Abstract:
The invention relates to an x-ray C-arm apparatus comprising an x-ray C-arm and a control facility that moves the x-ray C-arm in at least one rotational and/or translational degree of freedom depending on a control signal received. The x-ray C-arm apparatus features a user interface with a control element connected to the x-ray C-arm. The control element is connected to the user interface and enables it to be moved with at least one rotational and with at least one translational degree of freedom. The user interface detects the movement of the control element and creates the control signal depending on the movement of the control element, with the control signal representing at least the degree of freedom and/or a direction of movement of the control element, especially a direction of movement in the degree of freedom.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority of German application No. 10 2006 043 144.8 filed Sep. 14, 2006, which is incorporated by reference herein in its entirety. 
       FIELD OF THE INVENTION 
       [0002]    The invention relates to an x-ray C-arm apparatus. The x-ray C-arm apparatus features an x-ray C-arm and a control facility. The control facility is embodied to move the x-ray C-arm depending on a control signal received on the input side. 
       BACKGROUND OF THE INVENTION 
       [0003]    With x-ray C-arm apparatus known from the prior art the control facility is connected to a user interface, with the user interface featuring a control element embodied to allow movement and the control facility being embodied to detect a movement of the control element—for example by a user of the C-arm x-ray apparatus—and to generate the control signal depending on the movement of the control element. 
         [0004]    In this way a user can move the x-ray C-arm so that a movement of the x-ray C-arm is dependent on a movement of the control element. The user can thus control the C-arm indirectly by means of the control element. With x-ray C-arm apparatus known from the prior art the control element is embodied to enable it to swivel. 
       SUMMARY OF THE INVENTION 
       [0005]    The underlying object of the invention is to specify an x-ray C-arm apparatus with an improved control facility. This object is achieved by an x-ray C-arm apparatus which has an x-ray C-arm and a control facility. The control facility is embodied to move the x-ray C-arm in at least one rotational and/or translational degree of freedom depending on a control signal received on the input side. The x-ray C-arm apparatus features a user interface with a control element connected at least indirectly to the control facility, with the control element being effectively connected to the x-ray C-arm. 
         [0006]    The control element is connected to the user interface and embodied such that it can be moved with at least one rotational and with at least one translational degree of freedom. The user interface is embodied to detect the movement of the control element and to generate the control signal depending on the movement of the control element, with the control signal representing at least the degree of freedom and/or a direction of movement of the control element, especially a direction of movement in the degree of freedom. Such a user interface enables the x-ray C-arm to be conveniently controlled; in particular a degree of freedom of a movement of the C-arm can correspond to a prespecified degree of freedom of the movement of the control elements and/or the direction of movement. 
         [0007]    In a preferred embodiment the control element is connected to the user interface and embodied so as to enable movement with at least two rotational and/or at least two translational degrees of freedom. This advantageously allows an x-ray C-arm to be controlled in a convenient manner. 
         [0008]    For example the x-ray C-arm can be embodied to be moved in at least two rotational and/or at least two translational degrees of freedom depending on the control signal received on the input side. Preferably the control signal represents the at least two rotational and/or the at least two translational degrees of freedom. The rotational movement of the x-ray C-arm also preferably corresponds to the rotational movement of the control element and/or the translational movement of the x-ray C-arm corresponds to the translational movement of the control element, in particular the movement of the x-ray C-arm additionally corresponds to a direction of movement of the control element. This advantageously enables control of the x-ray C-arm to be intuitive. 
         [0009]    In a preferred embodiment the control element is especially connected to the user interface by means of at least one spring element and embodied to be moved, with three rotational and/or three translational degrees of freedom. This advantageously allows a complete coupling to be achieved between x-ray C-arm and the control element. 
         [0010]    The control element can for example be connected by means of at least one swivel bearing and/or slide bearing to the user interface, especially to a housing or frame of the user interface. The control element can for example be connected by means of at least one spring element to the user interface, especially to a housing or frame of the user interface. 
         [0011]    A swivel bearing, a slide bearing or a spring element allows the control element to be moved in one degree of freedom, especially to be limited to the degree of freedom. 
         [0012]    In an advantageous embodiment the control element is connected by means of at least one magnetic field to the user interface. To this end a housing or frame of the user interface and the control element can each feature a ferromagnet, with said magnets being arranged and polarized in relation to each other so that the control element is kept floating and can be moved against a force of the magnetic field. 
