Split type high-precision clamping pin hole expansion type visual calibration target and calibration method

Abstract

This invention relates to a split-type high-precision pin-type expansion hole visual calibration target and calibration method, solving the technical problems of existing visual positioning targets having large structural dimensions, high installation accuracy requirements, and being inconvenient for use, transportation, and storage. The invention includes an expansion hole-type visual calibration target and a pin-type visual calibration target. The expansion hole-type visual calibration target includes an expansion hole bracket, an expansion hole target adhesive plate, and an expansion hole positioning shaft. One end of the expansion hole positioning shaft is fitted with an expansion sleeve top cone and a spring expansion sleeve, and the other end is equipped with an expansion hole tightening knob. The spring expansion sleeve cooperates with the expansion hole positioning shaft and the expansion sleeve top cone to form a double-sloping-plane positioning. The pin-type visual calibration target includes a pin bracket, a pin-type target adhesive plate, and a pin-type positioning bracket. A spring clamping sleeve is embedded in the through hole of the pin-type positioning bracket. The pin-type positioning bracket is equipped with a pin-type tightening knob. The spring clamping sleeve cooperates with the pin-type positioning bracket and the pin-type tightening knob to form a double-sloping-plane positioning.

Description

Technical Field

[0001] This invention relates to a visual positioning target and positioning method in automatic docking technology, specifically to a split-type high-precision pin-type visual calibration target and calibration method. Background Technology

[0002] In the docking of large modules, the two separate modules need to be precisely aligned and tightly fitted together through attitude adjustment, and then securely connected with bolts and nuts. This involves numerous components, large module dimensions, and generally cannot alter the outer surface of the modules, making high-precision module docking and assembly extremely difficult and complex. In recent years, with the development of visual positioning and attitude adjustment technologies, automated docking technology for large modules has gradually been applied.

[0003] For automated docking requiring high precision and reliability, positioning technology based on monocular vision systems is generally employed. This technology requires a vision camera to acquire high-precision visual calibration targets that reflect the feature information of the product's end face, thereby establishing a unified multi-coordinate system model that integrates the segment coordinate system, the visual coordinate system, and the attitude adjustment mechanism coordinate system to achieve a docking accuracy error within ±0.2mm.

[0004] Existing visual calibration targets are typically one-piece structures. For example, Chinese patent CN117629060A discloses a three-point full-contact visual positioning target, including a head target and a body target. During docking surface positioning, the head target is installed on the front docking surface, and the body target is installed on the rear docking surface. The head target includes a target tooling plate and two L-shaped target adhesive plates. The L-shaped target adhesive plates are fixed to the ends of the target tooling plate below the positioning holes, and are used to attach visually captured light spot targets during docking surface positioning. The body target differs from the head target in that the positioning holes are replaced with mounting positioning pins. However, this visual positioning target has drawbacks: its large structural size and high installation accuracy requirements make it inconvenient to use, transport, and store. Summary of the Invention

[0005] The purpose of this invention is to solve the technical problems of existing visual positioning targets having large structural dimensions, high installation accuracy requirements, and being inconvenient to use, transport, and store, and to provide a split-type high-precision pin-and-expansion-hole visual calibration target and calibration method.

[0006] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0007] A split-type high-precision pin-and-hole type visual calibration target is used for visual calibration of the front and rear sections; the front section has pin holes on its front mating surface; the rear section has pins corresponding to the pin holes on its rear mating surface.

[0008] Its special feature is:

[0009] Includes at least two orifice-type visual calibration targets and at least two pin-type visual calibration targets;

[0010] The expansion hole type visual calibration target includes an expansion hole bracket, an expansion hole target adhesive plate set at one end of the expansion hole bracket, and an expansion hole positioning shaft threaded through and connected to the other end of the expansion hole bracket; one end of the expansion hole positioning shaft is fitted with an expansion sleeve top cone and a spring expansion sleeve from the outside to the inside, and the other end is equipped with an expansion hole tightening knob; the plane on which the expansion hole target adhesive plate is located is parallel to the axis of the pin hole; the spring expansion sleeve is used to tighten the pin hole; the shape and size of the expansion hole bracket, as well as the connection position between the expansion hole bracket and the expansion hole target adhesive plate, are all determined according to the shape of the forward compartment.

