Error adjustment method and compensation device for attitude change of multi-connecting-rod parallel installation and adjustment

Abstract

The invention relates to the technical field of mechanical installation and adjustment, and provides a compensation method and device for posture changes of multi-connecting-rod parallel installation and adjustment. The method includes the following steps that the design length of the connecting rod assembly is obtained, and the actual length of the connecting rod assembly is measured; according to the actual length and the design length, a buffer base installation and adjustment error model is established; the actual length is substituted into the installation and adjustment error model, and the compensation amount is calculated; disassembling all connecting rod assemblies, and replacing the connecting rod assemblies with the same number of error adjustment compensation devices for adjusting posture change by parallel connection of multiple connecting rods; compensating according to the compensation amount; and all the connecting rod assemblies are installed again, and the adjusting pads are cushioned into the connecting rod assemblies. A compensation device is designed for the compensation method provided by the invention. The technical problem that the posture of the buffer base is reduced due to the fact that the lengths of the connecting rods of the buffer base are different is solved, and the technical effects that the assembly precision is improved, the stability of the buffer base is enhanced, implementation is convenient, and universality is high are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical assembly and adjustment, and in particular to an error method and a compensation device for posture change of multi-link parallel assembly and adjustment. Background Art

[0002] During the installation and adjustment of the multi-link parallel mechanism, due to factors such as manufacturing errors and assembly errors, the actual length of the connecting rod often deviates from the designed length. During the installation and adjustment of the multi-link parallel mechanism, the smaller the adjustment error of the equipment, the smaller the change in the output posture of the equipment. The change in posture will directly affect the motion accuracy and stability of the parallel mechanism. During assembly, the errors in part processing size, measurement size, and assembly will easily cause the length of the connecting rod assembly to be inconsistent. The dimensional deviation between the connecting rods will affect the posture accuracy of the buffer base, thereby affecting the performance of the buffer base and causing quality problems. Therefore, the dimensional accuracy of each connecting rod assembly determines the overall performance change of the entire buffer base, and assembly adjustment is one of the key links in the assembly of the buffer base. Therefore, an effective error compensation method is needed to achieve changes in position and posture.

[0003] The multi-link parallel buffer base used in the prior art includes a top plate, 16 connecting rod assemblies, a bottom plate, and 32 ball hinges. Due to factors such as manufacturing errors and assembly errors, the actual length of the connecting rod assembly often deviates from the designed length. During the multi-link parallel assembly and adjustment process, the smaller the adjustment error of the equipment, the smaller the change in the output posture of the equipment. The change in posture will directly affect the motion accuracy and stability of the parallel mechanism. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the related art. To this end, the present invention provides an error adjustment method and compensation device for attitude change of a multi-link parallel assembly, so as to improve the measurement accuracy and speed up the measurement.

[0005] The present invention provides a method for adjusting the error of a multi-link parallel assembly posture change, comprising the following steps: S1: Obtain the design length of the connecting rod assembly and measure the actual length of the connecting rod assembly; S2: Establish the adjustment error model of the buffer base; S3: Substituting the actual length and the designed length into the assembly error model to calculate the compensation amount; S4: Record the state of the connecting rod assembly before disassembly, remove all the connecting rod assemblies from the multi-link parallel buffer base, and replace them with the same number of multi-link parallel assembly posture change error adjustment and compensation devices; S5: according to the compensation amount, using a multi-link parallel mounted posture change error adjustment and compensation device to implement compensation, adjusting the position of the top plate of the multi-link parallel buffer base, and making an adjustment pad; S6: Install the adjustment pad at the top or bottom of the connecting rod assembly, and then reinstall all the connecting rod assemblies with the adjustment pads installed according to the state before the connecting rod assembly was disassembled, so as to complete the error adjustment of the multi-link parallel assembly posture change.

