Design support device for parallel link mechanisms

Abstract

To provide a design assisting device for a parallel link mechanism which can reduce a work burden on a designer.SOLUTION: A design assisting device for a parallel link mechanism: determines, by the discriminant of a primary inverse kinematics equation in which a combination angle and the angle of an initial attitude of a tool are substituted, whether satisfaction requirements for the parallel link mechanism are satisfied or not; admits, as a primary combination angle, the combination angle determined that the satisfaction requirements are satisfied; selects an attitude angle selected from the primary combination angle and the movable range of the tool, and substitutes it in a secondary inverse kinematics equation; executes a secondary narrow-down determination to determine whether the satisfaction requirements for the parallel link mechanism are satisfied or not by the discriminant of the secondary inverse kinematics equation; selects the other selected attitude angle after the secondary narrow-down determination so as to repeatedly execute the secondary narrow-down determination; and admits, as a secondary combination angle, the primary combination angle determined that the satisfaction requirements are satisfied for the attitude angles of all tools in the movable range of the attitude angle of the tool.SELECTED DRAWING: Figure 18

Description

[Technical Field]

[0001] This invention relates to a design support device for parallel link mechanisms. [Background technology]

[0002] In recent years, parallel link mechanisms have been used in devices such as medical equipment and industrial equipment. As shown in the patent document below, the parallel link mechanism comprises a fixed base, an end effector base separated from the fixed base, and a plurality of link mechanisms connecting the fixed base and the end effector base. A tool is attached to the end effector base. When power is transmitted to at least one of the plurality of link mechanisms, the end effector base tilts around an arbitrary point, changing the orientation of the tool. The tip of the tool then moves on a virtual sphere centered on the arbitrary point. Furthermore, a parallel link mechanism in which an arbitrary point is positioned at the tip of the tool has been considered. In this case, only the orientation of the tool is changed without the tip of the tool moving. Hereinafter, changing the orientation of the tool may be referred to as orientation change. The arbitrary point may also be referred to as the center of rotation. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-24061 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] Incidentally, parallel link mechanisms have design requirements such as the range of motion for changing the tool's posture. And there are countless design variables, such as the angle of each joint and the length of the links, that satisfy these design requirements. Therefore, calculating the design variables for each of these elements by hand would require a great deal of time and effort. For these reasons, there is a need for the development of a device that can narrow down the design variables for each element of a parallel link mechanism.

[0005] This invention has been made in view of the above-mentioned problems, and aims to provide a design support device for a parallel link mechanism that can reduce the burden on designers. [Means for solving the problem]

[0006] To achieve the above objective, a design support device for a parallel link mechanism according to one aspect of the present invention narrows down the design variables that satisfy the range of motion of the required attitude angle of the tool in a parallel link mechanism that performs attitude change around a rotation center on the centerline of the tool. The parallel link mechanism comprises a fixed base, an end effector base that supports the tool, and a plurality of link mechanisms that connect the fixed base and the end effector base. The link mechanism has a base-side joint that is rotatably connected to the fixed base, a base-side link whose one end is connected to the base-side joint, an intermediate joint provided at the other end of the base-side link, a tip-side link whose one end is rotatably connected to the base-side link via the intermediate joint, and a tip-side joint that rotatably connects the other end of the tip-side link to the end effector base. The design variables that are narrowed down are a first angle between the base joint and the intermediate joint, a second angle between the intermediate joint and the tip joint, a third angle between the tip joint and a reference line which is a perpendicular line drawn from the rotation center to the fixed base, and the reference line and the base joint. The range of motion of the required attitude angle of the tool and predetermined angles from which each of the first, second, third, and fourth angles can be set are stored. A plurality of combination angles are prepared, each including the first, second, third, and fourth angles selected from the predetermined angles, wherein at least one of the first, second, third, and fourth angles is different. One of the prepared combination angles is selected. The selected combination angle and the angle of the initial attitude of the tool are substituted into the first inverse kinematic equation. A first-order narrowing determination is performed to determine whether the requirements for the parallel link mechanism are met using the discriminant of the first-order inverse kinematic equation. The combination angle that is determined to satisfy the requirements is designated as the first-order combination angle.After the first narrowing-down determination, the number of combination angles is narrowed down to a number of first combination angles by repeatedly selecting other combination angles from the number of combination angles and performing the first narrowing-down determination again. One first combination angle is selected from the number of first combination angles. A selected posture angle is selected from the range of motion of the tool. The selected first combination angle and the selected posture angle are substituted into the second inverse kinematic equation. A second narrowing-down determination is performed to determine whether the requirements for the parallel link mechanism are met using the discriminant of the second inverse kinematic equation. After the second narrowing-down determination, the selected first combination angle is left as is, and the number of selection posture angles is repeatedly selected from the range of motion of the tool's posture angle and performed the second narrowing-down determination again, thereby determining that the first combination angle that satisfies the requirements for all posture angles of the tool within the range of motion of the tool's posture angle is designated as the second combination angle. Once the secondary narrowing-down determination for one of the selected primary combination angles is completed, the process is repeated by selecting another primary combination angle from the multiple primary combination angles and performing the secondary narrowing-down determination again, thereby narrowing down the multiple primary combination angles to the secondary combination angles.

[0007] According to this disclosure, the design variables for the combined angles (first angle, second angle, third angle, and fourth angle) are narrowed down, reducing the burden on the designer.

[0008] Furthermore, in the design support device for the parallel link mechanism according to one embodiment, the first Jacobian of the first combination angle is calculated when the tool is in the initial position. The second Jacobian of the second combination angle is calculated when the tool is in the selected position angle. The sign function of the first Jacobian and the sign function of the second Jacobian are calculated. A singularity determination is made to determine whether the sign function of the second Jacobian and the sign function of the second Jacobian are equal. The first combination angle that is determined not to be equal is not designated as the second combination angle.

[0009] According to the above configuration, among the multiple combination angles, combination angles containing singularities that prevent control of the parallel link mechanism are excluded. Therefore, the number of combination angles (first angle, second angle, third angle, and fourth angle) is narrowed down, further reducing the burden on the designer.

[0010] Furthermore, in the design support device for the parallel link mechanism according to one embodiment, when the rotation center of the parallel link mechanism is located at the tip of the tool, the range of the third angle included in the combination angle is narrowed to less than 180° from 90°, and the range of the fourth angle is narrowed to less than 90° from 0°.

[0011] According to the above configuration, the combination angles (first angle, second angle, third angle, and fourth angle) are further narrowed down, significantly reducing the burden on the designer.

[0012] Furthermore, in the design support device for the parallel link mechanism according to one embodiment, if the intermediate joint does not move to the opposite side of the fixed base from the rotation center regardless of the orientation of the parallel link mechanism, it is determined whether the Z component of the intermediate joint, with the combination angle substituted, is closer to the fixed base than the rotation center. The combination angle for which it is determined that the Z component of the intermediate joint is not closer to the fixed base than the rotation center is not designated as the first combination angle.

[0013] According to the above configuration, the combination angles (first angle, second angle, third angle, and fourth angle) are further narrowed down, significantly reducing the burden on the designer.

[0014] Furthermore, in the design support device for the parallel link mechanism according to one embodiment, the dimensional conditions, namely the maximum outer diameter of the parallel link mechanism, the maximum height of the parallel link mechanism, and the length of the tool, are stored. One of the secondary combination angles is selected from a plurality of secondary combination angles. The size of the end effector base is calculated based on the third angle included in the selected secondary combination angle and the length of the tool. A third-order narrowing judgment is performed to determine whether the calculated size of the end effector base is less than or equal to the maximum outer diameter of the parallel link mechanism. The secondary combination angle determined to be less than or equal to the maximum outer diameter of the parallel link mechanism is designated as the third-order combination angle. The size of the fixed base is calculated based on the fourth angle included in the third-order combination angle. A fourth-order narrowing judgment is performed to determine whether the calculated size of the fixed base is less than or equal to the required maximum outer diameter of the parallel link mechanism. The third-order combination angle determined to be less than or equal to the maximum outer diameter of the parallel link mechanism is designated as the fourth-order combination angle. If the third narrowing-down determination determines that the maximum outer diameter of the parallel link mechanism is exceeded, and if the fourth narrowing-down determination is completed, the process is repeated to select another second combination angle from the multiple second combination angles and perform the third narrowing-down determination again, thereby narrowing down the multiple second combination angles to the fourth combination angle.

[0015] According to the above configuration, the combination angles (first angle, second angle, third angle, and fourth angle) are further narrowed down, significantly reducing the burden on the designer.

[0016] Furthermore, in the design support device for the parallel link mechanism according to one embodiment, the design variable to be narrowed down is the length of the first extension portion of the base link, from the middle portion of the base link to the portion connected to the base joint. A predetermined settable length of the first extension portion is stored. One of the first extension portion lengths is selected from the predetermined lengths. One of the fourth combination angles is selected from a plurality of fourth combination angles. Based on the selected fourth combination angle and the selected first extension portion length, a first overhang amount is calculated in which the intermediate joint protrudes radially outward. A fifth-order narrowing-down determination is made to determine whether the first overhang amount is less than the maximum radius of half the maximum outer diameter. The first extension portion length for which the first overhang amount is determined to be less than the maximum radius of half the maximum outer diameter is designated as the first progressive first extension portion length. Based on the first progressive first extension portion length and the fourth combination angle, a second overhang amount is calculated in which the tip joint protrudes radially outward the most. A sixth-order narrowing determination is made to determine whether the second overhang amount is less than the maximum radius. The length of the first-stage extension part that is determined to be less than the maximum radius is designated as the length of the second-stage extension part. If the fifth-order narrowing determination determines that the first overhang amount is greater than or equal to half of the maximum radius of the maximum outer diameter, and if the sixth-order narrowing determination is successful, the length of the first extension part corresponding to the fourth-order combination angle is changed to another length, the fifth-order narrowing determination is made, and the sixth-order narrowing determination is made, and so on, until the length of the first extension part corresponding to the fourth-order combination angle is narrowed from the predetermined length to the length of the second-stage extension part. Once the length of the first extension part corresponding to one of the fourth-order combination angles has been narrowed, another fourth-order combination angle is selected from a plurality of fourth-order combination angles, and the length of the second-stage extension part corresponding to the selected other fourth-order combination angle is narrowed.

