A method for encoding a surface of a spatial planar target anisotropically

Abstract

The embodiment of the present application discloses a kind of anisotropic encoding mark methods of spatial planar target surface.It includes: positioning mark is respectively arranged in the center point of each division interval in a specific embodiment;Multiple equidistant and surrounding encoding mark are generated in each division interval Positioning mark;The coded radix number is obtained, the number of encoding bits is obtained according to interval design information, and the number of rows and columns of division interval is obtained;Each anisotropic encoding of each division interval is obtained;Encoding marker is set on encoding mark by rule base and positioning marker is set on positioning mark.The embodiment generates anisotropic encoding by encoding base, and sets encoding marker on encoding mark and positioning marker on positioning mark according to anisotropic encoding.The purpose of encoding for division interval is achieved, and accurate positioning of each part of spatial planar target can be realized without relying on active sensor.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of anisotropic coding marking of a planar target surface. More particularly, it relates to a method for anisotropic coding marking of a planar target surface in space. BACKGROUND

[0002] At present, in the fields of space test identification and space failed satellite processing, it is difficult to identify the symmetry surface on the space target and the pose of the space target. The existing technology generally realizes the pose identification and surface part identification of the space target by means of distributing sensors on the target surface, but this method has the following problems: on the one hand, a large number of sensors are needed on the target surface, which has a significant power load and high design complexity; on the other hand, it also increases the weight and design and manufacturing cost of the space target, and is not suitable for non-cooperative targets in space, which greatly limits the application of the space target surface part identification technology and the space target pose identification technology in the fields of space test identification and space failed satellite processing.

[0003] In the process of implementing the present application, the inventors have found that the prior art has at least the following problems: the prior art relies on active signal sensors when identifying the surface part of the space target and the pose of the space target, which has a large power load, is difficult to design and manufacture, and is not conducive to reducing the overall weight and construction cost. SUMMARY

[0004] The present application aims to provide a space planar target surface anisotropic coding marking method which does not rely on signal sensors, has no power consumption and low cost, so as to solve at least one of the problems existing in the prior art.

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0006] The present application provides a space planar target surface anisotropic coding marking method, comprising:

[0007] In response to a first design operation of a user, the camera resolution, a plurality of divided intervals of the space planar target surface, interval design information of each of the divided intervals and the minimum anisotropic coding combination number are acquired respectively;

[0008] The positioning mark is arranged at the center point of each of the divided intervals;

[0009] A plurality of coding mark positions are generated in each of the divided intervals, which are equidistant and surround the positioning mark position;

[0010] In response to a second design operation of a user, the coding information of each of the divided intervals is acquired, and the number of rows and columns of the divided intervals is acquired and a rule base is constructed;

[0011] Inputting the encoding information into the rule base to obtain the coded number of the base, and obtaining the number of encoding bits according to the interval design information;

[0012] Building an encoding library, inputting the coded number of the base, the number of encoding bits, the number of rows and columns of the divided intervals, and the minimum number of anisotropy encoding combinations into the encoding library to obtain the anisotropy encoding of each of the divided intervals;

[0013] Obtaining the encoding configuration of each of the divided intervals in response to a third design operation of the user;

[0014] Inputting the anisotropy encoding and the encoding configuration into the rule base, setting the encoding markers on the encoding marker bits and setting the positioning markers on the positioning marker bits.

[0015] Further, the interval design information includes marker quantity information, size information, and spacing information;

[0016] The marker quantity information is used to determine the number of encoding markers; wherein the number of encoding bits is equal to the sum of the number of encoding marker bits and the number of positioning marker bits; and the number of positioning marker bits is 1;

[0017] The size information includes an encoding size and a positioning size; the encoding size is used to determine the size of the encoding markers; and the positioning size is used to determine the size of the positioning markers;

[0018] The spacing information includes an interval spacing and an encoding spacing; the encoding spacing is used to determine the distance between the encoding marker bits within the divided interval; and the interval spacing is used to determine the shortest vertical distance between the edge of the divided interval and the encoding marker bit closest to the edge of the divided interval within the divided interval.

[0019] Further, the encoding marker size and the positioning marker size respectively satisfy the following conditions:

[0020]

[0021] wherein, r 1 is the encoding marker size, l is the camera resolution, r 2 is the positioning marker size;

[0022] The encoding spacing and the interval spacing respectively satisfy the following conditions:

[0023]

[0024] wherein, d 1 is the encoding spacing, l is the camera resolution, d 2 is the interval spacing;

[0025] The size of the coded marker is not equal to the size of the positioning marker, and the size of the positioning marker is larger than the size of the coded marker.

[0026] Furthermore, the encoded information includes color information and shape information;

[0027] The color information is used to determine the color types used for encoding the coded markers and the positioning markers, respectively;

[0028] The shape information is used to determine the shape type used for encoding the coded marker and the positioning marker, respectively.

[0029] Furthermore, the encoding configuration includes an encoding start point, an encoding end point, and an encoding direction;

[0030] The rule base encodes along the encoding direction from the encoding start point to the encoding end point. The encoding method is to set encoding markers on the encoding marker positions and positioning markers on the positioning marker positions. Along the encoding direction, the numbers corresponding to the anisotropic encoding correspond one-to-one with the numbers corresponding to the combination of the encoding markers and the positioning markers.

[0031] Furthermore, the rule base is used to determine the base of the encoding based on the encoding information, and to encode the positioning marker bit and the encoding marker bit respectively; the rule base includes: a rule base for encoding markers and a rule base for positioning markers.

[0032] Furthermore, the rule base for encoding tokens includes:

[0033] When the number of color information types and the number of shape information types of the encoded marker are both greater than 1, then the encoded marker is formed with color information as high-order bits and shape information as low-order bits, or with color information as low-order bits and shape information as high-order bits.

