Control method for a non-equal arm independent vacuum robot

Abstract

The application provides a control method of an unequal-arm independent vacuum manipulator, comprising the following steps: S1: the vacuum manipulator sets a corresponding control mode according to an instruction sent by an upper computer and in combination with a taught work station position, wherein the control mode comprises single picking and single placing, multiple picking and multiple placing, and cross picking and placing; S2: a motion trajectory is planned according to the selected control mode and the work station position; S3: the motion trajectory is decoupled from a position point by transforming a manipulator joint coordinate system and a motor coordinate system through a forward or reverse kinematics algorithm; and S4: the vacuum manipulator transports a wafer according to the decoupled position point and according to the motion trajectory. In the wafer transmission process, the vacuum manipulator supports multiple transmission modes, including single-robot-arm assembly picking and placing, double-robot-arm assembly simultaneous picking and placing, and double-robot-arm assembly cross picking and placing, so that the wafer transmission efficiency of the manipulator is maximally improved.

Description

Technical Field

[0001] This invention relates to the field of robotic arm technology, and in particular to a control method for an unequal-arm independent vacuum robotic arm. Background Technology

[0002] One existing solution uses an upper and lower arm configuration, with each arm employing two motors to control the movement of the upper arm and lower arm respectively. The extension and retraction of the robotic arm is achieved through the linkage of the two motors. This solution only supports the handling of a single wafer and cannot handle two wafers simultaneously, which limits the transmission efficiency of the entire transmission system.

[0003] Another existing solution uses a QUADRAFLY arm, in which a single robotic arm drives the left and right end effectors to simultaneously transfer two wafers during wafer transfer. However, the left and right end effectors must extend into the workstation at the same time, making it impossible to independently pick up and put down the left and right end effectors, and it is impossible to exchange the hand movements, thus making it impossible to complete complex transfer tasks.

[0004] In view of this, it is necessary to propose a control method for an unequal-arm independent vacuum manipulator to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a control method for an unequal-arm independent vacuum manipulator, in order to improve the problem that existing manipulators do not support multiple transmission methods.

[0006] This invention provides a control method for an unequal-arm independent vacuum manipulator, comprising:

[0007] S1: The vacuum robot arm sets the corresponding control mode according to the instructions sent by the host computer and in combination with the taught workstation position. The control mode includes single pick-up and single placement, multiple pick-up and multiple placement, and cross pick-up and placement.

[0008] S2: Based on the selected control mode and the workstation position, the motion trajectory is planned;

[0009] S3: By transforming the joint coordinate system and the motor coordinate system of the robot arm through forward or backward kinematics algorithms, the motion trajectory is decoupled from the position point.

[0010] S4: The vacuum robot arm transports the wafer according to the decoupled position point and the motion trajectory.

[0011] In one possible embodiment, the vacuum manipulator includes N robotic arm assemblies, a lifting motor, a rotary motor, and N telescopic motors. The lifting motors are used to drive all the robotic arm assemblies to lift synchronously, the rotary motors are used to drive all the robotic arm assemblies to rotate synchronously, and the telescopic motors are configured one-to-one with the robotic arm assemblies and are used to drive the corresponding robotic arm assembly to extend and retract. Here, N is a positive integer greater than 1.

[0012] The transformation between the robot joint coordinate system and the motor coordinate system includes: the transformation between the polar coordinate system of the robot joint and the coordinate system of the lifting motor, the transformation between the polar coordinate system of the robot joint and the coordinate system of the rotary motor, and the transformation between the polar coordinate system of the robot joint and the coordinate system of the telescopic motor.

