A method for early warning of cargo displacement and overturning of a fast-loading device

Abstract

The present invention discloses a method for early warning of cargo displacement and overturning of a fast-loading device. In order to overcome the problem that the existing technology cannot solve the threat of cargo overturning caused by the slope when loading and unloading cargo; the present invention includes the following steps: S1: Collecting the center of gravity mapping of the cargo on the bottom pallet when on a plane; S2: Evaluating the estimated transfer amount of the center of gravity mapping according to the transportation speed of the fast-loading device, the slope angle and the weight distribution of the cargo; S3: After the cargo enters the slope for transportation, collecting the center of gravity mapping on the slope; setting the initial sampling frequency according to the difference between the estimated transfer amount and the actual transfer amount of the center of gravity mapping; S4: Collecting the center of gravity mapping position at the initial sampling frequency, and adjusting the sampling frequency and performing an overturning early warning according to the change rate of the center of gravity mapping position and the set safety threshold. By calculating the change rate of the center of gravity mapping, it is possible to estimate whether the cargo will be displaced or overturned during the slope transportation process, and to give an early warning to ensure the safety of the cargo when it is transported on the slope.

Description

Technical Field

[0001] The invention relates to the field of cargo displacement and overturning warning, and in particular to a cargo displacement and overturning warning method for a fast-loading device. Background Art

[0002] With the improvement of the automation level of logistics systems, the handling of goods in many scenarios has gradually been replaced by automated equipment instead of manual labor, reducing the labor intensity of people. As a part of the cargo handling, the fast loading device transports the goods to the next link through various conveying structures, such as rollers.

[0003] The quick-loading device is generally installed at the bottom of the carriage of the transport vehicle. During the cargo loading and unloading process, a slope needs to be built between the carriage and the ground through the quick-loading device to load the cargo into the carriage or unload it to the ground. This process may cause the upper layer of cargo to shift or overturn for double-layer loading and unloading, and the safety of the transported products cannot be guaranteed; it may also cause the cargo to move inside the box and collide with the box containing the cargo.

[0004] At present, there are fast-loading devices designed to prevent cargo from overturning. For example, a "flat conveyor chain belt safety control device" disclosed in Chinese patent documents, with announcement number CN211970824U, is provided with front drive wheels, rear drive wheels and chain belts on the two side frames of the base, and the front drive wheels are driven to rotate by a reduction motor to pull the chain belt to carry the vehicle to move; the safety control device is provided with infrared detectors on the top surfaces of the two side frames of the base to detect the deflection of the wheels, thereby controlling the operation and stop of the chain belt. However, this solution still cannot solve the overturning threat caused by the slope angle when loading and unloading goods. Summary of the invention

[0005] The present invention mainly solves the problem that the existing technology cannot solve the threat of cargo overturning caused by slopes when loading and unloading cargo; it provides a cargo displacement and overturning warning method for a fast-loading device, which estimates whether the cargo will be displaced or overturned during slope transportation by calculating the mapping change position of the center of gravity, and gives an early warning to ensure the safety of cargo when transported on a slope.

[0006] The above technical problems of the present invention are mainly solved by the following technical solutions:

[0007] A method for early warning of cargo displacement and overturning of a fast-loading device comprises the following steps:

[0008] S1: The center of gravity mapping of the cargo on the bottom pallet when collected on a plane;

[0009] S2: Evaluate the estimated transfer amount of the center of gravity mapping based on the transportation speed of the fast-loading device, the slope angle and the weight distribution of the cargo;

[0010] S3: After the goods enter the ramp for transportation, the center of gravity map on the ramp is collected; the initial sampling frequency is set according to the difference between the estimated transfer amount and the actual transfer amount of the center of gravity map;

[0011] S4: Collect the center of gravity mapping position at the initial sampling frequency, and adjust the sampling frequency and issue a capsize warning based on the comparison of the change rate of the center of gravity mapping position with the set safety threshold.

[0012] By calculating the mapping change rate of the center of gravity, it is possible to estimate whether the cargo will be displaced or overturned during the slope transportation process, and to provide early warning to ensure the safety of the cargo when transported on the slope. Adjusting the sampling frequency according to different position change rates can not only ensure the collection of enough key data for estimating the overturning of the cargo and ensuring the accuracy of the results, but also reduce the collection of useless data, save energy and improve efficiency.

[0013] Preferably, a matrix pressure sensor is provided on the pallet, and the center of gravity mapping of the goods to the pallet plane is calculated by collecting pressure values ​​at various positions.

[0014] The weight of the three-dimensional cargo is mapped onto the pallet to form a plane with a regular shape and uniform or uneven weight distribution. The center of gravity mapping of the cargo to the pallet is calculated based on the center of gravity coordinate formula. The vertical offset of the center of gravity has little effect on the overturning of the cargo, reducing the vertical amount of the center of gravity, which is convenient for the subsequent estimation of the center of gravity offset.