[0034] According to Formula 1:

[0035] ;

[0036] Calculate the base number when both the number of color information types and the number of shape information types of the coded marker are greater than 1; where, J b1 This is a base number when both the number of color information types and the number of shape information types of the coded marker are greater than 1. x b1 The number of shape information types is defined when both the number of color information types and the number of shape information types of the coded marker are greater than 1; y b1 The number of color information types is defined as the number of color information types and the number of shape information types of the encoded marker both being greater than 1.

[0037] When at least one of the number of color information types and the number of shape information types of the encoded marker is equal to 1, the encoded marker is a combination of color information and shape information.

[0038] According to formula 2:

[0039] +1;

[0040] Calculate the base number when at least one of the number of color information types of the coded marker and the number of shape information types of the coded marker is equal to 1; where J b2 x is a base number when at least one of the number of color information types and the number of shape information types of the coded marker is equal to 1. b2 The number of shape information items is defined as follows: y = 1 when at least one of the number of color information types and the number of shape information types of the coded marker is equal to 1. b2 The number of color information types is defined as the number of color information types of the coded marker and the number of shape information types of the coded marker, where at least one of these is equal to 1.

[0041] Furthermore, the rule base for the location markers includes

[0042] When the number of color information types and the number of shape information types of the positioning marker are both greater than 1, then the positioning marker is formed with color information as high-order bits and shape information as low-order bits, or with color information as low-order bits and shape information as high-order bits.

[0043] According to formula 3:

[0044] J d1 = max(x d1 ,y d1 ) +1;

[0045] Calculate the base number when both the number of color information types and the number of shape information types of the positioning marker are greater than 1; where, J d1 This is a base number when both the number of color information types and the number of shape information types of the positioning markers are greater than 1. x d1 The number of shape information types is defined when both the number of color information types and the number of shape information types of the positioning marker are greater than 1. y d1The number of color information types is defined as the number of color information types when both the number of color information types and the number of shape information types of the positioning marker are greater than 1.

[0046] When at least one of the number of color information types and the number of shape information types of the positioning marker is equal to 1, the positioning marker is a combination of color information and shape information.

[0047] According to formula 4:

[0048] +1;

[0049] Calculate the base number when at least one of the number of color information types of the positioning marker and the number of shape information types of the positioning marker is equal to 1; wherein, J d2 The number is a base-1 number when at least one of the number of color information types and the number of shape information types of the positioning marker is equal to 1. x d2 The number of shape information items is defined when at least one of the number of color information types and the number of shape information types of the positioning marker is equal to 1. y d2 The number of color information types is defined as the number of color information types of the positioning marker and the number of shape information types of the positioning marker, where at least one of these is equal to 1.

[0050] Further, the step of inputting the encoding base, encoding bit length, number of rows and columns of the divided interval, and minimum anisotropic encoding combination number into the encoding library to obtain the anisotropic encoding of each of the divided intervals includes:

[0051] A set of random encoded numbers is generated by generating an encoding library, with the number of rows equal to the number of rows in the interval, the number of columns equal to the number of columns in the interval, the number of bases equal to the encoding base, and the number of bits equal to the encoding bit length.

[0052] Adjacent random codes in the random code set are combined, and the number of random codes in each combination is the minimum number of anisotropic code combinations. The combined random code set is traversed, and it is determined whether each combination of random codes in the random code set is anisotropic. If so, anisotropic codes for each partitioned interval are generated; otherwise, a new combination of random codes is generated, replacing the combination of non-anisotropic random codes in the random code set, and the process returns to this step.

[0053] Wherein, the combination of adjacent random codes in the random code set is any combination of multiple adjacent random codes distributed according to the same rule, and when the combined random codes are anisotropic, the combination is unique in the random code set;

[0054] The minimum number of anisotropic coding combinations is determined by the minimum observation area of ​​the space target and the number of intervals within the minimum observation area. The minimum number of anisotropic coding combinations is 1, and the maximum number does not exceed the number of coding intervals within the minimum observation area. The minimum observation area refers to the minimum camera imaging area of ​​the surface of the spatial planar target under the influence of factors such as sky and ground shadows, observation conditions, and target surface occlusion or defects.

[0055] Furthermore, after inputting the anisotropic encoding and encoding configuration into the rule base, setting encoding markers on the encoding marker bits and setting positioning markers on the positioning marker bits, the method further includes:

[0056] Acquire images of the surface of a spatial planar target using a camera;

[0057] Identify location markers or location marker bits on images and decode them using a rule base to obtain the interval complement.

[0058] Identify coded markers or coded marker bits adjacent to the positioning marker, call the rule base, and decode the coded markers to generate interval codes;

[0059] Merge interval codes and interval complements to obtain interval information codes;

[0060] The interval information code is compared with the anisotropic code on each of the defined intervals to determine the interval in which the interval information code is located;

[0061] If a single interval information code cannot be uniquely paired, then the neighboring interval codes determined by the minimum anisotropic combination number are further combined and paired to determine the partition interval where the interval information code is located.

[0062] The camera position and camera rotation angle are obtained, and the pose of the spatial planar target is obtained according to the interval where the interval information code is located.

[0063] The beneficial effects of this invention are as follows:

[0064] Passive high-precision positioning: Anisotropic codes are generated through a coding library, and coding markers and positioning markers are set on the coding marker bits and positioning marker bits according to the anisotropic codes. This achieves the purpose of coding for dividing intervals, enabling precise positioning of various parts of spatial planar targets without relying on active sensors, and is especially suitable for measuring the surface parts of non-cooperative targets in space.