[0017] According to the above configuration, the length of the first extension corresponding to each combination angle (first angle, second angle, third angle, and fourth angle) is narrowed. Therefore, the burden on the designer is reduced. [Effects of the Invention]

[0018] The parallel link mechanism design support device described herein can reduce the burden on designers. [Brief explanation of the drawing]

[0019] [Figure 1] Figure 1 is a side view of the parallel link mechanism according to the embodiment, viewed from the side. [Figure 2] Figure 2 is a cross-sectional view of each base-side joint cut in the axial direction. [Figure 3] Figure 3 shows the view from the end effector base in the second direction (towards the base joint). [Figure 4] Figure 4 shows the parallel link mechanism (with the tool removed) viewed from the first direction. [Figure 5] Figure 5 is a diagram illustrating the direction indicated by the extension of the rotation axis of each joint. [Figure 6] Figure 6 is a side view showing the parallel link mechanism according to the embodiment in operation. [Figure 7] Figure 7 shows a modified parallel link mechanism, a side view of the operating state. [Figure 8] Figure 8 is a schematic diagram illustrating the various elements of a parallel link mechanism. [Figure 9] Figure 9 is a diagram illustrating the pose transformation matrix of the tool. [Figure 10] Figure 10 is a schematic diagram illustrating the definitions of the end-effector base and fixed base of a parallel link mechanism. [Figure 11] Figure 11 is a schematic diagram illustrating the base link of a parallel link mechanism. [Figure 12] Figure 12 is a simplified version of Figure 11. [Figure 13] Figure 13 is a schematic diagram illustrating the base link of a parallel link mechanism. [Figure 14] Figure 14 is a simplified version of Figure 13. [Figure 15]Figure 15 is a diagram illustrating the amount of overhang of the tip-side link. [Figure 16] Figure 16 is a schematic diagram illustrating the dimensions of the parallel link mechanism. [Figure 17] Figure 17 shows the flow of the narrowing down process in the design support system. [Figure 18] Figure 18 shows the flow of the process for narrowing down combination angles using a discriminant. [Figure 19] Figure 19 shows the flow of narrowing down the combination angle using the initial orientation angle of the tool. [Figure 20] Figure 20 shows the flow of the first-stage filtering decision. [Figure 21] Figure 21 shows the flow of narrowing down the combination angle using the range of motion of the tool's posture angle. [Figure 22] Figure 22 is a diagram showing the flow of the second-stage filtering decision. [Figure 23] Figure 23 shows the refinement flow using the required dimensional conditions. [Figure 24] Figure 24 shows the flow of the first-stage filtering decision. [Modes for carrying out the invention]

[0020] The present invention will now be described in detail with reference to the drawings. However, the present invention is not limited to the embodiments described below. Furthermore, the components in the embodiments below include those easily conceivable by those skilled in the art, those substantially identical, and those within the so-called equivalence range. Moreover, the components invented in the embodiments below can be combined as appropriate.

[0021] Figure 1 is a side view of the parallel link mechanism according to the embodiment, viewed from the side. Figure 2 is a cross-sectional view of each base-side joint cut in the axial direction. Figure 3 is a view from the end effector base in the second direction (towards the base-side joints). Figure 4 is a view of the parallel link mechanism (with the tool removed) from the first direction. Figure 5 is a diagram illustrating the direction indicated by the extension of the rotation axis of each joint. Figure 6 is a side view showing the parallel link mechanism according to the embodiment in operation. Figure 7 is a modified parallel link mechanism, a side view of the operation in operation, viewed from the side.

[0022] First, the basic configuration of the parallel link mechanism according to the embodiment will be described. As shown in Figure 1, the parallel link mechanism 100 of this embodiment comprises a fixed base 1 fixed to a base 101, a plurality of link mechanisms 3 with one end connected to the fixed base 1, a plurality of motors 6 provided on the fixed base 1, and an end effector base 50 connected to the other ends of the plurality of link mechanisms 3.

[0023] The fixed base 1 is plate-shaped. The fixed base 1 extends along the surface 101a of the base 101. The fixed base 1 is fixed to the base 101 by bolts (not shown). The fixed base 1 has a first surface 1a facing the end effector base 50. The first surface 1a is a flat surface. A virtual reference line Z is set in the center of the fixed base 1, extending in the direction normal to the first surface 1a. This reference line Z serves as a reference for arranging each component of the parallel link mechanism 100. In other words, the reference line Z is a fixed coordinate and serves as the reference for a coordinate system based on the base. A fixing part 1b is provided in the center of the first surface 1a of the fixed base 1. The fixing part 1b has a hole 1c that opens toward the end effector base 50 (see Figure 2).

[0024] In the following explanation, the direction parallel to the reference line Z is referred to as the axial direction. Of the axial directions, the direction in which the end effector base 50 is positioned as viewed from the fixed base 1 is referred to as the first direction H1. Of the axial directions, the direction in which the fixed base 1 is positioned as viewed from the end effector base 50 is referred to as the second direction H2. The direction perpendicular to the reference line Z (the direction parallel to the first surface 1a) is referred to as the horizontal direction. In the horizontal direction, the direction away from the reference line Z is referred to as the radially outward direction. In the horizontal direction, the direction toward the reference line Z is referred to as the radially inward direction.

[0025] As shown in Figure 1, the motor 6 is fixed to the first surface 1a of the fixed base 1. There are the same number of motors 6 as there are link mechanisms 3 (3 in total). The three motors 6 are arranged at 120° intervals around the reference line Z. Two bases 4 and 5 are provided on the first surface 1a of the fixed base 1. Base 5 protrudes more in the first direction H1 than base 4. One of the three motors 6 is positioned on the first surface 1a of the fixed base 1. One of the three motors 6 is positioned on base 4. The remaining one of the three motors 6 is positioned on base 5. As a result, the three motors 6 have different axial positions. Hereinafter, the three motors 6 will be referred to as the first motor 7, the second motor 8, and the third motor 9 in order of their position closest to the fixed base 1. The output shaft 7a of the first motor 7 is oriented in the first direction H1. A drive pulley 7b is provided on the output shaft 7a. Similarly, the output shaft 8a of the second motor 8 and the output shaft 9a of the third motor 9 face the first direction H1, and are provided with drive pulleys 8b and 9b.

[0026] In this embodiment, there are three link mechanisms 3. Hereinafter, the three link mechanisms will be referred to as the first link mechanism 10, the second link mechanism 20, and the third link mechanism 30. Each of the link mechanisms 3 (first link mechanism 10, second link mechanism 20, and third link mechanism 30) includes, as common technical application elements, a base-side joint (first base-side joint 11, second base-side joint 21, third base-side joint 31), a base-side link (first base-side link 13, second base-side link 23, third base-side link 33), an intermediate joint (first intermediate joint 14, second intermediate joint 24, third intermediate joint 34), a tip-side link (first tip-side link 15, second tip-side link 25, third tip-side link 35), and a tip-side joint (first tip-side joint 16, second tip-side joint 26, third tip-side joint 36 (not shown in Figure 1; see Figure 4)).

[0027] As shown in Figure 2, the base joints (first base joint 11, second base joint 21, third base joint 31) comprise a cylindrical shaft 2 and cylindrical parts (first cylindrical part 12, second cylindrical part 22, third cylindrical part 32) that rotatably fit onto the shaft 2.

[0028] The shaft 2 extends in the axial direction. The end of the shaft 2 in the second direction H2 is fitted into the hole 1c of the fixing part 1b. As a result, the shaft 2 is integrated with the fixing base 1, and the center of the shaft 2 coincides with the reference line Z. The end of the shaft 2 in the first direction H1 is provided with a retaining part 2b that bulges radially outward from the outer circumferential surface 2a of the shaft 2. This retaining part 2b prevents the first cylindrical part 12, the second cylindrical part 22, and the third cylindrical part 32 from coming off the shaft 2.

[0029] The first cylindrical portion 12 is fitted to the outer circumference of the shaft 2. The inner circumferential surface 12a of the first cylindrical portion 12 is in slidable contact with the outer circumferential surface 2a of the shaft 2. The outer circumferential surface of the first cylindrical portion 12 is provided with a first driven pulley 12b, a first fitted surface 12c, and a first connecting surface 12d, in order from the second direction H2 to the first direction H1. As shown in Figure 1, the first driven pulley 12b is positioned horizontally with respect to the drive pulley 7b of the first motor 7. An endless belt (not shown) is suspended between the first driven pulley 12b and the drive pulley 7b. Therefore, when the first motor 7 is driven, its power is transmitted to the first cylindrical portion 12. The first cylindrical portion 12 then rotates around the shaft 2 (reference line Z). The first fitted surface 12c and the first connecting surface 12d have a circular cross-sectional shape. The end face of the first cylindrical portion 12 in the first direction H1 is provided with a recess 12e that is recessed in the second direction H2. The retaining portion 2b is housed in the recess 12e. In this embodiment, the inner circumferential surface 12a of the first cylindrical portion 12 is in slidable contact with the outer circumferential surface 2a of the shaft 2. However, in order to make the rotation of the first cylindrical portion 12 smoother, the present invention may interpose a bearing between the inner circumferential surface 12a of the first cylindrical portion 12 and the outer circumferential surface 2a of the shaft 2.

[0030] As shown in Figure 2, the second cylindrical portion 22 is fitted to the outer circumference of the first mating surface 12c of the first cylindrical portion 12. The inner circumferential surface 22a of the second cylindrical portion 22 is in slidable contact with the first mating surface 12c. The outer circumferential surface of the second cylindrical portion 22 is provided with a second driven pulley 22b, a second mating surface 22c, and a second connecting surface 22d, in order from the second direction H2 to the first direction H1. As shown in Figure 1, the second driven pulley 22b is positioned horizontally with respect to the drive pulley 8b of the second motor 8. An endless belt (not shown) is suspended between the second driven pulley 22b and the drive pulley 8b. Therefore, when the second motor 8 is driven, its power is transmitted to the second cylindrical portion 22. The second cylindrical portion 22 then rotates around the axis 2 (reference line Z). Furthermore, the second mating surface 22c and the second connecting surface 22d have a circular cross-sectional shape. In this embodiment, the inner circumferential surface 22a of the second cylindrical portion 22 is in slidable contact with the first mating surface 12c of the first cylindrical portion 12. However, in order to make the rotation of the second cylindrical portion 22 smoother, the present invention may interpose a bearing between the inner circumferential surface 22a of the second cylindrical portion 22 and the first mating surface 12c of the first cylindrical portion 12.

[0031] As shown in Figure 2, the third cylindrical portion 32 is fitted to the second mating surface 22c of the second cylindrical portion 22 on its outer circumference. The inner circumferential surface 32a of the third cylindrical portion 32 is in slidable contact with the second mating surface 22c. The outer circumferential surface of the third cylindrical portion 32 is provided with a third driven pulley 32b and a third connecting surface 32c, in order from the second direction H2 to the first direction H1. As shown in Figure 1, the third driven pulley 32b is positioned horizontally with respect to the drive pulley 9b of the third motor 9. An endless belt (not shown) is suspended between the third driven pulley 32b and the drive pulley 9b. Therefore, when the third motor 9 is driven, its power is transmitted to the third cylindrical portion 32. The third cylindrical portion 32 then rotates around the axis 2 (reference line Z). The third connecting surface 32c has a circular cross-sectional shape. In this embodiment, the inner circumferential surface 32a of the third cylindrical portion 32 is in slidable contact with the second mating surface 22c of the second cylindrical portion 22. However, in order to make the rotation of the third cylindrical portion 32 smoother, the present invention may interpose a bearing between the inner circumferential surface 32a of the third cylindrical portion 32 and the second mating surface 22c of the second cylindrical portion 22.

