A kind of flexible unit for industrial robot Fine Boring and flexible waist
Technical field
The utility model relates to mechanical wrist, particularly relates to a kind of the industrial robot flexible unit and the flexible waist that industrial robot Fine Boring are carried out to rigging error compensation.
Background technology
In robot automation's assembling work, due to repeatability positioning precision error, the frock clamp tolerance and parts machining tolerance etc. of robot and material conveying system, rigging error (comprising linear displacement direction and angle direction) is had between parts to be assembled, and the assembly precision between parts generally to be assembled requires higher, particularly require the field of Fine Boring at 3C (computer and communication electronic equipment for consumption) etc., thus cause robot to complete fittage.Therefore, robot automation's Fine Boring system must comprise the device eliminating rigging error.
Rigging error is eliminated by the mode of the motion and machining accuracy that improve robot, material conveying system, frock clamp, parts etc., but the method significantly will improve the cost of robot Fine Boring system, is not suitable for the commercial Application of large-scale low-cost.Current existing solution has two kinds: one to be the mode adopting visual servo or force feedback etc. initiatively to eliminate, but the servo control loop that this mode needs vision sensor or force snesor, controller etc. to form and relevant software systems, will cause the rising of robotic assembly system's cost; Another kind method adopts flexible waist for robot to eliminate rigging error passively, this kind of solution is without the need to using sensor and controller etc., when parts Contact to be assembled, flexible waist compensates rigging error fast by the elastic deformation of self flexible portion, is a kind of rigging error compensation arrangement of simple low cost.
Traditional rigid machine human wrist is connected and composed by positive drive mechanisms such as spherical gear, bevel gear combinations usually, can under the driving of multiple driver, adjustment locus and attitude.But limit by frame for movement, kinematic dexterity is poor, number of degrees of freedom, is also less, can not be applicable to Fine Boring operation, only can complete the operations such as carrying, loading and unloading.
Flexible waist for robot is the parts connecting robot arm and the end effector such as manipulator or fixture, it can utilize the elastic deformation of self flexible structure to change the spatial attitude of end effector and position to eliminate the rigging error in all directions, completes robotic asssembly task.
Flexible waist for robot has a flexible central be positioned at outside its device, and the design of this flexible central is being positioned at the contact position between parts to be assembled.For peg-in-hole assembly, this flexible central is designed in rod member end to be assembled.At this flexible central place, the displacement that applying horizontal force only can produce the horizontal displacement in this horizontal direction and not produce on other direction, the displacement that applying moment of torsion only can produce the angle displacement in this torque direction and not produce on other direction.Setting forth from stiffness matrix aspect is then that, at this flexible central point place, the stiffness matrix of flexible waist device is diagonal angle, namely without the coupling on any direction.Therefore, the new rigging error can not introduced on other direction is adopted in the process of the rigging error of the robot of flexible waist in elimination a direction.
Flexible waist for robot is the earliest made up of two kinds of flexible unit usually.Wherein a kind of flexible unit is used to provide the rigging error compensation of linear displacement, and the rigging error that another kind is used to provide on angle direction compensates.The design that this kind is made up of two kinds of flexible unit, structure is comparatively complicated.In addition, the version of flexible unit is generally the round bar having flexible hinge at end, and this kind of structural stress is comparatively concentrated, causes the performance of flexible waist device fatigue poor.Therefore, this kind of design does not have industrially large-scale application.
Afterwards, flexible waist is had to adopt the integrated flexible unit closed, but the integrated flexible rigidity closed is larger, the rigging error that can compensate under fixing insertion force is limited, and the replaceable part flexible unit of discrete flexible unit of comparing, the flexible unit of integration can only all be changed, and maintenance cost is high.
Also have partially flexible wrist design to adopt the single flexible unit of discrete distribution, the rigging error that can be simultaneously provided on linear displacement and angle direction compensates.This single flexible unit adopts the composite construction of standardized helical spring or a kind of metal and rubber to form usually.But the flexible waist for robot become by Coiled Spring Design has following deficiency: because helical spring structure form is fixed, the flexible central position of the flexible waist device formed with it is limited, linear displacement and angular error compensation ability are also very limited in addition, therefore, industrially large-scale application is difficult to.Part adopts helical spring design only can realize position on three degree of freedom direction and pose adjustment, only can compensate the rigging error (if publication number is the patent document of CN101863035A, CN101863035B, CN201824359U) on three degree of freedom direction.Mostly the design of present industrial application is to adopt the flexible unit formed with the composite construction of metal and rubber to design.But the composite structure of metal and rubber also has following deficiency: first processed complex, processing cost is higher, is difficult to large-scale industrial application.Secondly, this kind of structure only can allow elastic deformation among a small circle, because moderate finite deformation can make rubber layer occur tired and tear.