[0011] One end of the expansion hole positioning shaft is provided with a first outer conical surface with the small end facing inward, and the top cone of the expansion sleeve is provided with a second outer conical surface facing that end; both ends of the spring expansion sleeve are provided with inner conical surfaces, which respectively cooperate with the first outer conical surface and the second outer conical surface to form a double inclined surface positioning;

[0012] The pin-type visual calibration target includes a pin bracket, a pin target adhesive plate set at one end of the pin bracket, and a pin positioning bracket passing through the other end of the pin bracket; a spring clamping sleeve is embedded in the through hole of the pin positioning bracket, and the spring clamping sleeve is used to clamp the pin shaft; the plane on which the pin target adhesive plate is located is parallel to the axis of the pin shaft; the shape and size of the pin bracket, as well as the connection position between the pin bracket and the pin target adhesive plate, are determined according to the shape of the rear compartment.

[0013] One end of the pin positioning bracket has a first inner conical surface, and the other end is equipped with a pin tightening knob. The connecting end of the pin tightening knob extends into the through hole of the pin positioning bracket and is threaded into it. The end of the connecting end has a second inner conical surface. The diameter of the through hole of the pin tightening knob is larger than the diameter of the through hole of the spring clamping sleeve, and the two are coaxially arranged. Both ends of the spring clamping sleeve have outer conical surfaces, which respectively cooperate with the first inner conical surface and the second inner conical surface to form a double-sloping surface positioning.

[0014] Furthermore, the expansion hole bracket is provided with a threaded back plate on the side near the expansion hole tightening knob, and the threaded back plate has a threaded hole coaxial with the through hole of the expansion hole bracket.

[0015] The expansion hole positioning shaft has an external thread in the middle, which mates with the threaded hole in the back plate to form a threaded pair. This structure simplifies the machining process and ensures the accuracy of the through hole of the expansion hole bracket.

[0016] The other end of the pin positioning bracket is provided with an internal thread, and the middle of the connecting end of the pin tightening knob is provided with an external thread. The external thread of the knob and the internal thread of the bracket cooperate to form a threaded pair.

[0017] Furthermore, both the external thread of the positioning shaft and the threaded hole of the back plate are reverse threads for easy operation.

[0018] Furthermore, the expansion hole bracket has a top cone groove on the side away from the expansion hole tightening knob, and a top cone mounting groove that is radially connected to the top cone groove. The expansion sleeve top cone is embedded in the top cone groove and fixed by a set screw set in the top cone mounting groove. The other end of the expansion hole positioning shaft extends into the through hole of the expansion hole tightening knob, and a tightening surface is opened on the other end. The connecting end of the expansion hole tightening knob has a through groove that is radially connected to the through hole, and the tightening surface at the other end of the expansion hole positioning shaft is tightened and fixed by a set screw set in the through groove. These two designs make the structure more compact.

[0019] Furthermore, the expansion hole support is a straight rod, perpendicular to both the plane of the expansion hole target adhesive plate and the axis of the pin hole; the pin clamping support is a straight rod, perpendicular to both the plane of the pin clamping target adhesive plate and the axis of the pin shaft. The expansion hole support and the pin clamping support can also be irregularly shaped to avoid the shape of the corresponding compartment's outer surface, leaving room for operation and imaging, as long as the corresponding plane axes are parallel.

[0020] Furthermore, the spring expansion sleeve is a cylindrical structure with inner conical surfaces at both ends, and elastic grooves facing the other end are alternately opened at both ends along the circumference, so that the cylindrical structure forms a continuous S-shaped elastic structure along the circumference and can expand radially; the spring clamping sleeve is a cylindrical structure with outer conical surfaces at both ends, and elastic grooves facing the other end are alternately opened at both ends along the circumference, so that the cylindrical structure forms a continuous S-shaped elastic structure along the circumference and can contract radially.

[0021] Furthermore, the pin positioning bracket has an annular air chamber in the middle of the through hole. The position of the air chamber corresponds to the maximum diameter position of the spring clamping sleeve and is connected to the through hole through an elastic groove.

[0022] Furthermore, the outer periphery of the pin positioning bracket is provided with a mounting boss, which is fixed to the other end of the pin bracket by screws.