[0032] Furthermore, the endless belt (not shown) suspended between the drive pulley 7b and the first driven pulley 12b, the endless belt (not shown) suspended between the drive pulley 8b and the second driven pulley 22b, and the endless belt (not shown) suspended between the drive pulley 9b and the third driven pulley 32b are all located at different axial positions. Therefore, the endless belts do not interfere with each other.

[0033] As shown in Figure 3, the base links (first base link 13, second base link 23, and third base link 33) extend radially, with one end pointing radially inward and the other end pointing radially outward. One end of the first base link 13 is connected to the first connecting surface 12d of the first cylindrical section 12. One end of the second base link 23 is connected to the second connecting surface 22d of the second cylindrical section 22. One end of the third base link 33 is connected to the third connecting surface 32c of the third cylindrical section 32. The first base link 13, the second base link 23, and the third base link 33 are arranged at 120° intervals around axis 2 when the parallel link mechanism 100 starts operating.

[0034] One end of each of the front-end links (first front-end link 15, second front-end link 25, third front-end link 35) is connected to the other end of each of the base-end links (first base-end link 13, second base-end link 23, third base-end link 33) via intermediate joints (first intermediate joint 14, second intermediate joint 24, third intermediate joint 34). The first front-end link 15, second front-end link 25, and third front-end link 35 are arranged to extend circumferentially around the axis 2 when the parallel link mechanism 100 starts operating.

[0035] The intermediate joints (first intermediate joint 14, second intermediate joint 24, third intermediate joint 34) and the end-side joints (first end-side joint 16, second end-side joint 26, third end-side joint 36) rotatably connect the parts to each other. In this embodiment, they are composed of bolts and nuts. Therefore, the axis of rotation (refer to the extensions of the axis of rotation M1, M2, M3, N1, N2 shown in Figure 5) is the center of the bolt's shaft.

[0036] Furthermore, to allow the bolt shaft to pass through, through holes 15a, 25a, and 35a are provided at the other ends of the tip links (first tip link 15, second tip link 25, and third tip link 35). Similarly, through holes (not shown) are provided at the other ends of the base links (first base link 13, second base link 23, and third base link 33) and at one end of the tip links (first tip link 15, second tip link 25, and third tip link 35).

[0037] Regarding the radial length of the base links, the first base link 13, the second base link 23, and the third base link 33 are the shortest in that order. Similarly, regarding the length of the tip links, the first tip link 15, the second tip link 25, and the third tip link 35 are the shortest in that order. As a result, when the parallel link mechanism 100 is in operation, the first link mechanism 10 moves along the inner circumference of the second link mechanism 20 and the third link mechanism 30. The second link mechanism 20 is on the outer circumference of the first link mechanism 10 and moves along the inner circumference of the third link mechanism 30. The third link mechanism 30 moves along the outer circumference of the first link mechanism 10 and the second link mechanism 20. In other words, the three link mechanisms 3 do not come into contact with each other.

[0038] The base links (first base link 13, second base link 23, third base link 33) and tip links (first tip link 15, second tip link 25, third tip link 35) are bent as appropriate to avoid contact with the cylindrical parts (12, 22, 32) and the tool 110. In detail, each of the base links (first base link 13, second base link 23, third base link 33) has a bent middle section, as shown in the second base link 23 in Figure 1. Thus, the base links have a first extended section 104 that extends linearly from the tip joint to the middle section, and a second extended section 105 that extends linearly from the middle section to the middle joint.

[0039] As shown in Figure 4, the end effector base 50 comprises a circular plate-shaped main body 51, a protruding portion 52 that extends radially outward from the outer circumference of the main body 51, and a support portion 53 provided in the center of the main body 51.

[0040] As shown in Figure 1, the main body 51 extends horizontally when the parallel link mechanism 100 starts operating. The surface of the main body 51 in the first direction H1 is the first surface 51a facing the direction of the tip side of the tool 110. The surface of the main body 51 in the second direction H2 is the opposing surface 51b facing the fixed base 1.

[0041] As shown in Figure 4, a base 54 is provided at the radially outer end of the protrusion 52. Each base 54 is connected to the other end of the tip-side links (first tip-side link 15, second tip-side link 25, third tip-side link 35) via tip-side joints (first tip-side joint 16, second tip-side joint 26, third tip-side joint 36). Furthermore, the base 54 is inclined such that the extensions of the rotation axes of the tip-side joints (first tip-side joint 16, second tip-side joint 26, third tip-side joint 36) (see N1 and N2 shown in Figure 5) point toward the end of the tool 110 in the first direction H1 (the tip P side of the tool 110).

[0042] The support portion 53 has a retaining hole 53a that penetrates axially and is cylindrical in shape. The support portion 53 is provided on the first surface 51a of the main body portion 51. The retaining hole 53a penetrates the main body portion 51. The tool 110 is inserted into the retaining hole 53a and fitted into the retaining hole 53a. As shown in Figure 1, the tool 110 penetrates the end effector base 50. In other words, the tool 110 protrudes in the second direction H2 beyond the opposing surface 51b. The support portion 53 is also provided with a bolt 53b that penetrates the support portion 53 radially. The bolt 53b is screwed into the support portion 53. Rotating the bolt 53b changes the amount it protrudes into the retaining hole 53a. The tool 110 is held in place by this bolt 53b so that it does not fall out of the retaining hole 53a.

[0043] Tool 110 has a shape in which the end in the first direction H1 bulges radially outward. The end face of tool 110 in the first direction H1 is a circular flat surface. The center of the end face of tool 110 in the first direction H1 lies on the reference line Z. Hereinafter, the center of the end face of tool 110 in the first direction H1 will be referred to as the tip P.

[0044] Next, the details of the parallel link mechanism 100 will be described. When at least one motor 6 is driven, the end effector base 50 tilts, changing the orientation of the tool 110 (see Figure 6). When the parallel link mechanism 100 is in operation, the end effector base 50 and the tool 110 tilt around an arbitrary point. This arbitrary point is the intersection where the extensions of the rotation axes of each joint intersect. Next, the intersection (arbitrary point) where the extensions of the rotation axes of each joint intersect will be described.

[0045] As shown in Figure 5, the rotation axes of the first base joint 11, the second base joint 21, and the third base joint 31 coincide with the reference line Z. Therefore, the extensions of the rotation axes of the first base joint 11, the second base joint 21, and the third base joint 31 pass through the tip P of the tool 110. The extension line M1 of the rotation axis of the first intermediate joint 14, the extension line M2 of the rotation axis of the second intermediate joint 24, and the extension line M3 of the rotation axis of the third intermediate joint 34 intersect at the tip P of the tool 110. The extension line N1 of the rotation axis of the first tip joint 16, the extension line N2 of the rotation axis of the second tip joint 26, and the extension line N3 of the rotation axis of the third tip joint 36 (not shown in this embodiment; see extension line N3 in Figure 7 of the modified example) intersect at the tip P of the tool 110. From the above, the extensions of the rotation axes of each base joint, each intermediate joint, and each tip joint intersect at the tip P of the tool 110. Therefore, in this embodiment, any point is at the tip P of the tool 110. Consequently, as shown in Figure 6, when the parallel link mechanism 100 of this embodiment is activated, the tool 110 changes its attitude around the tip P. Therefore, the position of the tip P of the tool 110 does not change.

[0046] The parallel link mechanism of this disclosure is not limited to the parallel link mechanism 100 described above. A modified parallel link mechanism 100A will be described. In the embodiments, components that are technically the same as those described are denoted by the same reference numerals as in the embodiments, and detailed descriptions are omitted.

[0047] As shown in Figure 7, the modified parallel link mechanism 100A differs from the parallel link mechanism 100 of the embodiment in that it does not have a motor 6. Furthermore, the modified parallel link mechanism 100A differs from the parallel link mechanism 100 of the embodiment in that the base-side joints (11A, 21A, 31A) are not coaxial. The differences will be explained below in detail.

[0048] In a modified example, the motor is provided on the device (or base) (not shown) to which the parallel link mechanism 100A is fixed. The three link mechanisms 3 (10, 20, 30) are then operated by power transmitted from the motor on the device (or base) (not shown). Thus, the parallel link mechanism of the present invention does not necessarily have to be equipped with a motor. There are no particular restrictions on the positions of the three motors installed on the device (not shown) to which the parallel link mechanism 100A is fixed.

[0049] Each base-side joint (11A, 21A, 31A) is distributed on the first surface a of the fixed base 1. Furthermore, the extensions of the rotation axes of each base-side joint (11A, 21A, 31A) (only the extension L of the rotation axis of the first base-side joint 11A is shown in Figure 7) intersect with each other at the tip P of the tool 110. Thus, even with the modified parallel link mechanism 100A, the end effector base 50 tilts around the tip P of the tool 110. Therefore, the position of the tip P of the tool 110 does not change.

[0050] Next, a design support device for parallel link mechanisms will be described. A design support device for parallel link mechanisms is comprised of, for example, a computer (information processing device). Examples of computers include personal computers and tablet devices. The computer functions as a design support device by executing a program. The program may be stored in the computer's internal memory or in an external storage device.

[0051] Furthermore, the parallel link mechanism design support device comprises a main unit, an input unit, and a display unit. Examples of input units include keyboards, mice, and touch panels. Examples of display units include displays, touch panels, and printers. The main unit also comprises a processing unit and a storage unit. The processing unit is realized, for example, by a hardware processor such as a CPU (Central Processing Unit) executing a program (software) stored in the storage unit. Alternatively, it may be realized through the cooperation of software and hardware. The program may be pre-stored in a storage device such as an HDD (Hard Disk Drive) or flash memory (a storage device with a non-transient storage medium), or it may be stored in a removable storage medium such as a DVD or CD-ROM (a non-transient storage medium) and installed when the storage medium is mounted in a drive device.

[0052] Next, we will explain the terminology used in the description of the parallel link mechanism design support device. Each term is defined as shown in Table 1 below.

[0053] [Table 1]

[0054] FIG. 8 is a schematic diagram for explaining each element of the parallel link mechanism. As shown in FIG. 8, in the coordinate system, the direction parallel to the reference line Z is defined as "Z0". Therefore, one direction orthogonal to the reference line Z is defined as "X0". Further, the direction orthogonal to both "X0" and "Z0" is defined as "Y0".

[0055] As shown in FIG. 8 and Table 1, "i" is the index of the chain (link mechanism) that connects the fixed base 1 and the end effector base 50. In the embodiment, since there are three link mechanisms, "i" can be either 1, 2, or 3. When i = 1, the first link mechanism 10 is shown. When i = 2, the second link mechanism 20 is shown. When i = 3, the third link mechanism 30 is shown.