[0015] Preferably, the center of gravity mapping coordinates are:

[0016]

[0017]

[0018] Among them, (x c ,y c ) is the barycentric mapping coordinate;

[0019] x i is the horizontal coordinate of the pallet plane coordinate system;

[0020] w i The horizontal axis x i The corresponding weight on

[0021] y i is the ordinate of the pallet plane coordinate system;

[0022] w j The vertical coordinate y j The corresponding weight on

[0023] W is the resultant force of all unit weights.

[0024] The center of gravity mapping of the cargo to the pallet is calculated according to the center of gravity coordinate formula.

[0025] Preferably, the calculation process of the estimated transfer amount is:

[0026]

[0027] Among them, |T r |Estimated modulus of transfer volume;

[0028] θ is the slope angle;

[0029] V t is the transport speed of the fast-loading device;

[0030] ω v is the set speed weighting coefficient;

[0031] V S The maximum transport speed is set;

[0032] W t is the weight of the cargo;

[0033] ω W The weighting factor for the set cargo weight;

[0034] W S The maximum weight of the cargo.

[0035] The transfer amount of the center of gravity mapping is calculated based on the weight, transportation speed and slope angle of the current cargo according to historical data, and its transfer range is estimated.

[0036] Preferably, the process of setting the initial sampling frequency is:

[0037] Using the transfer quantity difference and the cargo attributes as the row and column dimensions, an initial sampling frequency query table is established;

[0038] Calculate the transfer volume difference, and obtain the corresponding initial sampling frequency f0 based on the calculated transfer volume difference and the corresponding cargo attributes.

[0039] Different cargo properties pose different threats to capsizing and require different sampling frequencies.

[0040] As a preferred method, the sampling frequency adjustment process is:

[0041]

[0042] ΔT rk =|(x k -x k-1 ,y k -y k-1 )|

[0043] Among them, f k is the adjusted sampling frequency;

[0044] f k-1 is the sampling frequency of the previous moment;

[0045] [·] is the rounding operation;

[0046] V s is the minimum unit change rate set;

[0047] f s is the set adjustment frequency;

[0048] ΔT rk is the position change of the center of gravity map;

[0049] |·| is the module length calculation;

[0050] (x k ,y k ) is the center of gravity mapping coordinate at the current moment;

[0051] (x k-1 ,y k-1 ) is the coordinate of the center of gravity mapping at the previous moment.

[0052] Adjusting the sampling frequency according to different rates of position change can not only ensure that enough key data is collected to predict the overturning of cargo and ensure the accuracy of the results, but also reduce the collection of useless data, save energy and improve efficiency.

[0053] Preferably, when the rate of change of the center of gravity mapping position is greater than or equal to a set safety threshold, an alarm is issued to relevant personnel;

[0054] When the rate of change of the center of gravity mapping position is less than the set safety threshold, data collection is performed according to the adjusted sampling frequency until the cargo is transported to the plane.

[0055] As a preference, it also includes:

[0056] S5: Use an ultrasonic probe to scan the positions of the cargo before entering the ramp and after exiting the ramp; compare the relative position offset between the double-layer cargo; if the offset is greater than the set offset threshold, issue an alarm; otherwise, end.

[0057] Based on the result feedback, adjust the set safety threshold and optimize the algorithm.

[0058] The beneficial effects of the present invention are:

[0059] 1. By calculating the mapping change rate of the center of gravity, it is estimated whether the goods will be displaced or overturned during slope transportation, and early warning is given to ensure the safety of goods when transported on the slope.

[0060] 2. Adjusting the sampling frequency according to different rates of position change can not only ensure the collection of sufficient key data for estimating the overturning of goods and ensuring the accuracy of the results, but also reduce the collection of useless data, save energy and improve efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 The present invention is a flow chart of a method for early warning of cargo displacement and overturning of a fast-loading device. DETAILED DESCRIPTION

[0062] The technical solution of the present invention is further specifically described below through embodiments and in conjunction with the accompanying drawings.

[0063] Example:

[0064] A method for early warning of cargo displacement and overturning of a fast-loading device in this embodiment is as follows: Figure 1 As shown, the following steps are included:

[0065] S1: Collect the center of gravity mapping of the goods on the bottom pallet when on a flat surface.

[0066] A matrix pressure sensor is provided on the pallet, and the center of gravity mapping of the cargo to the pallet plane is calculated by collecting the pressure values ​​at each position. In this embodiment, pressure sensors are distributed on the surface of the pallet, a plane coordinate system is established, and the mapping coordinates of the center of gravity are calculated according to the center of gravity calculation formula.