[0013] In one possible embodiment, the joint coordinates of the vacuum manipulator are defined as [R1, ... R2]. N The motor coordinates are defined as [Tz, T1, ..., Tz]. N [,To], where R1, ..., R N Let X be the telescopic joint position of the first to the Nth robotic arm assembly, Z be the rotary joint position of the vacuum manipulator, Tz be the lifting joint position of the vacuum manipulator, and T1, ..., T2 be the encoder value of the lifting motor. N These are the encoder values ​​for the first to the Nth telescopic motors, respectively, and To is the encoder value for the rotary motor;

[0014] Step S3 includes:

[0015] The position X of the rotary joint of the vacuum manipulator is converted to the corresponding value To of the encoder of the rotary motor;

[0016] The lifting joint position Z of the vacuum manipulator is converted to the encoder value Tz of the lifting motor.

[0017] The telescopic joint position R of the robotic arm assembly and the encoder value T of the telescopic motor are converted into a one-to-one correspondence through a forward or reverse kinematic algorithm.

[0018] In one possible implementation, the forward kinematics algorithm employs the following formula:

[0019] ;

[0020] ;

[0021] get ;

[0022] The robotic arm assembly includes a first arm and a second arm. The telescopic motor drives the first arm to rotate, thereby causing the second arm to rotate. L1 is the effective length of the first arm, L2 is the effective length of the second arm, D is the length difference between the first arm and the second arm in the Y-axis direction, θ1 is the angle between the first arm and the Y-axis direction, θ2 is the angle between the second arm and the Y-axis direction, and R is the telescopic joint position of the robotic arm assembly.

[0023] In one possible implementation, the inverse kinematics algorithm uses the following formula:

[0024] ;

[0025] ;

[0026] get ;

[0027] The robotic arm assembly includes a first arm and a second arm. The telescopic motor drives the first arm to rotate, thereby causing the second arm to rotate. L1 is the effective length of the first arm, L2 is the effective length of the second arm, D is the length difference between the first arm and the second arm in the Y-axis direction, θ1 is the angle between the first arm and the Y-axis direction, θ2 is the angle between the second arm and the Y-axis direction, and R is the telescopic joint position of the robotic arm assembly.

[0028] In one possible embodiment, the corresponding encoder value T of the telescopic motor is calculated using the angle θ1 between the first arm and the Y-axis direction, so that the telescopic motor can drive the robotic arm assembly to adjust the telescopic joint position R of the robotic arm assembly according to the encoder value T.

[0029] In one possible embodiment, at least two sensors are provided on the conveying path of the robotic arm assembly corresponding to each workstation;

[0030] During the wafer transfer process of the robotic arm assembly, the actual position of the wafer center is detected and calculated by the sensor, and then it is determined whether the wafer is eccentric. If the wafer is eccentric, the eccentric position of the wafer is calculated, and a correction value is obtained based on the eccentric position and the workstation position. The correction value is used to correct the wafer position.

[0031] In one possible embodiment, detecting and calculating the actual position of the wafer center using the sensor includes:

[0032] When the edge of the wafer passes the sensor, the trigger point position corresponding to each trigger is obtained, and all the trigger point positions are converted into corresponding Cartesian coordinate values ​​through a forward kinematics algorithm;

[0033] The actual position of the wafer center is calculated using a least-squares fitting algorithm based on all the Cartesian coordinate values.

[0034] In one possible embodiment, the actual position of the wafer center is calculated using a least-squares fitting algorithm based on all the Cartesian coordinate values, including:

[0035] For each of the Cartesian coordinate values ​​( x i , y i The equation of the circle is: ;

[0036] Combining the circle equations of all the Cartesian coordinate values ​​yields a system of linear equations. Transforming this system of linear equations into matrix form yields... A ⋅[ D , E , F ] T = b ;

[0037] Calculate using the pseudo-inverse matrix [ D , E , F ]=( A T A ) −1 A T b The actual position of the wafer center is obtained as follows: (−D / 2,−E / 2) ;

[0038] in, D, E, F All are coefficients of the circle equation, ( x i , y i ) is the first i Cartesian coordinates, A For the constructed matrix, b The vector to be constructed.