[0056] "u i " is the direction vector of the base side joint. "w i " is the direction vector of the intermediate joint. "v i " is the direction vector of the tip side joint. The subscript "i" is the index. Therefore, for example, "u1" is the direction vector of the first base side joint 11. "w2" is the direction vector of the second intermediate joint 23. "v3" is the direction vector of the third tip side joint 36. Also, "u i ", "w i ", and "v i " are unit vectors respectively.

[0057] "n" is the direction vector of the tool 110. "α 1i " is the angle formed by "u i " and "w i ". "α 2i " is the angle formed by "w i " and "v i ". "β i " is the angle formed by "Z0" and "v i ". "γ i " is the angle formed by "Z0" and "u i ". "η i"θ" is the mounting phase between adjacent linkages. In other words, it is the angle between "u1 (first base joint 11)" and "u2 (second base joint 21)". Alternatively, it is the angle between "v1 (first tip joint 16)" and "v2 (second tip joint 26)". i " is "u i This is the angle of rotation around the '.

[0058] The above "α 1i " and "α 2i " and "β i " and "γ i Each of the following is the target of the variable filtering in this embodiment. 1i This is referred to as the first angle. 2i This is referred to as the second angle. i This is referred to as the third angle. i This is referred to as the fourth angle.

[0059] Next, we will explain the conditions for the parallel link mechanism to function. Figure 9 is a diagram illustrating the attitude transformation matrix of the tool. As shown in Figure 9, in the case of the initial attitude of the parallel link mechanism ((ψ,θ,Φ)=(0,0,0)), the tool 110 faces the first direction H1. Therefore, the direction vector of the tool 110 is n0=(0,0,1). If we let Q(ψ,θ,Φ) be the attitude transformation matrix when the parallel link mechanism undergoes an attitude transformation, then the tool 110 after the attitude transformation can be expressed as n=Q(ψ,θ,Φ)n0.

[0060] Furthermore, in the case of the initial position of the parallel link mechanism (ψ,θ,Φ)=(0,0,0), the direction vector v of the tip-side joint i * This is as shown in equation (1) below.

[0061]

number

[0062] If the number of links is N, the direction vector of tool 110 and the direction vector vi of the tip-side joint are as shown in equation (2) below.

[0063]

number

[0064] Furthermore, considering the relationship n=Q(ψ,θ,Φ)n0, equation (2) becomes equation (3) below.

[0065]

number

[0066] Vector u i This is given by the following equation (4): vector w i This is given by the following equation (5). Also, the vector u i , w i The vector w has the inner product relation shown in equation (6) below. i , v i The two have the inner product relationship shown in equation (7) below.

[0067]

number

[0068]

number

[0069]

number

[0070]

number

[0071] From the above, the conditions for the parallel link mechanism 100 to be valid are that equation (6) always holds for all index i (i=1,2,3,···N), and in equation (7), θ i The condition is that there is at least one solution for θ. Equation (7) will be referred to below as the inverse kinematic equation. Also, in equation (7), θ i Whether or not there is at least one solution for θ can be determined by the discriminant. Therefore, in this embodiment, the discriminant of the inverse kinematic equation is used to determine θ i For this, the first angle α has at least one solution. 1i、 2nd angle α 2i , third angle β i、 and the fourth angle γ i We've narrowed it down to that.

[0072] Next, we will explain the constraints that arise in the parallel link mechanism 100 when the rotation center P for attitude change is placed at the tip of the tool 110. When the rotation center P for attitude change is placed at the tip of the tool 110, the constraints shown in equations (8) and (9) below arise.

[0073]

number

[0074]

number

[0075] Equation (8) shows that the tip-side joint is always located in the second direction H2 (towards the fixed base 1) relative to the rotation center P. Equation (9) also shows that the base-side joint is always located in the second direction H2 (towards the fixed base 1) relative to the rotation center P. Equations (8) and (9) give the third angle β i、 and the fourth angle γ i The range of design variables is narrowed.

[0076] Also, the first angle α 1i From the fourth angle γ iTo narrow down the design variables, the following equation (10-2) may be used.

[0077]

number

[0078] Equation (10-1) shows that the intermediate joint of the parallel link mechanism 100 is never above the rotation center P, regardless of its orientation. If equation (10-1) is not satisfied, the intermediate joint will be positioned in the first direction H1 above the tip of the tool 110 and may come into contact with the working environment. Therefore, equation (10-1) is derived from the condition of avoiding such a situation. Furthermore, regarding equation (10-1), from equation (9) (0° < γ i Since it is <90°, it is converted to equation (10-2).

[0079] Next, we will explain the formula used to narrow down the link length. Figure 10 is a schematic diagram illustrating the definitions of the end effector base 50 and fixed base 1 of the parallel link mechanism. As shown in Figure 10, the first angle α 1i From the fourth angle γ i Using the design variables, the horizontal size D of the fixed base 1 fb This can be expressed by the following equation (11-1).

[0080]

number

[0081] Equation (11-2) is a rearrangement of equation (11-1). H is the distance (height) from the rotation center P to the fixed base 1. h is the distance between the fixed base 1 and the end effector base 50. lee is the length of the part of the tool 110 that extends upward from the end effector base 50.

[0082] As shown in Figure 10, the horizontal dimension of the end effector base 50 can be expressed by the following equation (12-1). Note that equation (12-2) is a rearranged version of equation (12-1).

[0083]

number

[0084] Figure 11 is a schematic diagram illustrating the base link of a parallel link mechanism. Figure 12 is a simplified version of Figure 11. The virtual triangle shown in Figures 11 and 12 is the triangle connecting the tip joint, the intermediate joint, and the center of rotation. Based on this triangle, the distance l between the center of rotation and the tip joint is calculated. 1i This can be expressed as equation (13-1) below.

[0085]

number

[0086] Distance l between the center of rotation and the tip joint 2i This can be expressed by the above equation (13-2). Also, the base link is bent at its midpoint. Therefore, the base link has a length L of the first extension 104. 1pi and the length L of the second extension 105 1si The relationship can be expressed by the above equation (13-3). Also, the amount of overhang R of the intermediate joint radially outward from the reference line. 1i This can be expressed as equation (13-4) above.

[0087] Figure 13 is a schematic diagram illustrating the base link of the parallel link mechanism. Figure 14 is a simplified version of Figure 13. Figure 15 is a diagram illustrating the overhang of the tip link. As shown in Figures 13 to 15, the length L of the tip link 2i This is given by the following equation (14-1). Also, the distance l from the rotation center p to the tip joint is... 3i This is given by the following equation (14-2).

[0088]

number

[0089] The trigonometric functions of the triangle formed by the rotation center P, the intersection point of the fixed base and the reference line, and the tip-side joint are given by the following equation (15-1).

[0090]

number

[0091] Equation (15-2) is calculated from the sum of the interior angles of the triangle formed by the rotation center P, the intersection point of the fixed base and the reference line, and the tip-side joint. Additionally, the amount R of overhang of the base-side link extending radially outward from the reference line is also calculated. 2i This can be expressed by the following equation (15-3): R - the amount of overhang of the tip-side joint. 2i When calculating this, equations (15-1) and (15-3) are substituted into equation (15-3).

[0092] Figure 16 is a schematic diagram illustrating the dimensions of a parallel link mechanism. As shown in Figure 16, there may be dimensional constraints on the parallel link mechanism. These dimensions are required regardless of the tool's orientation, not just its initial orientation. Furthermore, in the following, regarding the required dimensions, the maximum length in the direction of the reference axis X is used, and the maximum height H is used. MAX In this context, the maximum size of the circular (horizontal) area centered on the reference axis is referred to as the maximum outer diameter. In this case, the diameter D of the end effector base 50 is... eb It must satisfy the following equation (16-1).

[0093]

number

[0094] Also, the diameter D of the fixed base 1 fbneeds to satisfy the above formula (16-2). The overhang amount R of the intermediate joint 1i needs to satisfy the above formula (16-3). The overhang amount R of the tip-side joint 2i needs to satisfy the above formula (16-4). And in this embodiment, the first angle α is obtained using formulas (16-1) to (16-4) 1i、 The second angle α 2i The third angle β i、 And the fourth angle γ i are narrowed down to

[0095] The design support device for the parallel link mechanism is a device that narrows down the design variables of the elements constituting the parallel link mechanism. The elements that can be narrowed down in this embodiment are the first angle α 1i to the fourth angle γ i and the length L of the first extension portion 104 of the base-side link 1pi (hereinafter referred to as the first extension length L 1pi ).

[0096] The design support device narrows down each of the first angle α 1i、 The second angle α 2i The third angle β i、 And the fourth angle γ i as a set. In other words, the design support device does not narrow down the design variable of the first angle α, for example, by ignoring the relationship between the second angle α 2i and the third angle β i and the fourth angle γ i . Therefore, the design support device prepares a plurality of combined angles (α 1i α 1i β 2i γ i γ i ) each including the first angle α 1i, α 2i, β i, γ i ). Then, valid design variables are selected from the plurality of combined angles (α 1i, α 2i, β i, γ i ). Hereinafter, for simplicity, the combined angle (α1i, α 2i, β i, γ i ), among which (α 1i, α 2i, β i, γ i ) may not be denoted.

[0097] Also, the length L of the first extending part 1pi corresponds to each of a plurality of combined angles, and the design variables are narrowed down. In other words, for each combined angle, the design variable of the length L of the first extending part 1pi is narrowed down. Therefore, the length L of the first extending part 1pi is associated with the combined angle.

[0098] Note that when the length L of the first extending part 1pi is narrowed down, by substituting the length L of the first extending part 1pi and the first angle α of the combined angle associated with the length L of the first extending part 1pi into Equation (13-3), the design variable of the length L of the second extending part 105 is indirectly narrowed down. 1i 1si

[0099] Also, when the length L of the first extending part 1pi is narrowed down, by substituting the length L of the first extending part 1pi and the second angle α of the combined angle associated with the length L of the first extending part 1pi and the length lee of the tool 110 into Equation (14-2), the design variable of the length L of the tip-side link is indirectly narrowed down. 2i 2i

[0100] ​​​​Figure 17 shows the flow of the narrowing process in the design support device. When the design support device receives information about the range of motion of the attitude angle of the tool 110, it stores this information about the range of motion of the attitude angle of the tool 110. Then, as shown in Figure 17, the design support device performs a narrowing process based on the stored range of motion of the attitude angle of the tool 110 (start). First, as part of the narrowing process, the combination angles are narrowed down using the discriminant of the inverse kinematics equation (see equation (7)) (S1). Next, it is determined whether the device has stored the dimensional conditions required for the parallel link mechanism 100 in addition to the range of motion of the attitude angle of the tool 110 (S4).

