Eight-shaft linkage six-rod parallel radial plastic forming robot

Abstract

The eight-shaft linkage six-rod parallel radial plastic forming robot comprises a left lathe bed and a right lathe bed, a driving shaft is connected with the left lathe bed, and the other end of a corresponding connecting rod is matched with a main shaft seat through ball pair constraint; six groups of connecting rods are simultaneously mounted on a spindle seat in parallel, the spindle seat is connected with a left lathe bed through a damping rod, a spindle is mounted on the spindle seat and driven by a main speed reducer and a main motor, a mandrel is mounted on the spindle, the front end of a slider is connected with a main oil cylinder, and the slider and a driving slider of the main oil cylinder can move along the axis of the guide rail under the constraint of the guide rail. A workpiece rotary table is installed in the center of the sliding block and can rotate on the sliding block along the axis, and rotation is driven by a workpiece speed reducer and a workpiece motor which are installed on the sliding block. The method can realize one-time radial integral forming of the complex thin-wall high-rib cylinder part, has the characteristics of simple manufacturing process, low manufacturing cost, high manufacturing strength and the like, and is particularly suitable for integral forming of parts with extremely large length-diameter ratios, high rib-thickness ratios and the like in aerospace.

Description

Eight-axis linkage six-bar parallel radial plastic forming robot Technical Field

[0001] This invention relates to the field of special metal forming equipment, and more specifically, to an eight-axis linkage six-bar parallel radial plastic forming robot. Background Technology

[0002] Thin-walled, highly ribbed cylindrical components are structural parts with highly ribbed inner walls. They possess advantages such as high load-bearing capacity and high structural rigidity, and are widely used in the cabins of aerospace equipment such as rockets, aircraft, and navigation systems. Currently, these structural components can only be manufactured using a split-piece forming method, leading to problems such as complex manufacturing processes, high manufacturing costs, and low manufacturing strength. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an eight-axis linkage six-bar parallel radial plastic forming robot, which can realize the one-time radial integral forming of complex thin-walled high-rib cylindrical parts.

[0004] The technical solution adopted by this invention to solve its technical problem is as follows: An eight-axis linkage six-bar parallel radial plastic forming robot is constructed, including a left bed and a right bed. Six reducers are fixedly mounted on the left bed. The input end of each reducer is connected to a corresponding drive motor via a coupling, and the output end of each reducer is fixedly connected to a corresponding drive shaft. The drive shaft is connected to the left bed and is an eccentric shaft. Its eccentric end is dynamically fitted with a corresponding connecting rod through a ball joint constraint, and the other end of the corresponding connecting rod is also fitted with a spindle seat through a ball joint constraint. The six sets of connecting rods are simultaneously installed in parallel on the spindle seat. The space is fully constrained. The spindle seat is connected to the left bed via a damping rod. The spindle is mounted on the spindle seat and driven by the main reducer and main motor. A mandrel is mounted on the spindle. A slider is mounted on the right bed via four guide rails. The front end of the slider is connected to the main hydraulic cylinder. Under the constraint of the guide rails and driven by the main hydraulic cylinder, the slider can move along the guide rail axis. A workpiece turntable is mounted at the center of the slider. The workpiece turntable can rotate on the slider along its axis. This rotation is driven by a workpiece reducer and workpiece motor mounted on the slider. The workpiece is mounted on the workpiece turntable via a mold and can rotate with the workpiece turntable.

[0005] According to the above scheme, the drive shaft is connected to the left bed via bearings.

[0006] According to the above scheme, the spatial position and attitude of the spindle seat are adjusted by controlling the position of the six drive motors.

[0007] According to the above scheme, the left bed and the right bed are fixedly connected by a square column and the tie rod therein.

[0008] According to the above scheme, both sides of the right bed are equipped with stop blocks. The stop blocks can move along the axis perpendicular to the slider under the drive of the stop block cylinder, so as to fix the slider processing position.

