Medical device, method for operating a medical device, computer program and data carrier

Abstract

The present invention relates to a medical device comprising: a functional component, a carrier device arranged for positioning the functional component in space, the carrier device carrying the carrier component, an additional component positioned and / or shaped in different ways in different positions of the carrier device, a control device comprising: a model unit for updating a digital motion model of the medical device based on position data indicating the current position of the carrier component, the model unit mapping the carrier component and the functional component and their mobility, a detection unit for evaluating the current motion model to detect a possible collision with at least one subject and / or object located within a range of motion and mapped in the motion model, and a measure unit for executing at least one collision protection measure when an impending collision is detected, wherein the motion model also maps the movement of the additional component, the model unit being configured to determine additional data describing the current posture and / or shape of the additional component by associating at least part of the position data with the additional data.

Description

Technical Field

[0001] The present invention relates to a medical device comprising:

[0002] - at least one functional component,

[0003] - a carrier device (or carrier device) is provided for positioning the functional component in space, the carrier device having at least two carrier components that can move relative to each other,

[0004] at least one additional component which is positioned and / or shaped differently in different locations of the carrier device,

[0005] - control equipment,

[0006] In order to form a collision protection system, the control device includes:

[0007] a model unit for updating a digital kinematic model of the medical device based on position data showing the current position of the carrier component, the model mapping (or imaging, displaying) the carrier component and the functional components and their movability,

[0008] a detection unit for evaluating the current motion model to detect a possible collision with at least one subject and / or object located within the motion range and mapped in the motion model, and

[0009] A measures unit for executing at least one collision protection measure upon detection of a possible imminent collision.

[0010] Furthermore, the invention relates to a computer-implemented method, a computer program and an electronically readable data carrier for operating such a medical device. Background Art

[0011] Medical devices, particularly those used for examining and treating patients, often have movable components that are intended to avoid collision with the patient or other detectable objects, particularly other components of the medical device. Such medical devices typically have at least one functional component that can be positioned in space via a carrier device having a carrier component for proper examination and / or treatment of the patient. For example, such a functional component can be a recording device in the case of medical imaging devices or a radiation head in the case of radiotherapy devices.

[0012] This problem is particularly relevant in X-ray systems that have a recording device with an X-ray emitter and an X-ray detector that can be freely positioned in space. This allows for different projection directions or, in general, recording geometries that correspond to the medical procedure to be performed. Typically, such X-ray systems have a C-crank arm, on which the X-ray emitter and X-ray detector are arranged relative to each other. The C-crank arm forms a carrier assembly. It can be movably held in an outer arm by a support (e.g., a pulley), for example, to enable orbital rotation as a degree of freedom of movement, with the support forming another carrier assembly. The outer arm can also be partially referred to as an (external) telescopic C-crank arm, while the actual C-crank arm is referred to as an inner C-crank arm. Other designs of such X-ray systems with a C-crank arm, as well as methods for independently moving the X-ray emitter and X-ray detector, can also include a robotic arm. Such X-ray systems are also commonly referred to as angiography systems, in particular robotic angiography systems, and are typically used, in particular, during minimally invasive surgery on patients, generally during clinical interventions.

[0013] A common observation for medical devices is that the more conservatively designed the collision protection system is, the more significantly it restricts the free range of motion for functional components. This means that certain treatment and / or examination positions, such as imaging geometries in imaging devices, may not be possible due to the collision protection system, even though they would be possible if the collision protection system were to function more accurately. High-precision collision protection systems that maximize the free range of motion often come at the cost of high costs and complexity, meaning they are highly complex.

[0014] Collision protection systems have been proposed in the prior art that use distance sensors on the functional components and / or carrier components of the carrier device, but these are expensive and complex in terms of design, data evaluation, and control. Therefore, software-based collision protection systems (e.g., using the position data of the carrier components already available in the control unit of the medical device) are more cost-effective and easier to implement, and are therefore preferred. Software-based collision protection systems also allow for faster movement of the carrier components relative to one another by avoiding blind spots, such as those created by sterile covers, and can even assess penetration depths to allow for quick resolution of collision situations.