Utility model content
In order to overcome the deficiencies in the prior art, one of the purpose of this utility model is to provide a kind of flexible unit for industrial robot Fine Boring, larger plastic deformation can be provided in linear displacement and angle direction, thus the large linear displacement of compensate for slower and angular compliance error, and with low cost, high life.
Two of the purpose of this utility model is to provide a kind of flexible waist for industrial robot Fine Boring, can effectively realize rigging error and compensate on the basis of with low cost, high life.
One of the purpose of this utility model realizes by the following technical solutions:
For a flexible unit for industrial robot Fine Boring, comprise the flexible body of strip, the sidepiece of this flexible body has multiple grooving, and each grooving is spaced apart along the length direction of flexible body.
Preferably, grooving is interspersed in the relative both sides of flexible body.
Preferably, the spacing of adjacent cutback is equal, and the groove width of each grooving is equal, and the groove depth of each grooving is equal.
Preferably, the groove width of each grooving is increased by the two ends of flexible body gradually to the center of flexible body or reduces gradually.
Preferably, flexible body is prismatic cylinder, and the cross section of this flexible body is circular or regular polygon.
Two of the purpose of this utility model realizes by the following technical solutions:
Adopt a kind of flexible waist for industrial robot Fine Boring of described flexible unit, comprise active plate, follower plate and at least two described flexible unit, active plate and follower plate are parallel to each other and spaced, two ends difference affixed active plate and the follower plate removably of flexible unit, each flexible unit distributes about the central axis axial symmetry of active plate.
Preferably, each flexible unit and place, active plate affixed one end diameter of a circle are greater than place, the affixed one end diameter of a circle with follower plate.
Preferably, active plate and follower plate have the installing hole of multiple circumferentially array distribution, are provided with mounting platform in installing hole, and the two ends of flexible unit to be plugged in installing hole and respectively respectively by screw lock in mounting platform.
Preferably, described flexible waist also comprises gag lever post, and active plate and follower plate have the spacing hole of multiple circumferentially array distribution, one end of gag lever post and the spacing hole of active plate affixed, the other end of gag lever post is less than the spacing hole of follower plate.
Preferably, described flexible waist also comprises retaining mechanism, this retaining mechanism has fixed part and is stretched out by fixed part and make the tight lock part of expanding-contracting action, wherein: fixed part is fixed on active plate, tight lock part switches between the position that retraction departs from follower plate and stretches out locking follower plate, or fixed part is fixed on follower plate, tight lock part switches between the position that retraction departs from active plate and stretches out locking active plate.
Compared to existing technology, the beneficial effects of the utility model are:
Flexible unit of the present utility model, then high-precision grooving can be obtained by techniques such as Linear cut, after each grooving is formed, linear displacement and the larger plastic deformation ability of torsional direction can be obtained, thus the large linear displacement of compensate for slower and angular compliance error, more crucially be, just plastic deformation ability can be obtained by cutting formation grooving earnestly to flexible body, and, the quantity of grooving, bearing of trend, width, the degree of depth, spacing can need flexible modulation according to design, design variable is more, expand the design domain of flexible unit, compare as the flexible waist of flexible unit with similar employing metal-rubber composite construction, flexible unit in the utility model adopts single material, processing method is simple, reduce processing and manufacturing cost, and high life,
Flexible waist of the present utility model, without the need to driver, sensor, the exterior operator such as controller and control software design, passively can carry out compensating error by the distortion of self flexible unit, can with low cost, the basis of high life effectively realizes rigging error to compensate, particularly in conjunction with more than three flexible unit, the rigging error that just can realize flexible waist 6 frees degree compensates, and, the axial symmetry distribution of flexible unit, define the flexible waist of rotational symmetry, the discrete distribution of this flexible unit, so that after certain flexible unit is damaged, impaired flexible unit can be changed separately, without the need to whole replacing, be beneficial to further and reduce costs,
Flexible waist of the present utility model can also as a kind of universal standard part, by active plate and follower plate, all can realize Fast Installation fix, without the need to transforming existing machinery equipment with the top installed surface of existing mechanical arm tail end installed surface and manipulator.
