WO2025051649A1 - Robot device for endoscopic inspections - Google Patents

Abstract

In order specify a robot device (1, 4) for endoscopic inspections, having a, preferably elongate, base shaft (5) and at least one link element (9, 11), attached so as to be rotatable through an angle, with adjusting means (23, 31, 40) for varying the angle, said robot device being able to be operated in an automated manner with great precision and also making it possible to also use larger instruments, the invention proposes that a joint element (8, 10, 11) is provided, with which the at least one link element (9, 11) is attached such that it is rotatable about exactly one axis of rotation (30), and that the base shaft (5) has at least one cutout (12) in cross section on an outer side.

Description

Robotic device for endoscopic inspections

The present invention relates to a robotic device for endoscopic inspections, comprising an elongated base shaft and at least one link element mounted so as to be rotatable about an angle and having adjusting means for varying the angle.

Robotic devices of the type mentioned above, known as universal robots for endoscopic inspections, have a very broad range of applications. In particular, they can create repeatable and standardized recording conditions for optical inspections and automated data acquisition. Endoscopic and spatially confined inspections are often performed manually. Manually operated endoscopes are used for this purpose. Such robotic devices are particularly used for industrial inspection and repair tasks.

Robotic devices of the type mentioned above are being developed primarily in the field of engine inspection. The known robotic devices are predominantly of the continuum robot type. As described, for example, in EP 4 101 605 A1 in Figure 2 and the associated figure description in paragraphs [0020] to [0021], a continuum robot has guide elements connected via flexible wires. The robot arm thus formed can assume a continuum of angular positions in space by varying the wire length using an actuator.

WO 2019/239046A1 discloses a mobile robot for inspecting a turbomachine. In this robot, several link elements are connected to each other via a ball joint. JP 2022-115133A discloses an inspection device for inspecting the interior of an object to be inspected using an endoscopic camera. In this device, a robot arm consists of link elements connected to one another via flexural and torsion joints.

DE 10 2014 205 036 A1 discloses an endoscopic instrument for connection to a surgical robot. In this instrument, a mounted limb element can be actuated via a cable pull system.

US 5,797,900 A discloses a wrist mechanism for a surgical instrument for performing minimally invasive surgery.

With existing robotic devices for endoscopic inspections, the use of continuously flexed structures makes it extremely difficult to measure the robot's current position using sensors. This may not be a problem in teleoperated systems with human supervision. However, with an automated inspection, significant positional deviations can occur over time. Precision decreases accordingly. Furthermore, system rigidity is reduced, as deviations from the target positions due to external disruptive forces are difficult to detect. A further disadvantage of existing robotic devices of the type mentioned above is that they require complex calibration at the beginning of each precise inspection.

Finally, previously known robotic devices have the disadvantage that the use of end-effector systems is limited, since the adjusting means for varying the angle are arranged in such a way that they prevent the integration of certain components into the endoscope. For example, the standardized connectors of the The fiber optics of a laser system often have such large diameters that they cannot be threaded through the endoscope or can only be threaded with great effort.

Against the background described, the object of the present invention is to provide a robot device of the type mentioned at the outset which can be operated automatically with great precision and which also makes it possible to use larger instruments.

The object underlying the invention is achieved with a generic robot device in which a joint element is provided, with which the at least one link element is attached such that it can be rotated about exactly one axis of rotation. According to the invention, the link element is thus attached with a discrete joint that can only be deflected in one plane. This enables the integration of position sensors into the joint, and control deviations can be compensated for. The advantage is significantly improved precision during operation of the robot device compared to conventional robot devices with continuous joints that can be deflected in a continuum of planes, as is the case with a ball and socket joint, for example.

According to an alternative approach, the object underlying the invention is achieved in a robot device of the type mentioned above in that the base shaft has at least one recess on an outer side in cross-section. This measure makes it possible according to the invention to use end effector systems with the robot device according to the invention that have a larger diameter than the base shaft. This is because the recess allows end effector systems to be connected to the base shaft so that the systems do not have to be threaded through the endoscopic robot.

In an advantageous embodiment of the invention, two or more link elements are provided, each of which is rotatably mounted relative to the base shaft and/or relative to another link element. The robot device according to the invention thus acquires additional rotational degrees of freedom. The inventive use of joint elements, each of which is rotatable only about one axis of rotation, i.e., only in one plane, simultaneously enables precise control, which is suitable for automation.

In a particularly advantageous embodiment of the invention, at least one link element is attached to the base shaft and/or to another link element in such a way that a lever arm is created between the outer contour of the link element. This allows the lever arm of the joint to be increased, thus increasing the achievable torque when varying the angle with the adjusting means. This can be advantageous in certain applications, for example, to release a jam in the space to be inspected.

In a further advantageous embodiment of the robot device according to the invention, at least one link element is mounted opposite the rotational axis of another link element, with the axis angle preferably being 90°. In particular, with the rotational axes rotated by 90° to each other, the robot device according to the invention provides two rotational degrees of freedom, which makes it possible, for example, to combine a pitching movement with a yawing movement.