[0065] Significant anisotropy: A segmented surface coding scheme based on interval division is adopted, which realizes significant anisotropy coding of spatial planar target surfaces by arranging and combining information codes of different intervals composed of coding markers and positioning markers;

[0066] Low marker density: By rationally designing the number of types of interval information codes, the number of types of coded markers and positioning markers, and the size of square blocks, the marker density of the spatial target surface can be minimized without affecting the anisotropic characteristics of the surface. Compared with other methods, it can significantly reduce the impact of markers on the surface characteristics of the target.

[0067] High adaptability to sky and ground shadows and observation conditions: By reasonably designing the reuse rate of interval information codes, it is possible to identify surface parts by observing only one coded marker or positioning marker, which has a strong adaptability to complex sky and ground shadow conditions and observation conditions. Attached Figure Description

[0068] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0069] Figure 1 The diagram illustrates a flowchart of an anisotropic coding and marking method for a spatial planar target surface provided by an embodiment of the present invention.

[0070] Figure 2 This diagram illustrates the encoding marker bits and positioning marker bits within a segmentation range provided in an embodiment of the present invention.

[0071] Figure 3 This diagram illustrates an embodiment of the present invention where anisotropic coding is incorporated into a partitioned interval when both the number of color information types and the number of shape information types are greater than 1.

[0072] Figure 4 This diagram illustrates an embodiment of the present invention where anisotropic coding is incorporated into a partitioned interval when the number of color information types is greater than 1 or the number of shape information types is greater than 1.

[0073] Figure 5 This diagram illustrates the encoding direction according to an embodiment of the present invention.

[0074] Figure 6 This diagram illustrates an embodiment of the present invention for generating random codes and replacing repeating combinations.

[0075] Figure 7 This diagram illustrates the final design result of the encoding information of the coded markers and positioning markers provided in an embodiment of the present invention.

[0076] Figure 8 This diagram illustrates an embodiment of the present invention, showing how to obtain anisotropic codes for each of the partitioned intervals from the encoding library.

[0077] Figure 9This diagram illustrates an embodiment of the present invention, which provides setting coded markers on coded marker bits and setting positioning markers on positioning marker bits according to coded configuration.

[0078] Figure 10 This diagram illustrates how, in an embodiment of the present invention, adjacent random codes in a random code set are combined when the minimum number of anisotropic combinations is 2, and the combined random codes are anisotropic.

[0079] Figure 11 A schematic diagram of the structure of a computer system for implementing the apparatus provided in the embodiments of the present invention is shown. Detailed Implementation

[0080] To more clearly illustrate the present invention, the following description, in conjunction with embodiments and accompanying drawings, further explains the invention. Similar components in the drawings are indicated by the same reference numerals. Those skilled in the art should understand that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of protection of the present invention.

[0081] In view of this, such as Figure 1 As shown, this embodiment of the invention provides a method for anisotropic encoding and marking of the surface of a spatial planar target. It should be noted that the spatial planar target refers to one or more surfaces of the target that are rectangular surfaces under camera projection imaging.

[0082] Includes the following steps:

[0083] Step S1: In response to the user's first design operation, obtain the camera resolution, multiple division intervals of the spatial planar target surface, interval design information of each division interval, and minimum anisotropic coding combination number.

[0084] More specifically, the principles for dividing the area include: dividing the surface of the planar target into several uniformly distributed square areas based on the surface size characteristics and camera resolution; the size of the square areas is based on the premise that one or more square areas can be completely observed when the camera is imaging.

[0085] Step S2, as follows Figure 2 As shown, the positioning markers are respectively set at the center point of each of the divided intervals;

[0086] Step S3: Generate multiple equally spaced coded marker bits surrounding the positioning marker bits within each of the defined intervals;

[0087] Step S4: Respond to the user's second design operation, obtain the encoding information of each of the partitioned intervals, as well as the number of rows and columns of the partitioned intervals, and construct a rule base;

[0088] Step S5: Input the encoding information into the rule base to obtain the encoding base number, and obtain the encoding bit length according to the interval design information;

[0089] Step S6: Construct an encoding library by inputting the encoding base, encoding bit length, number of rows and columns of the partitioned interval, and minimum number of anisotropic encoding combinations into the encoding library to obtain the anisotropic encoding of each partitioned interval.

[0090] Step S7: Respond to the user's third design operation to obtain the encoding configuration of each of the partitioned intervals;

[0091] Step S8: Input the anisotropic coding and coding configuration into the rule base, set the coding marker on the coding marker bit and set the positioning marker on the positioning marker bit.

[0092] More specifically, the positioning markers are used to quickly locate the position of the divided interval, making it easier to identify the coded markers around the positioning markers; while the coded markers are used to encode the divided interval.

[0093] In one possible implementation, the interval design information includes marker quantity information, size information, and spacing information;

[0094] The marker quantity information is used to determine the quantity of coded markers; wherein, the number of coded bits is equal to the sum of the number of coded marker bits and the number of positioning marker bits; the number of positioning marker bits is 1;

[0095] The size information includes coded size and positioning size; the coded size is used to determine the size of the coded marker; the positioning size is used to determine the size of the positioning marker.

[0096] The spacing information includes interval spacing and encoding spacing. The encoding spacing is used to determine the distance between each encoding marker bit within the divided interval, and the interval spacing is used to determine the shortest vertical distance between the edge of the divided interval and the encoding marker bit immediately adjacent to the edge of the divided interval.

[0097] The dimensions of the coded marker and the positioning marker respectively satisfy the following conditions:

[0098]

[0099] Where r1 is the size of the coded marker, l is the camera resolution, and r2 is the size of the positioning marker;

[0100] The encoding spacing and interval spacing respectively satisfy the following conditions:

[0101]

[0102] Where d1 is the encoding spacing, l is the camera resolution, and d2 is the interval spacing;

[0103] The size of the coded marker is not equal to the size of the positioning marker, and the size of the positioning marker is larger than the size of the coded marker.

