WO2013029069A1

WO2013029069A1 - Manipulator

Info

Publication number: WO2013029069A1
Application number: PCT/AT2012/000209
Authority: WO
Inventors: Franz Ehrenleitner
Original assignee: Eb-Invent Gmbh
Priority date: 2011-08-30
Filing date: 2012-08-06
Publication date: 2013-03-07
Also published as: DE102012002402A1

Abstract

The invention relates to a device by means of which a tool, a medical appliance, or another object can be pivoted about a virtual pivot point (4) fixed in space and about a virtual axis (4') fixed in space. The pivoting movement is achieved in that the device comprises at least two flat movement grids (1), each of which comprises two parallelogram linkages (8:CKGF; 9; HIED) and optionally a four-bar linkage (10; ABHG). The planes of the movement grids can be arranged parallel to one another or intersect one another in a straight line that includes the pivot point. If three movement grids are provided, said grids intersect preferably in a common straight line. The invention also relates to a novel kind of the flat movement grids used.

Description

manipulator

The invention relates to a device by means of which a tool, a medical instrument, a sample, a workpiece or other object can be pivoted about a fixed in space fulcrum or fixed in space axis of rotation, according to the preamble of claim 1 and DE 94 16 957 U.

In a variety of devices, especially in processing machines, but also in medicine, for example in micro-operations, in various diagnostic procedures and the like, it is necessary that a tool or a camera or a sensor, a milling head, a nozzle, a laser beam, a mirror , a polishing device, a welding device, a toy, a sample, etc., is not only moved along a predetermined path, or is always directed to a fixed point, but also that the processing device, observation device, etc. in is a predetermined angle to the respective processing point. Since, depending on the various parameters, which also have to do with the work to be performed, there are changes in the desired angular position at predetermined locations or partly predetermined, partly spontaneously resulting times, there is a need to provide devices which are able to transmit the necessary angle changes to the tool, which is understood to mean anything possible in the sequence, without changing the working point. An axis of rotation about which such movement occurs is referred to in the specification and claims as "virtual" because it is not materially realized on the device.

There are a number of requirements placed on such devices:

On the one hand, these devices should be lightweight and built with little mass to make rapid changes in the situation without large motor forces and thus without much energy.

Despite the required ease, the devices should be so stiff that significant reaction forces and inertial forces can be taken over and dissipated without causing harmful deformations that could affect the work result. It should be free around the working points, the virtual fulcrum, enough space to allow access to the workpiece, its insertion, application and possibly movement while working easily and easily.

It should be able to control and regulate the movement of the device quickly and accurately, in particular recursive calculations should be avoided, the calculation in the form of closed solutions should be possible.

A planar device according to the preamble of claim 1, which is able to perform in the plane movement about a virtual pivot point, is known from the aforementioned DE 94 16 957 U. This device consists of two Gelenksparallelogrammen, wherein the one Gelenkgleichallelogramm is fixedly mounted with one side and the other joint parallelogram either quasi on the first parallelogram is seated and with him the solid side opposite side has in common, as well as the whole second joint parallelogram , is extended, wherein the other sides of the Gelenkgleichallelogramms parallel to the other sides of the first joint parallelogram or consist of their extension. From EP 595 291 a similar device consisting of a juxtaposition of joint parallelograms is known, as well from DE 100 15 510, corresponding to US 2003/0109825, now US 5,882,294. These publications refer to medical devices and are used in particular for performing complex surgical procedures, which are possibly no longer done by hand, but by means of actuators by remote control or automatically according to a predetermined program by a computer.

These are based on the combination of two parallelograms, which are linearly provided with two common, non-buckling passing sides, are simple in construction, but, if a large tilt angle is to be provided, require such proportions that their mechanical stability suffers. Another device, which allows a planar pivoting movement about a virtual pivot point and is mechanically significantly more stable than the previously discussed, according to the invention, the following, for which there is no model in the prior art:

It has this plane kinematics, hereinafter referred to together with the previously discussed kinematics mostly "motion grid", two Gelenkparallelogramme that have one of their vertices in common and their not going through this common corner points, the base and the free end face, with the intersection Their extensions define the virtual fulcrum and their other sides, which do not go through the common fulcrum, are rigidly extended to their point of intersection, thus creating a four - bar linkage coincident with each of the parallelograms on one side Corner points when holding the base so deformable that the free end face is always directed to the virtual fulcrum.Finally, this motion grid consists of the two joint parallels and a four-bar linkage, whereby the rigidity and articulation are increased ldung, in which the four-bar linkage mutated to a (third) articulated parallelogram, a special case, which leads to the aforementioned motion gratings, if then dispensed with one of the internal connections.

