Measurement system and procedure

Abstract

Measuring system for checking and / or calibrating a driving accuracy of a mobile medical device that can be moved automatically or semi-automatically by motor on the floor, in particular a mobile C-arm X-ray device (1), comprising a • Flat base (7) with a bottom side which can be arranged on the floor and with a top side (12) on which display structures are arranged which have at least one zero point marking (8) for positioning the medical device and a plurality of lane markings for driving movements of the mobile device, and a • Unit (10) for illuminating the display structures arranged on the base (7) using at least one bundled light beam, which unit (10) can be arranged, in particular detachably, on the mobile medical device in such a way that the light beam is directed onto the upper side (12) of the base (7).

Description

The invention relates to a measurement system for checking and / or calibrating a driving accuracy of a mobile medical device that can be moved by motor on the floor according to patent claim 1 and to a method for checking a driving accuracy of a mobile medical device that can be moved on the floor using such a measurement system according to patent claim 16.Regardless of the grammatical sex of a certain term, individuals with male, female or other sex identity are included.Mobile medical imaging devices, e.g. mobile C-arm X-ray devices, often have a C-arm with a recording system arranged thereon, which C-arm is arranged on a device carriage. The C-arm or its holder is provided with drives, for example, in order to adjust the angle of inclination, so that the recording system can be adjusted spatially in a plurality of projection directions. The apparatus truck is equipped with wheels on which the mobile X-ray apparatus can be moved manually. In addition, it is known to drive the wheels in a motorized manner in order, on the one hand, to enable the movement of the device carriage with less or completely no exertion of force and, on the other hand, to automate certain movements of the mobile X-ray device for clinical applications. Modern mobile X-ray devices are used in many fields, for example for intraoperative imaging in surgical interventions. In addition to simple projection images, they are also suitable and usable for 3D imaging or for panoramic imaging. In particular for such inserts, it is necessary to position the device carriage accurately and in particular repeatably accurately with respect to the patient to be treated before each insert.Mobile C-arm X-ray apparatuses with a motorized apparatus carriage have to be examined for their driving accuracy during production, before delivery or after certain service operations. For this purpose, it is evaluated how the actual trajectory behaves with respect to a predefined setpoint trajectory. For position travel, i.e. travel to a predetermined desired point, it is possible in particular to compare the difference between desired and actual positions. It is known, particularly in the case of a mecanum-based omnidirectional chassis, that deviations can occur in the two main directions x, y (for example according to the coordinate system of the mobile device, X: forward / rearward and Y: sideways) and in the case of chassis rotations φ (rotation about the chassis center).In order to measure the driving or movement accuracy, external tracking systems with cameras are used in the prior art. Alternatively, phantoms built up at the C-arm isocentre may be used.From the patent document DE 10 2017 007 511 B3 a device for maintaining the precision of the navigation capability of a automated guided vehicle is known, which device comprises a checking station with various markings for receiving the vehicle. From the post-published disclosure document DE 10 2022 107 804 A1, a positioning aid with templates for a motor vehicle test stand for testing driving assistance systems of automated motor vehicles is known.It is the object of the present invention to provide alternative measuring systems which make possible a simple and exact check of the driving accuracy; furthermore, it is the object of the invention to provide a method which carries out a check.The object is achieved according to the invention by a measurement system for checking and / or calibrating a driving accuracy of a mobile medical device which can be moved by motor on the floor according to patent claim 1 and by a method for checking a driving accuracy of a mobile medical device which can be moved on the floor using such a measurement system according to patent claim 16.The measuring system according to the invention has a flat base with an underside, which can be arranged on the floor, and with an upper side, on which display structures are arranged, which display structures have at least one zero point marking for positioning the medical device and a multiplicity of roadway markings for travel movements of the mobile device, and has a unit for illuminating the display structures arranged on the base using at least one bundled light beam, which unit can be arranged, in particular releasably, on the mobile medical device in such a way that the light beam is directed onto the upper side of the base.The flat base can be placed on the