[0009] According to the above scheme, an ejector cylinder is installed at the lower end of the right bed. The ejector cylinder can move up and down under the drive of hydraulic oil to eject the workpiece.

[0010] According to the above scheme, the core mold rotates under the drive of the main motor.

[0011] According to the above scheme, the front end of the slider is connected to the main oil cylinder through the main tie rod.

[0012] The present invention also provides a method for machining thin-walled, high-ribbed cylindrical parts using the aforementioned eight-axis linkage six-bar parallel radial plastic forming robot, comprising the following steps:

[0013] S1. Select multi-degree-of-freedom spatial forming motion based on the geometric switching characteristics of the workpiece, generate motion data for six drive motors, and design the geometry of the machining core mold and the blank shape of the workpiece.

[0014] S2. When installing the workpiece and the core mold, first fix the workpiece on the workpiece turntable with the mold and bolts, drive the slider to the core mold installation position with the main oil cylinder, install the core mold on the main shaft from top to bottom, and lock it with bolts, so that the core mold can move in the inner hole of the workpiece.

[0015] S3. During equipment processing, the slider moves quickly to the processing position, the stop extends, locks the slider so that it stops moving, and then controls the main spindle motor and the workpiece motor to move in linkage, thereby driving the core 23 and the workpiece to rotate in linkage according to the set transmission ratio. Further, according to the set core mold spatial motion, the six drive motors are controlled to perform 6-axis linkage motion, so that the core mold can rotate along the axis while performing multi-degree-of-freedom spatial motion. Finally, additional motion is added to the six drive motors on the basis of linkage motion, so that the core mold can perform multi-degree-of-freedom spatial motion while performing feed motion along the slider axis, thereby making the core mold gradually approach the workpiece and squeeze the inner wall of the workpiece, ultimately forming the required complex thin-walled high-rib inner wall geometry of the workpiece.

[0016] S4. After the equipment finishes processing, the direction of the additional motion of the six drive motors is changed, so that the core mold gradually moves away from the inner wall of the workpiece along the axis of the slider while performing spatial forming motion. When the core mold is completely removed from the inner wall of the workpiece, the linkage rotation of the core mold and the workpiece is stopped at the same time, the block lock on the slider is released, and the slider is driven to the core mold installation position by the main oil cylinder. The core mold and the main shaft are released, and the core mold is pulled out from the main shaft from bottom to top. Then the slider is driven to the ejection position, the workpiece and the workpiece turntable are released from the fixation, and the cylinder rod of the ejection oil cylinder is driven to move upward, ejecting the workpiece from the workpiece turntable.

[0017] This invention also provides a motion control method for the aforementioned eight-axis linkage six-bar parallel radial plastic forming robot, which achieves precise control of the equipment by establishing a correspondence between the core mold motion and the rotation axis motion, including:

[0018] Establish a coordinate system S0 at the center of the left bed, with its z0 axis along the slider motion axis, and its x0 and y0 axes in a vertical plane. The x0y0 plane is set at the center of the ball joints connecting all drive shafts to the connecting rods, and is defined as the left bed plane. The intersection points of the six drive shaft axes with this left bed plane are set as A1, A2…A6, respectively, and their position vectors in the S0 coordinate system are set as follows:

[0019]

[0020] In the formula, Center point A of the drive shaft i The positions in the x and y directions represent the configuration parameters of the equipment;

[0021] The centers of the ball joints connected to the connecting rods on the six drive shafts are designated as C1, C2…C6, respectively, and their position vectors are:

[0022]

[0023] In the formula θ i Let be the rotation angle of the i-th drive shaft, and e be the eccentricity of the drive shaft;

[0024] Establish a coordinate system S1 at the center of the core mold on the main spindle, with its y1 axis along the axis of the main spindle 6 and its z1 axis perpendicular to the plane where the main spindle seat is located; the centers of the ball joints connected to the connecting rod on the main spindle seat are set as B1, B2…B6, and their position vectors in coordinate system S1 are:

[0025]

[0026] In the formula, Main spindle seat connecting rod center point B i The x, y, and z directions represent the position, which are the configuration parameters of the equipment;

[0027] Assuming the spatial motion of the principal axis is [x,y,z,α,β,γ], where x,y,z are the platforms of the principal axis along the three coordinate axes, and α,β,γ are the rotations of the principal axis around the three coordinate axes; then the coordinate transformation between coordinate system S0 and coordinate system S1 is:

[0028]

[0029] Generally, to achieve local shaping, a swing feed motion mode is adopted, with the following motion parameters:

[0030]

[0031] In the formula, ω is the oscillation frequency of the oscillating head, and k is the feed rate;

[0032] The position vector of points B1, B2…B6 in the coordinate system is S0:

[0033]

[0034] Therefore, the position vector of the connecting rod is:

[0035]

[0036] Based on the condition that the length of the connecting rod remains constant, we have the following constraint equations:

[0037]

[0038] In the formula, l is the length of the connecting rod; according to the above equation (8), the rotation angle θ of the shaft can be solved. i ;

[0039] Given a point q1 = [q on the spindle seat of a spatial envelope forming equipment] x ,q y ,q z ] T Then the trajectory of the motion of that point is:

[0040]

[0041] The eight-axis linkage six-bar parallel radial plastic forming robot of the present invention has the following beneficial effects:

[0042] 1. This invention achieves high rigidity, high motion flexibility, and high resistance to eccentric loads in radial forming equipment through a multi-link parallel drive structure, enabling one-time forming of large thin-walled, high-ribbed cylindrical parts under heavy load conditions of thousands of tons.

[0043] 2. This invention adopts a direct-drive dual-spindle structure. The movement of the workpiece shaft and the spindle is achieved by the control system to achieve a constant transmission ratio. It has the advantages of simple structure and mature control technology.

[0044] 3. The present invention adopts a horizontal bed structure, and the workpiece is placed vertically during forming. The workpiece can be directly hoisted onto the workpiece shaft, which has the advantages of convenient operation and simple process. Attached Figure Description

[0045] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0046] Figure 1 is a schematic diagram of the structure of the eight-axis linkage six-bar parallel radial plastic forming robot of the present invention;

[0047] Figure 2 is a front view of the eight-axis linkage six-bar parallel radial plastic forming robot of the present invention;

[0048] Figure 3 is a top view of the eight-axis linkage six-bar parallel radial plastic forming robot of the present invention;

[0049] Figure 4 is a schematic diagram of the kinematic geometry of the eight-axis linkage six-bar parallel radial plastic forming robot of the present invention;

[0050] Figure 5 is a schematic diagram of the drive shaft rotation angle;

[0051] Figure 6 is a schematic diagram of the trajectory of different points on the space workbench. Detailed Implementation

[0052] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0053] As shown in Figures 1-3, the eight-axis linkage six-bar parallel radial plastic forming robot of the present invention includes a left bed 7 and a right bed 16, which are fixedly connected by a square column 8 and a tie rod therein.

[0054] Six reducers 2 are installed and fixed on the left bed 7 in a certain spatial distribution. The input end of the reducer 2 is connected to the corresponding drive motor 1 through a coupling, and the output end of the reducer 2 is fixedly connected to the corresponding drive shaft 3. The drive shaft 3 is connected to the left bed 7 through bearings, so it can rotate around the axis of the reducer on the left bed 7. The drive shaft 3 is an eccentric shaft, and its eccentric end is constrained by a ball joint to form a dynamic fit with the corresponding connecting rod 4. The other end of the corresponding connecting rod 4 is also constrained by a ball joint to form a fit with the spindle seat 5. The six sets of connecting rods 4 are installed in parallel on the spindle seat 5 to form a complete spatial constraint. Therefore, the spatial position and attitude of the spindle seat 5 can be adjusted by controlling the position of the six drive motors 1. At the same time, the spindle seat 5 is also connected to the left bed 7 through four damping rods 22 to improve the stability of the movement.