[0015] For example, collision protection systems have been proposed that continuously monitor the movement of the medical device using a motion model and prevent collision-related hazards by limiting the system's speed. For distance calculation, the medical device can be divided into a finite number of rigid geometric elements in the motion model, whose spatial posture (i.e., position and orientation) can be detected in the motion model using a kinematic chain. In addition to the medical device, other objects and / or subjects can also be detected in the motion model, in particular those with which collision is undesirable. In many embodiments, this primarily involves the patient as the subject.

[0016] DE 11 201 7 000 642 T5 discloses a device for detecting a possible collision during a medical procedure. The device comprises a camera for capturing an image of a patient lying on a patient support and a processing unit. The processing unit is configured to determine, at least in part based on the image, a first model, wherein at least a portion of the first model represents the surface of the patient, and a second model, wherein the second model represents a first component of a medical system, and to provide a collision prediction mechanism for virtual movement of the first model, the second model, or both. The collision prediction mechanism is configured to simulate the movement of the first component of the medical system to determine whether a collision is likely to occur between the first component and the patient. The collision prediction mechanism is further configured to generate an output signal indicating a possible collision or an unlikely collision.

[0017] DE 102 00 534 A1 discloses a method for collision-free movement of at least two objects that can be moved relative to one another, in particular as components of medical examination and / or treatment equipment. A three-dimensional simulated view of the objects is displayed on a monitor in their current rest position. The objects are then moved relative to one another within the framework of the simulation and, under continuous viewing of the simulated positions, to a desired simulated target position. After automatically determining a collision-free movement path in advance, the real objects are then automatically moved to the target position assumed in the simulation.

[0018] For cost reasons and to reduce complexity, only the degrees of freedom of motion of the carrier device that are directly related to the positioning of the patient and functional components are typically mapped or reflected in the kinematic model. These degrees of freedom of motion have the advantage that the sensors of the actuators used for the relative movement of the carrier components usually already provide sufficient position data. However, this leads to the problem that some additional components of the medical device, such as cable guide components with rotatable cable outlets, cannot be understood in the kinematic model despite at least partial changes in their posture and / or shape when the carrier device is modified, because no position data is available for this purpose. Accordingly, the prior art proposes to map such additional components using larger geometric model elements of the additional component, which cover the entire conceivable free range of motion of the additional component. However, such larger, "expanded" model elements are disadvantageous because, if necessary, clinically relevant positions cannot be achieved, or at least not in the shortest possible time. Summary of the Invention

[0019] The object of the present invention is to provide a collision protection concept which increases the available positioning space for functional components but reliably prevents collisions.

[0020] The above-mentioned technical problem is solved according to the invention by a medical device, a method, a computer program and an electronically readable data carrier according to the independent claims. Advantageous embodiments are disclosed in the dependent claims.

[0021] In a medical device of the type mentioned at the outset, it is provided according to the invention that the movement model also maps the movement of the additional component, wherein the model unit is designed to determine additional data describing the current posture and / or shape of the additional component from a correlation of at least part of the position data stored in the control device with the additional data.

[0022] The present invention is based on the recognition that in many cases there is a decisive or deterministic relationship between the movement of a carrier component and, in particular, an additional component connected thereto, which can be exploited to at least partially incorporate the additional component into the movement model and also map its movement, so as to avoid the appearance of enlarged geometric elements of an obstructed space. Therefore, in addition to better protecting the subject and / or object from collisions, the improved movement model also provides a greater freedom of movement, so that examinations and / or treatments can be carried out in a wider range of clinically relevant positions using functional components, thereby improving the quality of the examinations and / or treatments, in particular the quality of medical interventions. As will be explained in more detail below, the improvement can be carried out in particular using existing components of the collision protection system, in particular the movement model, without requiring significant changes to the existing software structure. In particular, no additional, complex and / or expensive additional sensor technology associated with the additional component is required.

