A kind of two freedom space parallel mechanism
(1) technical field
The invention belongs to robot and mechanical manufacturing field, be specifically related to a kind of two freedom space parallel mechanism.
(2) background technology
In recent years, spatial parallel device people has caused the extensive interest of Chinese scholars, with serial machine physiognomy ratio, parallel robot has that rigidity is big, load is from the anharmonic ratio height, characteristics such as site error does not accumulate are used widely under multi-freedom robot design, NC machining, high-mechanic strength condition.Space six-degree-of-freedom parallel robot the earliest is based on the 6-SPS mechanism that Stewart proposed in nineteen sixty-five.The version of horn of plenty and development parallel robot, the scholar of many research institutions begins useful work.Six-degree-of-freedom parallel robot mechanism is ideal mechanism, but the existence of this type mechanism is little as working space; Shortcomings such as flexibility is not high, forward kinematics solution does not seal, dimension synthesis difficulty, and manufacturing cost height.Compare with six-degree-of-freedom parallel connection mechanism, therefore advantage such as that the lower-mobility parallel institution has is simple in structure, working space is big, design and control are fairly simple has proposed cheap, the simple various lower-mobility parallel robots of use in the development of robot.
In the design process of articulated robot, the multi-freedom joint structural design is an important step, and in traditional cascaded structure, its multi-freedom joint rotating shaft is difficult to meet at a bit; Promptly enable to meet at a bit, the volume weight in its joint all increases greatly.And by adopting the lower-mobility parallel institution to replace the series connection form, then be designed to the multi-freedom joint rotating shaft easily and meet at a bit.The parallel institution that rotates based on Three Degree Of Freedom in the existing directed parallel institution, the parallel institution that proposed in 1993 as Hayward, the parallel institution that Cheng proposed in nineteen ninety-five etc.And the parallel institution of realizing the two-dimensional space directed movement is less, a kind of two degrees of freedom rotating parallel robot mechanism as the patent No. 200310115537.4, but its volume is big, practicality is relatively poor, is difficult to adapt to the mechanical arm or the pedipulator design of little multi-freedom joint.Existing majority and freedom degree parallel connection mechanism is mainly realized the two dimensional surface setting movement is a kind of two-degrees-of-freedom translation parallel robot mechanism of 01277647.5 as the patent No..
In sum, the parallel institution of the two-dimensional space directed movement of realization small size is less at present, need one of design to have that the working space scope is big, volume is relative with weight less, be convenient to the two freedom space parallel mechanism of the control of mechanism simultaneously, will be used widely at aspects such as multi freedom degree mechanical arm or pedipulators, have important practicability and be worth.
(3) summary of the invention
The object of the present invention is to provide a kind of can around some rotations have that the operation angular space is big, volume is little, rigidity is strong, precision is high, motion mode is clear and definite, the positive and negative two-dimentional directional space parallel institution of separating characteristics such as simple of kinematics.
The object of the present invention is achieved like this: it comprises fixed platform, moving platform and is connected fixed platform and the branch of moving platform that described connection fixed platform and moving platform branch have 3; Moving platform is provided with two kinematic pairs, wherein the structure of two branches is identical, and they all comprise sliding bar and connecting rod, and sliding bar links to each other with moving platform by kinematic pair, one end of connecting rod and an end of sliding bar are connected by kinematic pair, and the other end of connecting rod is connected by kinematic pair with fixed platform; Another branch comprises two vertical rods, and an end of a vertical rod is connected with fixed platform and is vertical with fixed platform, and an end of another root vertical rod is connected with moving platform and is vertical with moving platform, connects by hook hinge between two vertical rods.
The present invention can also comprise some architectural features like this:
1, the kinematic pair on the described moving platform is a moving sets, and the kinematic pair between described connecting rod and the sliding bar is a spherical pair, and the kinematic pair between described connecting rod and the fixed platform is a spherical pair.
2, the kinematic pair on the described moving platform is a moving sets, and the kinematic pair between described connecting rod and the sliding bar is a spherical pair, and the kinematic pair between described connecting rod and the fixed platform is a hook hinge.
3, the kinematic pair on the described moving platform is a moving sets, and the kinematic pair between described connecting rod and the sliding bar is a hook hinge, and the kinematic pair between described connecting rod and the fixed platform is a spherical pair.
4, the kinematic pair on the described moving platform is a cylindrical pair, and the kinematic pair between described connecting rod and the sliding bar is a spherical pair, and the kinematic pair between described connecting rod and the fixed platform is a spherical pair.
5, the kinematic pair on the described moving platform is a cylindrical pair, and the kinematic pair between described connecting rod and the sliding bar is a spherical pair, and the kinematic pair between described connecting rod and the fixed platform is a hook hinge.
6, the kinematic pair on the described moving platform is in cylindrical pair, and the kinematic pair between described connecting rod and the sliding bar is a hook hinge, and the kinematic pair between described connecting rod and the fixed platform is a spherical pair.
