CN-121989206-A - Five-axis robot configuration comprehensive method integrating 2R1T parallel mechanism

Abstract

The invention discloses a five-axis robot configuration comprehensive method integrating 2R1T parallel mechanisms, which belongs to the technical field of manufacturing robots, wherein a two-rotation one-translation (2R 1T) parallel mechanism is a core functional module of the five-axis robot, most 2R1T parallel mechanisms are parallel mechanisms formed by connecting a plurality of kinematic pairs (such as an R pair, an S pair, a P pair, a U pair and a C pair) in series to form a motion branched chain, two ends of the motion branched chain are respectively connected with a static platform and a movable platform, and calculation is performed based on a PRU (partial pressure unit) -based motion branched chain.

Inventors

• FANG HANLIANG
• Lu Miaoming
• HE ZHEN
• ZHANG JUN
• NIE YUZHE

Assignees

• 福州大学

Dates

Publication Date

20260508

Application Date

20260123

Claims (5)

1. 1. A five-axis robot configuration comprehensive method integrating a 2R1T parallel mechanism is characterized by comprising the following steps: For the 2R1T parallel mechanism, selecting a PRU type motion branched chain to carry out comprehensive configuration research of the 2R1T parallel mechanism, wherein the PRU type motion branched chain refers to a type of motion branched chain with a configuration of PUR, PRU, UPR, URP, RPU, RUP, P represents a moving pair, R represents a revolute pair and U represents a Hooke joint; Step two, synthesizing a series of potential configurations by a 2R1T parallel mechanism formed by a PRU moving branched chain, classifying the potential configurations of the 2R1T parallel mechanism into three types including UP, PU, RPR types according to the distribution positions of the rotating shafts; Step three, aiming at the specific functions to be realized by the five-axis robot, arranging a 2R1T parallel mechanism and a single-degree-of-freedom joint module, selecting corresponding different types of configurations for combination, and obtaining a configuration comprehensive result; And step four, selecting corresponding combinations in the configuration comprehensive result according to the actual working requirements of the five-axis robot to obtain the configuration design of the five-axis robot of the 2R1T parallel mechanism.
2. 2. The method for integrating the configuration of the 2R1T parallel mechanism with the five-axis robot of claim 1, wherein in the first step, for the 2R1T parallel mechanism, a calculation process for selecting a 'PRU' type movement branched chain to calculate the configuration of the 2R1T parallel mechanism is specifically as follows: According to the spin theory, a PRU type motion branched chain motion spin system is obtained: ; In the above-mentioned method, the step of, 、 、 、 Respectively represent the axis of the movable auxiliary joint, the axis of the revolute auxiliary joint and the axis of the Hooke's joint ; 、 、 、 Respectively representing the unit direction vectors at the two joint axes of the mobile auxiliary joint axis, the revolute auxiliary joint axis and the Hooke joint axis, And The position vectors respectively representing the geometric centers of the rotary joint and the hook joint, the vectors and the rotation are measured under a branched chain coordinate system, and the motion screw is reversely screwed to obtain the constraint rotation system as follows: ; In the above-mentioned method, the step of, Representing a plane perpendicular to And Is a constraint couple rotation amount; Representing an excess At any point along the axis and parallel to Is limited by the constraint force rotation of the rod; Is expressed by The method comprises the steps of positioning a position vector of any point of an axis, constructing a redundant driving parallel operation head by utilizing a motion branched chain with less degrees of freedom, and ensuring that the constraint rotation introduced by a new branched chain is linearly related to an original constraint rotation system by ascertaining the geometric condition of equivalent constraint between two motion branched chains, so that when the constraint rotation of the two motion branched chains and the constraint force couple rotation are equal according to the rotation theory, the constraint rotation of the two PRU-type motion branched chains meets the following formula: ; In the above-mentioned method, the step of, A constraint force couple rotation denoted as a first "PRU" motion branch, A constraint force couple rotation denoted as a second "PRU" motion branch, Represented as a unit direction vector at the first joint of the first "PRU" motion branch hook hinge, Expressed as a unit direction vector at the second joint of the first "PRU" motion branch hook hinge, Expressed as a unit direction vector at the first joint of the second "PRU" motion branch hook hinge, Represented as a unit directional vector at the second joint of the second "PRU" kinematic branched hooke's joint, The binding force spin denoted as the first "PRU" motion branch, The binding force rotation denoted as the second "PRU" motion branch, A unit direction vector denoted as a first "PRU" kinematic branched revolute pair, Represented as too much A position vector at any point of the axis, A unit direction vector denoted as a second "PRU" kinematic branched revolute pair, Represented as too much The position vector of any point of the axis is deduced as follows: ; According to the above, the geometry for realizing equal constraint force couple rotation and constraint force rotation between two PRU-type motion branched chains is expressed as follows And Parallel to each other, and a second axis of the Hooke's joint in the two branched chains And Collinear, two "PRU" kinematic branches arranged to satisfy the geometric condition are referred to as a 2'PRU' mechanism, the constraint rotations of which are as follows: ; In the above-mentioned method, the step of, 、 Respectively represent the 1 st and 2 nd constraint rotations of the 2'PRU' mechanism, And A unit direction vector representing a first axis and a second axis of the hook hinge; A unit direction vector representing the axis of the revolute pair; And (3) representing the position vector of any point on the second axis of the