In order to make a spatial (spherical) movement out of the planar pivoting movement of all these motion gratings about the virtual pivot point, it is known in the prior art to make the stationary side of the first parallelogram pivotable about its longitudinal axis, thereby simply the entire working surface of the parallelogram around this line, which indeed contains the virtual fulcrum, is twisted.

Such a configuration is also possible with the new motion grille, but all such constructions have the disadvantage of being extremely soft against forces which are not within the plane of the motion grating, so that there are rapidly noticeable deviations from the straight state of the individual bars of the motion grating comes, which also causes a further deflection in the episode the forces lying substantially within the plane of the movement grid come about, since the loaded bars are already subjected to bending and already tend to buckle. That this is disadvantageous for the joints in the fulcrums, needs to be mentioned only in passing.

There is thus a need to specify a construction mentioned above, also suitable for the spatial area, which does not have the disadvantages mentioned; The solution according to the invention can also be used advantageously for the further level application, since all externally acting forces which are not within the plane of the movement grating, as well as all moments whose axes are not normal to this plane, are best suited to the construction according to the invention be recorded.

An embodiment of the invention now consists in the combination of at least two such motion grids, they are according to the invention or not, which are arranged according to a first variant in space so that the intersection line of their planes is parallel to the free end faces of the two motion grid and the two free End sides are connected by a rigid platform, this allows a spherical movement of the platform about a virtual pivot point and each platform-fixed axis parallel to the two end faces describes around the virtual fulcrum a spherical movement. In the course of this movement, the two motion grids perform not only their movements within their respective plane, but also a rotation about their respective base or about the axis defined by the base. In one embodiment, the two end faces of the two motion gratings are formed coincidentally, whereby the movable platform degenerates to an axis, which can be represented by a sleeve on which the two motion gratings attack. This case occurs when, geometrically speaking, the extensions of the two bases and the extensions of the (coinciding) free sides have a common point of intersection.

The invention will be explained in more detail below with reference to the drawing. It shows or show 1 is a schematic representation of a new planar movement grid, as it can be used for the device according to the invention,

2 is a purely schematic representation of the mobility of a planar movement grid according to FIG. 1,

3 shows a device according to the invention with two aligned motion grids, FIG. 4 shows a device according to the invention with two mutually intersecting planar motion gratings,

5 shows a variant with two intersecting plane motion gratings, FIG. 6 shows a further variant with two intersecting planar motion gratings,

7 shows a variant with two intersecting, mechanically reinforced motion gratings,

9 shows a variant with three intersecting plane motion grids and FIG. 10 shows a planar motion grating according to the prior art, as it can be used for the device according to the invention.

Fig. 1 shows an example of a movement grid 1, as it can be used for a device according to the invention. This motion grid has a first parallelogram, a base parallelogram 8, with the sides C, K, G, F and a second parallelogram, an end parallelogram 9, with the sides D, H, I, E on; with a common fulcrum 2 at the intersection of sides F and D. The "outer" sides K and I are rigidly extended beyond their hinged connection points with sides G and H, indicated by the hatched triangles, to their intersection point 3, in For full length these sides are designated A and B. The extensions of the sides K and I in their form A and B together with the sides G and H of the two articulated parallelograms form a four-bar linkage 10.

Considering side C as stationary, thus as a basis, the motion grid in the plane (drawing plane) is deformable in the manner described by the hinged connection through the individual points of intersection, but always such that irrespective of the instantaneous configuration of the movement grid, the extension of the base C, the extension of the free end face E always the same Point, the virtual pivot point 4, cuts. The lengths J and L are always maintained, as an interchange of ideas of the parallelograms and the mobilities shows immediately, the free end E performs around the point of intersection 4 "of the extension of the base C with the extension of the free end face E a real spherical motion Intersection point 4 "and axis 4 always coincide, as well as possibly the trace of a virtual axis 4 '.

This condition is always met if the following geometric conditions are met, where the letters standing for the individual bars mean their length:

I = (B * L) / (L + E) K = (J * A) / (J + C)

D = (B * L) / (L + E) F = (J * A) / (J + C)

E = H G = C

The dimensions X and Y shown in FIG. 1 and also dimensioned serve only to symbolize the rigid design of the edges or bars A and B, in order to indicate that these bars are also subjected to bending as a result of the points of application of the bars G and H, respectively Therefore, to be dimensioned accordingly. It should also be noted that in these relations the points 4 ", 2 and 3 always lie on an (imaginary) line 11.