In a particularly preferred embodiment of the robot device according to the invention, the actuating means comprise a, preferably antagonistic, cable pull. In the case of an antagonistic cable pull, the Shortening of one rope section to correspondingly lengthen the opposite rope section. In practice, this is achieved by guiding the same rope over deflection means, so that when a pull is exerted on one end of the rope, a tensile force also acts on the other end. Precise control of the angle of each link element relative to the base shaft and/or relative to another link element can be achieved particularly well with a cable pull. The design, in particular, as an antagonistic cable pull robot makes it possible to shift torque generation outwards, outside of the confined installation space. The advantage of antagonistic force transmission using the cable pull is that the system can be pretensioned. This means that the respective link element is supported on the base shaft or on another link element by the antagonistic cable pull and a suitable deflection unit. The rigidity of the robot device according to the invention is advantageously increased in this way. At the same time, play is eliminated, which is crucial for automation and precision.

To ensure longevity and to avoid friction effects that are difficult to model, one embodiment of the robot device according to the invention provides for cable guide means for guiding and/or deflecting the cable pull. To guide the cable pull, a link element can be provided with a guide track and/or guide groove formed on an outer contour.

In this context, it has proven advantageous for the rope guide to include at least one pulley. Pulleys can be used to minimize sliding friction during rope guidance. In a further development of the robot device according to the invention, the cable guide means comprise at least a triplet of three deflection pulleys whose axes of rotation are aligned parallel to one another and are arranged in a plane in the shape of an isosceles triangle, wherein the base of the isosceles triangle is arranged at the proximal end of the cable guide.

The arrangement of pulleys allows for a deflection of more than 90° in both directions. The triplet of three pulleys according to the invention makes it possible to guide additional cables through the first joint element of the first link element and redirect them during rotational movements. After the additional cables have passed the first joint via the triplet of three pulleys, the additional cables are redirected so that they are aligned to match the subsequent rotary joints of other link elements of the robot device according to the invention.

To be suitable for automated operation, the robot device according to the invention can be provided with angle sensors to measure the angle of the link element, with angle sensors being assigned to each joint element in particular. By integrating angle sensors, control deviations can be compensated for, thereby advantageously achieving a high level of precision in the control of the robot device according to the invention. These measures allow the compensation of external interference factors and modeling inaccuracies. This, in turn, enables longer autonomous missions of the robot device according to the invention.

In particular, a Hall sensor can be used to detect the angular position of each individual joint element concentrically over its axis of rotation The Hall sensor can detect the angle of rotation via a magnet embedded in the axis of rotation of the joint element.

It is particularly advantageous if the joint element is provided with stop means, preferably on both sides, to limit the angular travel of the angle. Mechanical stops are particularly suitable as stop means. Using the stop means, the angle sensor means can be referenced, for example, to zero them exactly at the stops. This measure increases the autonomy of the robot device according to the invention. This makes it capable of calibration and referencing. Calibration of the robot device according to the invention can thus take place automatically without manual intervention by an operator. The detection of a rotational movement into one of the given stops can, within the scope of the invention, be carried out in particular by an external control unit in which motor currents are measured, analyzed, and limited. Furthermore, within the scope of the invention, the reaching of the stop can be detected via electronic contacts on the stops themselves. Normally open contacts are a possible implementation here.

To achieve a maximum number of degrees of freedom, in one embodiment of the invention, separate adjustment means are assigned to each link element. For example, each link element and the associated joint element can contain a separate antagonistic cable pull, which can be activated via suitable cable guide means, in particular deflection pulleys, independently of the antagonistic cable pulls of other link elements of the robot device according to the invention in order to vary the angle.

If the base shaft in the embodiment of the invention has a substantially circular and/or oval cross-section, It is advantageous to accommodate elements relating to the design of the adjusting means and, if applicable, measuring technology inside the circle, so that the recess in the cross-section on the outside of the base shaft is available for accommodating instruments.

In addition, a circular and/or oval cross-section has been shown to be advantageous for the rigidity of the base shaft, which in turn is beneficial for the precision when performing endoscopic inspections.

In a further advantageous embodiment, the recess in the cross-section of the base shaft has the shape of a circular segment. In particular, the cross-section of the base shaft can have a semicircular outer contour if the recess is a correspondingly semicircular circular segment. In this embodiment, all devices for the adjusting means, in particular guides for antagonistic cable pulls, are accommodated in the semicircular cross-sectional area of the base shaft. This leaves an area with a complementary cross-section available for instrumentation. The invention is not limited to a semicircular cross-section. Rather, within the scope of the invention, any theoretically arbitrary ratio of the circular division can be selected, which is subject to a task-specific design of the overall structure. The division can occur along a secant intersecting a circle. In the case of a half/half division, this secant can also be the diameter.

Preferably, the adjusting means and/or data lines are arranged in a radially inner region of the cross-section of the base shaft. In contrast to prior art designs in which cables are arranged on the outer circumference of the cross-section This measure allows for the use of larger end effector systems, as they do not have to be fitted into the interior of the base shaft, which is surrounded by cables.

In order to be able to use cable pulls, especially antagonistic cable pulls, as adjusting means, it is advantageous if the base shaft has longitudinally extending bores for the passage of the adjusting means. In particular, if there are several link elements each attached via joint elements, bores are provided for each corresponding adjusting means. In the case of antagonistic cable pulls as adjusting means, a pair of bores is provided for each adjusting means, according to the invention.