         [0013]    The control facility is also preferably embodied to move the x-ray C-arm in three rotational and/or three translational degrees of freedom. 
         [0014]    In an advantageous embodiment the control element can be moved in more degrees of freedom than the user interface can detect. The user interface is embodied in this embodiment to restrict, the number and/or type of the detectable degrees of freedom. This advantageously enables incorrect operations to be prevented. 
         [0015]    One rotational movement of the x-ray C-arm in this case also preferably corresponds to a rotational movement of the control element and/or a translational movement of the x-ray C-arm corresponds to a translational movement of the control element, especially such that a spatial arrangement of the axes of rotation of the control element to each other corresponds to a spatial arrangement of axes of rotation of the x-ray C-arm to each other, and/or a spatial arrangement of axes of translation of the control element to each other corresponds to a spatial arrangement of axes of translation of the x-ray C-arm to each other. 
         [0016]    For example the axes of rotation of the control element can form an orthogonal system and the axes of rotation of the x-ray C-arm can form a corresponding orthogonal system. For example the axes of translation of the control element can form an orthogonal system and the axes of translation of the x-ray C-arm can form a corresponding orthogonal system. 
         [0017]    In this way for example a rotational movement of the control element, especially a nodding movement around a transverse axis, can bring about a corresponding nodding movement of the x-ray C-arm around a transverse axis. A rolling movement of the control element around a longitudinal axis can bring about a rolling movement of the x-ray C-arm around a corresponding longitudinal axis. A yaw movement of the control element around a vertical axis can bring about a yaw movement of the x-ray C-arm around a corresponding vertical axis. The names of the axes and the names of the rotational movements are chosen to allow orientation and do not rigidly define a spatial orientation of the control element in relation to a direction of gravitational acceleration, the control element can however be arranged in this way in relation to the direction of gravitational acceleration. 
         [0018]    In an advantageous embodiment variant the user interface is embodied to detect the movement of the control element optically. For example the user interface can feature at least one luminescence diode and at least one photo diode, photo transistor or at least one photo resistor for this purpose. 
         [0019]    The control element in this embodiment can be effectively connected to at least one beam interruption element which is arranged and embodied to interrupt a beam path, formed from at least one luminescence diode and the at least one photo diode, depending on a movement of the control element. 
         [0020]    The user interface in this embodiment is embodied to detect the interruption of the beam path, especially a change in the current flowing through the at least one photo diode, and to generate the control signal depending on the interruption of the beam path, especially depending on the current flowing through the photo diode. 
         [0021]    In another embodiment the user interface has a housing or a frame, with the control element being effectively connected by means of at least one spring element to the frame or the housing respectively. 
         [0022]    The spring element is preferably embodied, depending on a compression and/or an expansion of the spring element, to alter an ohmic resistance of the spring element. The user interface is embodied in this embodiment to detect the alteration of the ohmic resistance of the at least one spring element and to generate the control signal depending on the alteration of the ohmic resistance. 
         [0023]    In another embodiment the user interface is embodied to detect the movement of the control element magnetically. For example in this form of embodiment the control element can be effectively connected to at least one ferromagnet and the user interface can in this embodiment feature at least one Hall sensor which is arranged and embodied so as to detect the movement of the at least one ferromagnet. The user interface in this embodiment is embodied to generate the control signal depending on the movement of the at least one ferromagnet. 
         [0024]    In a preferred embodiment the user interface features a safety element which is embodied to detect touching and/or movement, especially pushing or pulling of the safety element by a user, and to generate an enabling signal as a function of the touching and/or movement, and to output said signal on the output side. The user interface in this embodiment is preferably embodied to generate the control signal additionally depending on the enabling signal. 
         [0025]    In this way it can advantageously be ensured that the control element is moved by a user. In this way an unintentional movement of the x-ray C-arm can advantageously be prevented. Typical forms of embodiment for a safety element are a button or a touch-sensitive surface. The touch-sensitive surface can be embodied to conduct electricity and form a part of a capacitor. 
         [0026]    For example the user interface can be embodied to detect a connection of the touch-sensitive surface by a user to ground potential, especially to detect this capacitively. 
         [0027]    In another form of embodiment the user interface can be sensor with at least two transistors connected in a Darlington arrangement with an input of the Darlington arrangement being connected to the touch-sensitive surface. In this embodiment a user can act like a receiving antenna and direct energy from an electromagnetic field, for example caused by power lines, onto the touch-sensitive surface. 