[0055] A spindle 6 is mounted on the spindle seat 5 via bearings. The spindle 6 is driven by a main reducer 10 and a main motor 9 mounted at its lower end. A mandrel 23 is mounted on the spindle, allowing it to rotate under the drive of the main motor 9. A slide block 15 is mounted on the right bed 16 via four guide rails. The front end of the slide block 15 is connected to the main hydraulic cylinder 20 via a main tie rod 21, allowing the slide block 15 to move along the guide rail axis under the constraint of the guide rails and the drive of the main hydraulic cylinder 20. A workpiece turntable 13 is mounted on the center of the slide block 15 via bearings. The workpiece turntable 13 can rotate on the slide block 15 along its axis, driven by a workpiece reducer 12 and a workpiece motor 11 mounted on the slide block 15.

[0056] Workpiece 14 is mounted on workpiece turntable 13 via a mold and can rotate with workpiece turntable 13. Stops 17 are mounted on both sides of the right bed 16. Driven by stop cylinders 19, the stops 17 can move along the axis perpendicular to the slider 15, thus fixing the slider's machining position. An ejector cylinder 18 is mounted at the lower end of the right bed 16. Driven by hydraulic oil, the ejector cylinder 18 can move up and down to eject the workpiece.

[0057] The power transmission process of the eight-axis linkage six-bar parallel radial plastic forming robot is as follows:

[0058] The power source for this equipment includes six drive motors 1, a spindle motor 9, a workpiece motor 11, a stop cylinder 19, an ejector cylinder 18, and a main cylinder 20. The main cylinder 20 drives the slider 15 to move, realizing the rapid forward and rapid backward movement of the workpiece 14. The stop cylinder 19 drives the stop 17 to move, fixing the position of the slider 15. The ejector cylinder 18 extends upward, ejecting the workpiece 14. The spindle motor 9 drives the spindle reducer 10 to move, and the spindle reducer 10 drives the spindle 6 and the mandrel 23 mounted on it to rotate, realizing the rotational motion control of the mandrel 23. The workpiece motor 11 drives the workpiece reducer 12 to rotate, and the workpiece reducer 12 drives the workpiece turntable 13 and the workpiece 14 mounted on it to rotate, thereby realizing the motion control of the workpiece 14; the six drive motors 1 move simultaneously, driving the corresponding reducers 2 to rotate, the reducers 2 drive the drive shaft 3 connected to them to rotate, and the drive shaft 3 drives the connecting rod 4 mounted on it to move in space, so that the main spindle 6 on the main spindle seat 5 and the core mold 23 move in space under the coordinated action of the spatial movement of the six connecting rods 4, and finally realize the multi-degree-of-freedom spatial forming motion posture control of the core mold 23.

[0059] The present invention also provides a method for machining thin-walled, high-ribbed cylindrical parts using the aforementioned eight-axis linkage six-bar parallel radial plastic forming robot, as detailed below:

[0060] 1) During process design, multi-degree-of-freedom spatial forming motion is selected based on the geometric switching characteristics of workpiece 14, generating motion data for six drive motors 1, and designing the geometry of the core mold 23 and the blank shape of workpiece 14.

[0061] 2) When installing workpiece 14 and core mold 23, first fix workpiece 14 on workpiece turntable 13 with mold and bolts, drive slider 15 to move to core mold installation position by main cylinder 20 (at this time, the axis of movement of workpiece 14 coincides with the axis of rotation of main shaft 6), install core mold 23 on main shaft 6 from top to bottom, and lock it with bolts, so that core mold 23 can move in the inner hole of workpiece 14.