[0101] In step S4, if it is determined that the dimensional conditions required for the parallel link mechanism 100 have been stored, the combination angle and the first extended portion length L are determined using the dimensional conditions required for the parallel link mechanism 100. 1pi The selection is narrowed down (S5). The combination angle and the first extension length L are determined using the dimensional conditions required for the parallel link mechanism 100. 1pi If the narrowing down process is complete, the narrowing down process is terminated (end). Also, if it is determined in step S4 that the dimensional conditions required for the parallel link mechanism 100 are not stored, the narrowing down process is terminated (end).

[0102] After the narrowing down process is complete, the remaining (narrowed down) combination angles (α) 1i, α 2i, β i, γ i ) is presented as an effective design variable. Also, if it is determined in step S4 that the dimensional conditions required for the parallel link mechanism have been stored, the effective first extension length L corresponding to the combination angle is presented. 1pi These are presented as valid design variables. Next, the details of each process will be explained.

[0103] Figure 18 shows the flow of the process of narrowing down combination angles using a discriminant. As shown in Figure 18, the narrowing down of combination angles using the discriminant of the inverse kinematic equation (S1) first involves narrowing down the combination angles using the initial attitude angle of tool 110 as step S10. Then, as step S30, the narrowing down of combination angles is performed using the range of motion of the attitude angle of tool 110.

[0104] Figure 19 shows the flow of narrowing down the combination angle using the initial orientation angle of the tool. Each step included in step S10 will be described. As shown in Figure 19, in step S10, the combination angle (α) is first narrowed down. 1i, α 2i, β i, γ i Prepare the following.

[0105] Specifically, first, one third angle is selected from a predetermined set of angles (S11). Next, one second angle is selected from the predetermined set of angles (S12). Next, one first angle is selected from the predetermined set of angles (S13). Next, one fourth angle is selected from the predetermined set of angles (S14). This prepares combinations of angles in which the first, second, third, and fourth angles have been selected. In this embodiment, the angles are selected in the order of third, second, first, and fourth angles, but this disclosure is not limited to this selection order.

[0106] Here, the predetermined angles described above are angles that can be selected as the first, second, third, and fourth angles (settable angles), and are stored in the design support device. Furthermore, the predetermined angles stored in the design support device have initial values ​​that are set in advance and can be changed by an input device (not shown). To explain in more detail, in this embodiment, the initial value of the predetermined angle stored in the design support device is 0° or more and less than 180°. The design support device then changes and stores the predetermined angle when information (numerical values) that would change the predetermined angle is input. Here, the case in which the predetermined angle is changed is, for example, in this embodiment, when the rotation center P of the parallel link mechanism 100 is located at the tip of the tool 110, and equations (8) and (9) hold true. In other words, the predetermined angle of the third angle is limited to between 90° and less than 180°. Also, the predetermined angle of the fourth angle is limited to between 0° and less than 90°. Therefore, in this embodiment, this information (numerical value) is input by the user to the input device, and the predetermined range of the third and fourth angles stored by the design support device is narrowed. As a result, the predetermined angle of the third angle defined in step S11 is narrowed to less than 180° from 90°. Also, the predetermined angle of the fourth angle defined in step S14 is narrowed to less than 90° from 0°. This reduces the total number of combinations prepared in steps S11 to S14. Note that this disclosure does not limit the initial value of the predetermined angle stored by the design support device to the range of 0° or more and less than 180°. Also, the design support device does not need to store an initial value in advance. In such cases, the design support device stores the angle input by the input device as the predetermined angle.

[0107] Furthermore, in steps S11 to S14, when selecting from a predetermined set of angles, the angles are selected in order from smallest to largest. After step S14 is completed, in step S15, a first-stage narrowing-down determination is performed using the prepared combination of angles.

[0108] Figure 20 shows the flow of the first-stage filtering decision. As shown in Figure 20, the first-stage filtering decision (start of first-stage filtering decision) first selects one link mechanism from multiple link mechanisms (S21). In other words, step S21 selects the index i of the link mechanism. In this embodiment, the total number of link mechanisms is 3. Therefore, the range of index i is 1 ≤ i ≤ 3. Also, in step S15 of this embodiment, index i is selected in the order of 1, 2, and 3.

[0109] Step S22 is the mounting phase η of the link mechanism corresponding to the index i selected in step S21. i (See Figure 8) is calculated. In this embodiment, three link mechanisms are arranged at 120° intervals. Therefore, when the selected index i is 1, the mounting phase η1 of the first link mechanism is 0°. When the selected index i is 2, the mounting phase η2 of the first link mechanism is 120°. When the selected index i is 3, the mounting phase η1 of the third link mechanism is -120°.

[0110] Step S23 involves determining the initial attitude angle of tool 110 (when (ψ,θ,Φ)=(0,0,0)) and the assembly angle (α) prepared in steps S11 to S14. 1i, α 2i, β i, γ i ) and the mounting phase η calculated in step S22 i Substitute this into the first inverse kinematic equation (see equation (7)). Also, in step S23, set up the first discriminant D1 of the first inverse kinematic equation.

[0111] In step S24, it is determined whether the first discriminant is greater than or equal to 0. If the first discriminant is greater than or equal to 0, the first inverse kinematic equation is θ i There is one or more solutions for this, and a parallel link mechanism is established. Therefore, if the first discriminant is determined to be 0 or greater, the combination angle substituted into the first inverse kinematic equation is a valid design variable and is recognized as the first combination angle. Then, proceed to step S25.

[0112] In step S24, if the first discriminant is determined to be less than 0, the first inverse kinematic equation is θ i No solution exists for this. In other words, the substituted combination angle is not a valid design variable. Therefore, the first narrowing-down determination is completed. After that, the process proceeds to step S16 (see Figure 19), where other combination angles are prepared.

[0113] Step S25 involves substituting the first combination angle into equation (10-2). Equation (10-2) is a conditional equation that states that no matter what orientation the parallel link mechanism 100 is in, the intermediate joint is never above the rotation center P. Then, in step S25, it is determined whether equation (10-2) is satisfied.

[0114] If it is determined that equation (10-2) is true, the substituted first combination angle satisfies the requirements for the parallel link mechanism. Therefore, the first combination angle is treated as a valid design variable, and the process proceeds to step S27. On the other hand, if it is determined that equation (10-2) is false, the substituted first combination angle does not satisfy the requirements for the parallel link mechanism. Therefore, the process proceeds to step S18, and other combination angles are prepared. Thus, according to step S25, the number of combination angles with valid design variables (first combination angles) can be reduced.

[0115] Step S26 calculates the first Jacobian matrix J of the first combination angles for the initial position of tool 110 (when (ψ,θ,Φ)=(0,0,0)). Next, it calculates the first Jacobian det(J) of the first Jacobian matrix J. After calculation, proceed to step S27.

[0116] Step S27 determines whether i=3. In step S15 of this embodiment, the index i is selected in the order of 1, 2, and 3. If i=3, the link mechanism associated with the first combination angle is the last link mechanism. In other words, it is recognized that the first combination angle forms a parallel link mechanism in relation to all link mechanisms. Therefore, the process proceeds to the next step S28.

[0117] On the other hand, if it is determined that i is not 3, the process returns to step S21. Then, the link mechanism associated with the combination angle is changed to a different link mechanism (changing the value of index i), and the process undergoes determination S24 again using the first discriminant D1.

[0118] In step S28, the first combination angle is stored. Also, the Jacobian det(J) calculated in step S27 is stored in association with the first combination angle. The number of links (link mechanisms) is also stored. The number of links (link mechanisms) is set to a predetermined range (for example, 4 link mechanisms) and indicates the conditions under which the stored first combination angles were narrowed down. Once stored, the determination of the combination angles (first combination angles) prepared in steps S11 to S14 is completed (end of first narrowing determination S10). Then, the process proceeds to step S16.

[0119] As shown in Figure 19, step S16 is the fourth angle γ included in the combination angle. i Determine if it is the maximum angle within a predetermined range (0° to less than 90°). The fourth angle γ is included in the combination angle. i If it is determined that the angle is not the maximum angle within a predetermined range (0° to less than 90°), the process returns to step S14. Then, in step S14, the fourth angle γ included in the combination angle is determined. i Select an angle one size larger than the given angle and proceed to step S15. This gives the combination of angles provided for the first narrowing-down determination (S17) the fourth angle γ iOnly the other combination angles are changed. On the other hand, the fourth angle γ included in the combination angles i If it is determined that this is the maximum angle within a predetermined range (0° to less than 90°), proceed to step S17.

[0120] Step S17 is the first angle α included in the combination angle. 1i Determine if it is the maximum angle within a predetermined range (0° to less than 180°). The first angle α included in the combination angle. 1i If it is determined that the first angle α included in the combination angle is not the maximum angle within the predetermined angle range (0° to less than 180°), the process returns to step S13. Then, in step S13, the first angle α included in the combination angle is determined. 1i A larger angle is selected for this, and a new combination angle is prepared. Meanwhile, the first angle α included in the combination angle 1i If it is determined that this is the maximum angle within a predetermined range (0° to less than 180°), proceed to step S18.

[0121] Step S18 is the second angle α included in the combination angle. 2i Determine if it is the maximum angle within a predetermined range (0° to less than 180°). The second angle α included in the combination angle. 2i If it is determined that the second angle α included in the combination angle is not the maximum angle within the predetermined range (0° to less than 180°), the process returns to step S12. Then, in step S12, the second angle α included in the combination angle is determined. 2i A larger angle is selected for this, and a new combination angle is prepared. Meanwhile, the second angle α included in the combination angle 2i If it is determined that this is the maximum angle within a predetermined range (0° to less than 180°), proceed to step S19.

[0122] Step S19 is the third angle β included in the combination angle. i It is determined whether it is the maximum angle within a predetermined range (90° to less than 180°). In step S19, the third angle β included in the combination angle is determined. iIf it is determined that the angle is not the maximum angle within the predetermined range (90° to less than 180°), the process returns to step S13. Then, in step S11, the third angle β included in the combined angle is determined. i A larger angle is selected for this, and a new combination of angles is prepared.

[0123] On the other hand, in step S19, the third angle β included in the combination angle i If it is determined that this is the maximum angle within a predetermined range (90° to less than 180°), then the first angle α included in the predetermined range 1i、 2nd angle α 2i , third angle β i、 and the fourth angle γ i All combinations in the sequence have been judged by the first-order discriminant D1, and step S10 ends (end of first-order narrowing judgment S10). Then, the process proceeds to step S30.

[0124] Figure 21 is a diagram showing the flow of narrowing down the combination angles using the range of motion of the tool's posture angle. Next, each step included in step S30 will be described. In step S30, as shown in Figure 21, the number of first-order combination angles that have been stored first is identified. Then, a number is assigned to each first-order combination angle. In this embodiment, the number of first-order combination angles is "k".