[0006] According to the present invention, a method for adjusting the error of a multi-link parallel assembly posture change is provided, wherein step S2 comprises: S21: Establish a fixed coordinate system with the center of the buffer base plate as the origin The coordinate system is the direction from the center of the buffer base bottom plate to the edge of the buffer base bottom plate. of The positive direction of the axis is perpendicular to the bottom plate of the buffer base. of Axis positive direction, of The positive direction of the axis can be of axis, of The positive direction of the axis forms a right-handed coordinate system and defines the coordinates of the ball center of the ball hinge above the bottom plate of the buffer base; Establish a dynamic coordinate system with the center of the buffer base top plate as the origin , the direction from the center of the buffer base top plate to the edge of the buffer base top plate is the moving coordinate system of The positive direction of the axis is perpendicular to the top plate of the buffer base. of Axis positive direction, of The positive direction of the axis can be of axis, of The positive direction of the axis forms a right-hand coordinate system and defines the coordinates of the ball center of the ball hinge under the top plate of the buffer base; S22: Establish the dynamic equations of the connecting rod assembly, ball joint clearance error and top plate posture error: in, is the length precision matrix, is the gap accuracy matrix, is the precision error, is the connecting rod assembly length error, is the clearance error of the ball hinge, and the dynamic equation is the assembly error model of the buffer base.

[0007] According to the present invention, a method for adjusting the error of a multi-link parallel assembly posture change is provided, and S22 comprises: in, For the top plate i The first connecting rod assembly corresponds to the first connecting rod assembly below the top plate of the buffer base. i The coordinates of the center of the spherical hinge By the moving coordinate system Convert to the given coordinate system The coordinates of Expressed as i The direction vector of the connecting rod assembly The corresponding unit vector is For the i The coordinates of the ball center of the ball joint above the bottom plate of the buffer base, i is the connecting rod assembly number, express Relative to the moving coordinate system Origin The position vector of Expressed as the moving coordinate system Relative to the fixed coordinate system The rotation matrix of The top plate of the buffer base i The center of the ball joint is in the moving coordinate system The damping vector, Represents matrix transpose.

[0008] According to the present invention, a method for adjusting the error of a multi-link parallel assembly posture change is provided. In step S3, according to the perturbation theory transformation , so that becomes a zero matrix, When is a zero matrix, the corresponding is the compensation amount.

[0009] According to the present invention, a method for adjusting the error of a multi-link parallel installation during posture adjustment is provided, step S5 comprising: using a host computer to control an error adjustment and compensation device for adjusting the posture change of the multi-link parallel installation for adjustment according to the compensation amount of different connecting rod assemblies, and the difference between the length of the error adjustment and compensation device for adjusting the posture change of the multi-link parallel installation and the actual length of the connecting rod assembly is the thickness of the adjustment pad.

[0010] According to the present invention, a method for adjusting the error of a multi-link parallel installation posture change is provided. When the compensation amount has a negative value, all the error adjustment compensation devices for the multi-link parallel installation posture change are first extended by the same length and then adjusted. The extended length is greater than the compensation amount.

[0011] The present invention provides a multi-link parallel assembly posture change error adjustment and compensation device, which is used to execute the multi-link parallel assembly posture change error adjustment method, comprising: a servo motor, a speed reduction mechanism, a rotating part and a movable push rod; The output end of the servo motor is connected to the bottom end of the speed reduction mechanism; The top end of the speed reduction mechanism is connected to the bottom end of the rotating member; A groove is provided inside the rotating member, and a thread is provided on the inner surface of the groove; The outer surface of the movable push rod is provided with a thread, and the thread of the movable push rod is screwed into the groove of the rotating member.

[0012] According to the present invention, there is provided a multi-link parallel assembly error adjustment and compensation device for posture change, which also includes: a guide cylinder, a cylinder body, a bottom cover and a thrust bearing; A rotating member and a movable push rod are installed in the guide cylinder; A servo motor and a speed reduction mechanism are installed in the cylinder body; The bottom cover is mounted on the bottom of the cylinder body; The inner ring of the thrust bearing is connected to the rotating member; The outer ring of the thrust bearing is connected to the cylinder body.

[0013] According to the present invention, a speed reduction mechanism of a multi-link parallel mounted error adjustment and compensation device for attitude change also includes: a first gear, a first gear set, a second gear set, and a second gear; The servo motor shaft hole of the first gear is connected to the output end of the servo motor, and the first gear is used to receive the output of the servo motor; The gear teeth of the first gear set mesh with the gear teeth of the first gear; The bottom end of the shaft of the second gear set is inserted into the shaft hole of the first gear set, and the gear teeth of the second gear set are meshed with the gear teeth of the second gear; The shaft of the second gear is connected to the bottom of the rotating member and is used to transmit the decelerated input of the servo motor to the rotating member.