In an advantageous embodiment of the robot device according to the invention, the base shaft is provided on its distal end face with receiving means for receiving the joint element. The receiving means can, in particular, be bores for receiving locating bolts on the side of the link element. In conjunction with an antagonistic cable pull as an adjusting means, the link element is positively and non-positively attached to the base shaft, optionally via its joint element.

In order to ensure a high rigidity of the robot device as a prerequisite for autonomous operation with simultaneous high precision, it is advantageous within the scope of the invention if the base shaft and optionally further elements, in particular the link elements, are made of a rigid material, preferably titanium.

In an embodiment of the robot device according to the invention, the base shaft is operatively connected at its proximal end to actuating means for driving the actuating means. The actuating means may take the form of a control box. For example, a modular actuating unit for controlling the antagonistic cables may be arranged between the proximal end of the base shaft and a support system to which the base shaft is attached.

The actuation unit can be divided into various parts. The core elements can be a transmission unit and a drive unit. The drive unit can consist of several EC motors arranged symmetrically in a circle, which are responsible for the rotational movement of the cable pull drum of the opposing cable pull. The respective motor control units can be located in the space between them.

The motor control units can be combined on a common circuit board.

In the transmission unit, the rotary motion of the motors can be converted into a translatory pulling motion of the cable pulleys. The cable pulling forces can be measured using a strain gauge attached to the cable pulley.

The cable pulls can be wound on a drum. The plug-in transmission unit can be mounted on the drive unit.

In the rear part of the actuation unit there can be a control computer which can be responsible for controlling the entire robot system according to the invention.

To distribute the signals within the robot device, several data lines can extend along the main axis of the actuation unit. The control computer can also provide communication with an external carrier system to which the proximal end of the base shaft is attached. In this way, relevant data for the execution of complex trajectories can be collected from both an external carrier system and the robotic device described here.

If the actuation unit consists of several circular modules, the modules can be adapted and exchanged as needed. This advantageously allows for different installation dimensions to be realized depending on the application.

The base shaft is preferably mounted concentrically to a circular actuation unit. This simplifies the alignment of the individual components.

Alternatively, within the scope of the invention, it is also conceivable for the base shaft to be mounted at an angle to the actuation unit. This can be advantageous in hard-to-reach working environments.

If the actuation unit is circular and the base shaft is mounted concentrically, the degrees of freedom are expanded by rotation. The rotation can be achieved using an externally connected actuation unit, such as a rotary table.

In a particularly advantageous development of the robot device according to the invention, covering means are provided for covering the recess, wherein the covering means are preferably designed to be plugged onto the base shaft. In the case of a base shaft with circular cross-section, this can be covered by two half-pipes.

To increase the degrees of freedom of the robotic device according to the invention, the base shaft can be connected to a translationally and/or rotationally movable support system, in particular to a collaborative lightweight robot and/or a cobot. In combination with such a support system, the robotic device according to the invention can be moved to various endoscopic maintenance entrances and penetrate cavities there.

If the support system allows translational movement, the base shaft can be extended and retracted, adding another degree of freedom to the robotic device.

If the support system is also rotationally movable, an additional degree of freedom is obtained.

If, according to the invention, the link elements attached to the base shaft are also provided with independent adjusting means, a total of five degrees of freedom is obtained, for example in the case of two link elements.

The invention is described by way of example in a preferred embodiment with reference to a drawing, wherein further advantageous details can be taken from the figures of the drawing.

Functionally identical parts are provided with the same reference symbols.

The figures in the drawing show in detail: Figure 1 : an endoscopic robot with an actuator on a

Support arm in perspective view;

Figure 2: a detailed view of area II in Figure 1 of the endoscopic robot from Figure 1 in a side view

Figure 3: a cross-section along the line III - III in Figure 2 through the base shaft of the endoscopic robot of Figure 2;

Figure 4: a detailed view of the robot device from Figure 2, but in a different position and with the cover tube removed;

Figure 5: a perspective view of the connection between the base shaft and a link element via a joint in a partial section of another embodiment of the invention;

Figure 6: a representation of the object from Figure 4 rotated by 180° around the longitudinal axis, with the cable drive visible in Figure 4 removed;

Figure 7: a representation of the object from Figure 6 in a

Section along the line VII - VII in Figure 6, the angular position of the components relative to each other being different from that in Figure 6;

Figure 8: Representation according to Figure 8 in a different angular state of the components to each other;

Figure 9: Representation of the object from Figure 8, but rotated by 90° and in a different state to Illustration of a degree of freedom for performing yaw movements;

Figure 9a: Representation of a section along the line IXa - IX9a from Fig. 8;

Figure 10: perspective view of the object of Figure 4 on the area V in Figure 4;

Figure 11: a cross-section along the line XI - XI in Figure 2 through the base shaft of the endoscopic robot of Figure 2;

Figure 12: a cross-section along the line XII - XII in Figure 2 through the base shaft of the endoscopic robot of Figure 2;

Figure 13 is a perspective sectional view taken along section line XIII-XIII in Figure 2;

Figure 14 is a perspective view obliquely from the front of the distal end 7 of the base shaft 5 of the device from the previous figures.