floor, so that a mobile device can be arranged thereon or next to it and, for example, can also be moved thereon. The display structures are arranged on the upper side of the base, for example as depressions or bulges or printed or embossed. The support is used for an initial alignment of the mobile device in order to establish defined starting conditions. The lighting unit is fastened to the mobile device, e.g. clamped, screwed, palleted or plugged. The light beam of the illumination unit is then directed onto the substrate and impinges thereon, so that it is visible, for example, in the form of an in particular visible light spot or light spot. The light beam can, for example, impinge orthogonally in order to generate particularly reproducible conditions. The flat base can be made, for example, from plastic or rubber, alternatively also from carbon, metal or natural fibers.The measuring system according to the invention enables the driving accuracy of the mobile device to be checked qualitatively and quantitatively in a simple manner, with little effort and very precisely even by an unskilled operator. This can be carried out, for example, by positioning and aligning the mobile device at the zero point marking (which represents, for example, a cross structure) and then carrying out movements along the roadway markings, which movements can be observed while following the area of incidence of the light beam on the flat base (i.e., for example, light point or light spot). This can be carried out manually by an operator (e.g. service technician) or (partially) automatically. The underlay can be quickly and easily packaged, transported and laid out on the floor. The fastening of the illumination unit to the mobile device is preferably releasable and can therefore likewise be arranged only for the purpose of checking and can subsequently be removed again. In addition, the measurement system can also be used to calibrate the driving accuracy by taking into account deviations from predefinable distances and travel paths. There is no need for a complicated check of the driving accuracy by means of external tracking systems, which are frequently expensive and space-consuming. By means of the measuring system according to the invention, a check can therefore also be carried out more frequently, because it can be done quickly in the meantime. This in turn leads to a higher resulting driving accuracy and thus to higher-quality imaging and better examinations.According to one embodiment of the invention, the roadway markings have at least three lanes, in particular two straight lanes arranged orthogonally to one another and one at least partially curved lane. By means of the two lanes standing orthogonally on one another, the two main directions of the coordinate system x and y (i.e. forwards / backwards and sideways with appropriate positioning with respect to the wheels of the vehicle) can be checked independently of one another at least at a distance in respect of the driving accuracy, while a curved, in particular circular-arc-shaped, lane is suitable for checking the driving accuracy with respect to rotations about a chassis center (φ). In addition, one or more further lanes can be arranged on the substrate, e.g. lanes arranged diagonally to the main directions and further rectilinear or curved lanes of different distances.According to a further embodiment of the invention, the lanes each have at least one starting marking and one destination marking. Thus, the driving accuracy is particularly easy and quick to recognize, for example when the mobile device is controlled for automatically covering the distance with a known distance between the start and the destination. In this case, for example, the light beam is first directed onto the start marking and, after the end of the travel movement, it is checked at which position the light beam is located. The respective target marking can also be used as a start marking and vice versa. If a plurality of lanes of different lengths are located one above the other (e.g. along the x-axis and y-axis), this can only be recognizable with the aid of a plurality of target markings, since the lanes are then at least partially the same.According to a further embodiment of the invention, the display structures contain coordinate system structures and / or grid structures and / or size data and / or defect area markings. Such structures clearly facilitate quantitative checking or analysis of the driving accuracy. Thus, for example, by means of error range markings (circles, squares, rectangles) around a target marking, it can be established at a glance whether or not the driving accuracy remains within a threshold value. Size data and grid structures such as, for example, scales (millimeter scale, degree scale, etc.) likewise significantly facilitate the reading of deviations from an operator. The display of a coordinate system can be used, for example, for simple and rapid positioning and orientation setting of the mobile device.According to a further embodiment of the invention, the base can be assembled in modular fashion from at least two base modules. Such a base can be transported and stored particularly easily. In particular, the base has a multiplicity of base modules which can