[0104] In addition to meeting the size requirements of the positioning markers and the coded markers, the size information should also ensure that the size of the positioning marker at the center of the area and the size of the coded markers surrounding the positioning markers are distinguishable, that is, the number of imaging pixels of the positioning markers and the coded markers in the camera's field of view differs by 2 pixels or more.

[0105] In one possible implementation, the encoded information includes color information and shape information;

[0106] The color information is used to determine the color types used for encoding the coded markers and the positioning markers, respectively;

[0107] The shape information is used to determine the shape type used for encoding the coded marker and the positioning marker, respectively.

[0108] More specifically, the color information should ensure that the coded markers and positioning markers are clearly distinguishable from the target surface area other than the markers under camera imaging; the shape information should ensure that the shapes of the coded markers and positioning markers are recognizable under camera imaging.

[0109] The encoding configuration includes the encoding start point, encoding end point, and encoding direction;

[0110] The rule base encodes along the encoding direction from the encoding start point to the encoding end point. The encoding method is to set encoding markers on the encoding marker positions and positioning markers on the positioning marker positions. Along the encoding direction, the numbers corresponding to the anisotropic encoding correspond one-to-one with the numbers corresponding to the combination of the encoding markers and the positioning markers.

[0111] In one possible implementation, the encoding configuration includes an encoding start point, an encoding end point, and an encoding direction;

[0112] Along the coding direction, the numbers corresponding to the anisotropic codes correspond one-to-one with the numbers corresponding to the coding markers and the numbers corresponding to the positioning markers.

[0113] More specifically, after obtaining the anisotropic encoding, the encoding direction and encoding start point of each partition are adjusted according to the user's design requirements. The encoding start point and encoding direction of each partition that are not adjusted by the user are randomly set by the rule base during encoding.

[0114] In one possible implementation, the rule base is used to determine the base of the encoding based on the encoding information, and to encode the positioning marker bit and the encoding marker bit respectively; the rule base includes: a rule base for encoding markers and a rule base for positioning markers.

[0115] In one possible implementation, the rule base for encoding tokens includes:

[0116] When the number of color information types and the number of shape information types of the encoded marker are both greater than 1, then the encoded marker is formed with color information as high-order bits and shape information as low-order bits, or with color information as low-order bits and shape information as high-order bits.

[0117] According to Formula 1:

[0118] ;

[0119] Calculate the base number when both the number of color information types and the number of shape information types of the coded marker are greater than 1; where J b1 x is a base number when both the number of color information types and the number of shape information types of the coded marker are greater than 1. b1 The number of shape information types is defined when both the number of color information types and the number of shape information types of the coded marker are greater than 1; y b1 The number of color information types is defined when both the number of color information types and the number of shape information types of the coded marker are greater than 1; if the coded marker does not exist, the corresponding number is 00.

[0120] More specifically, when the number of color information types and the number of shape information types of the coded marker are both greater than 1, when x b1 When smaller ， The value of each bit in the random subcode corresponding to the shape information generated by the encoding library is less than x. b1 The value of y b1 When the value is small, the value of each bit in the random subcode corresponding to the color information generated by the encoding library is less than y. b1 The value of .

[0121] When at least one of the number of color information types and the number of shape information types of the encoded marker is equal to 1, the encoded marker is a combination of color information and shape information.

[0122] According to formula 2:

[0123] +1 ;

[0124] Calculate the base number when at least one of the number of color information types of the coded marker and the number of shape information types of the coded marker is equal to 1; where J b2 x is a base number when at least one of the number of color information types and the number of shape information types of the coded marker is equal to 1. b2 The number of shape information items is defined as follows: y = 1 when at least one of the number of color information types and the number of shape information types of the coded marker is equal to 1. b2 The number of color information types is defined as the number of color information types and the number of shape information types of the coded marker when at least one of these is equal to 1; where, if the coded marker does not exist, the corresponding number is 0.

[0125] In one possible implementation, the rule base for the location markers includes:

[0126] When the number of color information types and the number of shape information types of the positioning marker are both greater than 1, then the positioning marker is formed with color information as high-order bits and shape information as low-order bits, or with color information as low-order bits and shape information as high-order bits.

[0127] According to formula 3:

[0128] J d1 = max(x d1 ,y d1 )+1；

[0129] Calculate the base number when both the number of color information types and the number of shape information types of the positioning marker are greater than 1; where J d1 x is a base number when both the number of color information types and the number of shape information types of the positioning markers are greater than 1. d1 The number of shape information types is defined when both the number of color information types and the number of shape information types of the positioning marker are greater than 1; y d1 The number of color information types is defined as the number of color information types and the number of shape information types of the positioning markers are both greater than 1.

[0130] More specifically, when the number of color information types and the number of shape information types of the positioning marker are both greater than 1, when x d1 When smaller ， The value of each bit in the random subcode corresponding to the shape information generated by the encoding library is less than x. d1 The value of y d1 When the value is small, the value of each bit in the random subcode corresponding to the color information generated by the encoding library is less than y.d1 The value of . Where, if the location marker does not exist, the corresponding number is 00;

[0131] When at least one of the number of color information types and the number of shape information types of the positioning marker is equal to 1, the positioning marker is a combination of color information and shape information;

[0132] According to formula 4:

[0133] +1;

[0134] Calculate the base number when at least one of the number of color information types of the positioning marker and the number of shape information types of the positioning marker is equal to 1; where J d2 x is a base number when at least one of the number of color information types of the positioning marker and the number of shape information types of the positioning marker is equal to 1. d2 The number of shape information items is defined as follows: y = 1 when at least one of the number of color information types and the number of shape information types of the positioning marker is equal to 1. d2 The number of color information types is defined as the number of color information types of the positioning marker and the number of shape information types of the positioning marker, where at least one of these is equal to 1.