[0014] According to the present invention, a speed reduction mechanism of a multi-link parallel mounted error adjustment and compensation device for attitude change also includes: a first ball bearing group, a second ball bearing group, a third ball bearing, a bearing pressure cover, a lock nut, a bearing pressure plate and a gear bracket; The gear bracket is installed above the servo motor; The first ball bearing set is mounted on the bottom of the gear bracket, and the bottom end of the shaft of the second gear set is inserted into the inner ring of the first ball bearing set; The second ball bearing set is mounted on the bottom of the bearing gland, and the top end of the shaft of the second gear set is inserted into the inner ring of the second ball bearing set; The third ball bearing is installed at the center of the bearing gland, and the top end of the shaft of the second gear is inserted into the inner ring of the third ball bearing; The lock nut is installed above the inner ring of the third ball bearing and the shaft of the second gear, and is used to lock the top end of the shaft of the second gear and the third ball bearing; The bearing pressure plate is located above the lock nut, and the bearing pressure plate is used to press the lock nut.

[0015] The present invention provides an error adjustment method and compensation device for posture changes of a multi-link parallel assembly. By creating an error adjustment method and designing an error adjustment compensation device for posture changes of a multi-link parallel assembly, the two are combined to achieve: improving motion accuracy, by compensating for the length error of the connecting rod assembly, the motion accuracy of the multi-link parallel mechanism can be significantly improved; enhancing stability, the length of the connecting rod assembly after compensation is closer to the design value, thereby enhancing the stability of the buffer base; easy to implement; the method of the present invention can realize automatic adjustment through an automatic adjustment device, and automatically generate the actual length value of the connecting rod assembly after adjustment; strong versatility, the method is suitable for various types of multi-link parallel mechanisms, and has strong versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the adjustment structure of the buffer base after adjustment according to an embodiment of the present invention.

[0018] Figure 2 It is a flow chart of the method provided by the embodiment of the present invention.

[0019] Figure 3 It is a schematic diagram of the coordinate system of the buffer base according to an embodiment of the present invention.

[0020] Figure 4 It is a schematic diagram of the structure of the automatic adjustment device provided by an embodiment of the present invention.

[0021] Figure 5 It is a schematic diagram of an exploded structure of an automatic adjustment device provided in an embodiment of the present invention.

[0022] Figure 6 It is a schematic diagram of the gear reduction structure of the automatic adjustment device provided in an embodiment of the present invention.

[0023] Reference numerals: 101. Top plate; 102. Connecting rod assembly; 103. Bottom plate; 104. Ball hinge; 105. Adjustment pad; 1. Movable push rod; 2. Guide cylinder; 3. Cylinder body; 4. Bottom cover; 5. Rotating member; 6. Speed ​​reduction mechanism; 61. Gear bracket; 62. First gear; 63. First gear set; 64. Second gear set; 65. Second gear; 66. Bearing cover; 67. Lock nut; 68. Bearing pressure plate; 71. First ball bearing set; 72. Second ball bearing set; 73. Third ball bearing; 8. Servo motor; 9. Thrust bearing. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme in the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0025] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0026] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0027] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0028] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0029] Combine the following Figures 1 to 6 The present invention is described.

[0030] Example like Figure 2 As shown, the embodiment of the present invention proposes a method for adjusting the error of a multi-link parallel assembly posture change, comprising the following steps: S1: Obtain the design length of the connecting rod assembly and measure the actual length of the connecting rod assembly; S2: Establish the adjustment error model of the buffer base; S3: Substituting the actual length and the designed length into the assembly error model to calculate the compensation amount; S4: Record the state of the connecting rod assembly before disassembly, remove all the connecting rod assemblies from the multi-link parallel buffer base, and replace them with the same number of multi-link parallel assembly posture change error adjustment and compensation devices; S5: according to the compensation amount, using a multi-link parallel mounted posture change error adjustment and compensation device to implement compensation, adjusting the position of the top plate of the multi-link parallel buffer base, and making an adjustment pad; S6: Install the adjustment pad at the top or bottom of the connecting rod assembly, and then reinstall all the connecting rod assemblies with the adjustment pads installed according to the state before the connecting rod assembly was disassembled, so as to complete the error adjustment of the multi-link parallel assembly posture change.