be shaped and assembled in the manner of a puzzle. Such a puzzle requires particularly little space when it is not used and can be constructed quickly if required because of the one-to-one composition of a puzzle. The orientation and orientation of the display structures is likewise clearly predefined and fixed by the puzzle shape, so that nothing can slip.Advantageously, for clear visual recognizability, the display structures are formed from points and / or lines and / or circles and / or circle segments and / or rectangles. The display structures may be recognizable only by colors different from the base (e.g., colored or black / white) or may actually be bounded as a structural element from the rest of the base, or both.According to a further embodiment of the invention, the illumination unit is formed by a laser. A laser has a particularly long life and ensures the generation of a light spot or light spot that can be recognized particularly clearly optically in the region of the area of incidence on the substrate.According to a further embodiment of the invention, the measuring system is also assigned a control unit with a control program for automatically controlling predefined travel movements of the mobile device on the base. The control unit can be part of the mobile device onto which the control program is loaded and stored. In this case, the control program is designed to output control specifications for setpoint trajectories of the mobile device along the roadway markings of the substrate, in particular from the starting marking to the destination marking of the respective lane and / or back, each setpoint trajectory being assigned to a lane. Some of the setpoint trajectories are, for example, linear travel movements in the abovementioned main directions X, Y, which are each assigned to a corresponding linear lane(s). A lane may also be assigned multiple target trajectories (e.g., only forward and forward and backward). The length of the controlled desired trajectory corresponds, for example, to the distance between the starting marking and the destination marking of the associated lane. Some of the setpoint trajectories are, for example, curved travel movements about a radius (rotation about the road center / isocentre, Phi) which is assigned to a curved lane in each case. The length of the controlled setpoint trajectory can likewise preferably correspond to the distance between the starting marking and the destination marking of the associated lane. In addition, supplementary specifications of further desired trajectories, e.g. travel movements along diagonal lanes, desired trajectories of different lengths, etc., can also be provided; these are also always assigned to the corresponding lanes of the flat support. For example, the control specifications consist of pairs of setpoint trajectories, wherein the second setpoint trajectory inverts the first setpoint trajectory in order to measure both precision and repeatability.According to a further embodiment of the invention, the measuring system comprises a detection unit for detecting an actual position of the mobile device relative to the display structures. If, in addition or as an alternative to a manual check of the driving accuracy by an operator using the measurement system, an automatic check is to be carried out, the detection unit can record, for example, the light beam / light spot / light spot of the illumination unit or its movement relative to the display structures. For this purpose, the detection unit can be, for example, a camera which is arranged, for example, together with the illumination unit on a holder, which holder can then be detachably fastened to the mobile device. In order to be able to perform a particularly precise and rapid automatic check, the measuring system according to a further embodiment of the invention has an evaluation unit for evaluating the position of the mobile device detected by the detection unit relative to the display structures with regard to a deviation of an actual position from a setpoint position and / or with regard to a deviation of an actual trajectory from a setpoint trajectory. As a result, automatic analysis of the driving accuracy is quickly available and can be fed back to the operator or otherwise used further if necessary.According to a further embodiment of the invention, an alignment unit arranged on the mobile device, in particular a unit for producing a laser cross, is used for aligning the mobile device with the flat base. Mobile X-ray apparatuses generally have a unit for generating laser lines or a laser cross in order to visualize the isocentre. This alignment unit can likewise be used without effort to positionally align, i.e. position, the mobile device and adjust the orientation. This can be done, for example, with respect to the zero point marking or other display structure of the flat substrate. It is important here that the coordinate systems of the mobile device and of the flat base are aligned in a defined manner with respect to one another (in particular congruently).According to a further embodiment of the invention, the base has at least one cutout. In particular, the base has at least two recesses which are arranged at defined distances and are designed for