         [0028]    In a preferred embodiment of the user interface a pressure point is embodied along at least one rotation path and/or along at least one translation path of the control element. A pressure point can for example be embodied such that a resistance to movement is increased along sections of a rotation and/or translation path and when or after the pressure point is overcome, a control signal corresponding to the degree of freedom can be generated by means of the control element. 
         [0029]    The safety element can advantageously be arranged in the area of the control element or on the control element. The safety element can preferably form an area or at least two areas of a control surface which is provided to allow touch control by the user. 
         [0030]    For example the enabling signal can be created depending on touching at least two independent touch-sensitive surfaces. This advantageously enables an accidental movement of the x-ray C-arm to be avoided. For example a control element can feature two touch-sensitive surfaces, which are arranged opposite each other such that a first touch-sensitive surface can be touched by a user&#39;s thumb and a second touch-sensitive surface by an index finger or by another finger. The control element can be embodied to be at least partly held within a user&#39;s hand. In this way a touching of the control element by a user can advantageously be detected. 
         [0031]    In an advantageous embodiment the C-arm x-ray apparatus is embodied to continue a movement of the x-ray C-arm depending on a location of the x-ray C-arm in at least one other degree of freedom. For example the C-arm x-ray apparatus can move the x-ray C-arm, especially by means of the control device to a predetermined location depending on the control signal. From the predetermined location onwards, the control apparatus can continue the x-ray C-arm in at least one other or precisely one other degree of freedom. 
         [0032]    For example the x-ray C-arm can be moved up to the predetermined location in a translation. From the predetermined location onwards the x-ray C-arm can be moved further in a rotation. 
         [0033]    The invention also relates to a method for moving an x-ray -C-arm of an x-ray C-arm apparatus by means of a control element effectively connected to the x-ray C-arm, with the x-ray C-arm moving depending on a translational movement and/or a rotational movement of the control element. 
         [0034]    In an embodiment variant of the method the x-ray C-arm is advantageously moved with at least one translational and/or with at least one rotational degree of freedom. 
         [0035]    In an embodiment variant of the method a rotational movement of the x-ray C-arm is undertaken depending on a rotational movement of the control element. 
         [0036]    In a preferred embodiment of the method a translational movement of the x-ray C-arm is undertaken depending on a translational movement of the control element. 
         [0037]    Advantageously in this case a movement of the x-ray C-arm can be undertaken according to a direction and/or a sense of direction of the movement of the control element. 
         [0038]    The previously described embodiment variants of the C-arm x-ray apparatus are based on the common idea of performing an intuitive and safe control of an x-ray C-arm by means of an improved control element. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0039]    The invention will now be described below with reference to Figures and further exemplary embodiments. 
           [0040]      FIG. 1  shows an exemplary embodiment for an x-ray C-arm apparatus with an x-ray C-arm and a user interface; 
           [0041]      FIG. 2  shows an exemplary embodiment for a control element of a user interface and possible directions of movement of the control element; 
           [0042]      FIG. 3  shows an exemplary embodiment for a user interface; 
           [0043]      FIG. 4  shows exemplary embodiments for directions of movement of the control element in translational and/or rotational degrees of movement. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0044]      FIG. 1  shows a schematic diagram of an exemplary embodiment for an x-ray C-arm apparatus  1 . The x-ray C-arm apparatus features an x-ray C-arm and a control facility. The control facility  5  is connected by means of a control mechanism  7  to the x-ray C-arm  3  and is embodied to move the x-ray C-arm  3  in at least one rotational and at least one translational degree of freedom by means of the control mechanism  7 . 
         [0045]    The C-arm x-ray apparatus  1  also features a user interface  9 . The user interface  9  features a movably embodied control element  10 . The user interface  9  also features a processing unit  12  which is embodied, depending on a sensor signal received on the input side and depending on an enabling signal received on the input side, to generate a control signal and output this on the output side. 
         [0046]    The user interface  9  also features an optical sensor  14 . The optical sensor  14  is embodied to detect a movement of the control element  10  by means of an optical beam  16  to generate a sensor signal corresponding to the detected movement and to output this on the output side. The optical sensor  14  is connected via a connecting line  20  to the processing unit  12 . The processing unit  12  is connected on the input side via a connecting line  18  to a touch sensor  15 , which is connected on the input side to a sensor surface  17  and to a sensor surface  19 . 