Operation principle of the present invention is: by sliding bar with respect to the moving of the moving sets direction of moving platform, drivening rod realizes that the two degrees of freedom spatial orientation of hook hinge between moving platform and the fixed platform rotates.
Useful advantage of the present invention has:
1, parallel institution of the present invention can be realized directed rotation of two dimension around a bit;
2, parallel institution kinematics of the present invention is positive and negative separates simply;
3, the divertical motion of parallel institution of the present invention rotates by the orientation of the telescopic moving realization both direction of sliding bar, has certain rigidity and kinematic accuracy;
4, parallel institution of the present invention has higher load capacity than the series connection Two-Degree-of-Freedom mechanism, compares other two-freedom-degree parallel mechanisms and has smaller volume;
5, parallel institution of the present invention has important wide application prospect in the operation that needs the two degrees of freedom spatial movement.
(4) description of drawings
Fig. 1 is the structural scheme of mechanism of first kind of embodiment of the present invention;
Fig. 2 is the structural scheme of mechanism of second kind of embodiment of the present invention;
Fig. 3 is the structural scheme of mechanism of the third embodiment of the present invention;
Fig. 4 is the structural scheme of mechanism of the 4th kind of embodiment of the present invention;
Fig. 5 is the structural scheme of mechanism of the 5th kind of embodiment of the present invention;
Fig. 6 is the structural scheme of mechanism of the 6th kind of embodiment of the present invention;
Fig. 7 is the left view of first kind of embodiment of the present invention;
Fig. 8 is the front view of first kind of embodiment of the present invention;
Fig. 9 is the right view of first kind of embodiment of the present invention.
(5) specific embodiment
Below in conjunction with the drawings and specific embodiments the present invention is described in further detail:
Embodiment 1:
In conjunction with Fig. 1, present embodiment comprises fixed platform 1, hook hinge 2, moving platform 3, sliding bar 4 and 5, moving sets 6 and 9, connecting rod 8 and 11 and spherical pair 6,10,12,13, vertical rod 14 and 15, moving platform 3 is provided with two moving sets 6 and 9, and is connected with fixed platform 1 by three branches; Wherein two branched structures are identical in three branches, a branch of two identical structure branches comprises a sliding bar 4 and a connecting rod 8, sliding bar 4 is connected by moving sets 6 with moving platform 3,4 one of 8 one on connecting rod and sliding bars are connected by spherical pair 7, and the other end of connecting rod 8 is connected by spherical pair 13 with fixed platform 1; Another branch of two identical structure branches comprises a sliding bar 5 and a connecting rod 11, sliding bar 5 is connected by moving sets 9 with moving platform 3,5 one of 11 1 on connecting rod and sliding bars are connected by spherical pair 10, and the other end of connecting rod 11 is connected by spherical pair 12 with fixed platform 1; The 3rd branch comprises vertical rod 14 and 15, vertical rod 14 1 ends are connected with fixed platform 1 and keep vertical with fixed platform 1, vertical rod 15 1 ends are connected with moving platform 3 and keep vertical with moving platform 3, and the other end of vertical rod 14 is connected by hook hinge 2 with vertical rod 15 other ends.
If during mechanism's original state, moving platform 3 is parallel and vertical with the Z axle of position fixing system with fixed platform 1, two rotating shafts of hook hinge 2 are parallel with Y-axis with the X-axis of position fixing system respectively, moving sets 6 is parallel with the Z axle of position fixing system with 9 axis, and the branch of two same structures is with respect to distributing through hook hinge 2 central points and the plane symmetry that is parallel to the YOZ plane.
Embodiment 2:
In conjunction with Fig. 2, present embodiment with the connecting rod among the embodiment 18 and 11 with fixed platform 1 between the spherical pair 12 and 13 that is connected change hook hinge 17 and 16 into, other structure is identical with embodiment 1.
Embodiment 3:
In conjunction with Fig. 3, present embodiment with the connecting rod among the embodiment 18 and 11 with sliding bar 4 and 5 between the spherical pair 7 and 10 that is connected change hook hinge 18 and 19 into, other structure is identical with embodiment 1.
Embodiment 4:
In conjunction with Fig. 4, present embodiment changes the moving sets 6 and 9 that is connected between the moving platform among the embodiment 13 and sliding bar 4 and 5 into cylindrical pair 20 and 21, and other structure is identical with embodiment 1.
Embodiment 5:
In conjunction with Fig. 5, present embodiment changes the moving sets 6 and 9 that is connected between the moving platform among the embodiment 23 and sliding bar 4 and 5 into cylindrical pair 20 and 21, and other structure is identical with embodiment 2.
Embodiment 6:
In conjunction with Fig. 6, present embodiment changes the moving sets 6 and 9 that is connected between the moving platform among the embodiment 33 and sliding bar 4 and 5 into cylindrical pair 20 and 21, and other structure is identical with embodiment 3.