inserting test elements for checking distance sensors arranged on the mobile device. Mobile devices, for example automatically movable mobile X-ray devices, frequently have a collision sensor system. For example, a mobile X-ray device with a lidar sensor, which is arranged in such a way that it scans at least a part of the environment of the device cart and a device section, is known from the publication document DE 10 2021 210 771 A1. In order to calibrate such a collision sensor system, for example, two cuboids of fixed shape and size can be used, which are arranged in a precisely fixed position and distance. The recesses arranged in the base allow the cuboids to be arranged very easily in exactly the correct position and orientation and thus a rapid and simple calibration to be carried out.The invention also comprises a method for automatically checking the driving accuracy of a mobile medical device that can be moved on the floor using the described measurement system, having the following steps: establishing a reproducible alignment of a coordinate system of the support with respect to a coordinate system of the mobile medical device by arranging the mobile medical device on the support in a predefined position and orientation, in particular with respect to the zero point marking, positioning the light beam emanating from the illumination unit in such a way that said light beam illuminates a starting or target marking and controlling at least one target trajectory by the control unit with the control program for moving the mobile device along the lane assigned to the target trajectory. An automation of the further method comprises the following steps: detecting the actual positions of the medical device relative to the display structure at least at the end of the setpoint trajectory, in particular also during the setpoint trajectory, evaluating the detected actual positions, in particular with regard to a deviation from a predefined setpoint position, wherein the deviation represents a measure for the driving accuracy of the device, and outputting an indication or a display on the basis of the evaluation.According to a further embodiment of the invention, when a threshold value for a deviation is exceeded, recalibration of the control unit with the control program is instructed and / or carried out. Correction values can also be determined for these by quantitatively determining and taking into account the deviations.The invention and further advantageous embodiments according to features of the dependent claims are explained in more detail below with reference to schematically represented exemplary embodiments in the drawing, without the invention thereby being limited to these exemplary embodiments. The following are shown: FIG. 1 is a view of a medical C-arm mobile X-ray device; FIG. 2 shows an oblique top view of the top side of a base as part of a measurement system for checking the driving accuracy of a mobile device; FIG. 3 shows a view of an illumination unit as part of a measurement system for checking the driving accuracy of a mobile device; FIG. 4 is an oblique top view of the top side of a modular base; FIG. 5 shows a further oblique top view of the top side of a modular base with test elements inserted into the recesses; FIG. 6 shows a sequence of steps of a method for checking a driving accuracy of a mobile medical device that can be moved on the floor; and FIG. 7 is a side view of a substrate and a C-arm mobile X-ray apparatus partially disposed on the substrate; FIG. 8 shows a view of a mobile C-arm X-ray apparatus with an illumination unit arranged thereon; and FIG. 9 shows a further sequence of steps of a method for checking a driving accuracy of a mobile medical device that can be moved on the floor.FIG. 1 shows a known mobile medical C-arm x-ray device 1 which can be moved by means of motorized omnidirectional wheels 6. The mobile medical C-arm X-ray device 1 has a C-arm 2, on which an X-ray source 4 and an X-ray detector 3 are arranged. The C-arm 2 is in turn arranged on a tool carriage 5, which in turn comprises the wheels 6. The C-arm X-ray device 1 is controlled by a control unit 14, for example with regard to travel movements of the motorized wheels 6 on the floor. The travel movements can be controlled as desired, e.g. forwards / backwards, sideways (with respect to the alignment of the wheels 6), in curves etc. In order to check the travel accuracy of such a mobile C-arm X-ray device 1 and generally each mobile medical device that can be moved in a motorized manner quickly and with little effort and to calibrate it if necessary, the measuring system according to the invention is provided, which comprises at least one support 7 (FIGS. 2, 4 and 5 ) and an illumination unit 10 (FIG. 3 ).In FIG. 2 a simple flat base 7 is shown with a bottom side (not visible) that can be arranged on the floor and a top side 12 with display structures. The flat base 7 has a small height and is formed in such a manner that a mobile device can easily travel on it without producing a tilting of the device even if only a part of the, for example, four wheels are located on the base. The display structures comprise a zero point marking 8, which serves as a starting point for positioning the mobile device. The