[0039] In one possible embodiment, obtaining the correction value based on the eccentric position and the workstation position includes:

[0040] The eccentric position of the robotic arm assembly in the finger center coordinate system is converted into the eccentric position in the corresponding workstation coordinate system.

[0041] The correction value is obtained based on the eccentric position in the workstation coordinate system and the workstation position.

[0042] The beneficial effects of the control method for the unequal-arm independent vacuum manipulator provided by this invention are as follows: During wafer transfer, the vacuum manipulator supports multiple transfer modes, including single-arm component wafer pick-and-place, simultaneous pick-and-place of wafers by two arm components, and cross pick-and-place of wafers by two arm components, maximizing the manipulator's wafer transfer efficiency. In a further embodiment, forward or backward kinematic algorithms are used to control the extension joint movement of a single arm component with a single telescopic motor, supporting independent extension and retraction movements of a single arm component, reducing the complexity and additional cost of the vacuum manipulator. In an even further embodiment, different control modes all support wafer eccentricity calculation, effectively improving wafer placement accuracy. Attached Figure Description

[0043] Figure 1 This is a flowchart illustrating the control method of the unequal-arm independent vacuum manipulator of the present invention.

[0044] Figure 2 This is a simplified flowchart of the control method for the unequal-arm independent vacuum manipulator of the present invention.

[0045] Figure 3 This is a schematic diagram of the unequal-arm independent vacuum robot, sensor, and workstation of the present invention.

[0046] Figure 4 This is a schematic diagram of the unequal-arm independent vacuum manipulator of the present invention.

[0047] Figure 5 This is a schematic diagram of the single-arm plate picking method of the control method of the unequal-arm independent vacuum manipulator of the present invention.

[0048] Figure 6 This is a schematic diagram of the control method of the unequal-arm independent vacuum manipulator of the present invention, showing the simultaneous picking up of plates by both arms.

[0049] Figure 7 This is a schematic diagram of the double-arm cross-grabbing method of the control method of the unequal-arm independent vacuum manipulator of the present invention.

[0050] Explanation of reference numerals in the attached drawings: 500, vacuum robot; 510, robot arm assembly; 511, first arm; 512, second arm; 600, wafer; 700, sensor; 800, workstation. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0052] To address the problems existing in the prior art, embodiments of the present invention provide a control method for an unequal-arm independent vacuum manipulator, see [link to relevant documentation]. Figure 1 , Figure 2 as well as Figure 3 The control method includes:

[0053] S1: Control mode selection: The vacuum robot 500 selects the corresponding control mode according to the instructions sent by the host computer and the position of the taught workstation 800. The control modes include single pick-up and single place, multiple pick-up and multiple place, and cross pick-up and place.

[0054] S2: Trajectory planning and processing: Based on the selected control mode and workstation 800 position, the motion trajectory is planned;

[0055] S3: Position point decoupling: By transforming the joint coordinate system and the motor coordinate system of the robot arm through forward or backward kinematics algorithms, the position point of the motion trajectory is decoupled;

[0056] S4: Motion control: The vacuum robot 500 transports the wafer 600 according to the decoupled position point and the motion trajectory.

[0057] In this embodiment, the vacuum robot 500 supports multiple control modes, including: single pick-up and single placement mode, where only one selected robotic arm assembly 510 is controlled to pick up and place the wafer 600, while other unselected robotic arm assemblies 510 remain retracted; multiple pick-up and multiple placement mode, where at least two selected robotic arm assemblies 510 are controlled to extend and retract simultaneously to complete the pick-up and placement operation; and cross pick-up and placement mode, where at least two selected robotic arm assemblies 510 are controlled to perform cross extension and retraction movements to cross pick up and place the wafer 600. Therefore, the vacuum robot 500 in this solution can flexibly meet different wafer transfer requirements and maximize the wafer transfer efficiency of the robot system.