[0135] The base of the encoding is equal to the maximum number of combinations of the shape and color information of the location marker; if the location marker does not exist, the corresponding number is 0.

[0136] In a specific example, the multiple division intervals are square intervals evenly distributed on the surface of the planar target. More specifically, the surface of the empty planar target to be identified is a cylindrical surface. Therefore, to adapt to the curvature characteristics of the cylindrical surface, this embodiment uses square markers to ensure the fit of the shape to the cylindrical surface in each observation direction, while avoiding the need for shape recognition during identification and reducing the complexity of the encoding recognition algorithm.

[0137] More specifically, since the division of the interval is designed in a plane, when it is applied to a spatial planar surface (such as a cylindrical surface), the shape of the coded markers and positioning markers will be distorted due to the surface curvature. Therefore, the shape information should adapt to the curvature of the target surface, that is, the shape (such as a rectangle) should be as small as possible after being applied to the curved surface, so as to improve the extraction accuracy of the camera when taking pictures of spatial planar targets.

[0138] In a specific example, the anisotropic code of an interval is "11 21 00 12 00 00 00 0011", where the last two "11"s are two's complement. This code includes coded markers and positioning markers with 2 elements of color information, 2 elements of shape information, and a 3-ary encoding: black is represented as ternary 1, gold as ternary 2, square as ternary 1, and triangle as ternary 2. The encoding direction is along the path with the most adjacent markers, starting from the top-left coded marker and ending at the positioning marker. The anisotropic code of one interval is then incorporated into the interval division as follows: Figure 3 As shown.

[0139] In a specific example, the anisotropic code of one interval is 120100001, with the last 1 representing the complement of the location marker based on the corresponding rules. The encoding direction is chosen along the path with the most adjacent markers, starting from the top-left coded marker and ending at the location marker, to encode the entire interval. The last 1 is used to complement the location marker based on the same rules. The encoding base is 3, and the number of colors is 2; black markers are denoted as 1, and golden markers as 2. After incorporating the anisotropic code into the interval, as shown... Figure 4 As shown.

[0140] More specifically, in practical applications, in order to improve the ability to adapt to complex sky and ground shadow observation conditions, reduce the requirements for camera resolution, and reduce the complexity of image recognition algorithms, the shape and color information of markers should be minimized.

[0141] In one possible implementation, the step of inputting the encoding base, encoding bit length, number of rows and columns of the divided interval, and minimum anisotropic encoding combination number into the encoding library to obtain the anisotropic encoding of each of the divided intervals includes:

[0142] A set of random encoded numbers is generated by generating an encoding library, with the number of rows equal to the number of rows in the interval, the number of columns equal to the number of columns in the interval, the number of bases equal to the encoding base, and the number of bits equal to the encoding bit length.

[0143] Adjacent random codes in the random code set are combined, and the number of random codes in each combination is the minimum number of anisotropic code combinations. The combined random code set is traversed, and it is determined whether each combined random code in the random code set is anisotropic. If so, anisotropic codes for each partitioned interval are generated; otherwise, a new combination of random codes is generated, replacing the combination of non-anisotropic random codes in the random code set, and the process returns to this step.

[0144] More specifically, the minimum anisotropic coding combination refers to any number of adjacent random coding combinations distributed according to the same rule, where the combination is unique in the set of random codes when the random codes of the combination are anisotropic.

[0145] The minimum number of anisotropic coding combinations is determined by the minimum observation area of ​​the spatial target and the number of intervals within the minimum observation area. The minimum number of anisotropic coding combinations is 1, and the maximum is the number of coding intervals within the minimum observation area. The minimum observation area refers to the minimum area of ​​the spatial planar target surface that the camera can capture.

[0146] In one possible implementation, after constructing and invoking the rule base, inputting the anisotropic encoding and encoding configuration into the rule base, setting encoding markers on the encoding marker bits, and setting positioning markers on the positioning marker bits, the method further includes...

[0147] Acquire images of the surface of a spatial planar target using a camera;

[0148] Identify location markers or location marker bits on images and decode them using a rule base to obtain the interval complement.

[0149] Identify coded markers or coded marker bits adjacent to the positioning marker, call the rule base, and decode the coded markers to generate interval codes;

[0150] Merge interval codes and interval complements to obtain interval information codes;

[0151] The interval information code is compared with the anisotropic code on each of the partitioned intervals to determine the partitioned interval where the interval information code is located; if a single interval information code cannot be uniquely matched, then the neighboring interval codes determined by the minimum anisotropic combination number are further combined and matched to determine the partitioned interval where the interval information code is located.

[0152] The camera position and camera rotation angle are obtained, and the pose of the spatial planar target is obtained according to the interval where the interval information code is located.

[0153] In a specific example, such as Figure 5 As shown, the principles for the decoding direction through rule base decoding are as follows;

[0154] Principle 1: Decoding should prioritize directions with a higher number of adjacent coded markers, such as... Figure 5 a) and b) represent;

[0155] Principle 2: such as Figure 5 As shown in c) and d), based on principle 1, when the encoded markers are symmetrical, there are multiple equivalent decoding directions. The decoding direction can be either clockwise or counterclockwise.

[0156] Principle 3: Building upon Principle 1, when high and low byte markers exist, the decoding direction should be determined first according to the high-low byte priority principle agreed upon during encoding, such as "low byte first" or "high byte first." Figure 5 Taking (e) as an example, the black square marker represents "1" and the gold square marker represents "2". For "lower bit first", the decoding direction is ①; for "higher bit first", the decoding direction is ②.