zero point marking 8 can be formed accordingly, for example, from the zero point of a coordinate system having an x-axis x and a y-axis y. In this way, the zero point marking 8 is formed, for example, as a cross, which is particularly suitable for positioning by means of a laser cross, as is present on a typical C-arm X-ray device 1 for visualizing the isocentre. The zero point marking 8 can also be designed as a starting marking 23 and / or can be the center point of a surrounding circle, square or rectangle, which can represent an error region 20 for the positioning.The display structures of the base 7 also comprise a plurality of roadway markings for travel movements of the mobile device. In this case, for example, at least two straight lanes 9.1 and one curved lane 9.2 are included. The two straight lanes 9.1 are arranged orthogonally to one another; in the example shown, they are formed (at least partially) by the x-axis x and the y-axis y of the coordinate system. In this way, the zero point marking 8 forms the starting point 23 of the straight lanes 9.1. The straight lanes 9.1 have a predefined length, for example, and the target point 24 of the straight lane 9.1 is in turn surrounded by a circle or rectangle, which / s visualizes the error region 20. It is also possible for two or more target points 24 to be present at different distances from the start marking 23, if, for example, a plurality of straight lanes 9.1 of different lengths (distance between the start marking 23 and the target marking 24) are arranged one above the other.In addition to the straight lanes 9.1, which are arranged along the x-axis x or y-axis y of the coordinate system, there may also be further straight lanes present, e.g. in the diagonal of the coordinate system as depicted. In addition, the support 7 also comprises at least one curved lane 9.2, which likewise has its starting point 23 in the zero point marking 8 and comprises, for example, a partial circular arc. The curved lane 9.2 also has a target point 24, which can likewise have an error range. Here too, a plurality of target markings 24 can be present, that is to say a plurality of curved lanes 9.2 of different lengths (distance between start marking 23 and target marking 24). Different curved lanes 9.2 of different length and with a different radius may also be present. Preferably, but not necessarily, all lanes have their starting point 23 on the zero point marking 8.Size data and grid structures such as, for example, scales (millimeter scale, degree scale, etc.) can additionally be present on the base 7 and likewise significantly facilitate an operator reading deviations when viewing the incident surface of the light beam. The display of a coordinate system can be used, for example, for simple and rapid positioning and orientation setting of the mobile device.The display structures may be formed in different colors for better clarity. They can be formed as continuous lines, dots or dash dots. They can be painted, printed, embossed, etched, scored or applied by means of another known method, but they can also be produced as early as during the production of the base 7. The color of the display structures can also be designed to be light-intensifying in order to increase the visibility of the light spot.The flat support 7 shown in FIG. 2 is formed in one piece, while modular flat supports 7 comprising a plurality of support modules 7.1 are shown in FIGS. 4 and 5. The base modules 7.1 are designed in puzzle piece form and can be designed such that there is only a single possibility of assembling them. In this way, one-to-one composition of the modular base 7 is guaranteed. The display structures can extend over more than one substrate module 7.1, for example the linear lane 9.1, which lies on the x-axis x, extends over two sub-substrates 7.1, and the linear lane 9.1, which lies on the y-axis, extends over three sub-substrates 7.1. The substrate modules 7.1 can be easily plugged together if necessary and disassembled again and packaged. In the example shown, the base 7 has a total of six base modules 7.1, but can also be expanded if necessary.The substrate 7 also has two recesses 30, into which test elements 31 can be inserted if necessary. The test elements 31 are arranged at defined intervals by the recesses 30 into which they can be inserted directly and must have a defined size and shape in order to fit into the recesses 30. The test elements 31 can be used, for example, for checking distance sensors arranged on the mobile device. For example, a mobile C-arm X-ray device with a lidar sensor, which is arranged in such a way that it scans at least a part of the surroundings of the device cart and a device section, is known from the publication document DE 10 2021 210 771 A1. In order to calibrate such a collision sensor system, two such test elements 31 can be used, for example. The position of a lidar 32 (arranged on the C-arm X-ray device 1) in such a calibration is shown, see also FIG. 7.In FIG. 3 an illumination unit 10 is shown which comprises a laser 26 (in the figure the corresponding beam is directed downwards). The laser 26 can be adjusted by means of adjusting screws 27. The illumination unit 10 can be arranged on the mobile device by means of its