[0023] The improved design of the software-based collision protection system according to the present invention overcomes the limitations on the free range of motion in clinically relevant positions caused by uncertainties in the pose (position and orientation) and / or shape of additional components by establishing a deterministic link between the movement of the additional components and the existing position data. This significant improvement replaces the previously used enlarged model elements with more precise geometric representations and poses / shapes, thereby expanding the accessibility of clinically relevant areas of interest without the need for complex and expensive position sensors. The present invention also allows for rapid positioning of functional components, as the actual geometry is reproduced and the shortest possible collision-free movements are achieved.

[0024] In particular, it may be provided that the at least one additional component comprises at least one element of a cable guide assembly for connecting at least one cable to a functional component. To perform its function, a functional component typically requires at least one cable connection, such as a connection for electrical and / or other power sources and / or at least one data / communication line. Even if the carrier device includes carrier components that can move relative to each other, it is still necessary to guide the corresponding cables to the functional component. For this purpose, a cable guide assembly with a defined degree of mobility is typically used between at least two carrier components. Movement of the carrier components results in changes in the position and / or shape of the cable guide assembly and its components. At least one element of the cable guide assembly may be at least one rigid cable outlet, particularly a cable outlet for connecting to a corrugated tube / bellows, which, based on the aforementioned association, is considered an additional component in the kinematic model. For example, cable guide assemblies are known in the prior art that have two cable outlets rotatably mounted on each carrier component, connected flexibly and, if necessary, in length, via a corrugated tube. In this case, the cable outlets can be mapped as additional components in the kinematic model due to their rotatability, thereby avoiding the need for more complex integration of the corrugated tube.

[0025] This is because practice and experimentation have shown that collision problems are usually caused by the cable outlet, not the corrugated tube. Therefore, modeling the cable outlet, which is particularly easy to implement, is sufficient to significantly improve the quality of the kinematic model and thereby increase the free space for movement of the functional components. An embodiment is conceivable in which the additional component representing the cable outlet in the kinematic model is longer than the actual cable outlet, so that a portion of the corrugated tube can also be mapped, achieving further improvements.

[0026] In the example of a cable outlet as a (rotatable) additional component, but also in general, a suitable refinement of the present invention provides for the additional component to be incorporated into a kinematic model using at least one kinematic chain, particularly as a rigid, rotatably coupled kinematic element, using the Denavit-Hartenberg representation (DH representation). The kinematic chain allows for a particularly computationally efficient, uncomplicated, and easy-to-handle mapping of the carrier device in the kinematic model. It is now proposed that, even when at least one additional component is added, the fundamentally simple structure of the kinematic chain, consisting of rigid, particularly rotationally coupled kinematic elements, be maintained and incorporated into the kinematic chain using the DH representation commonly used herein. When coupled as a rigid, rotatably coupled kinematic element (which represents the cable outlet as an element of the cable guide assembly in the kinematic model), the additional data preferably specifies the angular position of the at least one kinematic element (and therefore of the cable outlet). This angular position can be understood as the cable outlet angle. In particular, the additional data can specify at least one angular position of the corresponding kinematic element (model element) of the additional component relative to the carrier assembly and / or functional assembly to which the element is connected. In the case where the cable outlet is rotatably coupled to the carrier component as an additional component and the rigid movement element, respectively, a zero position can be defined for the angle of the angular position, wherein the association then allows the corresponding angle to be determined from at least part of the position data. If the cable guide component is connected to two carrier components connected by a kinematic chain, in particular adjacent ones in the kinematic chain, then as part of the position data, position data that particularly describe the position of these carrier components relative to each other can be relevant, for example, the position angle of a C-crank arm when it is moved in an outer crank arm via a bracket (pulley).

[0027] It should be noted that, in general, but also in particular for the case of a cable guide element comprising a corrugated tube between the cable outlets, a more precise description can be achieved by using rigid segments coupled in a kinematic chain. Thus, for example, the corrugated tube can be modeled as a plurality of segments coupled to one another in rotation, in order to achieve improvements here as well. However, in the case of an X-ray device with a C-crank arm guided in an outer crank arm, in particular via a bracket (pulley) as a carrier component to which the cable outlet is attached, as previously mentioned, the corrugated tube contributes much less to the risk of collision and to the restriction of free space than the cable outlet, so that in this case the expenditure of additional model segments is not necessarily required. However, there are other cases in which this also appears to be suitable for significantly increasing the free space for movement of functional components.