[0062] 3) During equipment processing, the slider 15 moves quickly to the processing position, the stop block 17 extends and locks the slider 15 so that it stops moving. Then, the spindle motor 9 and the workpiece motor 11 are controlled to move in linkage, thereby driving the core 23 and the workpiece 14 to rotate in linkage according to the set transmission ratio. Further, according to the set core mold spatial motion, the six drive motors 1 are controlled to perform 6-axis linkage motion, so that the core mold 23 can perform multi-degree-of-freedom spatial motion while rotating along the axis. Finally, additional motion is added to the six drive motors 1 on the basis of linkage motion, so that the core mold 23 can perform multi-degree-of-freedom spatial motion while performing feed motion along the axis of slider 15, so that the core mold 23 gradually approaches the workpiece 14 and squeezes the inner wall of the workpiece 14, ultimately forming the required complex thin-walled high-rib inner wall geometry of the workpiece 14.

[0063] 4) After the equipment finishes processing, the direction of the additional motion of the six drive motors is changed, so that the core mold 23 gradually moves away from the inner wall of the workpiece 14 along the axis of the slider 15 while performing spatial forming motion. When the core mold 23 is completely removed from the inner wall of the workpiece 14, the linkage rotation of the core mold 23 and the workpiece 14 is stopped, the locking of the stop block 17 on the slider 15 is released, and the slider 15 is driven to move to the core mold installation position through the main cylinder 20. The bolt lock between the core mold 23 and the main shaft 6 is released, and the core mold 23 is pulled out from the main shaft 6 from bottom to top. Then the slider 15 is driven to move to the ejection position (at this time, the axis of the workpiece 14 coincides with the axis of the ejection cylinder 18), the bolt fixing between the workpiece 14 and the workpiece turntable 13 is released, and the cylinder rod of the ejection cylinder 18 is driven to move upward, ejecting the workpiece from the workpiece turntable 13.

[0064] This invention also provides a motion control method for the kinematic relationship of an eight-axis linkage six-bar parallel radial plastic forming robot. Based on the equipment structure described above, in order to achieve the specific spatial motion requirements of the mandrel, it is necessary to establish the correspondence between the mandrel motion and the rotation axis motion, thereby achieving precise control of the equipment. This can be deduced as follows.

[0065] Establish a coordinate system S0 at the center of the left bed, with its z0 axis along the slider motion axis, and its x0 and y0 axes in a vertical plane. The x0y0 plane is set at the center of the ball joints connecting all drive shafts to the connecting rods, and is defined as the left bed plane. The intersection points of the six drive shaft axes with this left bed plane are set as A1, A2…A6, respectively, and their position vectors in the S0 coordinate system are set as…

[0066]

[0067] In the formula, Center point A of the drive shaft i The positions in the x and y directions represent the configuration parameters of the equipment.

[0068] The centers of the ball joints connected to the connecting rods on the six drive shafts are designated as C1, C2…C6, respectively, and their position vectors are:

[0069]

[0070] In the formula θ i Let be the rotation angle of the i-th drive shaft, and e be the eccentricity of the drive shaft.

[0071] Establish a coordinate system S1 at the center of the mandrel on the main spindle, with its y1 axis along the axis of the main spindle 6 and its z1 axis perpendicular to the plane containing the main spindle seat. Let the centers of the ball joints connected to the connecting rod on the main spindle seat be B1, B2…B6, and their position vectors in coordinate system S1 be...

[0072]

[0073] In the formula, Main spindle seat connecting rod center point B i The x, y, and z directions represent the position, which are the configuration parameters of the equipment.

[0074] Assume the spatial motion of the principal axis is [x, y, z, α, β, γ], where x, y, z are the platforms of the principal axis along the three coordinate axes, and α, β, γ are the rotations of the principal axis around the three coordinate axes. Then the coordinate transformation between coordinate system S0 and coordinate system S1 is:

[0075]

[0076] Generally, to achieve local shaping, a swing feed motion mode is adopted, with the following motion parameters:

[0077]

[0078] In the formula, ω is the oscillation frequency of the oscillating head, and k is the feed rate.