clamping elements 25, for example on the C-arm of the C-arm X-ray device 1 (see FIG. 8 ). FIG. 7 shows a lateral view of only the laser beam 33 emitted by the laser 26 onto the flat substrate 7. For a particularly simple and stable adjustment, the laser beam 33 impinges orthogonally on the flat base 7. In FIG. 8, a possible positioning of the illumination unit 10 on the C-arm 2 is shown, the control unit 14 is located, for example, on the tool carriage 5.In order to carry out the method using the measurement system, a few preliminary steps by a service technician or another operator are first necessary. Thus, first the flat base 7 must be built up, e.g. by joining the base modules 7.1, and placed on the floor. In addition, the illumination unit 10 is fastened, e.g. clamped or screwed, to the C-arm 2 of the C-arm X-ray apparatus 1.The steps of the method are shown in FIG. 6. In a first step 50, the C-arm X-ray device 1 is reproducibly oriented on the base with respect to position and orientation in such a way that the respective coordinate systems of the mobile C-arm X-ray device 1 and of the flat base 7 are congruent. This can be done, for example, using the reticle 34 of the C-arm X-ray apparatus which is generally used to adjust the isocenter. Generally, a unit for producing such a laser cross 23 is provided on a C-arm X-ray apparatus 1. The alignment can be performed, for example, such that positioning on the origin mark 8 is performed by the reticle 34, and the orientation is adjusted by aligning the reticle 34 on the x-axis and y-axis.In a second step 51, the laser beam 33 of the laser 26 of the illumination unit 10 is adjusted, for example by means of the adjusting screws 27, in such a way that it is exactly directed onto the zero point marking 8 of the flat base 7, that is to say, for example, in such a way that the point of incidence is on the zero point marking and the light spot thus generated illuminates the zero point marking 8.Subsequently, in a third step 52, the monitoring of the driving accuracy is carried out by driving the mobile C-arm X-ray device 1 along the lanes 9.1; 9.2.For this purpose, for example, a dedicated and stored control program, which is controlled by a control unit of the mobile C-arm X-ray device 1, for example, is used. The control program contains control specifications for desired trajectories of the mobile C-arm X-ray device 1 along the lanes 9.1; 9.2 of the flat base 7 from the respective start marking 23 to the respective target marking 24 (only back and forth) in exactly the length which corresponds to the distance between the start marking and the target marking 24. Thus, for example, a setpoint trajectory of 50 cm in the x direction when the length of the straight lane 9.1 along the x axis is 50 cm (distance between start marking 23 and target marking), or 80 cm in the y direction when the length of the straight lane 9.1 along the y axis is 80 cm (distance between start marking 23 and target marking 24) can be controlled, and additionally the back directions can be controlled. The control program and the lanes of the flat support 7 are matched to one another accordingly; for each or at least for each important lane, a setpoint trajectory is contained in the control program. The control program thus contains at least target specifications for target trajectories for two mutually orthogonal straight lanes in the main directions (i, general x-axis x and y-axis y, which correspond generally forwards / backwards and sideways of the mobile device) and for the curved roadway in a circular path (φ). For example, coordinated with the flat support, further desired trajectories, for example diagonal travels, travels of different lengths in the same direction, circular trajectories of different radii, etc., can be provided as controllable desired trajectories. The setpoint specifications can have individual routes and / or pairs of journeys in each case, wherein the first is reversed (back and forth) during the second journey in order to measure the repeatability in addition to the precision.Within the scope of the verification of the driving accuracy, in the third step 52, the respectively associated setpoint trajectory along the two (or more) straight lanes 9.1 is now actuated successively, for example, starting at the start marking with the destination to arrive at the destination marking, possibly also at a setpoint trajectory which leads back and forth with the destination to arrive again at the start marking. The operator can observe, for example, by viewing how the light spot of the light beam / laser beam moves with respect to the driving lane. After completion of the respective desired trajectory, the operator then checks where the light spot is located, in particular whether it is located inside or outside the error region 20 of the target marking (or starting marking). If the light spot of the light beam / laser beam impinges outside the error range 20, the driving accuracy is not sufficient. Here, for example using grid structures or length information of the flat base 7, an exact deviation can then also be determined and measured manually by the operator. This can be performed for the pass and return path.The associated desired trajectory along the curved lane 9.2 