[0058] In one embodiment, see Figure 4The vacuum robotic arm 500 includes N robotic arm components 510, a lifting motor, a rotary motor, and N telescopic motors. The lifting motors drive all robotic arm components 510 to lift synchronously, the rotary motors drive all robotic arm components 510 to rotate synchronously, and the telescopic motors are configured one-to-one with each robotic arm component 510 to drive the corresponding robotic arm component 510 to extend or retract. Here, N is a positive integer greater than 1. The polar coordinate system of the robotic arm joints has its origin at the base center of the vacuum robotic arm 500. The transformation between the robotic arm joint coordinate system and the motor coordinate system includes transformations between the polar coordinate system of the robotic arm joints and the lifting motor coordinate system, between the polar coordinate system of the robotic arm joints and the rotary motor coordinate system, and between the polar coordinate system of the robotic arm joints and the telescopic motor coordinate system.

[0059] In a preferred embodiment, see Figure 4 The joint coordinates of the vacuum manipulator 500 are defined as [R1, ... R2]. N The motor coordinates are defined as [Tz, T1, ..., Tz]. N [,To], where R1, ..., R N T1, ..., T2 represent the telescopic joint positions of the first to Nth robotic arm components 510, in μm; X represents the rotary joint position of the vacuum robotic arm 500, in mdeg; Z represents the lifting joint position of the vacuum robotic arm 500, in μm; Tz represents the encoder value of the lifting motor; T1, ..., T2 represent the position of the telescopic joint of the first to Nth robotic arm components 510, in μm; T2 represents the position of the rotary joint of the vacuum robotic arm 500, in μm; T3 represents the position of the lifting motor encoder value; T4, ..., T2 represent the position of the telescopic joint of the first to Nth robotic arm components 510, in μm; T5 represents the position of the rotary joint of the vacuum robotic arm 500, in mdeg; T6 represents the position of the lifting joint of the vacuum robotic arm 500, in μm; T7 represents the position of the lifting motor encoder value; T8 represents the position of the telescopic joint of the N These are the encoder values ​​for the first to Nth telescopic motors, respectively; To is the encoder value for the rotary motor.

[0060] Step S3 includes: the conversion of the rotary joint position X of the vacuum manipulator 500 to the encoder value To of the rotary motor; the conversion of the lifting joint position Z of the vacuum manipulator 500 to the encoder value Tz of the lifting motor; and the conversion of the telescopic joint position R of the robotic arm assembly 510 to the encoder value T of the telescopic motor through a one-to-one correspondence using a forward or reverse kinematics algorithm.

[0061] In this embodiment, each robotic arm assembly 510 is driven by a telescopic motor for telescopic adjustment. By using forward or reverse kinematic algorithms, the corresponding conversion between the telescopic joint position R of the robotic arm assembly 510 and the encoder value T of the telescopic motor is realized. That is, each telescopic motor can control the extension joint movement of the corresponding robotic arm assembly 510 according to the telescopic requirements of the corresponding robotic arm assembly 510, i.e., the telescopic joint position R, to realize the picking and placing of pieces in different control modes.

[0062] In one specific embodiment, the forward kinematics algorithm in the above embodiments adopts the following formula:

[0063] ; ;

[0064] get ;

[0065] Among them, see Figure 4 The robotic arm assembly 510 includes a first arm 511 and a second arm 512. A telescopic motor drives the first arm 511 to rotate, which in turn drives the second arm 512 to rotate. L1 is the effective length of the first arm 511, L2 is the effective length of the second arm 512, D is the length difference between the first arm 511 and the second arm 512 in the Y-axis direction, θ1 is the angle between the first arm 511 and the Y-axis direction, θ2 is the angle between the second arm 512 and the Y-axis direction, and R is the telescopic joint position of the robotic arm assembly 510.