Figure 1 shows a perspective view of an endoscopic robot 1. The endoscopic robot 1 consists of a movable support system 2, an actuator box 3 attached thereto, and a robot arm 4. The support system 2 is a cobot that can move the robot arm 4, which is attached to the support system 2 and is controlled via the control box 3, in a translational and rotational manner, which is not shown in detail here.

The control box 3 contains the drive and transmission unit, also not shown in detail here, for controlling the robot arm 4. Figure 2 shows a side view of detail area II in Figure 1 with the unit comprising control box 3 and robot arm 4 of the endoscopic robot 1 from Figure 1. As can be seen in Figure 2, the robot arm 4 has an elongated base shaft 5. The proximal end 6 of the base shaft 5 is connected to the control box 3 in a manner not shown in detail. A proximal link element 9 is attached to the distal end 7 of the base shaft 5 via a proximal joint 8. The proximal link element 9 is mounted via the proximal joint 8 for rotation about exactly one axis of rotation. The axis of rotation runs perpendicular to the plane of the drawing in Figure 2. Accordingly, the proximal link element 9 is mounted via the proximal joint 8 for rotation relative to the base shaft 9 in the plane of the drawing in Figure 2.

A distal link element 11 is attached to the distal end of the proximal link element 9 via a distal pitch joint 10. By means of the distal pitch joint 10, the distal link element 11 is rotatable about exactly one axis of rotation, which lies in the plane of the drawing according to Figure 2 and is thus offset by an axial angle of 90° relative to the axis of rotation of the proximal joint 8. In this way, the distal link element 11 is capable of performing rotations relative to the proximal link element 9 via the distal pitch joint 10 in a plane perpendicular to the plane of the drawing of Figure 2.

Figure 3 shows a section through the base shaft 5 of the robot arm 4 of the endoscopic robot 1 near the distal end 7 of the base shaft 5 along the line III - III in Figure 2. Figure 3 illustrates that the base shaft 5 has a substantially circular shape in cross section, but has a recess 12 in cross section. In the embodiment shown in Figure 3, the recess 12 has the shape of a circular segment in cross section. In the base shaft 5, on a first secant on This centers a pair of through-hole cable guide bores 15, 16. A proximal antagonistic cable pull for actuating the proximal link element 9 is passed through the cable guide bores 15, 16, which are arranged centrally between the receiving recesses 13, 14 on the same secant as the receiving recesses 13, 14, via the proximal joint 8 to the drive unit (not shown in detail) in the control box 3. The cable pull is not shown in Figure 3. Above the pair of cable guide holes 15, 16 for the proximal link element 9, two further pairs of cable guide holes 17, 20 and 18, 19 are arranged, offset parallel to each other, on a center line of the cross-section of the base shaft 9, which intersects the secant on which the cable guide holes 15, 16 for the proximal link element 9 are arranged at a right angle. The antagonistic cables for triggering a yaw movement of the distal link element 11 are provided through the cable guide holes 17, 20. On the other side, the cable guide holes 18, 19 are provided for guiding the antagonistic cables for actuating the distal link element 11 in a pitching movement direction perpendicular to the yaw movement.

Endoscopic instruments can be accommodated in the area of the recess 12 of the base shaft 5. These can advantageously be larger than the cross-section of the base shaft 5. The reason for this is that the actuation in the lower area of the base shaft 5 is arranged away from the outer circumference of the cross-section. Along the center line, on which the cable guide holes 15, 16, 17, 18, 19, 20 are arranged, there is a sensor circuit board 21. The sensor circuit board 21 serves to transmit signals from Hall sensors as angle sensors of all joints, i.e. the proximal joint 8 as well as the distal pitch joint 10 and the distal yaw joint 41. Furthermore, Figure 3 schematically shows that the The area of the recess 12 of the base shaft 5, in which measuring instruments can be accommodated, is covered with a semi-tubular cap 22. The cap 22 is attached to the base shaft 5 in a manner not shown in detail in the figure.

Figure 11 shows a section through the base shaft 5 of the robot arm 4 of the endoscopic robot 1 near the proximal end 6 of the base shaft 5 along the line XI-XI in Figure 2. The cable guide bores 15, 16 and 17, 20, respectively, and 18, 19 can be seen. Due to the opposite viewing direction of Figures 3 and 11, these are mirror-inverted to each other. A pair of receiving recesses 13, 14 are formed in the base shaft 5 on a first secant and centered thereon. The receiving recesses 13, 14 serve to receive complementarily shaped receiving bolts in the control box 3, whereby the receiving bolts are not visible in the figures. The cables are also not shown in Figure 11.

Figure 12 shows a section through the base shaft 5 of the robot arm 4 of the endoscopic robot 1 in a central section 7a of the base shaft 5 along the line XII-XII in Figure 2. The viewing direction corresponds to that shown in Figure 3. In the central section 7a, the cable guide holes for the cables are not designed as individual holes, unlike the situation at the proximal end 6 and the distal end 7 of the base shaft 5. Instead, recesses 49 are recessed from above and below 50 into the base shaft 5. This is considerably easier to manufacture. In Figure 12, the cable guide holes 15, 16 or 17, 20 or 18, 19, which are formed at the distal end 7 of the base shaft 5, can still be seen due to the viewing direction towards the distal end 7. For further illustration, Figure 13 shows a perspective sectional view along section line XIII-XIII in Figure 2, in the opposite viewing direction to that shown in Figure 3. For clarity, the sensor circuit board 21 is not shown in Figure 13. Figure 13 illustrates that the cable guide bores 15, 16, 17, 18, 19, 20 are formed as elongated holes, which open into the troughs 49, 50 formed from above and below in the central section 7a of the base shaft 5 shown in Figure 12. The actuation cables run freely in the area of the troughs 49, 50.