[0028] As a further possibility for considering the corrugated tube, a model of a portion of the X-ray system's bed (i.e., the bedplate of the patient support) can also be used, enlarged, in particular along the edges surrounding the cylindrical shape. The specific combination of modeling the cable outlet with a local enlargement of the model representation of the bed has shown excellent results, with the bed being particularly an object or part of an object to be prevented from collision. The local enlargement of the bed is then not used generally, but only in conjunction with the modeled cable outlet. In other words, this means that the collision check between the bed and the cable outlet uses the local enlargement, but all other movement paths, in particular other objects and components of the X-ray system, remain unimpaired by this local enlargement. Thus, compared to conceivable methods that completely map the additional components (here, the corrugated tube and the cable outlet) and generally map the bed model as an extension, the free space for movement is not restricted but rather significantly expanded.

[0029] A medical device may, in particular, be an X-ray device having an imaging device as a functional component, the imaging device comprising an X-ray emitter and an X-ray detector. Such X-ray devices are typically used in the context of medical interventions and, because they can be used for a variety of medical procedures, are advantageous if a particularly large number of clinically relevant locations of the functional components, in this case the imaging geometry, can be reached, particularly in the shortest possible path. Therefore, the present invention can be used particularly advantageously in such X-ray devices as medical devices.

[0030] At least one support component can be a C-crank arm that is movably guided in an outer crank arm via a support, particularly a pulley, as a further support component. Its position relative to the support is specified in the position data by a position angle. For an element, particularly a cable outlet, of a cable guide assembly, which is an additional component and guides cables from the support to a functional component arranged on the C-crank arm, the association assigns additional data, particularly the angular position of the cable outlet modeled as a rigid element, to the position angle. The C-crank arm is guided in the outer crank arm via the support, such as a pulley, as the support component, because the arc lengths of the (inner) C-crank arm and the outer crank arm (external telescopic C-crank arm) differ significantly. The support can be moved along both arcs with different (but fixed) transmission ratios. Therefore, it can be provided that, when the cable guide assembly is fixed to the C-crank arm and the support movably connecting the C-crank arm to the outer crank arm, the additional data specifies the angular position of the respective cable outlet as an additional component relative to the respective support component (C-crank arm, support).

[0031] In this specific embodiment, a deterministic correlation between the angular position of the cable outlet and the position angle of the C-crank arm is utilized. This correlation exists due to the consistent mechanical properties of the fixed-length corrugated tube and this type of X-ray device with a C-crank arm. Due to the defined mechanical coupling achieved by the support, the position angle can also be used, in particular, as the orbital angle (the position angle between the outer and C-crank arms), which also describes the relative position of the C-crank arm and the support. The cable outlet can be modeled, in particular, as a kinematic element with a rotation angle that depends solely on the known position angle, in particular the orbital angle. The additional information obtained through this correlation resolves uncertainties, and the cable outlet model can be reduced to its actual geometry. The expanded kinematic configuration can advantageously map the cable outlet motion using new rotatably coupled model elements using the Denavit-Hartenberg representation (DH representation). These elements are advantageously integrated into the kinematic chain as additional components in a minimally invasive manner to model the carrier device. The angular position of the cable outlet determined by this correlation is introduced into the kinematic chain to trigger an update of the kinematic model for accurate distance calculation.

[0032] In a preferred embodiment, the association can be stored as a lookup table, wherein the model unit is configured to determine the additional data by interpolation for values ​​of the position data that lie between the table values ​​in the lookup table. Basically and generally speaking, it is conceivable to store the association as a lookup table in a memory device of a control device for the model unit in an implementation-friendly manner, for example, based on the results of calibration measurements. Of course, other embodiments are also conceivable to store the association as a mathematical function, for example, determined by fitting. In the case of a lookup table, it is particularly advantageous to interpolate the values ​​of the position data that lie between the table values ​​in the lookup table to determine the corresponding additional data. Linear interpolation is particularly used in this context.