Accompanying drawing explanation
Fig. 1 is the structural representation of the utility model flexible unit;
Fig. 2 is the structural representation that the utility model flexible waist possesses three flexible unit;
Fig. 3 is the structural representation that the utility model flexible waist possesses four flexible unit;
Fig. 4 is the structural representation that the utility model flexible waist possesses six flexible unit;
Fig. 5 is the structural representation that the utility model flexible waist possesses gag lever post.
In figure: 10, flexible unit; 11, flexible body; 12, grooving; 20, active plate; 30, follower plate; 40, installing hole; 50, screw; 60, gag lever post; 70, spacing hole.
Detailed description of the invention
Below, by reference to the accompanying drawings and detailed description of the invention, the utility model is described further:
A kind of flexible unit for industrial robot Fine Boring as shown in Figure 1, comprises the flexible body 11 of strip, and the sidepiece of this flexible body 11 has multiple grooving 12, and each grooving 12 is spaced apart along the length direction of flexible body 11.
This flexible body 11 can adopt metal material to make, the quantity of grooving 12 and the bearing of trend of grooving 12, can need to come corresponding setting according to the design of Flexible Ability.For making flexible unit 10 each to possessing uniform Flexible Ability, this example can be set as follows:
Grooving 12 is interspersed in the relative both sides of flexible body 11.The spacing of adjacent cutback 12 is equal, and the groove width of each grooving 12 is equal, and the groove depth of each grooving 12 is equal.
Certainly, according to the design needs of Flexible Ability and reset capability, also following setting can be made:
As shown in Figure 1, the groove width of each grooving 12 is increased by the two ends of flexible body 11 gradually to the center of flexible body 11 or reduces gradually.Especially, groove depth can be set as follows: grooving 12 groove depth of flexible body 11 side is greater than flexible body 11 opposite side grooving 12 groove body.
Manufacture processing for convenience, controlled working cost, provide each to uniform Flexible Ability simultaneously, the flexible body 11 of this example is prismatic cylinder, and as shown in Figure 4, the cross section of this flexible body 11 is circular or regular polygon.In other embodiments, the cross section of flexible body 11 also can be symmetrical arbitrary polygon.
As shown in Figure 2-5, adopt a kind of flexible waist for industrial robot Fine Boring of described flexible unit 10, comprise active plate 20, follower plate 30 and at least two described flexible unit 10, active plate 20 and follower plate 30 are parallel to each other and spaced, two ends difference affixed active plate 20 and the follower plate 30 removably of flexible unit 10, each flexible unit 10 distributes about the central axis axial symmetry of active plate 20.
Active plate 20, for being fixed on the mechanical arm of industrial robot, provides active drive ability.Before carrying out Fine Boring, follower plate 30, for being fixed on the end effector of industrial robot, moving under the drive by active plate 20, flexible unit 10 or rotates.When carrying out Fine Boring, owing to can contact between parts to be assembled, causing the motion of rod member to be assembled, driving the motion of end effector, and then drive motion linkage flexible unit 10 deformation of follower plate 30.Fixing for convenience of active plate 20 and follower plate 30, active plate 20 and follower plate 30 can adopt ring flange respectively.
When flexible unit 10 is more than three, the site error on 6 free degree directions can be compensated.When use two flexible unit 10, then become plane mechanism, can site error only on compensated part free degree direction.Certain flexible unit 10 can need to configure more quantity according to the design of Flexible Ability.Especially, as shown in Figure 4, the setting of flexible unit 10, can adopt the alternate configuration of flexible unit 10 of columniform flexible unit 10 and rectangle.Especially, also the cross section of flexible unit 10 can be set to other arbitrary polygonal shape, and in conjunction with the flexible unit 10 alternate setting of columniform flexible unit 10 with rectangle
Exemplarily, each flexible unit 10 and place, the active plate 20 affixed one end diameter of a circle of this example are greater than and place, follower plate 30 affixed one end diameter of a circle, namely each flexible unit 10 is obliquely installed, make flexible central be positioned at assembling contact point place between part to be assembled, make the rigging error on each direction can not introduce new rigging error on other direction in the process eliminated.The inclination angle of this flexible unit 10 as design variable, for expanding the design domain of this flexible waist further, will control flexible waist Flexible Ability and recovery capability.