[0031] In the embodiment of the present invention, in step S1, the embodiment of the present invention uses a high-precision measuring tool to measure the actual length of each connecting rod assembly.

[0032] In the embodiment of the present invention, in step S2, the embodiment of the present invention establishes an adjustment error model of the buffer base according to the measured actual length and design length of the connecting rod assembly. The specific steps are as follows: Step S21: Figure 3 As shown, a fixed coordinate system is established with the center of the buffer base bottom plate as the origin. The coordinate system is the direction from the center of the buffer base bottom plate to the edge of the buffer base bottom plate. of The positive direction of the axis is perpendicular to the bottom plate of the buffer base. of Axis positive direction, of The positive direction of the axis can be of axis, of The positive direction of the axis forms a right-handed coordinate system and defines the coordinates of the ball center of the ball hinge above the bottom plate of the buffer base; Establish a dynamic coordinate system with the center of the buffer base top plate as the origin , the direction from the center of the buffer base top plate to the edge of the buffer base top plate is the moving coordinate system of The positive direction of the axis is perpendicular to the top plate of the buffer base. of Axis positive direction, of The positive direction of the axis can be of axis, of The positive direction of the axis forms a right-hand coordinate system and defines the coordinates of the ball center of the ball hinge under the top plate of the buffer base.

[0033] Step S22: Due to precision error Mainly caused by the length error of the connecting rod assembly and ball joint clearance error The dynamic equations of the connecting rod assembly, ball hinge clearance error and top plate posture error are established: in, in, For the top plate i The first connecting rod assembly corresponds to the first connecting rod assembly below the top plate of the buffer base. i The coordinates of the center of the spherical hinge By the moving coordinate system Convert to the given coordinate system The coordinates of is the length precision matrix, is the gap accuracy matrix, Expressed as i The direction vector of the connecting rod assembly The corresponding unit vector is For the i The coordinates of the center of the ball joint above the bottom plate of the buffer base. i is the connecting rod assembly number, where i =1,2,…,16. express Relative to the moving coordinate system Origin The position vector of . Among them, and It is not obtained by measurement, but is obtained based on the design principle of the buffer base. Expressed as a moving coordinate system Relative to a fixed coordinate system The rotation matrix of . For the buffer base top plate i The center of the ball joint is in the moving coordinate system In the embodiment of the present invention, for The matrix of order, for The matrix of order, for Matrix of order, for The matrix and for The matrix of order, , and for The matrix of order, for The matrix of order, Represents matrix transpose.

[0034] Taking the 16-link buffer base in the embodiment of the present invention as an example, and Substitute into and middle, is the rotation matrix, the length error of the connecting rod assembly is the difference between the actual length of the connecting rod assembly and the designed length of the connecting rod assembly, The upper limit is 0.01mm and the lower limit is -0.01mm. Substituting the above variables into the buffer base adjustment error model, we can get .

[0035] Due to the calculated It is not a zero matrix. According to the perturbation theory, , so that is a zero matrix, and the corresponding length error is obtained , is the compensation amount of the 16-link.

[0036] The above scheme can calculate the compensation amount in the buffer base installation error model. The calculated compensation amount is positive or negative. However, since the connecting rod assembly can only be extended but not shortened in actual production, the present invention also provides a device to replace the connecting rod assembly to adjust the length error, accurately determine the compensation amount, and then compensate the connecting rod assembly to achieve the design effect of the buffer base and improve the efficiency of installation.