Fig. 2 shows, omitting almost all reference numerals, different positions of a movement grating 1 of FIG. 1 and thus the large angular range, such a motion grid in the leadership of a tool in the axis of the free end E with respect to a far out of the device virtual fulcrum 4 is able to deliver. This motion grid is also individually usable, not only obvious as a planar kinematics, but also three-dimensional, for example, when it is rotatable about the axis of its base C.

FIG. 10 shows a plane movement grating according to the prior art, as is known in particular from the abovementioned DE-U. The two Gelenkparallelogramme and their connection are clearly visible, as well as the rotation around the Base axis, by means of which the spherical movement of the tool 14 is achieved around the pivot point "D".

According to the already mentioned advantageous embodiment of the invention, at least two such planar motion gratings, no matter which construction, combined with each other to come to the desired mobility about an axis or about a pivot point. In a first variant according to FIG. 3, two such motion gratings are provided in alignment with one another and braced in accordance with one another, thus forming a truss body which allows rotation about an axis. In FIGS. 1 and 2, the course of this axis corresponds to the virtual pivot 4, the axis is normal to the plane of representation.

In Fig. 3, such a framework is shown in three different positions, respectively in side view and in perspective view, the diagonal stiffeners 5 for receiving forces or force components in the direction normal to the plane of the movement grid 1 and to secure the aligned position of the movement grid are clear to see. The virtual axis 4 'is shown only in the side views, their coincidence with the intersection 4 "is evident.

In a second embodiment shown in Fig. 4, the two movement grids 1 are arranged so that the extensions of the two bases C and the two free end faces E intersect each other in the virtual pivot point 4, the actual tool spindle can then on a platform 6, the the two free end faces E formed or fixedly connected to these are fitted and remains in the sequence with each movement of the device directed to the virtual pivot 4; she performs a spherical movement around the virtual fulcrum 4.

In a further, shown in Fig. 5 embodiment, it is possible, as already briefly mentioned above, between the two free end faces E, even if the intersections 4 "of their extension and the extension of the bases C coincide only for a respective motion grid 1 to attach a fixed platform 6 to the free end faces E and in turn to position the tool axis so that they always point to the virtual pivot point 4, which then between said intersections lies, is directed. In Fig. 5, the base C of the "rear" motion grid is hidden in the perspective view, its axis of rotation is visible in the region of the intersection 4 "and there denoted by" C ".

FIG. 6 shows another variant in which the two bases C of the two motion gratings 1 coincide. Shown is a corresponding half-timbered body in three different positions each in a simplified side view and perspective view The movement of the two motion grating 1 about the base C associated rotation axis is externally, for example, to cause an actuator (not shown), optionally, the base C also the end of a robotic arm or similar. Again, diagonal stiffeners 5 are provided to absorb shear forces. A fixed platform 6 is formed between the free end faces E, the axis directed to the virtual pivot point 4 is entered purely schematically. The "side views" show one of the two motion grids 1 without regard to the second or the stiffeners, therefore the goose feet.

In order to be able to absorb forces or force components which normally act on the plane of one of the movement grids, it is possible, on the one hand, to make this movement grille correspondingly solid, but it is advantageous to provide it with lateral struts, wherein the strut supports the movements of the movement Grid with power, but it derives the lateral forces.

An example of such a bracing is shown in an interesting embodiment of a device similar to that of Fig. 5 in Figs. 7 and 8: The planes of the two movement grids 1 coincide in a position shown in Fig. 7 together. The axes of the two bases C intersect each other at a point through which the tool axis 10 passes. It is possible to move the tool axis along the connecting line of the two fulcrums while still maintaining motion around a virtual fulcrum (which is then eccentric). This allows the device to be swiveled through the plane state, since both plane movement grids 1 are provided with lateral struts 7 without the formation of a singularity. Fig. 8 shows six different positions of this device in a perspective view, resulting in the large swivel range in in all directions. In these positions an over-determination occurs due to the double formation of the lateral bracing, but this does not play a disadvantageous role.

In FIG. 7, both movement grids are each provided with a lateral strut 7, which receives and derives force components acting normal to the grating plane. This bracing makes of course the deformation of the four-bar linkages and is designed accordingly. It is true that the strut consists of a framework over at least one of the sides A, B, F + H, D + G, with the proviso that stiffeners over F + H, and D + G are articulated in the hinge points, as the figure indicates. As a lateral bracing 7 while the entirety of the framework is understood.

A different embodiment shown in FIG. 9 with the derivation of transverse forces consists of three motion grids 1 whose planes are preferably arranged rotated by 180 ° about a central axis (this in a "normal position", since during operation the angular positions of the planes in order to be able to derive each of the occurring force components within one of the grids even in very extreme positions, in which case it is preferred that the axes of the three bases C do not run in a normal plane to the imaginary central axis of symmetry, but instead a point "below" this normal plane, since thereby an increase of the cone angle, in which the tool axis 10 is to be set is achieved.