[0125] In step S32, one primary combination angle is selected from multiple primary combination angles to be subject to secondary narrowing-down determination. In this embodiment, the primary combination angles are selected in order from the smallest number assigned to them.

[0126] Steps S33 to S35 select one posture angle (ψ, θ, Φ) for tool 110 from the range of motion of the posture angle of tool 110. Specifically, step S33 selects one posture angle θ from the range of motion of the posture angle of tool 110 in the y component (from θmin to less than θmax). Step S34 selects one posture angle ψ from the range of motion of the posture angle of tool 110 in the x component (from ψmin to less than ψmax). Step S35 selects one posture angle Φ from the range of motion of the posture angle of tool 110 in the z component (from Φmin to less than Φmax). After step S35 is completed, the second narrowing-down determination (S36) is performed.

[0127] Furthermore, in steps S33 to S35, the angles to be selected are chosen in order from the smallest angle among the angles included in the range of motion. Hereinafter, the posture angle of the tool 100 prepared in steps S33 to S35 may be referred to as the selected posture angle. In this embodiment, the y component, x component, and z component are selected in that order, but this disclosure is not limited to this selection order.

[0128] Figure 22 shows the flow of the second-stage narrowing decision. As shown in Figure 22, the second-stage narrowing decision (start of the second-stage narrowing decision S36) first selects one link mechanism from multiple link mechanisms (S51). Next, the mounting phase η of the link mechanism corresponding to the selected index i is determined. i The result is calculated (S52). Note that steps S51 and S52 are the same process as steps S21 and S22, so a detailed explanation is omitted.

[0129] Step S53 involves the selected attitude angle prepared in steps S33 to S35, the first assembly angle selected in step S32, and the mounting phase η calculated in step S52. i Substitute this into the second inverse kinematic equation (see equation (7)). Also, in step S35, set up the second discriminant D2 of the second inverse kinematic equation.

[0130] In step S54, it is determined whether the second discriminant is greater than or equal to 0. If the second discriminant is greater than or equal to 0, the second inverse kinematic equation is θ i There is one or more solutions for this, and a parallel link mechanism is established. Therefore, if the second discriminant is determined to be 0 or greater, the first combination angle substituted into the second inverse kinematic equation is a valid design variable and is recognized as the second combination angle. Then, the process proceeds to step S55.

[0131] On the other hand, if the second discriminant is determined to be less than 0 in step S54, the second inverse kinematic equation is θ i No solution is found for this. In other words, the substituted first combination angle is not a valid design variable. Therefore, the second refinement check is terminated (end of second refinement check). After the second refinement check is completed, proceed to step S41.

[0132] Step S55 calculates the second Jacobian matrix J of the quadratic combination angle when the tool 110 is set to the selected orientation angle (ψ,θ,Φ). Next, it calculates the second Jacobian det(J) of the second Jacobian matrix J. After calculation, the process proceeds to step S56.

[0133] Step S56 calculates the code function sgn(det(J0)) of the first Jacobian. It also calculates the code function sgn(det(J)) of the second Jacobian. Then, in step S57, it is determined whether the code function sgn(det(J0)) of the first Jacobian and the code function sgn(det(J)) of the second Jacobian are equal.

[0134] If the sign function sgn(det(J0)) of the first Jacobian and the sign function sgn(det(J)) of the second Jacobian are not equal, the first combination angle contains a singularity (uncontrollable posture) within the range of motion of the tool's posture angle. In other words, the second combination angle is not a valid design variable.

[0135] Therefore, if it is determined in step S57 that the sign function sgn(det(J0)) of the first Jacobian and the sign function sgn(det(J)) of the second Jacobian are not equal, the first combination angle is considered an invalid design variable, and the second narrowing-down determination ends (end of the second narrowing-down determination S36). After the end of the second narrowing-down determination, the process proceeds to step S41.

[0136] On the other hand, if it is determined in step S57 that the code function sgn(det(J0)) of the first Jacobian and the code function sgn(det(J)) of the second Jacobian are equal, the process proceeds to step S58.

[0137] In step S58, it is determined whether the index associated with the second combination angle is i=3.

[0138] If it is determined in step S58 that i=3, the process returns to step S51 to determine whether a parallel link mechanism is established in relation to other link mechanisms.

[0139] On the other hand, if it is determined in step S58 that i=3, the link mechanism associated with the second combination angle is the last link mechanism. In other words, the second combination angle is recognized as being in a parallel link mechanism relationship with all link mechanisms in the multiple link mechanisms. Therefore, if it is determined that i=3, the second narrowing-down determination is completed (end of the second narrowing-down determination S36). After the completion of the second narrowing-down determination, the process proceeds to step S37.

[0140] As shown in Figure 21, step S37 determines whether the z component Φ included in the selected posture angle is the maximum angle within the range of motion of the tool 100's posture angle (from Φmin to less than Φmax). If it is determined that the z component Φ included in the selected posture angle is not the maximum angle within the range of motion of the tool 100's posture angle (from Φmin to less than Φmax), the process returns to step S35. Then, in step S35, an angle one size larger than the z component Φ included in the selected posture angle is selected, and the process proceeds to step S36. On the other hand, if it is determined that the z component Φ included in the selected posture angle is the maximum angle within the range of motion of the tool 100's posture angle (from Φmin to less than Φmax), the process proceeds to step S38.

[0141] Step S38 determines whether the x-component ψ included in the selected posture angle is the maximum angle within the range of motion of the posture angle of tool 100 (from ψmin to less than ψmax). If it is determined that the x-component ψ included in the selected posture angle is not the maximum angle within the range of motion of the posture angle of tool 100 (from ψmin to less than ψmax), the process returns to step S34. Then, in step S34, an angle one size larger than the x-component ψ included in the selected posture angle is selected, and the process proceeds to step S35. On the other hand, if it is determined that the x-component ψ included in the selected posture angle is the maximum angle within the range of motion of the posture angle of tool 100 (from ψmin to less than ψmax), the process proceeds to step S39.

[0142] Step S39 determines whether the y-component θ included in the selected posture angle is the maximum angle within the range of motion of the posture angle of tool 100 (from θmin to less than θmax). If it is determined that the y-component θ included in the selected posture angle is not the maximum angle within the range of motion of the posture angle of tool 100 (from θmin to less than θmax), the process returns to step S33. Then, in step S33, an angle one size larger than the y-component θ included in the selected posture angle is selected, and the process proceeds to step S34. On the other hand, if it is determined that the y-component θ included in the selected posture angle is the maximum angle within the range of motion of the posture angle of tool 100 (from θmin to less than θmax), the process proceeds to step S40.

[0143] According to steps S37 to S39 above, for each second combination angle, only the second combination angles in which the parallel link mechanism 100 is determined to be established within the range of motion of the tool 110's posture angle proceed to step S40. Then, in step S40, the total number of second combination angles and link mechanisms is stored. After that, the process proceeds to step S41.

[0144] In step S41, it is determined whether the number assigned to the second combination angle (first combination angle) is "k". In other words, if it is determined that the number assigned to the second combination angle is "k", then all of the first combination angles have undergone the second narrowing-down determination (S36), and step S30 ends. Then, the process proceeds to step S4. On the other hand, if it is determined that the number assigned to the second combination angle is not "k", the process returns to step S32 and performs the second narrowing-down determination (S36) on the other first combination angles.

[0145] As shown in Figure 17, step S4 determines whether the dimensional conditions required for the parallel link mechanism 100 are stored. Note that if these dimensional conditions for the parallel link mechanism 100 are input to the input device, the design support device stores them. Here, the dimensional conditions required for the parallel link mechanism 100 refer to the maximum outer diameter D of the parallel link mechanism. MAX (See Figure 16) and the maximum height H of the parallel link mechanism. MAX (See Figure 16) and the length l of tool 110 ee (See Figure 10.)

[0146] Furthermore, in step S4, the maximum outer diameter D MAX and maximum height H MAX and the length of tool 110 l ee It determines whether all of the above are remembered. Then, it determines the maximum outer diameter D. MAX and maximum height H MAX and the length of tool 110 l ee If it is determined that not all of the above is remembered, the process proceeds to the end and terminates. Meanwhile, the maximum outer diameter D MAXand maximum height H MAX and the length of tool 110 l ee If it is determined that you remember all of it, proceed to step 7.

[0147] Figure 23 shows the refinement flow using the required dimensional conditions. Each step included in step S7 is described below. As shown in Figure 23, in step S7, the number of second combination angles that were initially stored is identified (S71). Then, a number is assigned to each second combination angle. In this embodiment, the number of second combination angles is "kk".

[0148] In step S72, one second combination angle is selected from a plurality of second combination angles. In this embodiment, the second combination angles are selected in order from the smallest number assigned to them.

[0149] Step S73 is the size D of the end effector base 50. eb The calculation method is as follows: Equation (12-2) is used, and the third angle β included in the selected second combination angle is used. i The length of the tool to remember l ee Substitute the value. Then, step S74 calculates the size D of the end effector base. eb However, the maximum outer diameter D of the parallel link mechanism 100 to be stored is... MAX The following is determined. The conditional expression for step S74 is expression (16-1). Hereinafter, the determination in step S74 will be referred to as the third-level refinement determination.

[0150] In step S74, the size D of the calculated end effector base 50 is... eb However, the maximum outer diameter D of the parallel link mechanism 100 MAX If it is determined that the value exceeds the limit, the selected secondary combination angle does not meet the dimensional requirements. Therefore, proceed to step S78.

[0151] On the other hand, in step S74, the size D of the calculated end effector base 50 is ebHowever, the maximum outer diameter D of the parallel link 100 mechanism MAX If the following is determined, the second combination angle is recognized as a third combination angle that satisfies the dimensional requirements, and the process proceeds to step S75.

[0152] In step S75, the size of the fixed base D fb The calculation method involves adding the fourth angle γ included in the selected third combination angle to equation (11-2). i Substitute the following. Also, replace "H" in equation (11-2) with the maximum height H of the parallel link mechanism. MAX Substitute this value.

[0153] Then, in step S76, the size D of the fixed base 1 is calculated. fb However, the maximum outer diameter D of the parallel link mechanism 100 to be stored is... MAX The following is determined. The conditional expression for step S74 is expression (16-2). Hereafter, the determination in step S76 will be referred to as the fourth-stage narrowing determination.

[0154] In step S76, the size D of the fixed base 1 was calculated. fb The maximum outer diameter D of the parallel link mechanism 100 that is stored in memory. MAX If it is determined that the value exceeds the limit, the third combination angle does not meet the dimensional requirements. Therefore, proceed to step S78.

[0155] Meanwhile, in step S76, the size D of the fixed base 1 fb The maximum outer diameter D of the parallel link mechanism 100 that is stored in memory. MAX If the following is determined, the third combination angle is recognized as the fourth combination angle that satisfies the dimensional requirements, and the process proceeds to step S77 to perform the first extension length narrowing determination.