[0157] In one specific embodiment, such as Figure 6 As shown in a), when it is determined that the random coding combination of the shaded area in the figure is anisotropic, a new random code is generated through the coding library to replace the random coding combination of the shaded area (in the figure, 110010001 on the right is replaced with 110110001). The result after replacement is as follows. Figure 6 As shown in b), return to this step.

[0158] In a specific example, this embodiment uses a size of Taking a cylindrical body as an example, the method for encoding and marking the anisotropy of its cylindrical surface is illustrated. The specific implementation process is as follows:

[0159] Block division: In this embodiment, the maximum projected surface (cross-section) size of the cylinder is... A rectangle, which becomes a cylinder after being flattened. The rectangle is to be divided into square blocks, therefore the number of blocks along the length and width of the rectangle should be the common divisor of the length and width of the rectangle and the size of the blocks. At the same time, to reduce the minimum observation area required for identification in any observation direction, there should be no fewer than two divisions along the length and width of the cross-section. After comprehensive consideration, the designed size of the division interval is a side length l = 1.05m.

[0160] Size and spacing design:

[0161] In this embodiment, the camera resolution is 5cm—that is, the size of one pixel is 5cm. To ensure that it can be identified in the imaging field of view, the marking encoding size, positioning size, encoding spacing and interval spacing should all be no less than 10cm.

[0162] In this embodiment, based on the cylindrical curvature characteristics, square markers are used to ensure the shape's fit to the cylindrical surface in each observation direction, while avoiding the need for shape recognition during encoding and reading, thus reducing the complexity of the encoding and recognition algorithm.

[0163] In this embodiment, an 8-bit coding block is selected;

[0164] In this embodiment, to ensure that the size of the positioning mark and the coding mark can still be clearly identified under diffuse conditions, their minimum size should be no less than 2 pixels; the difference in the number of imaging pixels between the positioning mark and the coding mark should be no less than 2 pixels; in summary, the size of the coding mark is designed to be 15cm, and the size of the positioning mark is designed to be 25cm.

[0165] Based on the above design and considering the uniformity of marker distribution, the final design result of the encoding information for coded markers and positioning markers is as follows: Figure 7 As shown.

[0166] The positioning markers are respectively set at the center point of each of the divided intervals;

[0167] Multiple equally spaced coded marker bits surrounding the positioning marker bits are generated within each of the defined intervals;

[0168] In response to the user's second design operation, the system obtains the encoding information of each partitioned interval, the encoding configuration of each partitioned interval, the number of rows and columns of the partitioned interval, and the minimum number of anisotropic combinations, and constructs a rule base.

[0169] Rule base design: In this embodiment, the background color of the planar target is white; the camera is a color camera, but since color information needs to be realized through paint and materials, considering the economy of the material and paint implementation process and the adaptability to the spatial environment, the commonly used black coating and gold coating are selected as the marking colors. On the one hand, this ensures that the marking and the background color are clearly distinguishable, and on the other hand, it ensures feasibility and spatial environment reliability.

[0170] In this embodiment, the mark shape is designed as a single square shape, which has the best matching with the curvature and directional symmetry of the cylinder.

[0171] In this embodiment, the coding interval within the minimum observation area is 2. To ensure the redundancy of identification, the minimum anisotropic combination number is set to 1 according to the principle that the minimum anisotropic combination number is 1 and the maximum value does not exceed the number of coding intervals within the minimum observation area.

[0172] The encoding information is input into the rule base to obtain the encoding base, and the number of bits in the encoding is obtained according to the interval design information; wherein, the number of rows in the interval is 3 and the number of columns is 6, thus determining that the number of rows in the array is 3 and the number of columns is 6; for example Figure 2 As shown, the number of bits in the encoding is the sum of the positioning mark and the encoding mark, which is 9 bits. In this embodiment, the shape is a single shape, and the color is black and gold. The encoding block is encoded using ternary numbering, with "1" representing a black mark, "2" representing a gold mark, and "0" representing a mark when there is no mark. Therefore, the encoding base is ternary.

[0173] The data in the encoded array a

[18] are as follows:

[0174]

[0175] A total of 18 interval codes;

[0176] Since the minimum number of anisotropic combinations in this embodiment is 1, any random code constitutes a random code combination. The set of random codes is traversed, and it is determined whether each random code in the set is anisotropic. If so, anisotropic codes for each partitioned interval are generated; otherwise, new random codes are generated, replacing the non-anisotropic random codes in the set, and the process returns to this step. Wherein, as... Figure 8 As shown, the data in the array corresponds one-to-one with the anisotropic codes in the generated partition intervals; that is, if the data in the first row and first column of the array is 100000001, then the anisotropic code of the partitioned object is also 100000001.

[0177] Input the anisotropic coding and coding configuration into the rule base, set the coding marker on the coding marker bit and set the positioning marker on the positioning marker bit.

[0178] The encoded spatial planar surface, such as Figure 9 As shown.

[0179] In another specific embodiment where the minimum number of anisotropic combinations is 2, Figure 10 For example, as shown in the figure, the minimum number of anisotropic combinations for a single interval information code is 1. Due to the presence of reused information codes in the figure, anisotropy cannot be guaranteed. Therefore, in this embodiment, the minimum number of anisotropic combinations is 2. First, the random code in the upper left corner is combined with the adjacent random codes (as shown in the figure, the adjacent random codes of 100000001 are 110100001 and 101001001). The random code combination of the random code is obtained. Following this principle, each random code is traversed from top to bottom and from left to right to obtain 18 random code combinations. Each random code has 2 to 4 random code combinations. It is determined whether there is a common random code combination among the 18 random code combinations. If there is, it indicates non-anisotropy; otherwise, it indicates anisotropy.

[0180] The present invention has the following beneficial effects:

[0181] Passive high-precision positioning. Anisotropic codes are generated using a coding library, and coded markers and positioning markers are set on the coding and positioning marker positions based on these codes. This achieves the purpose of encoding segmented areas, enabling precise positioning of various parts of a spatial planar target without relying on active sensors.