[0066] In one specific embodiment, the inverse kinematics algorithm in the above embodiments adopts the following formula:

[0067] ; ;

[0068] get ;

[0069] Among them, see Figure 4 The robotic arm assembly 510 includes a first arm 511 and a second arm 512. A telescopic motor drives the first arm 511 to rotate, which in turn drives the second arm 512 to rotate. L1 is the effective length of the first arm 511, L2 is the effective length of the second arm 512, D is the length difference between the first arm 511 and the second arm 512 in the Y-axis direction, θ1 is the angle between the first arm 511 and the Y-axis direction, θ2 is the angle between the second arm 512 and the Y-axis direction, and R is the telescopic joint position of the robotic arm assembly 510.

[0070] The first arm 511 and the second arm 512 are linked and driven according to a set transmission ratio. The telescopic motor drives the first arm 511 to rotate, and through the transmission mechanism between the first arm 511 and the second arm 512, the second arm 512 is also driven to rotate. In other words, under the driving action of a telescopic motor, the first arm 511 and the second arm 512 of the corresponding robotic arm assembly 510 can be driven to rotate synchronously, thereby realizing the telescopic adjustment of the robotic arm assembly 510.

[0071] In one specific embodiment, the corresponding encoder value T of the telescopic motor is calculated by using the angle θ1 between the first arm 511 and the Y-axis direction, so that the telescopic motor can drive the robotic arm assembly 510 to achieve the telescopic adjustment of the telescopic joint position R of the robotic arm assembly 510 according to the encoder value T of the telescopic motor.

[0072] The angle θ1 between the first arm 511 and the Y-axis direction in the forward or reverse kinematics algorithm of the above embodiments, that is, the rotation angle of the first arm 511, is as follows: Figure 4 As shown, since the rotation of the first arm 511 is controlled by the corresponding telescopic motor, the encoder value T of the telescopic motor required for the rotation angle θ1 of the first arm 511 can be calculated.

[0073] In one embodiment, see Figure 3 and Figure 4 At least two sensors 700 are set along the conveying path of the robotic arm assembly 510 for each workstation 800. During the conveying of the wafer 600 by the robotic arm assembly 510, the actual position of the center of the wafer 600 is detected and calculated by the sensors 700, thereby determining whether the wafer 600 is off-center. If the wafer 600 is off-center, the off-center position of the wafer 600 is calculated, and a correction value is obtained based on the off-center position and the position of the workstation 800. The correction value is used to correct the position of the wafer 600.

[0074] In a preferred embodiment, see Figure 3 The actual position of the center of wafer 600 is detected and calculated by sensor 700, including: obtaining the trigger point position corresponding to each trigger when the edge of wafer 600 passes sensor 700, converting all trigger point positions into corresponding Cartesian coordinate values ​​through a forward kinematics algorithm; and calculating the actual position of the center of wafer 600 using a least squares fitting algorithm based on all Cartesian coordinate values.

[0075] For details, see Figure 3 Sensor 700 is a photoelectric sensor. When the edge of wafer 600 passes by, it blocks the detection light of photoelectric sensor 700, triggering it to generate a first trigger signal. When the edge of wafer 600 moves away, it no longer blocks the detection light of photoelectric sensor 700, triggering it to generate a second trigger signal. There are two sensors 700, each with two triggers, allowing the acquisition of four trigger point positions. These trigger point positions correspond to the edge positions of wafer 600 along the detection light. Based on these four trigger point positions, the actual position of the center of wafer 600 can be calculated.

[0076] In one specific embodiment, the actual position of the wafer 600 center is calculated using a least-squares fitting algorithm based on all Cartesian coordinate values, including: for each Cartesian coordinate value ( x i , y i The equation of the circle is: Combining the equations of the circles with all Cartesian coordinates yields a system of linear equations. Transforming this system of linear equations into matrix form provides the final result. A ⋅[D , E , F ] T = b ;Calculate using pseudo-inverse matrix [ D , E , F ]=( A T A ) −1 A T b The actual position of the center of the wafer 600 is obtained as follows: (−D / 2,−E / 2) ;in, D, E, F All are coefficients of the circle equation, ( x i , y i ) is the first i Cartesian coordinates, A For the constructed matrix, b The vector to be constructed.