is likewise also controlled, starting from the start marking. Here too, the operator can monitor the course, for example. After completion of the desired trajectory, the operator also examines whether the laser beam is within the error range 20 and, if necessary, how great the deviation is, not only with respect to the direction, but also with respect to the radius of the trajectory. This can be carried out simply and precisely by the measuring system comprising flat base 7, illumination unit 10 and possibly control program. Measured deviations can be used for recalibration if the deviations exceed the tolerance range. The manual measurement of deviations by the operator can be carried out, for example, using measurement tools such as inchstocks, etc.In addition to the three steps (see FIG. 6 ), further steps are shown in FIG. 9, wherein here, instead of the manual checking by an operator, further steps are carried out automatically.In a fourth step 53, the respective actual position of the medical device relative to the display structure (i.e. the lanes etc.) is detected during or after the travel movement of the mobile device using a detection unit arranged, for example, on the illumination unit. This can be carried out once at the end or after completion of the desired trajectory or continuously during the travel movement. The detection unit can be formed by a camera, for example. This records the exact position(s) of the light spot of the light beam / laser beam relative to the roadway markings or lanes, e.g. during the travel movement or at the end thereof. In the simplest case, only the actual position is detected at the end of the travel movement relative to the target marking.In a fifth step 54, the actual positions detected by the detection unit are evaluated, e.g. by an evaluation unit. The evaluation takes place in particular with regard to a deviation of the respective actual position from a predefined desired position. The actual position is formed, for example, by the detected position of the light spot of the light beam / laser beam, and the desired position is formed, for example, by the target (start) marking or the lane. From this, the exact deviation is determined. The deviation then represents a measure of the driving accuracy of the mobile device. It is also possible to carry out merely an evaluation as to whether the light spot is arranged inside or outside the target (start) marking or else an exact evaluation of the deviation takes place.In a sixth step 55, an indication or a display is output on the basis of the evaluation result. This can be carried out, for example, optically on a monitor, by a light display or a microphone. If no or only a slight deviation is below a threshold value (within the error range), an acknowledgment tone, an affirmative (e.g. green) light or an affirmative text indication can take place, for example. If the deviation is above a threshold value (outside the error range), a warning tone, a (e.g. red) warning light or a warning text can be output, for example.In a further step, when the threshold value for the deviation is exceeded, recalibration of the control unit with the control program can be instructed and / or carried out. Furthermore, the measured or determined deviations can be used for a calibration.The measurement system and the method can be used to measure the driving accuracy without radiation or external measurement systems (cameras). The use of a flat support enables a simple mechanical construction which can be divided modular into parts which can also be easily handled in the case of service. The size of the sub-bases can be chosen to fit into typical luggage / boxes used in service. The modularization also makes it possible to expand the flat support if future functions (e.g. panoramic imaging) require extended driving programs with greater distances. In conjunction with the control program assigned to the base and the illumination unit, which is stored or called up on the control unit of the mobile device, the verification and / or calibration can be carried out by a person without being trained into a more complicated measurement equipment.The support can also have light sensors, by means of which the movement of the light beam is directly detected. The recorded measured values can then be evaluated accordingly.The invention can be summarized briefly in the following manner: For a particularly precise check of the driving accuracy, a measurement system is provided for checking and / or calibrating a driving accuracy of a mobile medical device which can be moved automatically or semi-automatically in a motorized manner on the floor, in particular of a mobile C-arm X-ray device, having a flat base with an underside which can be arranged on the floor and with an upper side on which display structures are arranged which have at least one zero point marking for positioning the medical device and a multiplicity of roadway markings for driving movements of the mobile device, and a unit for illuminating the display structures arranged on the base using at least one bundled light beam, which unit can be arranged, in particular releasably, on the mobile medical device in such a way that the light beam is directed onto the upper side of the base.