[0037] according to Figure 4 , Figure 5 and Figure 6 As shown, the error adjustment and compensation device for the multi-link parallel installation posture change comprises: a servo motor 8, a speed reduction mechanism 6, a rotating member 5 and a movable push rod 1; The output end of the servo motor 8 is connected to the bottom end of the speed reduction mechanism 6; The top end of the speed reduction mechanism 6 is connected to the bottom end of the rotating member 5; The rotating member 5 is provided with a groove inside, and the inner surface of the groove is provided with a thread; The outer surface of the movable push rod 1 is provided with a thread, and the movable push rod 1 is threadedly screwed into the interior of the groove of the rotating part.

[0038] When the servo motor 8 is driven, the speed of the servo motor 8 is decelerated by the speed reduction mechanism 6, and the power is transmitted to the rotating member 5, so that the rotating member 5 rotates. Through the rotation of the rotating member 5, the thread on the groove inside the rotating member 5 drives the movable push rod 1 to move, so that the device can adjust the balance of the base.

[0039] The present invention provides a multi-link parallel assembly posture change error adjustment and compensation device, which also includes: a guide cylinder 2, a cylinder body 3, a bottom cover 4 and a thrust bearing 9; The guide cylinder 2 is provided with a rotating member 5 and a movable push rod 1; The cylinder body 3 is provided with a servo motor 8 and a speed reduction mechanism 6; The bottom cover 4 is installed at the bottom of the cylinder body 3; The inner ring of the thrust bearing 9 is connected to the rotating member 5; The outer ring of the thrust bearing 9 is connected to the cylinder body 3 .

[0040] The function of the guide cylinder 2 is to fix the combination of the rotating member 5 and the movable push rod 1, and to protect the rotating member 5 and the movable push rod 1 from being damaged by external forces.

[0041] The function of the cylinder body 3 is to facilitate the installation of the servo motor 8, the speed reduction mechanism 6 and the thrust bearing 9, and to protect the servo motor 8, the speed reduction mechanism 6 and the thrust bearing 9 from being damaged by external forces.

[0042] The function of the bottom cover 4 is to facilitate the replacement of damaged parts when the servo motor 8, the speed reduction mechanism 6 and the thrust bearing 9 are damaged.

[0043] The function of the thrust bearing 9 is to reduce the rotational friction between the rotating member 5 and the cylinder body 3 .

[0044] According to the present invention, a speed reduction mechanism 6 of a multi-link parallel mounted error adjustment and compensation device for posture change also includes: a first gear 62, a first gear set 63, a second gear set 64 and a second gear 65; The first gear 62, the first gear set 63, the second gear set 64, and the second gear 65 are all installed in the cylinder body 3; The servo motor shaft hole of the first gear 62 is connected to the output end of the servo motor 8, and the first gear 62 is used to receive the output from the servo motor 8; The gear teeth of the first gear set 63 are meshed and connected with the gear teeth of the first gear 62, and the first gear set 63 is used to reduce the output from the servo motor 8; The bottom end of the shaft of the second gear set 64 is inserted into the shaft hole of the first gear set 63, and the gear teeth of the second gear set 64 are meshed and connected with the gear teeth of the second gear 65. The second gear set 64 is used to reduce the output from the servo motor 8; The second gear 65 is used to input the decelerated servo motor 8 into the transmission rotating member 5 .

[0045] According to the present invention, a speed reduction mechanism 6 of a multi-link parallel mounted error adjustment and compensation device for posture change also includes: a first ball bearing group 71, a second ball bearing group 72, a third ball bearing 73, a bearing pressure cover 66, a lock nut 67, a bearing pressure plate 68 and a gear bracket 61; The gear bracket 61 is installed above the servo motor 8 ; the gear bracket 61 is used to support other components of the speed reduction mechanism 6 .

[0046] The first ball bearing set 71 is installed at the bottom of the gear bracket 61, and the bottom ends of the first gear set 63 and the second gear set 64 are inserted into the inner ring of the first ball bearing set 71; The second ball bearing set 72 is mounted on the bottom of the bearing gland 66, and the top end of the shaft of the second gear set 64 is inserted into the inner ring of the second ball bearing set 72; The third ball bearing 73 is installed at the center of the bearing cover 66, and the top end of the shaft of the second gear 65 is inserted into the inner ring of the third ball bearing 73; The lock nut is installed on the inner ring of the third ball bearing 73 and above the shaft of the second gear 65, and is used to lock the top end of the shaft of the second gear 65 and the third ball bearing 73; The bearing pressure plate 68 is located above the lock nut 67 , and the bearing pressure plate 68 is used to press the lock nut 67 .