[0077] In this embodiment, the position of the center of the wafer 600 can be accurately calculated using the least squares fitting algorithm, which can effectively reduce the impact of measurement errors on position accuracy.

[0078] In one specific embodiment, obtaining the correction value based on the eccentric position and the position of station 800 includes: converting the eccentric position of the finger center coordinate system of the robotic arm assembly 510 into the corresponding eccentric position in the coordinate system of station 800; and obtaining the correction value based on the eccentric position in the coordinate system of station 800 and the position of station 800.

[0079] To ensure the accuracy of wafer 600 placement, the robotic arm assembly 510 supports the calculation of wafer 600 eccentricity and the correction of wafer 600 eccentricity during the extension and retraction processes of wafer 600 in different control modes.

[0080] See Figure 5 During the wafer transfer process of the single robotic arm assembly 510, when the robotic arm assembly 510 extends with the wafer 600, the off-center position of the wafer 600 can be calculated, and the single robotic arm assembly 510 can complete the correction action. During the retraction process of the robotic arm assembly 510 with the wafer 600, the off-center position of the wafer 600 can be calculated, and the single robotic arm assembly 510 can complete the correction action.

[0081] See Figure 6During the synchronous wafer transfer process of the multi-robotic arm assembly 510, when at least two robotic arm assemblies 510 are simultaneously extending with wafers 600, the off-center position of each wafer 600 can be calculated simultaneously, and the off-center correction actions of at least two robotic arm assemblies 510 can be completed. Similarly, during the retraction process of at least two robotic arm assemblies 510 with wafers 600, the off-center position of each wafer 600 can be calculated, and the off-center correction actions of at least two robotic arm assemblies 510 can be completed.

[0082] See Figure 7 During the cross-transfer process of the multi-arm assembly 510, at least two arm assemblies 510 can calculate and correct the eccentric position of the corresponding wafer 600 during the cross-extension and retraction action of the wafer 600. The retracted arm assembly 510 can also calculate and correct the eccentric position of the corresponding wafer 600.

[0083] The following explanation uses two robotic arm assemblies 510 as an example to illustrate the wafer-picking process of the unequal-arm independent vacuum robot 500 under different control modes. The joint coordinates of the vacuum robot 500 are [R1,R2,X,Z], where R1 is the telescopic joint position of one robotic arm assembly 510, R2 is the telescopic joint position of the other robotic arm assembly 510, X is the rotational joint position of the vacuum robot 500, and Z is the lifting joint position of the vacuum robot 500.

[0084] See Figure 3 and Figure 5 The motion trajectory of the single robotic arm assembly 510 to retrieve the piece at the selected station 800 (station 800's position coordinates include R = 851260, X = 270069, Z = 66480) is as follows:

[0085] 1) When the single robotic arm component 510 moves to the HOME position, the current coordinates of the vacuum robotic arm 500 are [180000, 180000, 270069, 57480].

[0086] 2) The single robotic arm assembly 510 extends to the selected workstation 800 position, and the current coordinates of the vacuum robotic arm 500 are [851260, 180000, 270069, 57480].

[0087] 3) The vacuum robot 500 moves up and down along the Z-axis to the selected workstation 800. The current coordinates of the vacuum robot 500 are [851260,180000,270069,66480], and the Z-axis is perpendicular to the horizontal plane where the Y-axis is located.

[0088] 4) The single robotic arm component 510 retracts to the HOME position, and the current coordinates of the vacuum robotic arm 500 are [180000, 180000, 270069, 66480].

[0089] See Figure 3 and Figure 6 The motion trajectory of the two robotic arm assemblies 510 simultaneously picking up the piece at the selected station 800 (the coordinates of station 800 include R = 851260, X = 270069, Z = 66480) is as follows:

[0090] 1) The two robotic arm components 510 move to the HOME position, and the current coordinates of the vacuum robotic arm 500 are [180000, 180000, 270069, 57480].