[0033] To determine at least some of the position data, the medical device can have at least one sensor associated with the actuator. This is particularly advantageous in that additional sensor equipment for determining the position data can be completely omitted. Preferably, the current position of the actuator, and thus the current position of the carrier components relative to one another, is already tracked in the control unit of the medical device. Ideally, corresponding sensor feedback from the actuator can be used for this purpose.

[0034] As previously mentioned, the collision protection of the collision protection system specifically concerns the patient as the subject. The patient can be easily incorporated into the kinematic model, for example, using cylindrical modeling. This is because the patient's usual position on the bed associated with the medical device, as determined more precisely from process data, is generally known. Similarly, the bed or the entire patient support, considered as the object to be protected from collision, is also tracked in the control unit, for example with respect to its actuators and adjustment options. Thus, both the patient support with the bed as at least one subject and the patient as the subject can be easily incorporated into the kinematic model without requiring complex additional sensor systems or the like. The detection unit can thus be designed to use at least one patient, particularly at least partially modeled as a cylinder, as the subject, and / or a patient support, particularly forming part of the medical device, as the subject. Furthermore, other objects and / or subjects can, of course, also be incorporated into the kinematic model if they can be mapped, particularly in a simple and appropriate manner, in a posture that at least approximately corresponds to reality.

[0035] In designs for X-ray equipment, as well as for other medical equipment, the carrier device is preferably mounted on the ceiling. Mounting the carrier device on the ceiling provides greater freedom for equipment, personnel, and their movement in the area close to the ground, which is particularly advantageous for medical interventions, such as minimally invasive interventions. Of course, mounting the carrier device on the floor is also conceivable.

[0036] As a collision protection measure, a signal indicating a possible impending collision may be output. As a collision protection measure, for example, provision may also be made for the movement of at least one carrier component to be slowed down and / or stopped, and / or for a warning to be issued, and / or for an alternative travel path to be determined and used in order to reach the target position of the functional component.

[0037] In addition to a medical device, the present invention also relates to a computer-implemented method for operating a medical device, in particular a medical device according to the present invention, wherein the medical device has:

[0038] - at least one functional component,

[0039] - a carrier device is provided for positioning the functional component in space, said carrier device having at least two carrier components that can be moved relative to one another,

[0040] at least one additional component which is positioned and / or shaped differently in different locations of the carrier device,

[0041] a control device which, for the purpose of collision protection, uses the position data indicating the current position of the carrier component to update a digital motion model of the medical device that maps the carrier component and the functional components together with their movability, evaluates the current motion model to detect a possible collision with at least one subject and / or object located within a range of motion and mapped in the motion model, and executes at least one collision protection measure upon detection of a possible collision,

[0042] The movement model also maps the movement of the additional component, wherein additional data describing the current posture and / or shape of the additional component are determined from a linking of at least part of the position data with the additional data stored in the control device.

[0043] All statements regarding the medical device according to the invention are transferable analogously to the computer-implemented method according to the invention, so that the advantages described above can also be achieved by this method.

[0044] The computer program according to the invention can be directly loaded into a memory device of a control unit of a medical device and has program means for carrying out the steps of the method according to the invention when the computer program is executed on the control unit. The computer program can be stored on an electronically readable data carrier according to the invention, which includes control information stored thereon, including at least one computer program according to the invention and is designed to configure the data carrier to carry out the method according to the invention when used in a control unit of a medical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Further advantages and details of the present invention are apparent from the following exemplary embodiments and the accompanying drawings, in which:

[0046] Figure 1 A schematic diagram showing a medical device according to the invention configured as an X-ray device,

[0047] Figure 2 shows the functional structure of the control device of the X-ray device,

[0048] Figure 3 A diagram showing a first cable outlet in a kinematic model,

[0049] Figure 4 A diagram showing a second cable outlet in a kinematic model,

[0050] Figure 5 shows a diagram representing the association between position data and additional data,

[0051] Figure 6 An exemplary process flow diagram of the method according to the present invention is shown. DETAILED DESCRIPTION