Claims

Measuring system for checking and / or calibrating a driving accuracy of a mobile medical device which can be moved automatically or semi-automatically in a motorized manner on the floor, in particular of a mobile C-arm X-ray device (1), having a • flat base (7) with an underside which can be arranged on the floor, and with an upper side (12) on which display structures are arranged which have at least one zero point marking (8) for positioning the medical device and a multiplicity of road markings for driving movements of the mobile device, and a • unit (10) for illuminating the display structures arranged on the base (7) using at least one bundled light beam, which unit (10) can be arranged, in particular releasably, on the mobile medical device in such a way that the light beam is directed onto the upper side (12) of the base (7).Measuring system according to claim 1, wherein the roadway markings have at least three lanes, two straight lanes (9.1) arranged orthogonally to one another and one at least partially curved lane (9.2).Measuring system according to Claim 1 or 2, wherein the lanes (9.1; 9.2) each have at least one starting marking (23) and one destination marking (24).Measuring system according to one of the preceding claims, wherein the display structures contain coordinate system structures and / or grid structures and / or size specifications and / or defect area markings.Measuring system according to one of the preceding claims, wherein the base (7) can be assembled in modular fashion from at least two base modules (7.1).Measuring system according to claim 5, wherein the base (7) has a plurality of base modules (7.1), which are shaped and assembled in the manner of a puzzle.Measuring system according to one of the preceding claims, wherein the display structures are formed from points and / or lines and / or circles and / or circle segments and / or rectangles.Measuring system according to one of the preceding claims, wherein the illumination unit (10) is formed by a laser (26).Measuring system according to one of the preceding claims, to which a control unit (14) with a control program for controlling travel movements of the mobile device on the base (7) is additionally assigned.Measuring system according to claim 9, wherein the control program is designed to output control specifications for desired trajectories of the mobile device along the roadway markings of the base (7), in particular from the starting marking (23) to the target marking (24) of the respective lane (9.1; 9.2) and / or back, wherein each desired trajectory is assigned to a lane (9.1; 9.2).Measuring system according to one of the preceding claims, having a detection unit for detecting an actual position of the mobile device relative to the display structures.Measuring system according to claim 11, comprising an evaluation unit for evaluating the detected position of the mobile device relative to the display structures with respect to a deviation of an actual position from a desired position and / or with respect to a deviation of an actual trajectory from a desired trajectory.Measuring system according to one of the preceding claims, in which an alignment unit arranged on the mobile device, in particular a unit for producing a laser cross (34), is used for aligning the mobile device with the flat base (7).Measuring system according to one of the preceding claims, wherein the base (7) has at least one cutout (30).Measuring system according to claim 14, wherein the base (7) has at least two recesses (30), which are arranged at defined distances and are designed for inserting test elements (31) for checking distance sensors arranged on the mobile device.Method for checking the driving accuracy of a mobile medical device that can be moved on the floor using a measurement system (7; 10) according to one of Claims 1 to 15 and 10, having the following steps: • establishing a reproducible alignment of a coordinate system of the support (7) with respect to a coordinate system of the mobile medical device by arranging the mobile medical device on the support (7) in a predefined position and orientation, in particular with respect to the zero point marking (8), • positioning the light beam emanating from the illumination unit (10) in such a way that said light beam illuminates a starting and / or target marking (23; 24), • controlling at least one setpoint trajectory by the control unit (14) with the control program for moving the mobile device along the lane (9.1; 9.2) assigned to the setpoint trajectory.Method according to claim 16, additionally comprising the following steps: • detecting the actual positions of the medical device relative to the display structure at least at the end of the setpoint trajectory, in particular also during the setpoint trajectory, • evaluating the detected actual positions, in particular with respect to a deviation from a predefined setpoint position, wherein the deviation represents a measure for the driving accuracy of the device, and • outputting an indication or a display on the basis of the evaluation.Method according to Claim 17, wherein, if a threshold value for the deviation is exceeded, recalibration of the control unit with the control program is instructed and / or carried out.

Images