Figure 14 shows a perspective view obliquely from the front of the distal end 7 of the base shaft 5 of the device from the previous figures. For clarity, the proximal link element 9 and all other components adjoining it in the proximal direction have been removed. The illustration according to Figure 14 shows the actuation cable 31 for the distal pitch joint 10, which is guided through the cable guide holes 18, 19. Furthermore, Figure 14 shows the actuation cable 40 for the distal yaw joint 41, which is guided through the cable guide holes 17, 20. Finally, Figure 14 shows the actuation cable 23 for the proximal joint 8, which is guided through the cable guide holes 15, 16. Furthermore, Figure 14 illustrates the distal receptacle for two complementarily shaped fork parts 51, 52 of the proximal joint 8.

Figure 4 shows a section near the distal end 7 of the base shaft 5 in a top view in the direction of arrow IV in Figure 2. It can be seen first of all that the proximal joint 8 is fastened via the fork part 51, which is positively inserted into the corresponding receptacle on the distal end face of the base shaft 5. The fastening is ensured by the antagonistically guided actuation cable 23. The actuation cable 23 serves to actuate the proximal link element 9 via the proximal joint 8. The actuation cable 23 is guided from the cable guide bore 15 for the proximal link element 9 of the base shaft 5 via a guide groove 24 formed in the outer contour of the proximal link element 9 to a guide channel 53 in the link element 9. The guide channel 53 runs at a right angle to the guide groove 24. Within the guide channel 53, the actuation cable 23 is clamped to a fixation point 54 by means of a grub screw. This can only be seen schematically in Figure 4. This results in an antagonistic actuation. Accordingly, a tensile force exerted by a drive unit in the control box 3, for example on the end of the actuating cable 23 guided through the cable guide bore 15, also leads to a corresponding tension in the opposite end of the actuating cable 23 running through the cable guide bore 16. The arrangement of the deflection pulleys 45 serves to deflect the actuating cable 40 for the distal yaw joint 41.

When the end of the actuating cable 23, which extends through the cable guide hole 16, is pulled into the cable guide hole 16, the actuating cable 23 extends out of the hole 15 through the complementary cable guide hole 15. The cable section protruding from the hole 15 at this end is thus extended.

The rotation axis 26 of the proximal link element 9 relative to the base shaft 5 is attached to the proximal link element 9 in such a way that a lever arm 28 is created between the rotation axis 26 and the outer contour of the proximal link element 9. Depending on the selection of the lever arm 28, the torque exerted by the actuation cable 23 on the proximal link element 9 changes. Figure 10 shows a perspective view obliquely from above of the object in Figure 4, of area X in Figure 4. The illustration according to Figure 10 illustrates in particular the arrangement of the rollers 45, 55 for guiding the actuation cable 40 for the distal yaw joint 41, as well as the rollers 46, 56 for guiding the actuation cable 40 for the distal yaw joint 41. The actuation cable 31 is only guided by the rollers 36 and 37 and then again by the rollers 57, 58. This can also be clearly seen in Figures 7 and 8. The guide rollers 45, 46 lie in a plane which is inclined relative to the plane in which the guide rollers 55, 56 lie. Accordingly, a V-shaped cable deflection is provided. This serves to divide the very tightly bundled cable strands again. This is necessary for the activation of the distal yaw joint 41. The angle of the V-shape allows the spread to be directly influenced. The installation of additional deflection pulleys can therefore be advantageously eliminated.

Figure 5 shows a sectional view through the object according to Figure 4 along the line V-V in Figure 4. However, the angle of rotation of the proximal link element 9 relative to the proximal joint 8 is different from that in Figure 4. Figure 5 illustrates the guide groove 24 formed on the outer contour of the proximal link element 9.

The illustration in Figure 5 also shows the actuation cable 23. Furthermore, Figure 5 clearly shows the roller bearing 29 of the proximal joint 8 and the rotation axis 30. The deflection pulleys 29, 33, 35, 42, 43 and two further deflection pulleys not visible in the figure serve to deflect the cables looped through the cable guide holes 17, 18, 19, 20. Both rolling bearings for the rotation axis 30 are embedded directly below and above link element 9.

The rotation axis 30 is oriented such that the proximal link element 9 is movable relative to the base shaft 5 in the plane of the drawing according to Figure 2. Slipping of the actuating cable 23 relative to the guide groove 24 in the outer contour 27 of the proximal link element 9 is achieved by squeezing it using a grub screw in the proximal link element 9 at the fixation point 54. This is not visible in Figure 5.

A special feature of the endoscopic robot 1 disclosed here is the number of degrees of freedom that can be activated by means of antagonistic cables. Since further degrees of freedom are connected to the proximal link element 9 due to the rotatability of the distal link element 11, additional cables must be guided through the proximal joint 8. Furthermore, the additional cables must be redirected during rotational movements of the proximal joint 8.