Hooke hinge, and then carrying out reverse spiral to obtain a motion spiral system of the 2'PRU' mechanism: ; In the above-mentioned method, the step of, 、 、 And From the above analysis, it is clear that the single 2'PRU' mechanism has generated a restraining force and a restraining couple, the 2R1T mechanism has two degrees of rotational freedom and one degree of freedom of movement, so that the movement branches except the 2'PRU' mechanism can only generate a restraining force, and from the 2RU mechanism movement rotation system, the 2'PRU' mechanism loses its restraining couple after introducing a zero pitch movement rotation which is not coplanar with the two axes of the hook hinge, the mechanism is called a (2 'PRU') R mechanism, therefore, there will be only a restraining force in the (2 'PRU') R mechanism, an additional revolute pair is introduced at the end of the 2'PRU' mechanism, the axis of the revolute pair is perpendicular to and intersects the second axis of the hook hinge in the "PRU" movement branch, and the introduced revolute pair movement rotation is expressed as follows: ; In the above-mentioned method, the step of, A unit direction vector representing the new revolute pair; the position vector representing the intersection point of the new revolute pair axis and the Hooke's hinge second axis is obtained, and the formula of the motion rotation system of the (2 ' PRU ') R mechanism is as follows: ; the motion rotation system of the (2 'PRU') R mechanism is reversely spiraled to obtain the constraint spiral system of the (2 'PRU') R mechanism: ; The maximum linear independent constraint rotation of the parallel mechanism consisting of the 2'pru' mechanism and the (2 'pru') R mechanism is thus obtained as: ; In the above-mentioned method, the step of, 、 、 Respectively represent the 1 st, 2 nd and 3 rd independent constraint rotations, 、 And Unit direction vectors respectively representing a revolute pair axis, a hook first axis and a hook second axis of the 2'PRU' mechanism; the unit direction vector of the axis of the revolute pair of the (2 'PRU') R mechanism is represented, and then the inverse screw solution is carried out on the maximum linear independent constraint screw system to obtain the motion screw of the parallel mechanism: ; In the above-mentioned method, the step of, Representing a degree of freedom of movement, perpendicular to And ; Representing a degree of freedom of rotation, the axis of rotation being parallel to And passes through point O; Representing a degree of freedom of rotation, the axis of rotation being parallel to And the movement rotation of the parallel mechanism through the point O shows that the 2'PRU' mechanism and the (2 'PRU') R mechanism form a 2R1T parallel mechanism, the 2R1T parallel mechanism is provided with two rotating shafts, one rotating shaft is close to the Hooke hinge of the 2'PRU' mechanism, and the other rotating shaft is close to the Hooke hinge of the (2 'PRU') R mechanism, so that a plurality of 2R1T parallel mechanisms are calculated.
3. 3. The method for integrating the configuration of the 2R1T parallel mechanism with the five-axis robot is characterized in that in the second step, the configuration of the 2R1T parallel mechanism is classified according to the distribution positions of the rotation axes, the UP type rotation axes are close to the static platform, the PU type rotation axes are close to the movable platform, the RPR type rotation axis is close to the static platform, and the RPR type rotation axis is close to the movable platform.
4. 4. The method for integrating the configuration of the 2R1T parallel mechanism five-axis robot according to claim 3, wherein in the third step, aiming at the functions to be realized by the five-axis robot, the types of the 2R1T parallel mechanism and the single-degree-of-freedom joint module comprise the following steps: The 2R1T parallel mechanism is divided into three types according to functions in the five-axis robot, wherein the three types comprise two-position adjustment, one-position adjustment, two-position adjustment and three-position adjustment, and the functions of the serial single-degree-of-freedom joint module in the five-axis robot are divided into two-position adjustment, one-position adjustment and two-position adjustment according to different functions of the 2R1T parallel mechanism.
5. 5. The method for integrating the five-axis robot configuration of the 2R1T parallel mechanism according to claim 4, wherein in the third step, the configurations corresponding to different types are selected for combination, and the topology configuration of the five-axis robot is divided into the following three combinations: The two rotating shafts of the 2R1T parallel mechanism are both close to the movable platform, the 2R1T parallel mechanism has the functions of 1 position adjustment and 2 gesture adjustment, and 2 single-degree-of-freedom joint modules for position adjustment are required to be connected in series, wherein the configuration is defined as a double-position adjustment type, and corresponds to a PU type in the configuration of the 2R1T parallel mechanism; Two rotating shaft positions of the 2R1T parallel mechanism are close to the static platform, the 2R1T parallel mechanism has a function of 3 position adjustment, 2 single-degree-of-freedom joint modules for gesture adjustment are required to be connected in series, the configuration is defined as a double gesture adjustment type, and the UP type in the configuration of the 2R1T parallel mechanism corresponds to the configuration of the 2R1T parallel mechanism; And in the third condition, one rotating shaft of the 2R1T parallel mechanism is close to the movable platform, the other rotating shaft is close to the static platform, the 2R1T parallel mechanism is in 2-position-adjusting and 1-gesture-adjusting mode, 1 single-degree-of-freedom joint module for position adjustment and 1 single-degree-of-freedom joint module for gesture adjustment are required to be connected in series, the configuration is defined as gesture-adjusting and gesture-adjusting mode, the RPR mode in the 2R1T parallel mechanism configuration corresponds to the RPR mode, and different combinations are selected according to the condition to realize the function corresponding to the requirement.