[0182] Significant anisotropy is observed. A block-based surface coding scheme based on interval division is adopted, and significant anisotropic coding of spatial planar target surfaces is achieved through the arrangement and combination of random coding sets;

[0183] Low marker density. By rationally designing the number of types of coded markers and positioning markers, and the size of the square blocks, the marker density on the surface of spatial targets can be minimized without affecting the anisotropic characteristics of the surface. Compared with other methods, this can significantly reduce the impact of markers on the surface characteristics of the target.

[0184] It exhibits strong adaptability to various lighting and observation conditions. By rationally designing the reuse rate of coded and positioning markers, it is possible to identify surface parts by observing as little as one interval information code, demonstrating strong adaptability to complex lighting and observation conditions.

[0185] like Figure 11 As shown, a computer system suitable for implementing the spatial planar target surface anisotropic coding and marking method provided in the above embodiments includes a central processing module (CPU), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) or a program loaded from a storage portion into a random access memory (RAM). The RAM also stores various programs and data required for the operation of the computer system. The CPU, ROM, and RAM are connected via a bus. An input / output (I / O) interface is also connected to the bus.

[0186] The following components are connected to the I / O interface: input sections including keyboards, mice, etc.; output sections including liquid crystal displays (LCDs) and speakers, etc.; storage sections including hard disks, etc.; and communication sections including network interface cards such as LAN cards and modems. The communication sections perform communication processing via networks such as the Internet. Drives are also connected to the I / O interface as needed. Removable media, such as disks, optical disks, magneto-optical disks, semiconductor memories, etc., are installed on the drive as needed so that computer programs read from them can be installed into the storage section as required.

[0187] Specifically, according to this embodiment, the process described in the flowchart above can be implemented as a computer software program. For example, this embodiment includes a computer program product comprising a computer program tangibly embodied on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network via a communication component, and / or installed from a removable medium.

[0188] The flowcharts and schematic diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of the system, method, and computer program product of this embodiment. In this regard, each block in the flowchart or schematic diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the schematic diagram and / or flowchart, and combinations of blocks in the schematic diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0189] This embodiment also provides a non-volatile computer storage medium. This non-volatile computer storage medium can be the non-volatile computer storage medium included in the device described in the above embodiments, or it can be a separate non-volatile computer storage medium not assembled into the terminal. The non-volatile computer storage medium stores one or more programs. When the one or more programs are executed by a device, the device causes the device to:

[0190] In response to the user's first design operation, the camera resolution, multiple division intervals of the spatial planar target surface, the encoding information of each division interval, and the encoding configuration of each division interval are obtained respectively.

[0191] The positioning markers are respectively set at the center point of each of the divided intervals;

[0192] Based on the encoding configuration and the encoding information, multiple equally spaced encoding marker bits surrounding the center of the positioning marker are generated within each of the defined intervals;

[0193] Construct an encoding library, and obtain the anisotropic encoding of each of the partitioned intervals from the encoding library;

[0194] Build and invoke the rule base, set the encoding marker on the encoding marker bit and the positioning marker on the positioning marker bit according to the encoding configuration.

[0195] In the description of this invention, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this invention can be understood according to the specific circumstances.

[0196] It should also be noted that in the description of this invention, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0197] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A method for anisotropic coding and marking of a spatial planar target surface, characterized in that, include: In response to the user's first design operation, the camera resolution, multiple division intervals of the spatial planar target surface, interval design information of each division interval, and minimum anisotropic coding combination number are obtained respectively. The positioning markers are respectively set at the center point of each of the divided intervals; Multiple equally spaced coded marker bits surrounding the positioning marker bits are generated within each of the defined intervals; In response to the user's second design operation, the encoding information of each of the partitioned intervals is obtained, as well as the number of rows and columns of the partitioned intervals are obtained, and a rule base is constructed. Input the encoding information into the rule base to obtain the encoding base number, and obtain the encoding bit length according to the interval design information; Construct an encoding library by inputting the encoding base, encoding bit length, number of rows and columns of the divided interval, and minimum number of anisotropic encoding combinations into the encoding library to obtain the anisotropic encoding of each divided interval; Responding to the user's third design operation, obtain the encoding configuration for each of the defined intervals; Input the anisotropic coding and coding configuration into the rule base, set the coding marker on the coding marker bit and set the positioning marker on the positioning marker bit; The interval design information includes the number of markers, their size, and the spacing. The marker quantity information is used to determine the quantity of coded markers; wherein, the number of coded bits is equal to the sum of the number of coded marker bits and the number of positioning marker bits; the number of positioning marker bits is 1; The size information includes coded size and positioning size; the coded size is used to determine the size of the coded marker; the positioning size is used to determine the size of the positioning marker. The spacing information includes interval spacing and encoding spacing. The encoding spacing is used to determine the distance between each encoding marker bit within the divided interval. The interval spacing is used to determine the shortest vertical distance between the edge of the divided interval and the encoding marker bit within the divided interval that is immediately adjacent to the edge of the divided interval. The encoded information includes color information and shape information; The color information is used to determine the color types used for encoding the coded markers and the positioning markers, respectively; The shape information is used to determine the shape type used for encoding the coded marker and the positioning marker, respectively; The rule base is used to determine the base of the encoding based on the encoding information, and to encode the positioning marker bits and the encoding marker bits respectively; the rule base includes: a rule base for encoding markers and a rule base for positioning markers; The step of inputting the encoding base, encoding bit length, number of rows and columns of the divided interval, and minimum anisotropic encoding combination number into the encoding library to obtain the anisotropic encoding of each of the divided intervals includes: A set of random encoded numbers is generated by generating an encoding library, with the number of rows equal to the number of rows in the interval, the number of columns equal to the number of columns in the interval, the number of bases equal to the encoding base, and the number of bits equal to the encoding bit length. Adjacent random codes in the random code set are combined, and the number of random codes in each combination is the minimum number of anisotropic code combinations. The combined random code set is traversed, and it is determined whether each combination of random codes in the random code set is anisotropic. If so, anisotropic codes for each partitioned interval are generated; otherwise, a new combination of random codes is generated, replacing the combination of non-anisotropic random codes in the random code set, and the process returns to this step. Wherein, the combination of adjacent random codes in the random code set is any combination of multiple adjacent random codes distributed according to the same rule, and when the combined random codes are anisotropic, the combination is unique in the random code set; The minimum number of anisotropic coding combinations is determined by the minimum observation area of ​​the space target and the number of intervals within the minimum observation area. The minimum number of anisotropic coding combinations is 1, and the maximum number does not exceed the number of coding intervals within the minimum observation area. The minimum observation area refers to the minimum camera imaging area of ​​the surface of the spatial planar target under the influence of sky light and shadow, observation conditions, and target surface occlusion or defects.