[0079] Furthermore, the position vectors of points B1, B2…B6 in the coordinate system are S0:

[0080]

[0081] Therefore, the position vector of the connecting rod is:

[0082]

[0083] Based on the condition that the length of the connecting rod remains constant, we have the following constraint equations:

[0084]

[0085] In the formula, l is the length of the connecting rod. Based on the above equation (8), the rotation angle θ of the shaft can be solved. i .

[0086] Furthermore, given a point q1 = [q on the spindle seat of the spatial envelope forming equipment] x ,q y ,q z ] T Then the trajectory of the motion of that point is:

[0087]

[0088] Based on the above design process of an eight-axis linkage six-bar parallel radial plastic forming robot, a set of configuration parameters of the forming equipment can be obtained as shown in Table 1.

[0089] Table 1 Equipment Configuration Parameters

[0090]

[0091] Under these parameters, the angle variation curves of each drive shaft are shown in Figure 5, and the trajectories of different points on the space worktable are shown in Figure 6.

[0092] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. An eight-axis linkage six-bar parallel radial plastic forming robot, characterized in that, The machine includes a left bed and a right bed. Six reducers are fixedly mounted on the left bed. The input end of each reducer is connected to the corresponding drive motor via a coupling, and the output end is fixedly connected to the corresponding drive shaft. The drive shaft, an eccentric shaft, is connected to the left bed. Its eccentric end is dynamically engaged with the corresponding connecting rod via a ball joint constraint, and the other end of the corresponding connecting rod is also engaged with the spindle seat via a ball joint constraint. The six sets of connecting rods are simultaneously mounted in parallel on the spindle seat, forming a complete spatial constraint. The spindle seat is connected to the left bed via a damping rod. The spindle is mounted on the spindle seat and driven by the main reducer and main motor. A mandrel is mounted on the spindle. A slider is mounted on the right bed via four guide rails. The front end of the slider is connected to the main hydraulic cylinder. Under the constraint of the guide rails and driven by the main hydraulic cylinder, the slider can move along the guide rail axis. A workpiece turntable is mounted at the center of the slider. The workpiece turntable can rotate along the axis of the slider, driven by a workpiece reducer and workpiece motor mounted on the slider. The workpiece is mounted on the workpiece turntable via a mold and can rotate with the workpiece turntable.

2. The eight-axis linkage six-bar parallel radial plastic forming robot according to claim 1, characterized in that, The drive shaft is connected to the left bed via bearings.

3. The eight-axis linkage six-bar parallel radial plastic forming robot according to claim 1, characterized in that, The spatial position and attitude of the spindle seat are adjusted by controlling the position of the six drive motors.

4. The eight-axis linkage six-bar parallel radial plastic forming robot according to claim 1, characterized in that, The left and right beds are fixedly connected by square columns and tie rods therein.

5. The eight-axis linkage six-bar parallel radial plastic forming robot according to claim 1, characterized in that, Both sides of the right bed are equipped with stops. The stops can move along the axis perpendicular to the slider under the drive of the stop cylinder, so as to fix the slider machining position.

6. The eight-axis linkage six-bar parallel radial plastic forming robot according to claim 1, characterized in that, An ejector cylinder is installed at the lower end of the right bed. The ejector cylinder can move up and down under the drive of hydraulic oil to eject the workpiece.

7. The eight-axis linkage six-bar parallel radial plastic forming robot according to claim 1, characterized in that, The core mold rotates under the drive of the main motor.

8. The eight-axis linkage six-bar parallel radial plastic forming robot according to claim 1, characterized in that, The front end of the slider is connected to the main hydraulic cylinder via a main tie rod.

