and the third data to output a fourth data, and outputs a fourth data according to a peak threshold and The fourth data executes a parking data filtering process to output a fifth data, and executes a low-pass filtering process according to a cutoff frequency and the fifth data to output the first data. The transportation risk assessment system according to claim 5, wherein the risk assessment procedure is: the computing device converts the actual vibration of the second data according to the test vibration intensity of the test data and the actual vibration intensity of the second data Time is another vibration time; the computing device converts the actual vibration intensity of the second data into another vibration intensity based on the test vibration time of the test data and the actual vibration time of the second data; and the computing device ratio The test vibration time and the another vibration time are compared with the test vibration intensity and the another vibration intensity to output the risk level. The transportation risk assessment system according to claim 5, wherein the vibration signal is a three-axis acceleration signal. The transportation risk assessment system of claim 5, wherein the frequency domain processing program is that the arithmetic device executes a fast Fourier calculation based on the first data, a fast Fourier parameter, a sampling frequency, and a maximum analysis frequency to output the first data 2. Information.

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