[0047] In the embodiment of the present invention, the first gear set 63 is installed along the lower end of the second gear set 64 and connected to the second gear set 64 to form a whole. A group of three first ball bearing groups 71 below the first gear set 63 is installed to the installation position of the first ball bearing group 71 at the bottom of the gear bracket 61. The assembly formed by the first gear set 63 and the second gear set 64 is installed into the hole of the inner ring of the first ball bearing group 71; the three ball bearings below the bearing cover 66, namely the second ball bearing group 72, are installed into the installation position of the second ball bearing group 72 of the bearing cover 66; the third ball bearing 73 above the bearing cover 66 is installed into the The middle position, the upper end shaft of the second gear 65 is installed along the inner ring hole of the third ball bearing 73 at the middle position, and the upper end of the third ball bearing 73 is locked with a lock nut 67, and the bearing pressure plate 68 is installed, and the bearing pressure plate 68 presses the lock nut 67 to form a bearing pressure cover assembly; the bearing pressure cover assembly and the gear bracket 61 are assembled, the upper end shaft of the second gear group 64 passes through the inner ring hole of the second ball bearing group 72, and the lower end circular positioning hole of the bearing pressure cover 66 is fitted with the circular positioning shaft on the outer edge of the upper end of the gear bracket 61 to achieve positioning, and the first gear 62 is installed on the main shaft of the servo motor 8, and then the servo motor 8 is installed along the lower end hole of the gear bracket 61 of the reduction mechanism 6. The first gear 62 is meshed with the first gear group 63, and the first gear group 63 is inserted into the gear bracket 61; the reduction mechanism 6 with the servo motor 8 is installed along the lower end hole of the cylinder body 3, and the upper end shaft of the second gear 65 passes through the upper end hole of the cylinder body and is connected to the rotating member 5. The bottom cover 4 is installed to the lower end of the cylinder body 3 and is threadedly connected to the cylinder body 3 .

[0048] Install the thrust bearing 9 into the thrust bearing positioning hole at the upper end of the cylinder body 3, install the rotating member 5 into the inner ring of the thrust bearing 9, connect the outer ring of the thrust bearing 9 to the cylinder body 3, and screw the movable push rod 1 into the rotating member 5 along the thread. Figure 5As shown, there is a guide groove on the side of the movable push rod 1, and a guide piece is provided on the inner side of the top hole of the guide cylinder 2. The guide piece of the guide cylinder 2 is aligned with the guide groove of the movable push rod 1, installed along the upper end of the rotating member 5, and clamped with the cylinder body 3.

[0049] 16 automatic adjustment devices are connected in parallel to achieve the output posture accuracy of the buffer base to meet the design requirements, determine the compensation amount of the connecting rod assembly 102, and realize the rapid installation and adjustment of the multi-link buffer base.

[0050] First, all the connecting rod assemblies 102 are removed and replaced with an error adjustment and compensation device having the same number of multi-link parallel mountings for adjusting posture changes.

[0051] Secondly, the compensation amount calculated in the buffer base installation error model is imported into the host computer, and the host computer controls the servo motor 8 to rotate, and after the deceleration of the speed reduction mechanism 6, it is transmitted to the rotating member 5, and the rotating member 5 rotates to rotate the movable push rod 1. Due to the guide groove on the side of the movable push rod 1 and the guide piece on the inner side of the top hole of the guide cylinder 2, the rotational motion is converted into a linear motion, so that the movable push rod 1 can move forward and backward. The error adjustment and compensation device for the multi-link parallel installation posture change can accurately adjust the buffer base, so that the error of the buffer base is reduced. When the compensation amount has a negative value, the host computer controls all the multi-link parallel installation posture change error adjustment and compensation devices to extend the same length greater than the compensation amount, and then compensate for reducing the length of the connecting rod assembly 102. The difference between the length of the error adjustment and compensation device for the multi-link parallel installation posture change and the actual length of the connecting rod assembly 102 is the thickness of the adjustment pad 105.