The corresponding relationships can be seen particularly well with reference to Figure 6. Figure 6 shows the object from Figure 4 rotated by 180° about the longitudinal axis of the base shaft 5, wherein the position of the proximal link element 9 relative to the base shaft 9 is again different from that in Figure 4.

In Figure 6, the actuation cable 23 for the proximal joint 8 runs below the plane of the drawing according to Figure 6. Figure 6 also shows an actuation cable 31 for the distal pitch joint 10. This is guided through the cable guide hole 17 for the distal link element 11 to trigger a pitching movement and back to the cable guide hole 20 for the distal link element 11 for the yaw movement in the base shaft 5. The cables run in pairs through the cable guide holes 15, 16 for the proximal link element 9, the cable guide holes 20, 17 and 19, 18 respectively. By means of this arrangement, in principle, further antagonistic cables can also be pulled through the proximal joint 8 within the scope of the invention.

The actuation cable runs over a triplet 32 arranged at the proximal joint 8. The triplet 32 consists of a main deflection pulley 33 and two guide pulleys 35, 62. The locations of the axes of rotation of the two guide pulleys 62, 35 together with the main deflection pulley 33 form an isosceles triangle. The base of the isosceles triangle is a connecting line between the axes of rotation of the two guide pulleys 62, 35. Said base is arranged at the proximal end of the cable guide. The main deflection pulley 33 has the same diameter as the two guide pulleys 62, 35, which also both have the same diameter. In an alternative possible implementation (not shown), the two guide pulleys 34, 35 have a different diameter than the main deflection pulley 33.

The actuation cable 31 for the distal joint 10 is guided along the respective facing sides of the guide pulleys 62, 35 and from there to the main deflection pulley 33. The triplet 32 ensures secure guidance of both ends of the actuation cable 31 for the distal joint 10 in all angular positions assumed by the proximal link element 9 due to updates by the actuation cable 23.

The triplet 32 of deflection pulleys, in cooperation with the three pulleys, enables a deflection of more than 90° on both sides. After the actuation cable 31 for the distal joint 10 has been passed over the proximal Once joint 8 has passed over triplet 32, it is redirected so that it is aligned with the subsequent pivot joints. This is achieved by suitably arranged guide rollers 36, 37, which are mounted on the proximal link element 9.

In the proximal direction of the guide of the actuation cable 31 for the distal joint 10, a further pair of guide rollers 36, 37 is connected on the side of the proximal link element 9. The actuation cable 31 is in turn guided over the mutually facing sides of the guide rollers 36, 37. In this way, the actuation cable 31 for the distal joint 11 is able to maintain tension and therefore remain guided at all angular positions that the proximal link element 9 can assume due to actuation by the actuation cable 23 relative to the position above the base shaft 5.

Figure 7 shows the object from Figure 6 rotated 90° into the plane of the drawing, whereby, in contrast to the state shown in Figure 6, the base shaft 5, the proximal link element 9, and the distal link element 11 are aligned parallel to one another. In Figure 7, a covering cover 38, which is only marginally visible in Figure 6, has been removed for illustrative purposes. In the perspective view according to Figure 7, the covering cover 38 would be located on the lower, flattened side.

Figure 8 first shows the further course of the actuation cable 31 for the distal pitch joint 10. Accordingly, after being guided by the pair of guide rollers 36, 37, it runs over the distal pitch joint 10 via a further guide roller 39 attached to the proximal link element 9.

The distal pitch joint 10 allows rotations of the distal

Link element 11 relative to the proximal link element 9 by a Rotation axis, which runs perpendicular to the plane of the drawing in Figure 2. A comparison of the angular position of the distal link element 11 relative to the proximal link element 9 shows that in Figure 8, the action of the actuating cable 31 in cooperation with the distal pitch joint 10 has caused a deflection of the distal link element 11 relative to the proximal link element 9. Due to the orientation of the rotation axis of the distal pitch joint 10, the deflection is a pitch movement.

Figures 7 and 8 also show a further actuation cable, namely the actuation cable 40 for the distal yaw joint 41. The actuation cable 40 for the distal yaw joint 41 runs from the cable guide bore 19 in the base shaft via the robot arm 4 back to the cable guide bore 18. It is initially guided horizontally offset parallel to the actuation cable 31 for the distal pitch joint 10 via a triplet consisting of guide pulleys, of which only the guide pulley 42 can be seen, and a deflection pulley 43 on the side of the proximal joint 8 as well as guide pulleys 44, 60 on the side of the proximal link element 9, which runs on the same axis as the guide pulley 37 for the actuation cable 31 and for the distal pitch joint 10.

Furthermore, the actuation cable 40 is deflected via guide rollers 55, 56 perpendicular to the plane according to Figure 2 in order not to collide with the actuation cable 31 for the distal pitch joint 10.