[0023] This invention also provides a split-type high-precision pin-type expansion hole visual calibration method, which is implemented using the above-mentioned split-type high-precision pin-type expansion hole visual calibration target. Its special feature is that it includes the following steps:

[0024] S1, Establish an automated docking system;

[0025] The automatic docking system includes an attitude adjustment mechanism, a vision camera, a perforated vision target, and a pin-type vision target. The perforated vision target is used to center and position the pin holes on the front docking surface, and the pin-type vision target is used to center and position the pin shafts on the rear docking surface. The number of perforated vision targets and pin-type vision targets corresponds to the number of pin holes and pin shafts, respectively.

[0026] S2, place the front section and the rear section on the attitude adjustment mechanism respectively, so that the docking surface of the front section corresponds to the docking surface of the rear section;

[0027] S3, attach the corresponding light spot targets to the perforated target adhesive plate of the perforated visual target and the pin-type visual target adhesive plate respectively;

[0028] S4, Install the expansion hole type visual target in the corresponding pin hole; install the retaining pin type visual target on the corresponding pin shaft;

[0029] S5. The optical spot targets of the expansion hole target adhesive plate and the pin adhesive plate are captured by the vision camera. Based on the distance between the plane of the expansion hole target adhesive plate and the pin hole axis, and the distance between the plane of the pin adhesive plate and the pin axis, the spatial position of each optical spot target is analyzed and calculated to obtain the position of the pin hole and the pin.

[0030] S6, determine whether the positions of the pin hole and pin shaft meet the automatic alignment requirements:

[0031] If satisfied, proceed to step S7;

[0032] If the requirements are not met, the positions of the front and rear sections are corrected using the attitude adjustment mechanism, and the process returns to step S5.

[0033] S7. Remove the perforated visual target and the pin-type visual target, pack them in a box and store them to complete this visual calibration.

[0034] Furthermore, step S4 specifically includes:

[0035] S4-1, Insert the bulging hole positioning shaft of the bulging hole type visual target into the pin hole;

[0036] S4-2, rotate the expansion hole tightening knob to move the expansion hole positioning shaft away from the pin hole, thereby moving the first outer conical surface away from the pin hole, and cooperating with the second outer conical surface to compress the inner conical surfaces at both ends of the spring expansion sleeve;

[0037] S4-3, the spring expansion sleeve deforms and expands under force to center and position the pin hole;

[0038] S4-4, The spring clamping sleeve of the pin-type visual target is fitted onto the pin shaft;

[0039] S4-5, rotate the pin tightening knob to move the pin tightening knob toward the pin shaft, thereby moving the first inner conical surface toward the pin shaft, which in turn compresses the outer conical surfaces at both ends of the spring clamping sleeve with the second inner conical surface.

[0040] S4-6, the spring clamping sleeve deforms under force to center and position the pin.

[0041] The advantages of this invention compared to the prior art are:

[0042] 1. The present invention provides a split high-precision pin-type visual calibration target with expansion hole, which is designed with a split structure of expansion hole type visual target and pin-type calibration target. By positioning with double inclined surfaces of spring expansion sleeve or spring clamping sleeve, double contact line centering is achieved, thereby obtaining the accurate position of pin hole and pin shaft, improving the positioning accuracy, which can reach ±0.2mm.

[0043] 2. The present invention provides a split-type high-precision pin-and-hole type visual calibration target, which has a compact structure and small size, making it convenient for transportation, storage and use, and easy to maintain. It solves the problem that existing visual positioning targets are large in size, making them inconvenient to use, transport and store. In addition, because it is a split structure, even if a single target is damaged, it only needs to be reprocessed individually, resulting in low maintenance difficulty and cost.

[0044] 3. The present invention provides a split-type high-precision pin-and-hole type visual calibration target, which uses a spring expansion sleeve to position the pin hole by expansion and a spring clamping sleeve to position the pin shaft by clamping. The operation is simple and reduces the installation difficulty of the calibration target.