[0067] The barycentric mapping coordinates are:

[0068]

[0069]

[0070] Among them, (x c ,y c ) is the barycentric mapping coordinate;

[0071] x i is the horizontal coordinate of the pallet plane coordinate system;

[0072] w i The horizontal axis x i The corresponding weight on

[0073] y j is the ordinate of the pallet plane coordinate system;

[0074] w j The vertical coordinate y j The corresponding weight on

[0075] W is the resultant force of all unit weights.

[0076] The weight of the three-dimensional cargo is mapped onto the pallet to form a plane with a regular shape and uniform or uneven weight distribution. The center of gravity mapping of the cargo to the pallet is calculated based on the center of gravity coordinate formula. The vertical offset of the center of gravity has little effect on the overturning of the cargo, reducing the vertical amount of the center of gravity, which is convenient for the subsequent estimation of the center of gravity offset.

[0077] S2: Evaluate the estimated transfer amount of the center of gravity map based on the transport speed of the fast-loading device, the slope angle and the cargo weight distribution.

[0078] The calculation process of the estimated transfer amount is:

[0079]

[0080] Among them, |T r |Estimated modulus of transfer volume;

[0081] θ is the slope angle;

[0082] V t is the transport speed of the fast-loading device;

[0083] ω v is the set speed weighting coefficient;

[0084] V S The maximum transport speed is set;

[0085] W t is the weight of the cargo;

[0086] ω W The weighting factor for the set cargo weight;

[0087] W S The maximum weight of the cargo.

[0088] The set value is derived comprehensively based on historical data. Corresponding to different slope angles, the speed and weight thresholds of overturning are set to estimate the center of gravity transfer in the current transportation situation, so as to determine the possibility of overturning.

[0089] S3: After the goods enter the ramp for transportation, the center of gravity map on the ramp is collected; the initial sampling frequency is set according to the difference between the estimated transfer amount and the actual transfer amount of the center of gravity map.

[0090] In this embodiment, a pair of infrared lasers are set at the bottom of the car door. When the pallet is still on the plane, the infrared lasers are blocked. When the pallet just enters the ramp, the infrared lasers receive the reflected signal and determine that the goods have entered the ramp at this time.

[0091] The data of the matrix pressure sensor at this time is collected, and the center of gravity is mapped on the pallet plane according to the center of gravity formula.

[0092] The process of setting the initial sampling frequency is:

[0093] Using the transfer quantity difference and the cargo attributes as the row and column dimensions, an initial sampling frequency query table is established;

[0094] Calculate the transfer volume difference, and obtain the corresponding initial sampling frequency f0 based on the calculated transfer volume difference and the corresponding cargo attributes.

[0095] In this embodiment, the cargo attributes include fragile cargo, inflammable and explosive cargo, corrosive cargo, and common cargo, etc., and an initial sampling frequency query table as shown in Table 1 is established.

[0096] Table 1. Initial sampling frequency lookup table

[0097] Fragile Inflammable and explosive items Corrosive cargoes General goods 0.10rn 8 10 8 5 0.15m 12 15 12 10 0.20m 16 20 16 10 0.25m 20 25 20 15 0.30m 24 30 24 15

[0098] Different cargo properties pose different threats to capsizing and require different sampling frequencies.

[0099] S4: Collect the center of gravity mapping position at the initial sampling frequency, and adjust the sampling frequency and issue a capsize warning based on the comparison of the change rate of the center of gravity mapping position with the set safety threshold.

[0100] The sampling frequency adjustment process is:

[0101]

[0102] ΔT rk =|(x k -x k-1 ,y k -y k-1 )|

[0103] Among them, f k is the adjusted sampling frequency;

[0104] f k-1 is the sampling frequency of the previous moment;

[0105] [·] is the rounding operation;

[0106] V s is the minimum unit change rate set;

[0107] f s is the set adjustment frequency;

[0108] ΔT rk is the position change of the center of gravity map;

[0109] |·| is the module length calculation;

[0110] (x k ,y k) is the center of gravity mapping coordinate at the current moment;

[0111] (x k-1 ,y k-1 ) is the coordinate of the center of gravity mapping at the previous moment.

[0112] Adjusting the sampling frequency according to different rates of position change can not only ensure that enough key data is collected to predict the overturning of cargo and ensure the accuracy of the results, but also reduce the collection of useless data, save energy and improve efficiency.

[0113] When the rate of change of the center of gravity mapping position is greater than or equal to the set safety threshold, an alarm is issued to relevant personnel.

[0114] When the rate of change of the center of gravity mapping position is less than the set safety threshold, data collection is performed according to the adjusted sampling frequency until the cargo is transported to the plane.