[0052] Figure 1 An X-ray device 1 is shown as an embodiment of a medical device according to the present invention. It comprises a top-mounted carrier device 2 with multiple carrier components that can move relative to each other to generate different degrees of freedom of movement. For example, a support plate 4 can be moved within a rail system 3. An arm 5 is rotatably mounted on the support plate 4 relative to the support plate 4. An outer curved arm 6 is rotatably mounted on the arm 5. A C-curved arm 7 is movably supported in the outer curved arm by a bracket 32, such as a pulley, to adjust the track angle. Due to the different arc lengths of the C-curved arm 7 and the outer curved arm 6, the bracket moves in the two curved arms 6 and 7 with different fixed transmission ratios. An X-ray emitter 8 and an X-ray detector 9 are arranged relative to each other on the C-curved arm 7, forming an imaging device as a functional component.

[0053] The X-ray device 1 also includes a patient support 10, which is only shown schematically here, with a bed 11 for a patient 12, from which X-ray images of the patient can be recorded from different positions of the recording device, in particular different recording geometries, during medical procedures, in particular during examinations and / or treatments.

[0054] Here, the cables for power supply and / or data communication with the X-ray emitter 8 and the X-ray detector 9 are initially guided concealedly through the arm 5 and then through a flexible, crash-independent corrugated tube (or bellows) to the bracket 32 ​​on the outer curved arm 6. However, due to the relative mobility of the bracket 32 ​​and the C-crank arm 7, a cable guide assembly 13 is used to guide the cables further to the C-crank arm 7. The cable guide assembly 13 includes two rigid cable outlets 14, which are rotatably arranged on the respective carrier components, namely the bracket 32 ​​and the C-crank arm 7. The two rigid cable outlets are connected by a flexible corrugated tube 15. If the C-crank arm 7 moves in the bracket 32, the angular position of the cable outlet 14 relative to the bracket 32 ​​or the C-crank arm 7 changes, causing the corrugated tube 15 to deform.

[0055] It is generally known that the operation of the X-ray device 1 is controlled by a control device 16 having at least one processor and at least one memory device, which is also designed to carry out the method according to the invention.

[0056] In particular, a crash protection system is formed in the control device 16 , which uses a kinematic model, wherein the cable outlet 14 is also mapped as an additional component, ie, a rotationally coupled rigid element, as will be explained in detail below.

[0057] Figure 2First, a functional schematic diagram of the control device 16 is shown. In addition to the aforementioned storage device 17 and other functional units, of which the recording unit 18 is shown purely by way of example, the collision protection system 19 also has at least one model unit 20. The model unit 20 uses the current position data of the carrier device 2, which are obtained from the corresponding actuators assigned to the respective degrees of freedom of movement. Figure 1 Sensors (not shown in greater detail) are provided via interfaces to the control unit 16 in order to update the motion model of the X-ray system 1, in which the patient 12 is also represented as a subject, for example as a cylinder, optionally with an additional safety zone. The carrier assembly is thus represented as part of a kinematic chain in a particularly uncomplicated and user-friendly manner.

[0058] However, here the kinematic configuration extends beyond the carrier device 2, since the cable outlet 14 is also added as an additional component, which is virtually displayed using the Denavit-Hartenberg representation (DH representation) as a model element that is rigidly and rotatably coupled to the corresponding carrier components, here the bracket 32 ​​and the C-arm.

[0059] This is achieved through Figure 3 and Figure 4 To explain in more detail, Figure 3 and Figure 4 A schematic diagram of a detail of a kinematic model 21 is shown in each case, which for reasons of clarity is limited to the respective carrier component and the additional components kinematically coupled thereto, namely the respective cable outlet 14 . Figure 3 and Figure 4 A kinematic element 22 representing the cable outlet 14 is shown in a zero position 23 by a solid line, which corresponds to an angular position of 0°. Element 22 is coupled to a corresponding support component (support 32 / C-crank arm 7) or a model element representing the support component so that it can rotate about an axis of rotation 24 extending perpendicular to the plane of the drawing. A further angular position 25 and the corresponding direction 26, along which the angle is illustrated, are indicated by a dashed line.