         [0047]    The touch sensor  15  is embodied to detect a simultaneous touching of the sensor surfaces  17  and  19  by a user and to create an enabling signal depending on the simultaneous touching and to output this on the output side via the connecting line  18  to the processing unit  12 . 
         [0048]    Also shown are a vertical axis  24 , a transverse axis  26  and a longitudinal axis  28 , which are each orthogonal to one another and together form an orthogonal system. The control element  10  is embodied,—for example guided by a user&#39;s hand  80 , to be moved along the longitudinal axis  28  and in doing so to execute a translation movement. 
         [0049]    The control element  10  is also embodied to be moved along a transverse axis  26  and in doing so to execute a translation movement. The control element  10  is also embodied to be moved along a vertical axis  24  and, in doing so, to execute a translation movement. The translation movements of the control element  10  can be guided in each case by a user&#39;s hand  80 . 
         [0050]    The control element  10  is also embodied to execute in a rotational degree of freedom  32  a nodding movement around the transverse axis  26 . The control element  10  is also embodied to execute a yaw movement in a rotational degree of freedom  30  around the vertical axis  24 . The control element  10  is also embodied to execute a rolling movement in a rotational degree of freedom  34  around the longitudinal axis  28 . The rotation movements of the control element  10  can each be guided by the hand of the user  80 . 
         [0051]    The optical sensor  14  is embodied to generate the beam  16  for detecting a movement of the control element  10  and to detect the movement of the control element  10  by means if the beam  16 . The optical sensor  14  can in such cases detect a translation movement along the transverse axis  26 , along the longitudinal axis  28  or along the vertical axis  24  or along a combination of these. The optical sensor  14  is embodied in such cases to detect a direction of movement along at least one of the axes  26 ,  28  or  24  and to generate a corresponding sensor signal. The names “vertical axis  24 ”, “transverse axis  26 ” and “longitudinal axis  28 ” are selected for orientation purposes and do not absolutely fix an orientation of the control element  10 , however the control element can be arranged in this way. 
         [0052]    The hand of the user  80  can for example move the control element  10  along the longitudinal axis  28  in a translational degree of freedom. When the hand of the user  80  touches the sensor surfaces  17  and  19  at the same time, the touch sensor  15  generates an enabling signal and sends this via the connecting line  18  to the central processing unit  12 . 
         [0053]    The optical sensor  14  can use the beam  16  to detect the translation movement along the longitudinal axis  28  and create a corresponding sensor signal and send this on the output side via the connecting line  20  to the processing unit  12 . The processing unit  12 , depending on the enabling signal and on the sensor signal, can generate a control signal to control the control unit  5  and output this signal on the output side. 
         [0054]    The processing unit  12  is connected to the control unit  5  on the output side via a connecting line  22 . The control unit  5  can, depending on the control signal received on the input side, use the control mechanism  7 , which can for example have at least one motor for moving the x-ray C-arm, to move the x-ray C-arm in accordance with the control signal in a translational degree of freedom. If the hand of the user  80  moves the control element  10  in a rotational degree of freedom  30 ,  32  or  34 , the control unit  5  can, in accordance with the previously described signal path, move the x-ray C-arm  3  using the control mechanism  7  in a degree of freedom corresponding to the rotational degree of freedom  34  or  30 . 
         [0055]      FIG. 2  shows a schematic diagram of an exemplary embodiment of an x-ray C-arm  36 . The x-ray C-arm  36  features an x-ray transmitter  42  and an x-ray receiver  44 . The x-ray transmitter  42  is arranged in the area of a first end of the x-ray C-arm  36  and the x-ray receiver  44  is arranged in the area of a second end of the x-ray C-arm  36  such that an object—for example a part of a human body—arranged in the area of an isocenter  40  can be irradiated by means of an x-ray beam emitted by means of the x-ray transmitter  42  along one direction of detection  38 . 
         [0056]    The x-ray receiver  44  is arranged and aligned so as to receive the x-ray beam emitted from the transmitter  42 . The x-ray C-arm  36  is embodied to execute a translation movement along a longitudinal axis Y, along a transverse axis X, or along a vertical axis Z, or along a combination of these axes of translation. 
         [0057]    The x-ray C-arm  36  is also embodied to execute a swivel movement along a rotational degree of freedom  46 , along of a rotational degree of freedom  48  or along a rotational degree of freedom  50 . A rotational movement of the x-ray C-arm  36  in the rotational degree of freedom  48  or in the rotational degree of freedom  46  is undertaken in this case around an axis of rotation, which runs through the isocenter  40 . 