[0045] 4. The present invention provides a split-type high-precision pin-type visual calibration method, which achieves rapid and efficient docking surface positioning by using a split-type visual target with a pin-type calibration target. Attached Figure Description

[0046] Figure 1 This is an installation diagram of an embodiment of a split-type high-precision pin-type expansion hole visual calibration target according to the present invention;

[0047] Figure 2 This is a three-dimensional structural diagram of the perforated visual target in an embodiment of the present invention;

[0048] Figure 3 This is a schematic diagram of the structure of the perforated visual target in an embodiment of the present invention, wherein A is a partial cross-sectional view and B is a partial enlarged view of A;

[0049] Figure 4 This is a schematic diagram of the expansion hole positioning shaft in an embodiment of the present invention, wherein A is a three-dimensional structural view and B is a sectional view;

[0050] Figure 5 This is a schematic diagram of the structure of the spring expansion sleeve in an embodiment of the present invention, wherein A is a three-dimensional structural view and B is a sectional view;

[0051] Figure 6 This is a schematic diagram of the structure of the expansion sleeve top cone in an embodiment of the present invention, wherein A is a three-dimensional structural diagram and B is a sectional view;

[0052] Figure 7 This is a schematic diagram of the installation of the perforated visual target in an embodiment of the present invention;

[0053] Figure 8 This is a three-dimensional structural diagram of the pin-type visual target in an embodiment of the present invention;

[0054] Figure 9 This is a schematic diagram of the structure of the pin-type visual target in an embodiment of the present invention, wherein A is a partial cross-sectional view and B is a partial enlarged view of A;

[0055] Figure 10 This is a schematic diagram of the structure of the pin tightening knob in an embodiment of the present invention, wherein A is a three-dimensional structural view and B is a sectional view;

[0056] Figure 11 This is a schematic diagram of the pin positioning bracket in an embodiment of the present invention, wherein A is a three-dimensional structural view and B is a sectional view;

[0057] Figure 12 This is a three-dimensional structural diagram of the spring clamping sleeve in an embodiment of the present invention;

[0058] Figure 13 This is a schematic diagram of the installation of the pin-type visual target in an embodiment of the present invention;

[0059] Figure 14 This is a schematic diagram of the structure of the light spot target in an embodiment of the present invention.

[0060] Icon labels:

[0061] 1-Forward section, 11-Forward docking surface;

[0062] 2-Aft section, 21-Aft docking surface;

[0063] 3-Expansion-hole type visual target, 31-Expansion-hole bracket, 32-Expansion-hole tightening knob, 33-Expansion-hole target adhesive plate, 34-Expansion-hole positioning shaft, 341-First outer conical surface, 342-Positioning shaft external thread, 35-Spring expansion sleeve, 36-Expansion sleeve top cone, 361-Second outer conical surface, 37-Threaded back plate, 371-Back plate threaded hole;

[0064] 4- Pin-type visual target, 41- Pin bracket, 42- Pin tightening knob, 421- Second inner conical surface, 422- Knob external thread, 43- Pin-type target adhesive plate, 44- Spring clamping sleeve, 45- Pin positioning bracket, 451- First inner conical surface, 452- Bracket internal thread, 453- Air chamber, 454- Mounting boss. Detailed Implementation

[0065] The specific technical solutions in the embodiments of the present invention will be further described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0066] This invention discloses a split-type high-precision pin-type visual calibration target and calibration method, comprising a pin-type visual calibration target and a pin-type visual calibration target. The split-type high-precision design allows the two types of visual targets to be installed on the two mating surfaces according to the hole axis relationship during mating. The specific position of the light spot target is then obtained by taking pictures with a camera, thereby obtaining the relative positional relationship between the mating surfaces.

[0067] Figure 1 A split-type high-precision pin-and-hole visual calibration target is provided for visual calibration of the front section 1 and the rear section 2 in this embodiment of the invention. The front section 1 has two pin holes on its front mating surface 11 and the rear section 2 has two pins corresponding to the pin holes on its rear mating surface 21.

[0068] The embodiments of the present invention include two pore-type visual calibration targets 3 and two pin-type visual calibration targets 4.

[0069] refer to Figures 2-7 The expansion hole type visual calibration target 3 includes an expansion hole bracket 31, an expansion hole target adhesive plate 33 disposed at one end of the expansion hole bracket 31, and an expansion hole positioning shaft 34 threaded through and threaded to the other end of the expansion hole bracket 31. One end of the expansion hole positioning shaft 34 is fitted with an expansion sleeve top cone 36 and a spring expansion sleeve 35 sequentially from the outside in, and the other end is equipped with an expansion hole tightening knob 32. The plane of the expansion hole target adhesive plate 33 is parallel to the axis of the pin hole. The spring expansion sleeve 35 is used to tighten the pin hole. The expansion hole bracket 31 is a straight rod, perpendicular to both the plane of the expansion hole target adhesive plate 33 and the axis of the pin hole.