Further on, the actuation cable 40 for the distal yaw joint 41 is guided over the distal pitch joint 10 and a pulley 47 over the distal yaw joint 41 of the distal link element 11. Dedicated pulleys are also located here to reduce cable friction. The mode of operation of the distal yaw joint 41 in interaction with the actuation cable 40 for the distal yaw joint 41 can be seen particularly well in Figure 9. This shows the object from Figure 8 rotated by 90° from the drawing plane according to Figure 8 in a viewing direction along the arrow IX in Figure 8. Figure 9 shows the complete guidance of the actuation cable 40 via a triplet 48 consisting of a main deflection pulley 43 and a pair of guide pulleys 42, 61 arranged to form an equilateral triangle as well as further guide pulleys 44, 60 towards the distal yaw joint 41. The rotation axis of the distal yaw joint 40 is at an axial angle of 90° to the rotation axis of the distal pitch joint 10. The rotation axis of the distal pitch joint 10 is in turn at an axial angle of 90° to the rotation axis of the proximal joint 8.

As illustrated in Fig.9, the actuation cable 40 for the distal yaw joint 10 is guided to the distal link element 11 via the guide rollers 61, 43, 60, 45, 46, 81, 84.

As shown in Fig. 7, the actuation cable 40 is guided through the through-hole 84 and, as shown in Fig. 9, is fixed by means of a screw-clamp connection 83 to ensure frictional connection. The actuation cable 40 is then guided via the guide rollers 47, 80, 56, 55, 44, 43, 42 back to the control box 3 arranged behind the robot arm 4.

Figure 9a shows the object from Figure 8 rotated by 90° from the drawing plane according to Figure 8 in a viewing direction along the arrow IXa in Figure 8. The representation corresponds in this respect to that of Figure 9, but a section along the line IXa - IXa is shown in Figure 8. Figure 9a shows the fixation points 82 for the distal pitch joint 10. For fixation, the actuation cable 31 can be cut and knotted here, for example. The larger diameter of the knot (which is not shown in Figure 9a for better visibility) prevents the actuation cable 31 from slipping. However, other fixation methods are also conceivable, such as clamping or gluing.

Thus, yaw and pitch movements can be performed with the robot arm 4 using the rotation axes. Distally, the distal

Link element 11 is enclosed by two fork elements. One fork also functions as an end effector flange and has various threads and fitting holes for attaching the respective instruments to the end of the robot arm 4.

To detect the position of each individual pivot joint 8, 10, 41, a Hall sensor is located concentrically above each rotation axis (not visible in the figures). The Hall sensor measures the rotation via a magnet embedded in the rotation axis. The Hall sensor data is transmitted to the control box 3 via a flexible sensor circuit board 21 along the base shaft 5.

The structure of the robot arm 4 can be scaled so that it can be dimensioned for different applications, whereby the basic principles remain the same in each case.

In the manner described, the different joint types and their sequence form the main character of the endoscopic robot 1 according to the invention. The distances between the individual joints can be varied to achieve maximum accessibility of components in the object to be inspected. Robot arm 4 is basically designed as RP+RRR kinematics.

The first two degrees of freedom RP - rotation and prismatic - are provided by the support system 2 through a rolling movement around the axis of the base shaft 5 and a translation along the axis of the base shaft 5.

The first subsequent rotational degree of freedom is oriented radially to the axis of base shaft 5. The subsequent degree of freedom is also oriented radially to the axis of base shaft 5, but offset by 90° from the first. The last degree of freedom is again oriented parallel to the first endoscopic degree of freedom. The first two degrees of freedom (RP) are subject to the assumption that there are external constraints due to a maintenance entrance of the object to be inspected, which does not allow any further degrees of freedom.

The endoscopic robot 1 described above, with the robot arm 4, can be used for inspection in a variety of application fields. For example, tanks, containers, and high-pressure vessels can be endoscopically inspected, for example, when they are pressurized or filled with critical materials such as pharmaceutical products. An endoscopic view of the interior of these objects is generally informative for determining the condition of welds or similar.

The disclosed endoscopic robot 1 with the robot arm 4 can be used at various stages. It is suitable as a research tool, in quality control, and as a maintenance tool throughout the entire life cycle of an object to be inspected.

The disclosed endoscopic robot 1 or the robot arm 4 can be attached to a Cartesian traversing system, which is located in a container. In this way, the endoscopic robot 1 can be positioned and inserted through the inlets of a pressure tank. This enables rapid and repeatable inspection, for example, for carrying out inspections on a tank container system.