[0156] Figure 24 shows the flow of the first narrowing-down determination. As shown in Figure 24, step S77 is the first extension length L from the dimensional requirements. 1pi This is the process of narrowing down the first extension length L in the first step S81. 1piFrom a predetermined length, the first extended portion length L 1pi Select the length. Note that the predetermined length is the length of the first extended portion L. 1pi This is the range that can be set. Furthermore, the design support device will use the smallest value within the settable range, L. 1pi_MIN And the largest value is L 1pi_MAX It stores L. 1pi_MIN and L 1pi_MAX This is information entered by the user. Then, in step S81, a predetermined length (L 1pi_MIN That's all, L 1pi_MAX Select the smallest value from the following. In this embodiment, the design support device stores the value entered by the user as a predetermined length, but the design support device may also store a pre-set initial value.

[0157] Step S82 involves selecting one link mechanism from among several link mechanisms.

[0158] Step S83 involves determining the fourth combination angle and the selected first extension length L. 1pi From the first overhang R 1i The first overhang amount R is calculated. 1i To calculate this, use equations (13-1) through (13-4) with the fourth combination angle and the selected first extension length L. 1pi Substitute this value.

[0159] Step S84 is the first overhang amount R 1i The maximum outer diameter D of the parallel link mechanism 100 MAX The maximum radius of half of (D MAX Determine if it is less than ( / 2). The conditional expression for this step S84 is expression (16-3). Hereafter, the determination in step S84 will be referred to as the fifth-order refinement determination.

[0160] In step S84, the first overhang amount R 1i The maximum radius (D) of the parallel link mechanism 100 MAX If it is determined to be 2) or more, the first extended portion length L selected in step S81 1piIt does not meet the dimensional requirements. Therefore, proceed to step S89.

[0161] Meanwhile, in step S84, the first protrusion amount R 1i The maximum radius (D) of the parallel link mechanism 100 MAX If it is determined to be smaller than / 2), the first extended portion length L 1pi The first extended portion length L that satisfies the dimensional requirements. 1pi This is confirmed, and we proceed to step S85.

[0162] Step S85 involves the fourth combination angle and the first progressive extension length L. 1pi From the second overhang R 2i The second overhang amount R is calculated. 2i To calculate this, use equations (14-1) through (15-3) with the fourth combination angle and the selected first extension length L. 1pi Substitute this value.

[0163] Step S86 is the second overhang R 2i The maximum radius (D) is half of the maximum outer diameter Dmax of the parallel link mechanism 100. MAX Determine if it is less than ( / 2). The conditional expression for this step S86 is expression (16-4). Hereafter, the determination in step S86 will be referred to as the sixth-order refinement determination.

[0164] In step S86, the second overhang amount R 2i The maximum radius (D) of the parallel link mechanism MAX If it is determined to be 2) or more, the first extended portion length L selected in step S81 1pi It does not meet the dimensional requirements. Therefore, proceed to step S89.

[0165] On the other hand, in step S86, the second protrusion amount R 2i The maximum radius (D) of the parallel link mechanism MAX If it is determined to be smaller than / 2, the first stage extension length L 1pi The second stage 1 extending part length L that meets the dimensional requirements. 1pi This is confirmed, and we proceed to step S87.

[0166] In step S87, it is determined whether the index associated with the second first extension length L 1pi is i = 3. If it is determined that i = 3, the link mechanism associated with the second first extension length L 1pi is the last link mechanism. Therefore, the second first extension length L 1pi is recognized to satisfy the dimensional requirements in relation to all link mechanisms in the plurality of link mechanisms. Therefore, proceed to the next step S88.

[0167] Step S88 stores the fourth combination angle and the second first extension length L 1pi . Here, the second first extension length L 1pi is a value that satisfies the dimensional requirements in the fifth narrowing and the sixth narrowing determination under the condition of the fourth combination angle. Therefore, the second first extension length L 1pi is stored in the state associated with the fourth combination angle. Also, the total number of link mechanisms is stored together.

[0168] Step S89 determines whether the second first extension length L 1pi is equal to L 1pi_MAX . L 1p_MAX is the maximum length within the range where the first extension length L 1pi can be selected. Therefore, if it is determined that the second first extension length L 1pi is smaller than L 1pi_MAX , return to step S81, change the value of the second first extension length L 1pi to a larger length, and perform the fifth narrowing determination and the sixth narrowing determination again.

[0169] On the other hand, if it is determined that the second first extension length L 1pi is equal to L 1pi_MAX , for one fourth combination angle, all lengths included in a predetermined length are determined, and proceed to step S90.

[0170] In step S78, it is determined whether the number assigned to the fourth combination angle (second combination angle) is "kk". If it is determined that the number assigned to the fourth combination angle is not "kk", the process returns to step S72, and the third narrowing-down determination S74 is performed for other second combination angles.

[0171] On the other hand, if in step S78 it is determined that the number assigned to the fourth combination angle is "kk", all of the second combination angles have undergone the third narrowing-down determination (S74), the fourth narrowing-down determination (S76), the fifth narrowing-down determination (S84), and the sixth narrowing-down determination (S86), and the process of step S7 ends. As a result, the narrowing-down operation by the design support device ends (ends).

[0172] As described above, according to the design support device, when the process ends through step S7, in the storage unit, a plurality of fourth combination angles (α 1i, α 2i, β i, γ i ) are stored. Also, in a state associated with the fourth combination angle, the second first extension length L 1pi is stored. Also, the total number of determined link mechanisms is stored. Therefore, for the first angle α 1i、 the second angle α 2i , the third angle β i、 and the fourth angle γ i , they are narrowed down from a predetermined angle (refer to S11 to S14) to valid design variables. Also, for the second first extension length L 1pi , it is narrowed down from a predetermined length (refer to S81) to a value that satisfies the dimensional requirements. Therefore, the burden on the designer is reduced.

[0173] Also, if the process ends directly from step S4, in the storage unit, a plurality of second combination angles (α 1i, α 2i, β i, γ i ) are stored. Even in this case, they are narrowed down from a predetermined angle (refer to S11 to S14) to valid design variables, and the burden on the designer is reduced.

[0174] While embodiments have been described above, this disclosure is not limited thereto. For example, the design support device may perform only step S1 and not step S4 and step S7. Even performing only step S1 reduces the number of combination angles and lessens the burden on the designer. Also, the rotation center P for the attitude change of the parallel link mechanism 100 may be on the center line of the tool 110 and may not be at the tip of the tool 110. In this case, equations (8), (9), (10-1), and (10-2) do not hold. In this case, the predetermined angles set in steps S11 and S14 will be between 0° and less than 180°. Also, step S25 becomes unnecessary. Furthermore, although a determination of the presence or absence of a singularity (step S57) is performed, this disclosure does not require it. In this case, steps S26, S55, and S56 also become unnecessary.

[0175] Furthermore, this disclosure may also be a combination of the following configurations. (1) A design support device for a parallel link mechanism that performs attitude changes around a rotation center on the centerline of the tool, which narrows down the design variables that satisfy the required range of motion for the attitude angle of the tool, The aforementioned parallel link mechanism is Fixed base and An end effector base supporting the aforementioned tool, Multiple link mechanisms connecting the fixed base and the end effector base, Equipped with, The aforementioned link mechanism is A base-side joint that is rotatably connected to the aforementioned fixed base, A base-side link, one end of which is connected to the base-side joint, An intermediate joint provided at the other end of the base-side link, A tip-side link whose one end is rotatably connected to the base-side link via the aforementioned intermediate joint, A tip-side joint that rotatably connects the other end of the aforementioned tip-side link to the end effector base, It has, The design variables that are narrowed down are: The first angle formed by the base joint and the intermediate joint, The second angle formed by the intermediate joint and the tip joint, The third angle formed by the reference line, which is a perpendicular line drawn from the center of rotation to the fixed base, and the intermediate joint, The fourth angle formed by the aforementioned reference line and the aforementioned tip-side joint, And, The range of motion of the required posture angle of the tool, Each of the first angle, second angle, third angle, and fourth angle is a predetermined angle that can be set, Remember this, A combination of angles including the first angle, second angle, third angle, and fourth angle selected from the predetermined angles, wherein a plurality of such combinations are prepared in which at least one of the first angle, second angle, third angle, and fourth angle is different. Select one of the prepared combination angles, Substitute the selected combination angle and the initial angle of the tool into the first inverse kinematic equation, A first-order narrowing-down determination is performed to determine whether the requirements for the establishment of the parallel link mechanism are met by using the discriminant of the first-order inverse kinematic equation. The combination angle that is determined to satisfy the aforementioned requirements is designated as the first combination angle. After the first narrowing-down determination, the process of selecting another combination angle from the multiple combination angles and performing the first narrowing-down determination is repeated, thereby narrowing down the multiple combination angles to a multiple first combination angles. Select one of the aforementioned primary combination angles from a plurality of aforementioned primary combination angles, Select a selected posture angle from the range of motion of the aforementioned tool, Substitute the selected first combination angle and the selected attitude angle into the second inverse kinematic equation, A second-order narrowing-down determination is performed to determine whether the requirements for the establishment of the parallel link mechanism are met by using the discriminant of the second-order inverse kinematic equation. After the second narrowing-down determination, the selected first combination angle is kept as is, and another selected posture angle is selected from the range of motion of the tool's posture angle, and the second narrowing-down determination is repeated. The first combination angle that is determined to satisfy the requirements for all posture angles of the tool within the range of motion of the tool's posture angle is designated as the second combination angle. Once the secondary narrowing-down determination for one of the selected primary combination angles is completed, the process is repeated by selecting another primary combination angle from the multiple primary combination angles and performing the secondary narrowing-down determination again, thereby narrowing down the multiple primary combination angles to secondary combination angles. A design support device for parallel link mechanisms. (2) The tool calculates the first Jacobian of the first combination angle when it is in its initial position. The tool calculates the second Jacobian of the second combination angle for the selected posture angle, The sign function of the first Jacobian and the sign function of the second Jacobian are calculated, We perform a singularity test to determine if the sign function of the second Jacobian is equal to the sign function of the second Jacobian. The first combination angle that was determined to be unequal will not be designated as the second combination angle. (2) A design support device for the parallel link mechanism described above. (3) When the rotation center of the parallel link mechanism is located at the tip of the tool, the range of the third angle included in the combination angle is narrowed to 90° to less than 180°, and the range of the fourth angle is narrowed to 0° to less than 90°. A design support device for the parallel link mechanism described in (1) or (2). (4) When the intermediate joint does not move to the opposite side of the fixed base from the rotation center regardless of the posture of the parallel link mechanism, it is determined whether the Z component of the intermediate joint with the combined angle substituted is closer to the fixed base than the rotation center. The combined angle determined not to have the Z component of the intermediate joint closer to the fixed base than the rotation center is not recognized as the first combined angle. The design support device for a parallel link mechanism according to any one of (1) to (3). (5) Store the maximum outer diameter value of the parallel link mechanism, the maximum height value of the parallel link mechanism, and the length of the tool, which are dimensional conditions. Select one of the plurality of second combined angles. Based on the third angle included in the selected second combined angle and the length of the tool, calculate the size of the end effector base. Perform a third screening determination as to whether the calculated size of the end effector base is less than or equal to the maximum outer diameter value of the parallel link mechanism. Recognize the second combined angle determined to be less than or equal to the maximum outer diameter value of the parallel link mechanism as the third combined angle. Based on the fourth angle included in the third combined angle, calculate the size of the fixed base. Perform a fourth screening determination as to whether the calculated size of the fixed base is less than or equal to the required maximum outer diameter value of the parallel link mechanism. Recognize the third combined angle determined to have the calculated size of the fixed base less than or equal to the maximum outer diameter value of the parallel link mechanism as the fourth combined angle. When it is determined in the third screening determination that the maximum outer diameter value of the parallel link mechanism is exceeded and when the fourth screening determination is completed, repeatedly select another second combined angle from the plurality of second combined angles and perform the third screening determination to narrow down from the plurality of second combined angles to the fourth combined angle. A design support device for a parallel link mechanism as described in any one of (1) to (4). (6) The design variable that is narrowed down is the length of the first extended portion of the base-side link, from the middle portion of the base-side link to the portion that connects to the base-side joint. The length of the first extension is set to a predetermined length and stored in memory. One of the predetermined lengths is selected as the length of the first extended portion. Select one of the aforementioned fourth combination angles from a plurality of aforementioned fourth combination angles, Based on the selected fourth combination angle and the selected first extension length, the first overhang amount of the intermediate joint extending radially outward is calculated. The fifth-order narrowdown determination is made to determine whether the first overhang amount is less than the maximum radius of half the maximum outer diameter. The length of the first extended portion determined to be less than half the maximum radius of the maximum outer diameter is determined to be the first extended portion length. Based on the length of the first extension and the fourth combination angle, the second overhang amount at which the tip-side joint protrudes most radially outward is calculated. The sixth-order filtering determination is performed to determine whether the second overhang amount is less than the maximum radius. The length of the first extended portion that is determined to be less than the maximum radius is determined to be the length of the second extended portion. If the fifth narrowing determination determines that the first overhang is greater than or equal to half the maximum radius of the maximum outer diameter, and if the sixth narrowing determination is successful, the fourth combination angle is kept the same, the first extension length is changed to another length, and the fifth narrowing determination and the sixth narrowing determination are repeated, thereby narrowing the first extension length corresponding to the fourth combination angle from the predetermined length to the second first extension length. When the length of the first extension corresponding to one of the aforementioned fourth combination angles has been narrowed, another aforementioned fourth combination angle is selected from the plurality of aforementioned fourth combination angles, and the length of the second progressive extension corresponding to the selected other aforementioned fourth combination angle is narrowed. (5) A design support device for the parallel link mechanism described above. [Explanation of symbols]

