Four-way vehicle positioning deviation correction algorithm

Abstract

The invention provides a four-way vehicle positioning correction algorithm. The algorithm comprises the following steps: Z1, initial recording: initially setting a real-time coding value S1 and a theoretical coding value L1; z2, recording a successful value: counting holes of the hole position coordinates of the goods shelf, storing a theoretical code value of successful hole counting into a theoretical value temporary storage L2, and storing an actual code value of successful hole counting into an actual value temporary storage S2; z3, calculating a variable quantity: calculating a coded value variable quantity S3 according to the actual value temporary storage S2 and the actual coded value S1; and Z4, calculating a virtual correction value. The invention further provides a computer readable storage medium. According to the invention, accumulative errors caused by insufficient mechanical performance and precision can be effectively solved, and the low-cost positioning precision of a common incremental encoder with a plurality of holes is ensured; the method is simple, reliable, low in cost, accurate in positioning, high in fault tolerance and insensitive to external influence, and can be widely applied to shuttle trolleys.

Description

Technical Field

[0001] The invention relates to a four-way vehicle positioning and deviation correction algorithm, belonging to the technical field of logistics control. Background Art

[0002] The incremental encoder is coaxial with the driven wheel, so the encoder reading is the actual number of turns of the wheel. However, during driving, due to different load sizes, the wheel deformation will be different, so the code value read by the trolley through each hole is different, and there is a cumulative error. Therefore, inaccurate positioning will occur during long-distance operation. Similarly, excessive mechanical clearance or improper assembly may cause this situation.

[0003] In practice, assuming that there are 100 cargo positions in a single row or column, it will be set as 100 holes, and 100 hole coordinates will be required accordingly. The conventional practice is to record the current encoding value each time a hole is counted during driving, compare it with the theoretical value of the current hole, and extract the difference. For the difference obtained, one way is to accumulate the difference of each hole, and add the total error value directly to the initial destination position in the final positioning stage by integration, and obtain the destination position after correction to achieve the purpose of correction; another way is to correct the deviation of each hole directly to the final destination position for correction. But no matter which method is used, the errors of a single hole when empty and loaded will be accumulated, resulting in a wrong hole when the error is greater than one hole over a long distance, or the hole counting conditions cannot be met, resulting in an inability to correct the deviation. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a four-way vehicle positioning and correction algorithm, which can effectively solve the cumulative errors caused by insufficient mechanical performance and precision, and also ensure the positioning accuracy of a low-cost form such as an ordinary incremental encoder plus counting holes.

[0005] The present invention is achieved through the following technical solutions.

[0006] A four-way vehicle positioning and correction algorithm provided by the present invention comprises the following steps:

[0007] Z1, initial record: initial setting of real-time coding value S1 and theoretical coding value L1;

[0008] Z2, record success value: count the holes of the shelf hole coordinates, store the theoretical code value of successful hole counting into the theoretical value temporary storage L2, and store the actual code value of successful hole counting into the actual value temporary storage S2;

[0009] Z3, calculate the change: calculate the code value change S3 according to the actual value temporary storage S2 and the actual code value S1;

[0010] Z4. Calculate virtual correction value: Calculate theoretical correction value L3 according to theoretical value temporarily stored L2 and coding value change, and substitute theoretical correction value L3 into hole counting program for correction.

[0011] After step Z4, the following steps are also included:

[0012] Z5, calculate the deviation correction value: calculate the actual theoretical difference S4 according to the actual value temporarily stored in S2 and the theoretical value temporarily stored in L2;

[0013] Z6. Calculate the deviation correction value: Calculate the target position correction value L4 based on the actual theoretical difference S4 and the target position L.

[0014] In the step Z3, the coding value variation S3 is calculated as S3=S1-S2.

[0015] In step Z4, the theoretical correction value L3 is calculated as L3 = L2 + S3.

[0016] In step Z5, the actual theoretical difference S4 is calculated as S4=S2-L2.

[0017] In the step Z6, the target position correction value L4 is calculated as L4=L+S4.

[0018] The theoretical coding value L1 and the theoretical value temporary storage L2 are both coding values ​​of the shelf hole coordinates.

[0019] The actual coding value S1 and the actual value temporary storage S2 are both coding values ​​recorded in the four-way vehicle counting hole.

[0020] In the step Z2, successful hole counting means that the shelf hole positions are aligned and the shelf hole position coordinates can be obtained.

[0021] The present invention also provides a computer-readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the above-mentioned four-way vehicle positioning and deviation correction algorithm.

[0022] The beneficial effects of the present invention are: it can effectively solve the cumulative errors caused by insufficient mechanical performance and precision, and also ensure the positioning accuracy of a low-cost form of ordinary incremental encoder plus counting holes; it is simple, reliable, low-cost, precise in positioning, high in fault tolerance, and insensitive to external influences, and can be widely used in shuttle carts. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic diagram of a process of at least one embodiment of the present invention;

[0024] Figure 2 yes Figure 1 Timing diagram of . DETAILED DESCRIPTION

[0025] The technical solution of the present invention is further described below, but the scope of protection claimed is not limited to the description.

[0026] A first embodiment of the present invention relates to Figure 1 A four-way vehicle positioning and correction algorithm shown includes the following steps:

[0027] Z1, initial record: initial setting of real-time coding value S1 and theoretical coding value L1;

[0028] Z2, record success value: count the holes of the shelf hole coordinates, store the theoretical code value of successful hole counting into the theoretical value temporary storage L2, and store the actual code value of successful hole counting into the actual value temporary storage S2;

[0029] Z3, calculate the change: calculate the code value change S3 according to the actual value temporary storage S2 and the actual code value S1;

[0030] Z4. Calculate virtual correction value: Calculate theoretical correction value L3 according to theoretical value temporarily stored L2 and coding value change, and substitute theoretical correction value L3 into hole counting program for correction.