[0070] The expansion hole bracket 31 has a threaded back plate 37 on one side near the expansion hole tightening knob 32. The threaded back plate 37 has a threaded hole 371 coaxial with the through hole of the expansion hole bracket 31. The expansion hole positioning shaft 34 has an external positioning shaft thread 342 in the middle, which mates with the threaded hole 371 of the back plate to form a threaded pair. Both the external positioning shaft thread 342 and the threaded hole 371 of the back plate are reverse threads for easy tightening.

[0071] refer to Figures 4-6 One end of the expansion hole positioning shaft 34 is provided with a first outer conical surface 341 with the small end facing inward, and the top cone 36 of the expansion sleeve is provided with a second outer conical surface 361 facing this end; both ends of the spring expansion sleeve 35 are provided with inner conical surfaces, which respectively cooperate with the first outer conical surface 341 and the second outer conical surface 361 to form a double inclined surface positioning.

[0072] The expansion hole bracket 31 has a top cone groove on the side away from the expansion hole tightening knob 32, and a top cone mounting groove that is radially connected to the top cone groove. The expansion sleeve top cone 36 is embedded in the top cone groove and fixed by a set screw set in the top cone mounting groove. The other end of the expansion hole positioning shaft 34 extends into the through hole of the expansion hole tightening knob 32, and a tightening surface is provided on the other end. The connecting end of the expansion hole tightening knob 32 has a through groove that is radially connected to the through hole. The tightening surface of the other end of the expansion hole positioning shaft 34 is tightened and fixed by a set screw set in the through groove.

[0073] refer to Figures 8-13 The pin-type visual calibration target 4 includes a pin-holding bracket 41, a pin-holding target adhesive plate 43 disposed at one end of the pin-holding bracket 41, and a pin-holding positioning bracket 45 passing through the other end of the pin-holding bracket 41. A spring-loaded clamping sleeve 44 is embedded in the through hole of the pin-holding positioning bracket 45, which is used to clamp the pin shaft. The plane on which the pin-holding target adhesive plate 43 is located is parallel to the axis of the pin shaft. The pin-holding bracket 41 is a straight rod, perpendicular to both the plane on which the pin-holding target adhesive plate 43 is located and the axis of the pin shaft.

[0074] One end of the pin positioning bracket 45 has a first inner conical surface 451, and the other end is equipped with a pin tightening knob 42. The connecting end of the pin tightening knob 42 extends into the through hole of the pin positioning bracket 45 and is threaded into it. The end of the connecting end has a second inner conical surface 421. The other end of the pin positioning bracket 45 has a bracket internal thread 452, and the middle of the connecting end of the pin tightening knob 42 has a knob external thread 422. The knob external thread 422 and the bracket internal thread 452 cooperate to form a threaded pair. The middle of the through hole of the pin positioning bracket 45 has an annular air cavity 453, and the position of the air cavity 453 corresponds to the position of the maximum diameter of the spring clamping sleeve 44.

[0075] refer to Figures 10-12 The through hole diameter of the clamping pin tightening knob 42 is larger than the through hole diameter of the spring clamping sleeve 44, and the two are coaxially arranged; both ends of the spring clamping sleeve 44 are provided with outer conical surfaces, which respectively cooperate with the first inner conical surface 451 and the second inner conical surface 421 to form a double inclined surface positioning.

[0076] In this embodiment of the invention, the installation orientation of the expansion hole target adhesive plate 33 and the pin-holding target adhesive plate 43 (i.e., their positions relative to the expansion hole bracket 31 and the pin-holding bracket 41) is related to the distance between the front docking surface 11 and the rear docking surface 21, the operating space, and the position of the vision camera, and needs to be determined according to the specific site conditions.

[0077] The spring expansion sleeve 35 is a cylindrical structure with inner conical surfaces at both ends. Elastic grooves facing the other end are alternately opened at both ends along the circumference, so that the cylindrical structure forms a continuous S-shaped elastic structure along the circumference. The spring clamping sleeve 44 is a cylindrical structure with outer conical surfaces at both ends. Elastic grooves facing the other end are alternately opened at both ends along the circumference, so that the cylindrical structure forms a continuous S-shaped elastic structure along the circumference.