[0052] Finally, since the error adjustment and compensation device for the multi-link parallel assembly posture change cannot replace the connecting rod assembly 102 to provide support and buffering effect for the buffer device, all the connecting rod assemblies are reinstalled, and the adjustment pad 105 is inserted into the connecting rod assembly, and the top plate 101, connecting rod assembly 102, bottom plate 103, ball hinge 104 and adjustment pad 105 of the buffer device are reinstalled to complete the error adjustment of the multi-link parallel assembly posture change. The buffer base adjusted in the embodiment of the present invention is as shown in FIG. Figure 1 As shown, in the embodiment of the present invention, the adjustment pad 105 is installed at the tail end of the connecting rod assembly 102.

[0053] The error method and compensation device for adjusting attitude change of the multi-link parallel assembly adopted in the embodiment of the present invention have the following advantages: 1. Improve motion accuracy: The motion accuracy of the multi-link parallel mechanism can be significantly improved by compensating for the length error of the connecting rod assembly.

[0054] 2. Enhanced stability: The length of the connecting rod assembly after compensation is closer to the design value, thereby enhancing the stability of the buffer base.

[0055] 3. Easy to implement: The method of the present invention can realize automatic adjustment through an automatic adjustment device, and automatically generate the actual length value of the connecting rod assembly after adjustment.

[0056] 4. Strong versatility: this method is applicable to various types of multi-link parallel mechanisms and has strong versatility.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for adjusting the error of a multi-link parallel assembly posture change, characterized in that: The following steps are involved: S1: Obtain the design length of the connecting rod assembly and measure the actual length of the connecting rod assembly; S2: Establish the adjustment error model of the buffer base; S3: Substituting the actual length and the designed length into the assembly error model to calculate the compensation amount; S4: Record the state of the connecting rod assembly before disassembly, remove all the connecting rod assemblies from the multi-link parallel buffer base, and replace them with the same number of multi-link parallel assembly posture change error adjustment and compensation devices; S5: according to the compensation amount, using a multi-link parallel mounted posture change error adjustment and compensation device to implement compensation, adjusting the position of the top plate of the multi-link parallel buffer base, and making an adjustment pad; S6: Install the adjustment pad at the top or bottom of the connecting rod assembly, and then reinstall all the connecting rod assemblies with the adjustment pads installed according to the state before the connecting rod assembly was disassembled, so as to complete the error adjustment of the multi-link parallel assembly posture change.

2. The error adjustment method for multi-link parallel assembly posture change according to claim 1, characterized in that: Step S2 includes: S21: Establish a fixed coordinate system with the center of the buffer base plate as the origin The coordinate system is the direction from the center of the buffer base bottom plate to the edge of the buffer base bottom plate. of The positive direction of the axis is perpendicular to the bottom plate of the buffer base. of Axis positive direction, of The positive direction of the axis can be of axis, of The positive direction of the axis forms a right-handed coordinate system and defines the coordinates of the ball center of the ball hinge above the bottom plate of the buffer base; Establish a dynamic coordinate system with the center of the buffer base top plate as the origin , the direction from the center of the buffer base top plate to the edge of the buffer base top plate is the moving coordinate system of The positive direction of the axis is perpendicular to the top plate of the buffer base. of Axis positive direction, of The positive direction of the axis can be of axis, of The positive direction of the axis forms a right-hand coordinate system and defines the coordinates of the ball center of the ball hinge under the top plate of the buffer base; S22: Establish the dynamic equations of the connecting rod assembly, ball joint clearance error and top plate posture error: in, is the length precision matrix, is the gap accuracy matrix, is the precision error, is the connecting rod assembly length error, is the clearance error of the ball hinge, and the dynamic equation is the assembly error model of the buffer base.