In the illustrated and described embodiments, the motion grids used in a device are always equal to each other (congruent), but this is not necessary as long as only the above-mentioned geometric conditions for each individual motion grid are met. For reasons of manufacturing costs and storage, the use of such mutually identical motion grid is generally preferred, only in devices for special designed surfaces, it is conceivable that the use of uneven motion grid brings benefits. The points of application or connection points between the motion gratings and the platform carrying the tool, if it is not a platform firmly connected to the free end faces, thus in the variants according to FIGS. 7-9 have suitable mobility, as shown specifically in FIG. 7 indicated. In the variant according to FIG. 9, each connection 11 must be rotatable about the tool axis 10 independently of the others, each connection 11 should be mounted in alignment with the associated connection 11 '(for example as in FIG. 7 by the rod-like manner spaced from the tool carrier Connection indicated).

FIG. 10, which shows an example of a planar motion grating according to the prior art, has already been explained in more detail above. It is well recognizable that the achievable swing angle is significantly smaller than with the new motion grids.

For those skilled in the art, the corresponding configuration of the compounds and the motion grid, each of which can be applied independently and combined with each other in a variety of ways or individually applied, with knowledge of the invention easily possible. Depending on the field of application, all materials customary there are suitable materials.

When using the new motion grids, it is necessary for the two articulated parallelograms (8, 9) to have a common pivot point (2) at their corners (F, G; D, H) such that the two adjacent parallelogram sides (G, H) coincide with the always straight extended sides (AB) form the four-bar linkage (10: ABHG), that the side (C) represents the base and that its extension with the extension of the free end face (E) always the fixed virtual pivot point (4) and the fixed , virtual axis (4 ') intersects.

Preferably, the lengths of the pages meet the following requirements:

I = (B * L) / (L + E) K = (J * A) / (J + C)

D = (B * L) / (L + E) F = (J * A) / (J + C)

E = HG = C where A to I and K are the lengths of the sides designated in claim 1 with the same letter and L and J are the distances from the fixed virtual pivot point (4) and from the fixed, virtual axis (4 ') to the intersection point (FC) or the intersection point (ED).

Further fields of application of the invention relate, for example:

• Examination chairs (with special virtual fulcrum around the area to be treated) e.g. Dentist's chair with virtual pivot around mouth or for e.g. for colonoscopy etc.

• Hospital beds with this kinematics for relocating recumbent patients, so the nursing staff has less effort

• Kinematics as a table for the examination of samples of all kinds. In the optical inspection, stereomicroscopy you want to rotate the samples under the microscope around the focused (virtual) point. It is also possible to record 3D images through controlled axes of the table

• Processing and soldering of circuit boards under the microscope (miniaturized components)

• Diffraction technique, in which X-rays are shot at a sample to carry out the chemical analysis / composition of the sample. It is conceivable either to virtually rotate the table with the sample or to rotate the detectors and the beam source itself around the sample point with the kinematics.

List of reference numbers:

1 plane motion grid 8 basic parallelogram

2 common pivot 9 frontal parallelogram

3 Intersection AB 10 four-bar linkage

4 Virtual pivot 11 Tool axis

4 'virtual axis 12 Empty

4 "intersection CE 13 empty

5 diagonal bracing 14 tool

6 Platform D pivot point

7 lateral bracing

Claims

claims:

1. Device by means of which a tool, a workpiece, a medical device, or another object about a solid in space virtual pivot point (4) or about a solid in space, virtual axis (4 ') can be pivoted, characterized characterized in that it comprises at least two planar motion gratings (1) each having two joint parallelograms (8: CKGF; 9: HIED) and optionally a four-bar linkage (10: ABHG).

2. Apparatus according to claim 1, characterized in that the planes of the two planar movement grid parallel to each other and the two intersections (LJ) define a common solid virtual axis (4 ').

3. A device according to claim 1, characterized in that the planes of the two planar motion grid intersect each other in a straight line parallel to the two bases and the common intersections (LJ) defines a common fixed space virtual pivot point (4).

4. The device according to claim 3, characterized in that the free end faces (E) of the movement grid carry a platform (6) which is pivoted about the fixed space virtual pivot point (4).

5. Device according to one of the preceding claims, characterized in that at least one of its planar movement grid (1) has a strut (7).

6. The device according to claim 6, characterized in that the strut consists of a framework over at least one of the sides (A, B, F + H, D + G), with the proviso that stiffeners on (F + H, D + G) are articulated in the hinge points.

7. The device according to claim 1, characterized in that it comprises three planar movement grid (1) whose planes have a common cutting axis.