[0060] The cable outlet 14 is modeled as a kinematic element 22 that can rotate relative to the corresponding carrier element. Therefore, it does not need to be mapped in an exaggerated manner based on its basic mobility, but can be reduced to its actual geometry. Integration into the kinematic chain using the DH representation allows for a minimally diffuse integration into the kinematic model 21. Only the rigid, easily mapped cable outlet 14 is incorporated into the kinematic model 21, as it has been shown to be primarily relevant for collision protection and for expanding the free space for movement of the camera as a functional component. However, in fully conceivable embodiments, the corrugated tube 15 is also modeled, for example, using rotatably connected rigid subsegments.

[0061] In order to be able to update the movement model 21 with respect to the movement of the cable outlet 14, its angular position 25 must be determined. It has already been shown that there is a deterministic relationship between the partial position data (here specifically the track angle) and the angular position 25 (as additional data based on the additional component). The track angle is therefore used as a position angle to describe the position of the C-arm 7 to the support 32. This relationship can be determined, for example, in a calibration measurement and allows the determination of the position angle according to the cable outlet 14 only from the knowledge of the track angle that can actually be determined from the data of the at least one sensor of the relevant at least one actuator. Figure 3 and Figure 4 The angular position 25 of the corresponding cable outlet 14 is defined. The angular position 25 of the cable outlet 14 is then introduced into the kinematic chain to trigger an update of the kinematic model 21 .

[0062] Figure 5 This relationship is shown, for example, by means of a diagram in which the corresponding angular position is plotted as angle (a) relative to the orbital angle (o). Figure 3 The angle relative to the C-bend 7 is shown in FIG. 2 , and the curve 28 represents Figure 4 The angles relative to the support 32 are shown in FIG. The curves 27, 28 can be obtained, for example, from calibration measurements.

[0063] This association is preferably stored as a lookup table 29 in the memory device 17, see Figure 2 In this lookup table 29, the corresponding angular positions 25 of the two cable outlets 14 are assigned to different table values ​​of the track angle, along with the angles (a and o). The model unit 20 can be designed to find corresponding intermediate positions for values ​​of the track angle that lie between the table values, in particular by linear interpolation.

[0064] In addition, based on Figure 2 The collision protection system 19 also has a detection unit 30, which evaluates the current motion model 21 and, if necessary, the motion model over past time periods as a motion history to check whether a collision is imminent. In this case, in particular, the patient 12 and the patient support table 10 are regarded as potential collision objects. In particular, the distance or distance change of the carrier component and the functional component to the object of the main body or the patient support table 10 can be taken into account, and if necessary, the penetration depth can also be estimated. When a possible collision is detected, the measure unit 31 performs at least one collision protection measure. This can be the output of a signal indicating a possible collision. It can also include braking, stopping and / or avoiding, and outputting warnings or information.

[0065] For the detection unit 30 and the measurement unit 31 , designs which are essentially known from the prior art can be selected.

[0066] Figure 6Finally, a flow chart of an exemplary embodiment of the method according to the present invention is shown, which can be executed by the control device 16. In this case, in step S1, the movement model 21 is continuously updated by the model unit based on the position data, wherein a correlation between at least part of the position data, in particular the orbital angle, and the additional data (here the angular position 25) is used to determine the current angular position 25 of the cable outlet 14 and is updated not only with respect to the carrier device 2 but also with respect to the cable outlet 14, as described above.

[0067] As already mentioned, the movement model 21 is generally updated whenever new position data are available, in particular triggered by the occurrence of a change, or cyclically updated.

[0068] In step S2, the detection unit 30 then checks whether a collision is imminent, here with the patient 12 or the patient support 10. If a collision is detected in step S3, appropriate collision protection measures are initiated by the measures unit 31 in step S4, as described above.