3. The error adjustment method for multi-link parallel assembly posture change according to claim 2, characterized in that: S22 includes: in, For the top plate i The first connecting rod assembly corresponds to the first connecting rod assembly below the top plate of the buffer base. i The coordinates of the center of the spherical hinge According to the moving coordinate system Convert to the given coordinate system The coordinates of Expressed as i The direction vector of the connecting rod assembly The corresponding unit vector is For the i The coordinates of the ball center of the ball joint above the bottom plate of the buffer base, i is the connecting rod assembly number, express Relative to the moving coordinate system Origin The position vector of Expressed as the moving coordinate system Relative to the fixed coordinate system The rotation matrix of The top plate of the buffer base i The center of the ball joint is in the moving coordinate system The damping vector, Represents matrix transpose.

4. The error adjustment method for multi-link parallel assembly posture change according to claim 2 is characterized in that: In step S3, according to the perturbation theory, , so that becomes a zero matrix, When is a zero matrix, the corresponding is the compensation amount.

5. The error adjustment method for multi-link parallel assembly posture change according to claim 1, characterized in that: Step S5 includes: according to the compensation amount of different connecting rod assemblies, using the upper computer to control the error adjustment and compensation device of the multi-link parallel installation to adjust the posture change, and the difference between the length of the error adjustment and compensation device of the multi-link parallel installation and the actual length of the connecting rod assembly is the thickness of the adjustment pad.

6. The error adjustment method for multi-link parallel assembly posture change according to claim 5, characterized in that: When the compensation amount has a negative value, all the error adjustment compensation devices for the multi-link parallel assembly posture change are first extended by the same length and then adjusted, and the extended length is greater than the compensation amount.

7. A device for adjusting and compensating the error of a multi-link parallel assembly for adjusting the posture change, used to execute the method for adjusting the error of a multi-link parallel assembly for adjusting the posture change according to any one of claims 1 to 6, characterized in that: include: Servo motor, reduction mechanism, rotating parts and movable push rod; The output end of the servo motor is connected to the bottom end of the speed reduction mechanism; The top end of the speed reduction mechanism is connected to the bottom end of the rotating member; A groove is provided inside the rotating member, and a thread is provided on the inner surface of the groove; The outer surface of the movable push rod is provided with a thread, and the thread of the movable push rod is screwed into the groove of the rotating member.

8. The error adjustment and compensation device for multi-link parallel assembly posture change according to claim 7, characterized in that: Also includes: Guide cylinder, cylinder body, bottom cover and thrust bearing; A rotating member and a movable push rod are installed in the guide cylinder; A servo motor and a speed reduction mechanism are installed in the cylinder body; The bottom cover is mounted on the bottom of the cylinder body; The inner ring of the thrust bearing is connected to the rotating member; The outer ring of the thrust bearing is connected to the cylinder body.

9. The error adjustment and compensation device for multi-link parallel assembly posture change according to claim 7, characterized in that: The speed reduction mechanism further includes: a first gear, a first gear set, a second gear set and a second gear; The servo motor shaft hole of the first gear is connected to the output end of the servo motor, and the first gear is used to receive the output of the servo motor; The gear teeth of the first gear set mesh with the gear teeth of the first gear; The bottom end of the shaft of the second gear set is inserted into the shaft hole of the first gear set, and the gear teeth of the second gear set are meshed with the gear teeth of the second gear; The shaft of the second gear is connected to the bottom of the rotating member and is used to transmit the decelerated input of the servo motor to the rotating member.

10. The error adjustment and compensation device for attitude change of a multi-link parallel assembly according to claim 9, characterized in that: The deceleration mechanism further comprises: a first ball bearing group, a second ball bearing group, a third ball bearing, a bearing pressure cover, a lock nut, a bearing pressure plate and a gear bracket; The gear bracket is installed above the servo motor; The first ball bearing set is mounted on the bottom of the gear bracket, and the bottom end of the shaft of the second gear set is inserted into the inner ring of the first ball bearing set; The second ball bearing set is mounted on the bottom of the bearing gland, and the top end of the shaft of the second gear set is inserted into the inner ring of the second ball bearing set; The third ball bearing is installed at the center of the bearing gland, and the top end of the shaft of the second gear is inserted into the inner ring of the third ball bearing; The lock nut is installed above the inner ring of the third ball bearing and the shaft of the second gear, and is used to lock the top end of the shaft of the second gear and the third ball bearing; The bearing pressure plate is located above the lock nut, and the bearing pressure plate is used to press the lock nut.

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