[0091] 2) The two robotic arm assemblies 510 extend to the selected workstation 800 position, and the current coordinates of the vacuum robot 500 are [851260, 851260, 270069, 57480].

[0092] 3) The vacuum robot 500 moves up and down along the Z-axis to the selected workstation 800. The current coordinates of the vacuum robot 500 are [851260, 851260, 270069, 66480].

[0093] 4) The two robotic arm components 510 retract to the HOME position, and the current coordinates of the vacuum robotic arm 500 are [180000, 180000, 270069, 66480].

[0094] See Figure 3 and Figure 7 The motion trajectory of the two robotic arm components 510 to cross-grab the selected workstation 800 (the coordinates of workstation 800 include R = 851260, X = 270069, Z = 66480) is as follows:

[0095] 1) The two robotic arm components 510 move to the HOME position, and the current coordinates of the vacuum robotic arm 500 are [180000, 180000, 270069, 57480].

[0096] 2) One of the robotic arm components 510 extends to the selected workstation 800 position, and the current coordinates of the vacuum robot 500 are [851260, 180000, 270069, 57480].

[0097] 3) The vacuum robot 500 moves up and down along the Z-axis to the selected workstation 800. The current coordinates of the vacuum robot 500 are [851260, 180000, 270069, 66480].

[0098] 4) One robotic arm assembly 510 retracts to HOME, and the other robotic arm assembly 510 extends to workstation 800. The current coordinates of the vacuum robot 500 are [180000, 851260, 270069, 66480].

[0099] 5) The two robotic arm components 510 retract to the HOME position, and the current coordinates of the vacuum robotic arm 500 are [180000, 180000, 270069, 66480].

[0100] In the description of this invention, it should be understood that the terms “comprising” and “having” as used herein, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0101] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0102] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0103] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the present invention. Furthermore, the present invention described herein may have other embodiments and can be implemented or carried out in various ways. Unless otherwise defined, the technical or scientific terms used herein should be understood in their ordinary sense by one of ordinary skill in the art to which this invention pertains.

Claims

1. A control method for an unequal-arm independent vacuum manipulator, characterized in that, The vacuum manipulator (500) includes N robotic arm assemblies (510), a lifting motor, a rotary motor, and N telescopic motors. The lifting motors drive all the robotic arm assemblies (510) to lift synchronously, the rotary motors drive all the robotic arm assemblies (510) to rotate synchronously, and the telescopic motors are configured one-to-one with each robotic arm assembly (510) and are used to drive the corresponding robotic arm assembly (510) to extend or retract. Here, N is a positive integer greater than 1. The control method includes: S1: The vacuum robot (500) selects the corresponding control mode according to the instructions sent by the host computer and in combination with the position of the taught workstation (800). The control mode includes single pick-up and single place, multiple pick-up and multiple place and cross pick-up and place. S2: Based on the selected control mode and the position of the workstation (800), the motion trajectory is planned; S3: By transforming the joint coordinate system and the motor coordinate system of the robot arm through forward or backward kinematics algorithms, the motion trajectory is decoupled from the position point. S4: The vacuum manipulator (500) transports the wafer (600) according to the decoupled position point and the motion trajectory. The transformation between the robot joint coordinate system and the motor coordinate system includes: the transformation between the polar coordinate system of the robot joint and the coordinate system of the lifting motor, the transformation between the polar coordinate system of the robot joint and the coordinate system of the rotary motor, and the transformation between the polar coordinate system of the robot joint and the coordinate system of the telescopic motor. The joint coordinates of the vacuum manipulator (500) are defined as [R1, ... R2]. N The motor coordinates are defined as [Tz, T1, ..., Tz]. N [,To], where R1, ..., R N Let X be the telescopic joint position of the first to the Nth robotic arm assembly (510), Z be the rotational joint position of the vacuum manipulator (500), Tz be the lifting joint position of the vacuum manipulator (500), and T1, ..., T2 be the encoder value of the lifting motor. N These are the encoder values ​​for the first to the Nth telescopic motors, respectively, and To is the encoder value for the rotary motor; Step S3 includes: the rotational joint position X of the vacuum manipulator (500) is converted to correspondence with the encoder value To of the rotary motor; the lifting joint position Z of the vacuum manipulator (500) is converted to correspondence with the encoder value Tz of the lifting motor; and the telescopic joint position R of the robotic arm assembly (510) is converted to correspondence with the encoder value T of the telescopic motor through a forward or reverse kinematics algorithm. The forward kinematics algorithm uses the following formula: ； ； get ; The inverse kinematics algorithm uses the following formula: ； ； get ; The robotic arm assembly (510) includes a first arm (511) and a second arm (512). The telescopic motor drives the first arm (511) to rotate, thereby driving the second arm (512) to rotate. L1 is the effective length of the first arm (511), L2 is the effective length of the second arm (512), D is the length difference between the first arm (511) and the second arm (512) in the Y-axis direction, θ1 is the angle between the first arm (511) and the Y-axis direction, θ2 is the angle between the second arm (512) and the Y-axis direction, and R is the telescopic joint position of the robotic arm assembly (510).