Exemplarily, the installation of flexible unit 10 and active plate 20 and follower plate 30 for convenience, be beneficial to change and safeguard, as shown in Figure 2 and Figure 3, active plate 20 and follower plate 30 have the installing hole 40 of multiple circumferentially array distribution, are provided with mounting platform in installing hole 40, and the two ends of flexible unit 10 to be plugged in respectively in installing hole 40 and to lock onto mounting platform respectively by screw 50, accordingly, screwed hole can be arranged at flexible unit 10 two ends to lock for screw 50.
Alternatively, as shown in Figure 5, the described flexible waist of this example also comprises gag lever post 60, active plate 20 and follower plate 30 have the spacing hole 70 of multiple circumferentially array distribution, one end of gag lever post 60 and the spacing hole 70 of active plate 20 affixed, the other end of gag lever post 60 is less than the spacing hole 70 of follower plate 30, to make to form interval between gag lever post 60 other end and spacing hole 70.When there is relative displacement in active plate 20 and follower plate 30; the other end of gag lever post 60 can move in the scope at described interval; compensate to provide rigging error; and when the relative position of active plate 20 and follower plate 30 departs from excessive; for preventing overload; the other end of gag lever post 60 then limits in limited hole 70, thus this flexible waist of available protecting, avoid flexible unit 10 stretching transition and cannot reset.Also back-off head can be set at the other end of gag lever post 60, prevent follower plate 30 to be excessively stretched with in the vertical direction and transship.
Alternatively, owing to having higher requirements to time assembly period in high-speed automated assembling application, so the movement rate of industrial robot is all very fast, accordingly, the mechanical arm reaction rate of industrial robot, rate travel is generally very fast, therefore, when mechanical arm starts to accelerate to start, due to inertia, active plate 20 has started to depart from follower plate 30, but follower plate 30 still keeps static, now flexible unit 10 is easily caused to stretch excessive, and cause follow-up the rocking of follower plate 30, after causing rocking, just must wait for that flexible waist device carries out assembly manipulation after static again when assembling, assembly period can be increased like this, for solving this problem, the flexible waist of this example makes following setting: the described flexible waist of this example also comprises retaining mechanism (not shown), this retaining mechanism has fixed part and is stretched out by fixed part and make the tight lock part of expanding-contracting action, wherein: fixed part is fixed on active plate 20, tight lock part switches between the position that retraction departs from follower plate 30 and stretches out locking follower plate 30, or, fixed part is fixed on follower plate 30, tight lock part switches between the position that retraction departs from active plate 20 and stretches out locking active plate 20.
Retaining mechanism can adopt pneumatic actuation, when mechanical arm starts, tight lock part is made to stretch out locking active plate 20 or follower plate 30, make active plate 20 and follower plate 30 by fixed part, tight lock part be connected to form rigid unitary so that mechanical arm starts fast and movement fast, avoid rocking, and when needs assemble, regracting tight lock part, removes being rigidly connected of active plate 20 and follower plate 30, makes flexible unit 10 drop into rigging error compensation work.
Be assembled to Kong Zhongwei example with rod member, adopt the operation principle of this flexible waist as follows:
Because rod member to be assembled has rigging error, so rod member accurately cannot fall into hole, rod member will drop in the chamfering on hole.Along with robot proceeds assembling, at this moment flexible waist will utilize the flexible unit 10 of self even Discrete Symmetry distribution to produce elastic deformation, is slipped on hole by rod member to be assembled passively, thus compensate for the rigging error in rod member to be assembled and hole.After rod member inserts in the hole, if any the rigging error on angle direction, the flexible unit 10 in flexible waist device can adjust the angle of rod member to be assembled again by elastic deformation, thus the error on offset angle direction, complete assembling.When assembling completes after without External Force Acting, the flexible unit 10 of flexible waist can set back rapidly.
The design of the flexible central of flexible waist is joined generating plane at rod member end also immediate shipment, then the rigging error of linear displacement can not cause new rigging error when elimination, and angle rigging error also can not cause other new rigging errors when elimination.Especially, when the active plate 20 of flexible waist, follower plate 30 are and are horizontally disposed with, the rigging error of linear displacement refers to the rigging error of horizontal direction.
To one skilled in the art, according to technical scheme described above and design, other various corresponding change and deformation can be made, and all these change and deformation all should belong within the protection domain of the utility model claim.