Description

Five-axis robot configuration comprehensive method integrating 2R1T parallel mechanism Technical Field The invention relates to the technical field of robot configuration, in particular to a five-axis robot configuration comprehensive method integrating a 2R1T parallel mechanism. Background The five-axis robot combines the advantages of high stability, high rigidity, high speed and the like of a parallel mechanism and the advantage of expanding working space of a serial mechanism, so that the application potential of the five-axis robot in high-efficiency processing of large complex structural members is further expanded, wherein the 2R1T parallel mechanism is a three-degree-of-freedom parallel mechanism with one degree of freedom of movement and two degrees of freedom of rotation, and the five-axis parallel-serial processing robot has the advantages of high rigidity, high load capacity, high motion precision and the like, and the successful commercial five-axis parallel-serial processing robots Eco-speed, tricept and Exechon all adopt the 2R1T parallel mechanism as core function modules. The configuration of the five-axis robot is comprehensive, one is the design of a parallel mechanism, the other is the selection and matching of a single-degree-of-freedom joint module and the parallel mechanism which are connected in series, and the two are indispensable. At present, most students only study the configuration comprehensive method of the 2R1T parallel mechanism, the selection of the serial single-degree-of-freedom joint modules is not involved, and the whole configuration design process of the five-axis robot cannot be guided. The motion performance of the five-axis robot is highly dependent on configuration matching and space layout of modules of the serial-parallel mechanism, the single-degree-of-freedom joint module of the five-axis robot supplements the motion capability of the 2R1T parallel mechanism, and the five-axis robot with good motion performance is formed together, and if the single-degree-of-freedom joint module is improperly selected, the working space of the five-axis robot is smaller, so that the expected motion performance of the five-axis robot cannot be achieved. However, the research on the configuration comprehensive method of the whole five-axis robot is still relatively lacking at present, only a few scholars perform research, such as Yundou Xu performs type synthesis and motion decoupling on a 2R1T parallel mechanism, and a five-axis robot construction principle is provided based on the motion decoupling, but a complete five-axis robot configuration selection scheme is not mentioned. Disclosure of Invention The invention aims to provide a five-axis robot configuration comprehensive method integrating a 2R1T parallel mechanism, which obtains a series of 2R1T parallel mechanism topological configurations through a spiral theory, analyzes a 2R1T parallel mechanism movement spiral system, reasonably configures the 2R1T parallel mechanism and a single-degree-of-freedom joint module, and ensures that the five-axis robot can have the required movement performance. In order to achieve the above purpose, the invention provides a five-axis robot configuration comprehensive method integrating a 2R1T parallel mechanism, which comprises the following steps: For the 2R1T parallel mechanism, selecting a PRU type motion branched chain to carry out comprehensive configuration research of the 2R1T parallel mechanism, wherein the PRU type motion branched chain refers to a type of motion branched chain with a configuration of PUR, PRU, UPR, URP, RPU, RUP, P represents a moving pair, R represents a revolute pair and U represents a Hooke joint; Step two, synthesizing a series of potential configurations by a 2R1T parallel mechanism formed by a PRU moving branched chain, classifying the potential configurations of the 2R1T parallel mechanism into three types including UP, PU, RPR types according to the distribution positions of the rotating shafts; Step three, aiming at the specific functions to be realized by the five-axis robot, arranging a 2R1T parallel mechanism and a single-degree-of-freedom joint module, selecting corresponding different types of configurations for combination, and obtaining a configuration comprehensive result; And step four, selecting corresponding combinations in the configuration comprehensive result according to the actual working requirements of the five-axis robot to obtain the configuration design of the five-axis robot of the 2R1T parallel mechanism. Preferably, in the first step, for the 2R1T parallel mechanism, the calculation process of selecting the "PRU" type motion branch to calculate the configuration of the 2R1T parallel mechanism is specifically as follows: According to the spin theory, a PRU type motion branched chain motion spin system is obtained: ; In the above-mentioned method, the step of, 、、、Respectively represent the axis of the movable auxiliary joint, th