2. The method according to claim 1, characterized in that, The dimensions of the coded marker and the positioning marker respectively satisfy the following conditions: in, r 1 represents the size of the coded marker. l For camera resolution, r 2 represents the size of the positioning mark; The encoding spacing and interval spacing respectively satisfy the following conditions: in, d 1 represents the coding spacing. l For camera resolution, d 2 represents the interval; The size of the coded marker is not equal to the size of the positioning marker, and the size of the positioning marker is larger than the size of the coded marker.

3. The method according to claim 1, characterized in that, The encoding configuration includes the encoding start point, encoding end point, and encoding direction; The rule base encodes along the encoding direction from the encoding start point to the encoding end point. The encoding method is to set encoding markers on the encoding marker positions and positioning markers on the positioning marker positions. Along the encoding direction, the numbers corresponding to the anisotropic encoding correspond one-to-one with the numbers corresponding to the combination of the encoding markers and the positioning markers.

4. The method according to claim 1, characterized in that, The rule base for coded tokens includes: When the number of color information types and the number of shape information types of the encoded marker are both greater than 1, then the encoded marker is formed with color information as high-order bits and shape information as low-order bits, or with color information as low-order bits and shape information as high-order bits. According to Formula 1: ； Calculate the base number when both the number of color information types and the number of shape information types of the coded marker are greater than 1; where, J b1 This is a base number when both the number of color information types and the number of shape information types of the coded marker are greater than 1. x b1 The number of shape information types is defined when both the number of color information types and the number of shape information types of the coded marker are greater than 1. y b1 The number of color information types is defined as the number of color information types and the number of shape information types of the encoded marker both being greater than 1. When at least one of the number of color information types and the number of shape information types of the encoded marker is equal to 1, the encoded marker is a combination of color information and shape information. According to formula 2: +1； Calculate the base number when at least one of the number of color information types of the coded marker and the number of shape information types of the coded marker is equal to 1; wherein, J b2 The base is a number when at least one of the number of color information types and the number of shape information types of the coded marker is equal to 1. x b2 The number of shape information items is defined as the number of color information items and the number of shape information items of the coded marker being equal to at least 1. y b2 The number of color information types is defined as the number of color information types of the coded marker and the number of shape information types of the coded marker, where at least one of these is equal to 1.

5. The method according to claim 1, characterized in that, The rule base for the location markers includes: When the number of color information types and the number of shape information types of the positioning marker are both greater than 1, then the positioning marker is formed with color information as high-order bits and shape information as low-order bits, or with color information as low-order bits and shape information as high-order bits. According to formula 3: J d1 =max(x d1 ,y d1 ) +1； Calculate the base number when both the number of color information types and the number of shape information types of the positioning marker are greater than 1; where, J d1 This is a base number when both the number of color information types and the number of shape information types of the positioning markers are greater than 1. x d1 The number of shape information types is defined when both the number of color information types and the number of shape information types of the positioning marker are greater than 1. y d1 The number of color information types is defined as the number of color information types when both the number of color information types and the number of shape information types of the positioning marker are greater than 1. When at least one of the number of color information types and the number of shape information types of the positioning marker is equal to 1, the positioning marker is a combination of color information and shape information. According to formula 4: +1； Calculate the base number when at least one of the number of color information types of the positioning marker and the number of shape information types of the positioning marker is equal to 1; wherein, J d2 The number is a base-1 number when at least one of the number of color information types and the number of shape information types of the positioning marker is equal to 1. x d2 The number of shape information items is defined when at least one of the number of color information types and the number of shape information types of the positioning marker is equal to 1. y d2 The number of color information types is defined as the number of color information types of the positioning marker and the number of shape information types of the positioning marker, where at least one of these is equal to 1.

6. The method according to claim 1, characterized in that, After inputting the anisotropic encoding and encoding configuration into the rule base, setting encoding markers on the encoding marker bits and setting positioning markers on the positioning marker bits, the method further includes: Acquire images of the surface of a spatial planar target using a camera; Identify location markers or location marker bits on images and decode them using a rule base to obtain the interval complement. Identify coded markers or coded marker bits adjacent to the positioning marker, call the rule base, and decode the coded markers to generate interval codes; Merge interval codes and interval complements to obtain interval information codes; The interval information code is compared with the anisotropic code on each of the partitioned intervals to determine the partitioned interval where the interval information code is located; if a single interval information code cannot be uniquely matched, then the neighboring interval codes determined by the minimum anisotropic combination number are further combined and matched to determine the partitioned interval where the interval information code is located. The camera position and camera rotation angle are obtained, and the pose of the spatial planar target is obtained according to the interval where the interval information code is located.

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