9. A method for machining thin-walled, high-ribbed cylindrical parts using the eight-axis linkage six-bar parallel radial plastic forming robot as described in claim 1, characterized in that, Includes the following steps: S1. Select multi-degree-of-freedom spatial forming motion based on the geometric switching characteristics of the workpiece, generate motion data for six drive motors, and design the geometry of the machining core mold and the blank shape of the workpiece. S2. When installing the workpiece and mandrel, first fix the workpiece on the workpiece turntable using molds and bolts. Drive the slider to the mandrel installation position using the main hydraulic cylinder, and install the mandrel onto the main spindle from top to bottom. Lock it with bolts, allowing the mandrel to move within the inner hole of the workpiece. S3. During processing, the slider quickly moves to the processing position, the stop extends, and locks the slider, preventing further movement. Then, control the main spindle motor and workpiece motor to move in tandem, driving the mandrel 23 and workpiece to rotate in tandem according to the set transmission ratio. Further, based on the set mandrel spatial motion, control the six drive motors to perform 6-axis tandem motion, allowing the mandrel to rotate along the axis while simultaneously performing multi-degree-of-freedom spatial motion. Finally, add additional motion to the six drive motors on top of the tandem motion, enabling the mandrel to perform multi-degree-of-freedom spatial motion simultaneously. The core mold moves along the axis of the slider, gradually approaching the workpiece and pressing against its inner wall to form the desired complex thin-walled, high-ribbed inner wall geometry. S4: After processing, the direction of the six drive motors is changed, causing the core mold to move away from the workpiece's inner wall while simultaneously forming in space. When the core mold is completely removed from the workpiece's inner wall, the linkage between the core mold and the workpiece stops, the stop block is released from locking the slider, and the main cylinder drives the slider to the core mold installation position, releasing the lock between the core mold and the main shaft. The core mold is then pulled out from the main shaft from bottom to top. Subsequently, the slider is driven to the ejection position, releasing the workpiece from the workpiece turntable and driving the ejection cylinder rod upwards to eject the workpiece from the workpiece turntable.

10. A motion control method for an eight-axis linkage six-bar parallel radial plastic forming robot as described in claim 1, characterized in that, By establishing the correspondence between the core mold motion and the rotating shaft motion, precise control of the equipment is achieved, including: establishing a coordinate system S0 at the center of the left bed, with its z0 axis along the slider motion axis, and its x0 and y0 axes in a vertical plane. The x0y0 plane is set at the center of the ball joints connected to the connecting rods on all drive shafts, and is defined as the left bed plane; the intersection points of the axes of the six drive shafts and this left bed plane are respectively set as A1, A2…A6, and their position vectors in the S0 coordinate system are set as: In the formula, Center point A of the drive shaft i The positions in the x and y directions represent the configuration parameters of the equipment; the centers of the ball joints connected to the connecting rods on the six drive shafts are set as C1, C2…C6, respectively, and their position vectors are: In the formula θ i Let be the rotation angle of the i-th drive shaft, and e be the eccentricity of the drive shaft; establish a coordinate system S1 at the center of the mandrel on the main shaft, with y1 along the axis of the main shaft 6 and z1 perpendicular to the plane where the main shaft seat is located; let the centers of the ball joints connected to the connecting rod on the main shaft seat be B1, B2…B6, and their position vectors in coordinate system S1 be: In the formula, Main spindle seat connecting rod center point B i Let x, y, and z be the positions, which are the configuration parameters of the equipment; assuming the spatial motion of the main axis is [x, y, z, α, β, γ], where x, y, and z are the platforms of the main axis along the three coordinate axes, and α, β, and γ are the rotations of the main axis around the three coordinate axes; then the coordinate transformation between coordinate system S0 and coordinate system S1 is: Generally, to achieve local shaping, a swing feed motion mode is adopted, with the following motion parameters: In the formula, ω is the oscillation frequency of the oscillating head, k is the feed rate; the position vector of points B1, B2…B6 in the coordinate system is S0: Therefore, the position vector of the connecting rod is: Based on the condition that the length of the connecting rod remains constant, we have the following constraint equations: In the formula, l is the length of the connecting rod; according to the above equation (8), the rotation angle θ of the shaft can be solved. i Given a point q1 = [q on the spindle seat of a spatial envelope forming equipment] x ,q y ,q z ] T Then the trajectory of the motion of that point is:

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