[0031] The core concept of the present invention is to introduce the concept of virtual coding values ​​in order to avoid the problem of inaccurate positioning, to allow the trolley to accurately position over long distances, and to ensure that the positioning of the trolley is as unaffected by external factors as possible. The virtual value is derived from the actual value, but has low sensitivity to external interference, and can achieve undistorted collection of positioning data in space. It is hoped that this set of virtual coding values ​​can be used to replace the actual coding values ​​to enter the hole counting and deviation correction algorithms, so as to facilitate the precise positioning of long-distance operation.

[0032] Based on the above implementation, the virtual code value after correction is used to compare the addresses of different holes, ensuring that the code value with the smallest error is used to query each hole number. The error of a single hole is determined by the size of the cargo position, which determines that there will not be a particularly large error between two holes, so the cumulative error caused by insufficient mechanical performance and precision can be solved. This also ensures the positioning accuracy of the low-cost form of ordinary incremental encoders plus counting holes.

[0033] The second embodiment of the present invention is substantially the same as the first embodiment, mainly in that after step Z4, the following steps are further included:

[0034] Z5, calculate the deviation correction value: calculate the actual theoretical difference S4 according to the actual value temporarily stored in S2 and the theoretical value temporarily stored in L2;

[0035] Z6. Calculate the deviation correction value: Calculate the target position correction value L4 based on the actual theoretical difference S4 and the target position L.

[0036] Furthermore, in step Z5, the actual theoretical difference S4 is calculated as S4=S2-L2.

[0037] Furthermore, in step Z6, the target position correction value L4 is calculated as L4=L+S4.

[0038] The third embodiment of the present invention is substantially the same as the first embodiment, mainly in that, in step Z3, the coding value variation S3 is calculated as S3 = S1 - S2.

[0039] Furthermore, in step Z4, the theoretical correction value L3 is calculated as L3 = L2 + S3.

[0040] Furthermore, the theoretical coding value L1 and the theoretical value temporarily stored L2 are both coding values ​​of the shelf hole coordinates.

[0041] Furthermore, the actual coding value S1 and the actual value temporary storage S2 are both coding values ​​recorded in the four-way vehicle counting hole.

[0042] Furthermore, in step Z2, successful hole counting means that the shelf hole positions are aligned and the shelf hole position coordinates can be obtained.

[0043] The above implementation method is actually applied in the control program of the pallet four-way car in a dense warehouse in a project in Guilin. Since the use of this algorithm, the positioning of the car is almost not limited by mechanical factors such as encoder connection gap, wheel characteristics and large load changes. At present, the four-way car algorithm of this project has been running stably for 1 year. Compared with the previous half-month deviation, it has been beyond the deviation range, which verifies the reliability of the algorithm.

[0044] A fourth embodiment of the present invention relates to a computer-readable storage medium storing a computer program, which implements the above method embodiment when executed by a processor.

[0045] That is, those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including several instructions to enable a device (which can be a single-chip microcomputer, chip, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0046] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present invention, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A four-way vehicle positioning and correction algorithm, characterized in that: The following steps are involved: Z1, initial record: initial setting of real-time coding value S1 and theoretical coding value L1; Z2, record success value: count the holes of the shelf hole coordinates, store the theoretical code value of successful hole counting into the theoretical value temporary storage L2, and store the actual code value of successful hole counting into the actual value temporary storage S2; Z3, calculate the change: calculate the code value change S3 according to the actual value temporary storage S2 and the actual code value S1; Z4. Calculate virtual correction value: Calculate theoretical correction value L3 according to theoretical value temporarily stored L2 and coding value change, and substitute theoretical correction value L3 into hole counting program for correction.

2. The four-way vehicle positioning and correction algorithm as claimed in claim 1, characterized in that: After step Z4, the following steps are also included: Z5, calculate the deviation correction value: calculate the actual theoretical difference S4 according to the actual value temporarily stored in S2 and the theoretical value temporarily stored in L2; Z6. Calculate the deviation correction value: Calculate the target position correction value L4 based on the actual theoretical difference S4 and the target position L.

3. The four-way vehicle positioning and correction algorithm as claimed in claim 1, characterized in that: In the step Z3, the coding value variation S3 is calculated as S3=S1-S2.

4. The four-way vehicle positioning and correction algorithm as claimed in claim 1, characterized in that: In step Z4, the theoretical correction value L3 is calculated as L3 = L2 + S3.

5. The four-way vehicle positioning and deviation correction algorithm as claimed in claim 2, characterized in that: In step Z5, the actual theoretical difference S4 is calculated as S4=S2-L2.

6. The four-way vehicle positioning and correction algorithm as claimed in claim 2, characterized in that: In the step Z6, the target position correction value L4 is calculated as L4=L+S4.

7. The four-way vehicle positioning and correction algorithm as claimed in claim 1, characterized in that: The theoretical coding value L1 and the theoretical value temporary storage L2 are both coding values ​​of the shelf hole coordinates.

8. The four-way vehicle positioning and correction algorithm as claimed in claim 2, characterized in that: The actual coding value S1 and the actual value temporary storage S2 are both coding values ​​recorded in the four-way vehicle counting hole.

9. The four-way vehicle positioning and deviation correction algorithm as claimed in claim 1, characterized in that: In the step Z2, successful hole counting means that the shelf hole positions are aligned and the shelf hole position coordinates can be obtained.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the four-way vehicle positioning and correction algorithm described in any one of claims 1 to 9 is implemented.

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