Claims

1. A medical device comprising: - at least one functional component, - a carrier device (2) is provided for positioning the functional component in space, said carrier device having at least two carrier components that can be moved relative to each other, at least one additional component which is positioned and / or shaped differently in different positions of the carrier device (2), - a control device (16), in, In order to form a collision protection system (19), the control device (16) comprises: - a model unit (20) for updating a digital kinematic model (21) of the medical device based on position data indicating the current position of the carrier component, said kinematic model mapping the carrier component and the functional components and their movability, a detection unit (30) for evaluating the current motion model (21) to detect a possible collision with at least one subject and / or object located within the motion range and mapped in the motion model, and a measures unit (31) for executing at least one collision protection measure upon detection of a possible impending collision, The invention is characterized in that the movement model (21) also maps the movement of the at least one additional component, wherein the model unit (20) is designed to determine additional data describing the current posture and / or shape of the at least one additional component from an association of at least a portion of the position data stored in the control device (16) with the additional data.

2. The medical device according to claim 1, characterized in that The at least one additional component comprises at least one element of a cable guiding assembly (13) for at least one cable.

3. The medical device according to claim 2, characterized in that At least one element of the cable guide assembly (13) includes at least one rigid cable outlet (14).

4. The medical device according to claim 1, characterized in that The at least one additional component is added to a kinematic model (21) using at least one kinematic chain by means of a Denavit-Hartenberg representation.

5. The medical device according to claim 4, characterized in that The additional data specify an angular position (25) of at least one kinematic element (22).

6. The medical device according to claim 1, characterized in that The medical device is an X-ray device (1) having a photographing device as a functional component, wherein the photographing device comprises an X-ray emitter (8) and an X-ray detector (9).

7. The medical device according to claim 6, characterized in that At least one carrier component is a C-crank arm (7) which is movably guided in an outer crank arm (6) via a bracket (32) as a further carrier component, and its position relative to the bracket (32) is specified in the position data by a position angle, wherein, for an element of a cable guide component (13) which is an additional component and guides a cable from the bracket (32) to a functional component arranged on the C-crank arm (7), the association assigns additional data to the position angle.

8. The medical device according to claim 7, characterized in that In the case where the cable guide assembly (13) is fixed to the C-bend arm (7) and the bracket (32), the additional data describes the angular position (25) of the corresponding cable outlet (14), which is an additional component relative to the corresponding carrier assembly.

9. The medical device according to claim 1, characterized in that The association is stored as a lookup table (29), wherein the model unit (20) is designed to determine the additional data by interpolation for values ​​of the position data (29) that lie between the table values ​​in the lookup table (29).

10. The medical device according to claim 1, characterized in that The medical device has at least one sensor assigned to the actuator for determining at least some of the position data.

11. The medical device according to claim 1, characterized in that The detection unit (30) is designed to use at least one patient (12) as a subject and / or a patient support table (10) as an object.

12. The medical device according to claim 3, characterized in that The rigid cable outlet (14) is a cable outlet for connecting to the corrugated tube (15).

13. The medical device according to claim 4, characterized in that The at least one additional component acts as a rigid, rotatably coupled kinematic element (22).

14. The medical device according to claim 7, characterized in that The element is a cable outlet (14).

15. The medical device according to claim 11, characterized in that The detection unit (30) is designed to use at least one patient (12) modeled at least partially as a cylinder as a subject and / or a patient support table (10) forming part of a medical device as an object.

16. A computer-implemented method for operating a medical device, the medical device comprising: - at least one functional component, - a carrier device (2) is provided for positioning the functional component in space, said carrier device having at least two carrier components that can be moved relative to each other, at least one additional component which is positioned and / or shaped differently in different positions of the carrier device (2), - a control device (16), The method includes: - for collision protection, using the position data indicating the current position of the carrier component by the control device to update a digital kinematic model (21) of the medical device that maps the carrier component and the functional components together with their movability, - evaluating the current motion model (21) by means of the control device to detect a possible collision with at least one subject and / or object located within the range of motion and mapped in the motion model (21), - executing at least one collision protection measure by the control device upon detection of a possible imminent collision, The movement model (21) also maps the movement of the at least one additional component, wherein additional data describing the current posture and / or shape of the at least one additional component are determined by an association of at least a portion of the position data stored in the control device (16) with the additional data.

17. A computer program which, when executed on a control device (16), performs the steps of the method according to claim 16.

18. An electronically readable data carrier on which the computer program according to claim 17 is stored.

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