[0115] S5: Use an ultrasonic probe to scan the positions of the cargo before entering the ramp and after exiting the ramp; compare the relative position offset between the double-layer cargo; if the offset is greater than the set offset threshold, issue an alarm; otherwise, end.

[0116] Based on the result feedback, adjust the set safety threshold and optimize the algorithm.

[0117] By calculating the mapping change rate of the center of gravity, it is possible to estimate whether the cargo will be displaced or overturned during the slope transportation process, and to provide early warning to ensure the safety of the cargo when transported on the slope. Adjusting the sampling frequency according to different position change rates can not only ensure the collection of enough key data for estimating the overturning of the cargo and ensuring the accuracy of the results, but also reduce the collection of useless data, save energy and improve efficiency.

[0118] It should be understood that the embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope limited by the appended claims of the application.

Claims

1. A method for early warning of cargo displacement and overturning of a fast-loading device, characterized in that: The following steps are involved: S1: The center of gravity mapping of the cargo on the bottom pallet when collected on a plane; S2: evaluating the estimated transfer amount of the center of gravity mapping according to the transport speed of the fast-loading device, the slope angle and the cargo weight distribution, specifically comprising first multiplying the set speed weighting coefficient by the ratio of the transport speed of the fast-loading device to the set maximum transport speed, then adding the set cargo weight weighting coefficient multiplied by the ratio of the cargo weight to the set maximum cargo weight, and finally multiplying by the cosine value of the slope angle; S3: After the goods enter the ramp for transportation, the center of gravity map on the ramp is collected; the initial sampling frequency is set according to the difference between the estimated transfer amount and the actual transfer amount of the center of gravity map; S4: Collect the center of gravity mapping position at the initial sampling frequency, and adjust the sampling frequency and issue a capsize warning based on the comparison of the change rate of the center of gravity mapping position with the set safety threshold.

2. A method for early warning of cargo displacement and overturning of a fast-loading device according to claim 1, characterized in that: The pallet is provided with a matrix pressure sensor, which collects pressure values ​​at various positions to calculate the center of gravity mapping of the goods to the pallet plane.

3. A method for early warning of cargo displacement and overturning of a fast-loading device according to claim 1 or 2, characterized in that: The centroid mapping coordinates are: Among them, (x c ,y c ) is the barycentric mapping coordinate; x i is the horizontal coordinate of the pallet plane coordinate system; w i The horizontal axis x i The corresponding weight on y j is the ordinate of the pallet plane coordinate system; w j The vertical coordinate y j The corresponding weight on W is the resultant force of all unit weights.

4. A method for early warning of cargo displacement and overturning of a fast-loading device according to claim 1, characterized in that: The calculation process of the estimated transfer amount is: Among them, |T r |Estimated modulus of transfer volume; θ is the slope angle; V t is the transport speed of the fast-loading device; ω v is the set speed weighting coefficient; V S The maximum transport speed is set; W t is the weight of the cargo; ω W The weighting factor for the set cargo weight; W S The maximum weight of the cargo.

5. A method for early warning of cargo displacement and overturning of a fast-loading device according to claim 1 or 4, characterized in that: The setting process of the initial sampling frequency is: Using the transfer quantity difference and the cargo attributes as the row and column dimensions, an initial sampling frequency query table is established; Calculate the transfer volume difference, and obtain the corresponding initial sampling frequency f0 based on the calculated transfer volume difference and the corresponding cargo attributes.

6. A method for early warning of cargo displacement and overturning of a fast-loading device according to claim 5, characterized in that: The sampling frequency adjustment process is: ΔT rk =|(x k -x k-1 ,y k -y k-1 )| Among them, f k is the adjusted sampling frequency; f k-1 is the sampling frequency of the previous moment; [·] is the rounding operation; V s is the minimum unit change rate set; f s is the set adjustment frequency; ΔT rk is the position change of the center of gravity map; |·| is the modulus length calculation; (x k ,y k ) is the center of gravity mapping coordinate at the current moment; (x k-1 ,y k-1 ) is the coordinate of the center of gravity mapping at the previous moment.

7. A method for early warning of cargo displacement and overturning of a fast-loading device according to claim 1 or 6, characterized in that: When the rate of change of the center of gravity mapping position is greater than or equal to the set safety threshold, an alarm is issued to relevant personnel; When the rate of change of the center of gravity mapping position is less than the set safety threshold, data collection is performed according to the adjusted sampling frequency until the cargo is transported to the plane.

8. The method for early warning of cargo displacement and overturning of a fast-loading device according to claim 1, characterized in that: Also includes: S5: Use an ultrasonic probe to scan the positions of the cargo before entering the ramp and after exiting the ramp; compare the relative position offset between the double-layer cargo; if the offset is greater than the set offset threshold, issue an alarm; otherwise, end.

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