2. The control method for the unequal-arm independent vacuum manipulator according to claim 1, characterized in that, The corresponding encoder value T of the telescopic motor is obtained by converting the angle θ1 between the first arm (511) and the Y-axis direction, so that the telescopic motor can drive the robotic arm assembly (510) to realize the telescopic adjustment of the telescopic joint position R of the robotic arm assembly (510) according to the encoder value T of the telescopic motor.

3. The control method for the unequal-arm independent vacuum manipulator according to claim 1, characterized in that, At least two sensors (700) are provided on the conveying path of the robotic arm assembly (510) for each workstation (800). During the process of the robotic arm assembly (510) transferring the wafer (600), the actual position of the center of the wafer (600) is detected and calculated by the sensor (700), and then it is determined whether the wafer (600) is eccentric. If the wafer (600) is eccentric, the eccentric position of the wafer (600) is calculated, and the correction value is obtained according to the eccentric position and the position of the work station (800). The correction value is used to correct the position of the wafer (600).

4. The control method for the unequal-arm independent vacuum manipulator according to claim 3, characterized in that, The actual position of the center of the wafer (600) is detected and calculated by the sensor (700), including: When the edge of the wafer (600) passes the sensor (700), the trigger point position corresponding to each trigger is obtained, and all the trigger point positions are converted into corresponding Cartesian coordinate values ​​through a forward kinematics algorithm; The actual position of the center of the wafer (600) is calculated using a least-squares fitting algorithm based on all the Cartesian coordinate values.

5. The control method for the unequal-arm independent vacuum manipulator according to claim 4, characterized in that, Based on all the Cartesian coordinate values, the actual position of the center of the wafer (600) is calculated using a least-squares fitting algorithm, including: For each of the Cartesian coordinate values ​​( x i , y i The equation of the circle is: ; Combining the circle equations of all the Cartesian coordinate values ​​yields a system of linear equations. Transforming this system of linear equations into matrix form yields... A ⋅[ D , E , F ] T = b ; Calculate using the pseudo-inverse matrix [ D , E , F ]=( A T A ) −1 A T b The actual position of the center of the wafer (600) is obtained as follows: (−D / 2,− E / 2) ; in, D, E, F All are coefficients of the circle equation, ( x i , y i ) is the first i Cartesian coordinates, A For the constructed matrix, b The vector to be constructed.

6. The control method for the unequal-arm independent vacuum manipulator according to claim 3, characterized in that, The correction value is obtained based on the eccentric position and the workstation (800) position, including: The eccentric position of the finger center coordinate system of the robotic arm assembly (510) is converted into the eccentric position of the corresponding workstation (800) coordinate system; The correction value is obtained based on the eccentric position in the coordinate system of the workstation (800) and the position of the workstation (800).

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