         [0058]      FIG. 3  shows a schematic diagram of an exemplary embodiment for a user interface  52 . The user interface  52  features a housing  56  and a control element  54  linked to the housing. The control element  54  is for example connected in a sprung manner to the housing  56 , especially by means of at least one pair of opposingly polarized ferromagnets or by means of at least one spring element. 
         [0059]    The control element  54  is embodied to execute a translation movement along a transverse axis  26 , along a longitudinal axis  28  or along a vertical axis  24 . The control element  54  is also embodied to execute a nodding movement in a rotational degree of freedom  60  around the transverse axis  26 , a rolling movement in a rotational degree of freedom  64  around the longitudinal axis  28  or a yaw movement in a rotational degree of freedom  62  around the vertical axis  24 —for example each guided by a user&#39;s hand  80 —. 
         [0060]    The user interface  52  also features keys, of which the keys  58  and  59  are shown as typical examples. The user interface  52  can for example by embodied, depending on an enabling signal generated by pressing the key  58  and depending on a movement of the control element  54 , to generate a control signal for controlling the x-ray C-arm  36  shown in  FIG. 2  of for controlling the control facility  5  shown in  FIG. 1 . 
         [0061]      FIG. 4  shows a schematic exemplary embodiment for directions of movement of the control element  10  in translational and/or rotational degrees of freedom. If the control element  10  senses a translational movement  66  along the transverse axis  26 , the x-ray C-arm  36  shown in  FIG. 2  can execute a corresponding movement along the transverse axis X. If the control element  10  senses a translational movement  68  along the transverse axis  28 , the x-ray C-arm  36  shown in  FIG. 2  can execute a corresponding movement along the transverse axis Y. The control element  10  can also be moved along a vertical axis in direction  70 , especially pulled. This can for example bring about a movement of the x-ray C-arm along a vertical axis Z in a corresponding direction. 
         [0062]    The control element  10  can also be moved along a vertical axis in an opposite direction  71  to the direction  70 , especially pushed. This can for example bring about a movement of the x-ray C-arm along a Z-axis shown in FIG.  2 —in the opposite direction to the direction produced by moving the control element  10  in the direction  70 . 
         [0063]    In another embodiment a movement of the control element  10  along a vertical axis in direction  71  can cause an enabling signal to be created. 
         [0064]    The control element  10  can also be moved around the vertical axis  24  shown in  FIG. 1  in direction of rotation  72  or in a direction of rotation  73  opposite to the direction of rotation  72 . A movement of the control element  10  along the direction of rotation  72  or  73  can for example bring about a rotation of the x-ray C-arm  36  shown in  FIG. 2  around the Z-axis. In this case a direction of rotation of the rotation of the x-ray C-arm  36  can be a function of a rotation of the control element  10  in the direction of rotation  72 . A rotation of the control element  10  in the direction of rotation  73  can bring about an inverse rotation of the x-ray C-arm  36 . 
         [0065]    The control element  10  can also be rotated around a longitudinal axis  28  in a direction of rotation  76  or in an opposing direction of rotation  77 . The rotation of the control element  10  in the direction of rotation  76  can cause a rotation of the x-ray C-arm  36  in direction of rotation  48  around the Y axis. The rotation of the control element  10  in the direction of rotation  77  can bring about a rotating x-ray C-arm  36  in a direction of rotation which is opposite to the rotation of the x-ray C-arm  36  brought about by the rotation of the control element  10  in direction of rotation  76 . 
         [0066]    The control element  10  can also be rotated around the transverse axis  26  in a direction of rotation  74  or around the transverse axis  26  in a direction of rotation  75  opposite to the direction of rotation  74 . The rotation of the control element  10  in direction of rotation  74  can bring about a rotation of the x-ray C-arm  36  shown in  FIG. 2  around the X-axis shown in  FIG. 2 . A rotation of the control element  10  around the transverse axis  26  can also, depending on a local positioning of the x-ray C-arm  36 , bring about a rotation of the x-ray C-arm  36  around the Y-axis in the rotational degree of freedom  48 . That can for example occur if the x-ray C-arm  36  surrounds an end area of a patient bed coming from the front side of the patient bed, in which case a longitudinal direction of the patient bed can run in parallel to the X-axis.