[0176] 1 Fixed base 2 axes 3 Link mechanism 6 motors 10. First Link Mechanism 11, 11A First base side joint 12 First cylindrical section 13. First base side link 14. First Intermediate Joint 15. First tip-side link 16. First tip-side joint 20. Second Link Mechanism 21, 21A Second base side joint 22 Second cylindrical section 23. Second base side link 24. Second Intermediate Joint 25. Second tip-side link 26. Second tip joint 30 Third Link Mechanism 31, 31A Third base side joint 32 Third cylindrical section 33. Third base side link 34 Third Intermediate Joint 35. Third tip-side link 36 Third tip joint 50 End Effector Bass 51b Opposite surface 53 Support part 100, 100A Parallel Link Mechanism 101 Base L, M1, M2, M3, N1, N2 extension line P tip Z reference line

Claims

1. A design support device for a parallel link mechanism that performs attitude changes around a rotation center on the centerline of the tool, which narrows down the design variables that satisfy the required range of motion for the attitude angle of the tool, The aforementioned parallel link mechanism is Fixed base and An end effector base supporting the aforementioned tool, Multiple link mechanisms connecting the fixed base and the end effector base, Equipped with, The aforementioned link mechanism is A base-side joint that is rotatably connected to the aforementioned fixed base, A base-side link, one end of which is connected to the base-side joint, An intermediate joint provided at the other end of the base-side link, A tip-side link whose one end is rotatably connected to the base-side link via the aforementioned intermediate joint, A tip-side joint that rotatably connects the other end of the aforementioned tip-side link to the end effector base, It has, The design variables that are narrowed down are: The first angle formed by the base joint and the intermediate joint, The second angle formed by the intermediate joint and the tip joint, The third angle formed by the reference line, which is a perpendicular line drawn from the center of rotation to the fixed base, and the tip-side joint, The fourth angle formed by the aforementioned reference line and the aforementioned base-side joint, And, The range of motion of the required posture angle of the tool, Each of the first angle, the second angle, the third angle, and the fourth angle is a predetermined angle that can be set, Remember this, A combination of angles including the first angle, second angle, third angle, and fourth angle selected from the predetermined angles, wherein a plurality of such combinations are prepared in which at least one of the first angle, second angle, third angle, and fourth angle is different. Select one of the prepared combination angles, Substitute the selected combination angle and the initial angle of the tool into the first inverse kinematic equation, A first-order narrowing-down determination is performed to determine whether the requirements for the establishment of the parallel link mechanism are met by using the discriminant of the first-order inverse kinematic equation. The combination angle that is determined to satisfy the aforementioned requirements is designated as the first combination angle. After the initial narrowing determination, the process of selecting another combination angle from the multiple combination angles and performing the initial narrowing determination is repeated, thereby narrowing down the multiple combination angles to a plurality of the initial combination angles. Select one of the above first combination angles from a plurality of the above first combination angles, Select a selected posture angle from the range of motion of the aforementioned tool, Substitute the selected first combination angle and the selected attitude angle into the second inverse kinematic equation, A second-order narrowing-down determination is performed to determine whether the requirements for the establishment of the parallel link mechanism are met by using the discriminant of the second-order inverse kinematic equation. After the second narrowing-down determination, the selected first combination angle is kept as is, and another selected posture angle is selected from the range of motion of the tool's posture angle, and the second narrowing-down determination is repeated. The first combination angle that is determined to satisfy the requirements for all posture angles of the tool within the range of motion of the tool's posture angle is designated as the second combination angle. Once the secondary narrowing-down determination for one of the selected primary combination angles is completed, the process is repeated by selecting another primary combination angle from the multiple primary combination angles and performing the secondary narrowing-down determination again, thereby narrowing down the multiple primary combination angles to secondary combination angles. A design support device for parallel link mechanisms.

2. The tool calculates the first Jacobian of the first combination angle when it is in its initial position. The tool calculates the second Jacobian of the second combination angle for the selected posture angle, The sign function of the first Jacobian and the sign function of the second Jacobian are calculated, A singularity determination is made to determine whether the sign function of the first Jacobian and the sign function of the second Jacobian are equal. The first combination angle that was determined to be unequal will not be designated as the second combination angle. A design support device for a parallel link mechanism according to claim 1.

3. When the rotation center of the parallel link mechanism is located at the tip of the tool, the range of the third angle included in the combination angle is narrowed to 90° to less than 180°, and the range of the fourth angle is narrowed to 0° to less than 90°. A design support device for a parallel link mechanism according to claim 2.

4. If, regardless of the orientation of the parallel link mechanism, the intermediate joint does not move to the opposite side of the fixed base from the center of rotation, then it is determined whether the Z component of the intermediate joint, with the combined angle substituted, is closer to the fixed base than the center of rotation. The combination angle determined to be not closer to the fixed base than the rotation center is not designated as the first combination angle. A design support device for a parallel link mechanism according to claim 3.

5. The dimensional conditions, namely the maximum outer diameter of the parallel link mechanism, the maximum height of the parallel link mechanism, and the length of the tool, are stored. Select one of the aforementioned secondary combination angles from a plurality of aforementioned secondary combination angles, Based on the third angle included in the selected secondary combination angle and the length of the tool, the size of the end effector base is calculated. A third-order filtering determination is performed to determine whether the calculated size of the end effector base is less than or equal to the maximum outer diameter of the parallel link mechanism. The secondary combination angle, which is determined to be less than or equal to the maximum outer diameter of the parallel link mechanism, is designated as the tertiary combination angle. Based on the fourth angle included in the third combination angle, the size of the fixed base is calculated. A fourth-order refinement determination is performed to determine whether the calculated size of the fixed base is less than or equal to the required maximum outer diameter of the parallel link mechanism. The third combination angle, which is determined to be less than or equal to the maximum outer diameter of the parallel link mechanism, is designated as the fourth combination angle. If the third-order narrowing-down determination determines that the maximum outer diameter of the parallel link mechanism is exceeded, and if the fourth-order narrowing-down determination is completed, the process of selecting another second-order combination angle from the multiple second-order combination angles and performing the third-order narrowing-down determination is repeated, thereby narrowing down the multiple second-order combination angles to the fourth-order combination angle. A design support device for a parallel link mechanism according to any one of claims 1 to 4.

6. The design variable that is narrowed down is the length of the first extended portion of the base-side link, from the middle portion of the base-side link to the portion that connects to the base-side joint. The length of the first extension is set to a predetermined length and stored in memory. One length of the first extended portion is selected from the predetermined length, Select one of the aforementioned fourth combination angles from a plurality of aforementioned fourth combination angles, Based on the selected fourth combination angle and the selected first extension length, the first overhang amount of the intermediate joint extending radially outward is calculated. The fifth-order narrowdown determination is made to determine whether the first overhang amount is less than the maximum radius of half the maximum outer diameter. The length of the first extended portion determined to be less than half the maximum radius of the maximum outer diameter is determined to be the first extended portion length. Based on the length of the first extension and the fourth combination angle, the second overhang amount at which the tip-side joint protrudes most radially outward is calculated. The sixth-order filtering determination is performed to determine whether the second overhang amount is less than the maximum radius. The length of the first extended portion, which is determined to be less than the maximum radius, is recognized as the length of the second extended portion, If the fifth narrowing determination determines that the first overhang amount is greater than or equal to half the maximum radius of the maximum outer diameter, and if the sixth narrowing determination is completed, the fourth combination angle is kept the same, the first extension length is changed to another length, and the fifth narrowing determination is performed, and the sixth narrowing determination is performed repeatedly, thereby narrowing the first extension length corresponding to the fourth combination angle from the predetermined length to the second first extension length. When the length of the first extension corresponding to one of the fourth combination angles has been narrowed, another fourth combination angle is selected from the multiple fourth combination angles, and the length of the second extension corresponding to the selected other fourth combination angle is narrowed. A design support device for a parallel link mechanism according to claim 5.

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