LIST OF REFERENCE SYMBOLS

1 Endoscopic robot

2 carrier system

3 Control box

4 Robot arm

5 Base shaft

6 proximal end of the base shaft

7 distal end of the base shaft

7a . Middle section of the base shaft

8 proximal joint

9 proximal limb element

91 Through hole

10 distal pitch joint

11 distal limb element

12 recess

13 Recording recess

14 Recording recess

15 Cable guide hole for proximal link element

16 Cable guide hole for proximal link element

17 Cable guide hole for distal link element, yaw movement

18 Cable guide hole for distal link element, pitching movement

19 Cable guide hole for distal link element, pitching movement

20 Cable guide hole for distal link element, yaw movement

21 Sensor circuit board

22 cap

23 Actuation cable for the proximal joint

24 guide groove

25 f

26 axis of rotation

27 Outer contour 28 lever arm

29 rolling bearings

30 axis of rotation

31 Actuation cable for the distal pitch joint

32 triplet

33 Main pulley

34 Guide roller

35 Guide roller

36 Guide roller

37 Guide pulley

38 Fairing cap

39 Guide pulley

40 Actuation cable for the distal yaw joint

41 distal yaw joint

42 Guide pulley

43 Main pulley

44 Guide roller

45 Guide roller

46 Guide roller

47 pulley

48 triplet

49 trough

50 trough

51 Fork part

52 Fork part

53 Guide channel

54 Fixation point

55 Guide pulley

56 Guide roller

57 60 guide roller

61 Guide pulley

70 Deflection pulley 71 Deflection pulley

82 fixation points

83 screw-clamp connection

84 Through hole

Claims

PATENT CLAIMS 1. Robot device (1, 4) for endoscopic inspections, with a preferably elongated base shaft (5) and at least one link element (9, 11) mounted so as to be rotatable by an angle and having adjusting means (23, 31, 40) for varying the angle, characterized in that a joint element (8, 10, 11) is provided, with which the at least one link element (9, 11 ) is mounted in such a way that it can rotate about exactly one axis of rotation (30). 2. Robot device (1, 4) according to the preamble of claim 1, characterized in that the base shaft (5) has at least one recess (12) in cross section on an outer side. 3. Robot device (1, 4) according to claim 1 or 2, characterized in that two or more link elements (9, 11) are provided, which are each rotatably mounted relative to the base shaft (5) and/or relative to a further link element (9, 11). 4. Robot device (1, 4) according to one of the preceding claims, characterized in that at least one link element (9, 11) is attached to the base shaft (5) and/or to another link element (9, 11) in such a way that a lever arm (28) is formed between the axis of rotation (30) and an outer contour of the link element (9, 11). 5. Robot device (1, 4) according to one of the preceding claims, characterized in that at least one link element (9, 11) is rotatable about an axis of rotation (30) of a further link element (9, 11) is rotatably mounted on a rotational axis (30) arranged at an axial angle, wherein the axial angle is preferably 90°. 6. Robot device (1, 4) according to one of the preceding claims, characterized in that the adjusting means (23, 31, 40) comprise a, preferably antagonistic, cable pull. 7. Robot device (1, 4) according to one of the preceding claims, characterized in that cable guide means (24, 25, 32, 33, 34, 35, 36, 37, 39, 42, 43, 44, 45, 46, 47) are provided for guiding and/or deflecting the cable pull. 8. Robot device (1, 4) according to one of the preceding claims, characterized in that the cable guide means (24, 25, 32, 33, 34, 35, 36, 37, 39, 42, 43, 44, 45, 46, 47) comprise at least one deflection pulley. 9. Robot device (1, 4) according to one of the preceding claims, characterized in that the cable guide means (24, 25, 32, 33, 34, 35, 36, 37, 39, 42, 43, 44, 45, 46, 47) comprise at least one triplet (32) of three deflection pulleys, the axes of rotation of which are aligned parallel to one another and are arranged in a plane in the shape of an isosceles triangle, the base of the isosceles triangle being arranged at the proximal end of the cable guide. 10. Robot device (1, 4) according to one of the preceding claims, characterized in that angle sensor means are provided to determine the angle of the link element (9, 11). measure, wherein in particular each joint element (8, 10, 11) is assigned angle sensor means. 11. Robot device (1, 4) according to one of the preceding claims, characterized in that the joint element (8, 10, 11), preferably on both sides, is provided with stop means in order to limit an angular stroke of the angle. 12. Robot device (1, 4) according to one of the preceding claims, characterized in that separate adjusting means (23, 31, 40) are assigned to each link element (9, 11). 13. Robot device (1, 4) according to one of the preceding claims, characterized in that the base shaft (5) has a substantially circular and/or oval cross-section. 14. Robot device (1, 4) according to one of the preceding claims, characterized in that the recess (12) has the shape of a circular segment in cross section. 15. Robot device (1, 4) according to one of the preceding claims, characterized in that the adjusting means (23, 31, 40) and/or data lines are arranged to run in a radially inner region of the cross section of the base shaft. 16. Robot device (1, 4) according to one of the preceding claims, characterized in that the adjusting means (23, 31, 40) are arranged in a radially inner region of the base shaft (5). 17. Robot device (1, 4) according to one of the preceding claims, characterized in that the base shaft (5) has bores extending in the longitudinal direction for the passage of the adjusting means (23, 31, 40). 18. Robot device (1, 4) according to one of the preceding claims, characterized in that the base shaft (5) is provided on its distal end face with receiving means for receiving the joint element (8, 10, 11). 19. Robot device (1, 4) according to one of the preceding claims, characterized in that the base shaft (5) is made of a rigid material, preferably titanium. 20. Robot device (1, 4) according to one of the preceding claims, characterized in that the base shaft (5) is operatively connected at its proximal end to actuating means for driving the adjusting means (23, 31, 40). 21. Robot device (1, 4) according to one of the preceding claims, characterized in that covering means are provided for covering the recess (12), wherein the covering means are preferably designed to be plugged onto the base shaft (5). 22. Robot device (1, 4) according to one of the preceding claims, characterized in that the base shaft (5) is connected to a translationally and/or rotationally movable support system, in particular to a collaborative lightweight robot and/or a cobot.