[0078] The outer periphery of the pin positioning bracket 45 is provided with a mounting boss 454, which is fixed to the other end of the pin bracket 41 by screws.

[0079] This invention also provides a split-type high-precision pin-type expansion hole visual calibration method, which is implemented using the above-mentioned split-type high-precision pin-type expansion hole visual calibration target. The specific steps are as follows:

[0080] S1, Establish an automated docking system;

[0081] The automatic docking system includes an attitude adjustment mechanism, a vision camera, a perforated vision target 3, and a pin-type vision target 4. The perforated vision target 3 is used to center and position the pin holes on the front docking surface 11, and the pin-type vision target 4 is used to center and position the pin shafts on the rear docking surface 21. The number of perforated vision targets 3 and pin-type vision targets 4 corresponds to the number of pin holes and pin shafts, respectively.

[0082] S2, place the front section 1 and the rear section 2 on the attitude adjustment mechanism respectively, so that the front docking surface 11 and the rear docking surface 21 correspond to each other.

[0083] S3, attach the corresponding light spot targets to the perforated target adhesive plate 33 of the perforated visual target 3 and the pin-type visual target adhesive plate 43 of the pin-type visual target 4, respectively. The attachment reference for the light spot targets is as follows. Figure 14 .

[0084] S4, install the expansion-hole type visual target 3 in the corresponding pin hole; install the retaining pin type visual target 4 on the corresponding pin shaft. Specifically:

[0085] S4-1, Insert the bulging hole positioning shaft 34 of the bulging hole type visual target 3 into the pin hole;

[0086] S4-2, rotate the expansion hole tightening knob 32 to move the expansion hole positioning shaft 34 away from the pin hole, thereby moving the first outer conical surface 341 away from the pin hole, and cooperating with the second outer conical surface 361 to compress the inner conical surfaces at both ends of the spring expansion sleeve 35.

[0087] S4-3, the spring expansion sleeve 35 deforms and expands under force to center and position the pin hole;

[0088] S4-4, the spring clamping sleeve 44 of the pin-type visual target 4 is fitted onto the pin shaft;

[0089] S4-5, rotate the pin tightening knob 42 to move the pin tightening knob 42 toward the direction of the pin shaft, thereby causing the first inner conical surface 451 to move toward the direction of the pin shaft, and cooperate with the second inner conical surface 421 to compress the outer conical surfaces at both ends of the spring clamping sleeve 44.

[0090] S4-6, the spring clamping sleeve 44 deforms under force to center and position the pin.

[0091] The order of the two segments S4-1 to S4-3 and S4-4 to S4-6 can be interchanged, that is, the order in which the expansion hole type visual target 3 and the pin type visual target 4 are installed does not matter.

[0092] S5. The optical spot targets of the expansion hole target adhesive plate 33 and the pin-holding target adhesive plate 43 are captured by the vision camera. Based on the distance between the plane of the expansion hole target adhesive plate 33 and the pin hole axis, and the distance between the plane of the pin-holding target adhesive plate 43 and the pin shaft axis, the spatial position of each optical spot target is analyzed and calculated to obtain the position of the pin hole and the pin shaft.

[0093] S6, determine whether the positions of the pin hole and pin shaft meet the automatic alignment requirements:

[0094] If satisfied, proceed to step S7;

[0095] If the requirements are not met, the positions of the front section 1 and the rear section 2 are corrected through the attitude adjustment mechanism, and the process returns to repeat step S5.

[0096] S7. Remove the perforated visual target 3 and the pin-type visual target 4, pack them in a box and store them to complete this visual calibration.

[0097] The perforated visual target 3 and the pin-type visual target 4 in this embodiment of the invention have a total of four parts, which can be packed together in a customized packaging box, which is significantly smaller in size than the previous customized packaging box for the target.

[0098] The above description is merely one embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any equivalent structural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are included within the scope of patent protection of the present invention.

Claims

1. A split-type high-precision pin-expanded hole type visual calibration target for visual calibration of the front section (1) and the rear section (2); the front section (1) has a pin hole on the front section mating surface (11); the rear section (2) has a pin corresponding to the pin hole on the rear section mating surface (21); Its features are: It includes at least two perforated visual calibration targets (3) and at least two pin-type visual calibration targets (4); The expansion hole type visual calibration target (3) includes an expansion hole bracket (31), an expansion hole target adhesive plate (33) disposed at one end of the expansion hole bracket (31), and an expansion hole positioning shaft (34) threaded through and threaded to the other end of the expansion hole bracket (31); one end of the expansion hole positioning shaft (34) is fitted with an expansion sleeve top cone (36) and a spring expansion sleeve (35) from the outside to the inside, and the other end is provided with an expansion hole tightening knob (32); the plane on which the expansion hole target adhesive plate (33) is located is parallel to the axis of the pin hole; the spring expansion sleeve (35) is used to tighten the pin hole; One end of the expansion hole positioning shaft (34) is provided with a first outer conical surface (341) with the small end facing inward, and the top cone (36) of the expansion sleeve is provided with a second outer conical surface (361) facing this end; both ends of the spring expansion sleeve (35) are provided with inner conical surfaces, which respectively cooperate with the first outer conical surface (341) and the second outer conical surface (361) to form a double inclined surface positioning; The pin-type visual calibration target (4) includes a pin bracket (41), a pin target adhesive plate (43) disposed at one end of the pin bracket (41), and a pin positioning bracket (45) passing through the other end of the pin bracket (41); a spring clamping sleeve (44) is embedded in the through hole of the pin positioning bracket (45), and the spring clamping sleeve (44) is used to clamp the pin shaft; the plane on which the pin target adhesive plate (43) is located is parallel to the axis of the pin shaft; One end of the pin positioning bracket (45) is provided with a first inner conical surface (451), and the other end is provided with a pin tightening knob (42). The connecting end of the pin tightening knob (42) extends into the through hole of the pin positioning bracket (45) and is threadedly engaged with it. The end of the connecting end is provided with a second inner conical surface (421). The diameter of the through hole of the pin tightening knob (42) is larger than the diameter of the through hole of the spring clamping sleeve (44), and the two are coaxially arranged. Both ends of the spring clamping sleeve (44) are provided with outer conical surfaces, which respectively engage with the first inner conical surface (451) and the second inner conical surface (421) to form a double inclined surface positioning.

2. The split-type high-precision pin-type expansion hole visual calibration target according to claim 1, characterized in that: The expansion hole bracket (31) has a threaded back plate (37) on the side near the expansion hole tightening knob (32). The threaded back plate (37) has a back plate threaded hole (371) that is coaxial with the through hole of the expansion hole bracket (31). The expansion hole positioning shaft (34) is provided with a positioning shaft external thread (342) in the middle, and the positioning shaft external thread (342) and the back plate threaded hole (371) cooperate to form a threaded pair; The other end of the pin positioning bracket (45) is provided with a bracket internal thread (452), and the middle part of the connecting end of the pin tightening knob (42) is provided with a knob external thread (422). The knob external thread (422) and the bracket internal thread (452) cooperate to form a threaded pair.

3. The split-type high-precision pin-type expansion hole visual calibration target according to claim 2, characterized in that: The external thread (342) of the positioning shaft and the threaded hole (371) of the back plate are both reverse threads.

4. A split-type high-precision pin-type expansion hole visual calibration target according to claim 3, characterized in that: The expansion hole bracket (31) has a top cone groove on the side away from the expansion hole tightening knob (32), and a top cone mounting groove that is radial and communicates with the top cone groove. The expansion sleeve top cone (36) is embedded in the top cone groove and fixed by a set screw set in the top cone mounting groove. The other end of the expansion hole positioning shaft (34) extends into the through hole of the expansion hole tightening knob (32), and a tightening surface is provided on the other end; the connecting end of the expansion hole tightening knob (32) is provided with a radial through groove that communicates with the through hole, and the tightening surface of the other end of the expansion hole positioning shaft (34) is tightened and fixed by the set screw set in the through groove.

5. A split-type high-precision pin-type expansion hole visual calibration target according to any one of claims 1-4, characterized in that: The expansion hole bracket (31) is a straight rod, which is perpendicular to the plane of the expansion hole target adhesive plate (33) and the axis of the pin hole, respectively; The pin bracket (41) is a straight rod, which is perpendicular to the plane of the pin target adhesive plate (43) and the axis of the pin shaft.

6. A split-type high-precision pin-type expansion hole visual calibration target according to claim 1, characterized in that: The spring expansion sleeve (35) is a cylindrical structure with inner conical surfaces at both ends. Elastic grooves facing the other end are alternately opened at both ends along the circumference, so that the cylindrical structure forms a continuous S-shaped elastic structure along the circumference. The spring clamping sleeve (44) is a cylindrical structure with outer conical surfaces at both ends. Elastic grooves facing the other end are alternately opened at both ends along the circumference, so that the cylindrical structure forms a continuous S-shaped elastic structure along the circumference.

7. A split-type high-precision pin-type expansion hole visual calibration target according to claim 6, characterized in that: The pin positioning bracket (45) has an annular air chamber (453) in the middle of the through hole, and the position of the air chamber (453) corresponds to the position of the maximum diameter of the spring clamping sleeve (44).

8. A split-type high-precision pin-type expansion hole visual calibration target according to claim 7, characterized in that: The outer periphery of the pin positioning bracket (45) is provided with a mounting boss (454), which is fixed to the other end of the pin bracket (41) by screws.

9. A split-type high-precision pin-type expansion hole visual calibration method, implemented using the split-type high-precision pin-type expansion hole visual calibration target as described in any one of claims 1-8, characterized in that... Includes the following steps: S1, Establish an automated docking system; The automatic docking system includes an attitude adjustment mechanism, a vision camera, a perforated vision target (3), and a pin-type vision target (4); the perforated vision target (3) is used to center and position the pin holes on the front docking surface (11), and the pin-type vision target (4) is used to center and position the pin shaft on the rear docking surface (21). The number of perforated vision targets (3) and pin-type vision targets (4) corresponds to the number of pin holes and pin shafts, respectively. S2, place the front section (1) and the rear section (2) on the attitude adjustment mechanism respectively, so that the front docking surface (11) and the rear docking surface (21) correspond to each other; S3, attach the corresponding light spot targets to the perforated target adhesive plate (33) of the perforated visual target (3) and the pin-type visual target (43) respectively; S4, install the expansion hole type visual target (3) in the corresponding pin hole; install the retaining pin type visual target (4) on the corresponding pin shaft; S5. The optical targets of the expansion hole target adhesive plate (33) and the pin-holding target adhesive plate (43) are photographed by a vision camera. Based on the distance between the plane of the expansion hole target adhesive plate (33) and the pin hole axis, and the distance between the plane of the pin-holding target adhesive plate (43) and the pin axis, the spatial position of each optical target is analyzed and calculated to obtain the position of the pin hole and the pin. S6, determine whether the positions of the pin hole and pin shaft meet the automatic alignment requirements: If satisfied, proceed to step S7; If the requirements are not met, the positions of the front section (1) and the rear section (2) are corrected by the attitude adjustment mechanism, and the process returns to step S5. S7, remove the perforated visual target (3) and the pin-type visual target (4), pack them in a box and store them to complete this visual calibration.

10. A split-type high-precision pin-type visual calibration method according to claim 9, characterized in that, Step S4 is as follows: S4-1, insert the bulging hole positioning shaft (34) of the bulging hole type visual target (3) into the pin hole; S4-2, rotate the expansion hole tightening knob (32) to move the expansion hole positioning shaft (34) away from the pin hole, thereby causing the first outer conical surface (341) to move away from the pin hole, and cooperate with the second outer conical surface (361) to squeeze the inner conical surfaces at both ends of the spring expansion sleeve (35); S4-3, the spring expansion sleeve (35) deforms and expands under force to center and position the pin hole; S4-4, the spring clamping sleeve (44) of the pin-type visual target (4) is fitted onto the pin shaft; S4-5, rotate the pin tightening knob (42) to move the pin tightening knob (42) toward the direction of the pin shaft, thereby causing the first inner conical surface (451) to move toward the direction of the pin shaft, and cooperate with the second inner conical surface (421) to squeeze the outer conical surfaces at both ends of the spring clamping sleeve (44); S4-6, the spring clamping sleeve (44) deforms under force to center and position the pin.

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