Control unit for mobile medical devices and mobile medical device

Abstract

The invention relates to a control device (9) for a mobile medical device (1), wherein the control device (9) comprises a controller (13) and a selection unit (12), wherein the controller (13) is configured to control and / or regulate a drive unit (5) of the mobile medical device (1), wherein the mobile medical device (1) comprises an operating device (3) for actuation by a user (2), wherein actuation data (7) from the operating device (3) are provided to the control device (9), characterized in that the controller (13) has at least two different controller settings, wherein the selection unit (12) is configured to select, set and / or use the controller setting based on the actuation data (7).

Description

[0001] In the medical field, particularly in hospitals and care facilities, mobile medical devices such as hospital beds, patient couches, imaging equipment, and treatment devices are becoming increasingly common. These devices are often heavy, weighing 100 kg or more. To facilitate handling, mobile medical devices frequently feature a drive mechanism, such as a motor, for assistance and / or autonomous and / or automated movement.

[0002] In self-propelled vehicles, a PI controller is used to regulate the position or speed of the various axles to the specified setpoint. A PI controller consists of a proportional part and an integral part. The proportional part (described by the control parameter K) pThe integral component reacts to the current error, that is, the deviation of the current actual value from the desired setpoint. However, the disadvantage is that the closer the setpoint and feedback get, the smaller the correction becomes. In theory, the setpoint is never reached. The integral component accumulates the errors over time and allows for finer adjustment of the control. The integral component can solve the problem of the proportional component failing to reach the setpoint. The integral component (described by the control parameter K) i The correction signal integrates the difference between the setpoint and the feedback. Even with small differences, after some time the correction signal becomes large enough to correct the error between the setpoint and the feedback.

[0003] High safety standards must be maintained in the context of using such mobile medical devices to ensure the safety and health of operators and / or patients, as well as property. Operators often describe handling such heavy mobile devices as unfamiliar. In particular, the device's response to control inputs and its overall behavior are often noticeable to them. Therefore, mobile medical devices with a drive unit frequently employ a controller that forms a control loop with the input unit and the drive unit.

[0004] Self-propelled vehicles can be controlled autonomously (the vehicle moves purposefully and independently without human intervention), automatically (predefined sequences are carried out independently by the vehicle or software according to specific specifications), or manually. In manual operation, the user controls the vehicle's trajectory using controls such as a steering wheel, force sensor, or joystick, thus becoming part of the control loop. Practical experience shows that controlling the vehicle is perceived as more pleasant when the directional input from the control system is transmitted to the actuators without delay.

[0005] In its simplest form, a vehicle with a differential drive consists of two driven wheels on one axle with one or at least two passive, free-rotating support wheels. The two driven wheels are located on the same axle and are controlled and driven independently. The vehicle is steered without steered wheels. To negotiate a curve, the drive wheels are steered at different speeds. The delay between the direction command and the realization of the desired trajectory is therefore directly linked to the time it takes to achieve the desired target speeds.

[0006] The PI controller is particularly suitable for precise autonomous / automatic vehicle operation. The PI controller with a small integral component, or the pure proportional controller, is perceived as particularly pleasant during manual vehicle control because the output signal to the vehicle's actuators is directly proportional to the new setpoint. The user already attempts to correct the constant control deviation of the proportional controller, and the time-integrated difference between the setpoint and feedback counteracts this with a delay. Therefore, the integral component is perceived by the user as disruptive and "stubborn" during manual operation.

[0007] Differential drives that frequently need to switch between autonomous / automatic and manual operation use a PL controller with control parameters K. p and K i , which result from a compromise for both operating modes.

[0008] Regardless of the grammatical gender of a particular term, persons with male, female or other gender identities are included.

[0009] The present invention relates to a control unit for a mobile medical device. The control unit can be designed as hardware, for example as an electronic module, or as software. The control unit is designed, in particular, to control and / or regulate a drive, especially the speed, acceleration, and / or direction of movement of the mobile medical device. The mobile medical device can be a hospital bed, a patient couch, a mobile head scanner, a mobile imaging device, or a mobile treatment unit. The mobile medical device has, in particular, a mass of at least 100 kg, and specifically, at least 500 kg.

[0010] A mobile medical device is, in particular, a movable medical device, especially one that can be moved manually, automatically, and / or autonomously. A mobile medical device specifically includes a drive unit.

[0011] The control unit is connected to the drive unit, specifically to a controller within the control unit, via a data connection, either wired or wirelessly. The control unit can be configured to control and / or regulate multiple wheels simultaneously and / or identically via the drive unit. Alternatively, the control unit can be configured to control and / or regulate wheels and / or axles separately and / or differently.

[0012] The control device comprises at least one controller. The controller can be implemented as software or as a hardware module. The controller is, in particular, part of a control loop. The control loop includes, for example, the drive unit and an operating device of the mobile medical device. The controller is specifically configured to regulate and / or control a controlled variable, wherein the controlled variable is, for example, a velocity, a wheel's rotational speed, an acceleration, a force, a steering angle, and / or another drive variable. The controller is preferably configured as a continuous controller. The controller includes and / or can be described by parameters, in particular a parameter set. The parameter set can, for example, include a proportionality factor and an integration constant to describe a proportional (PL) controller.

[0013] The control unit includes a selection unit. The selection unit can be implemented using software or hardware. The selection unit is preferably connected via data to an operating device of the mobile medical device and / or the controller. Specifically, the selection unit is configured to select and / or decide between options based on an input variable. Specifically, the selection unit is configured to select and / or set a behavior and / or a setting of the controller based on actuation data provided by the operating device.

[0014] Self-propelled mobile medical devices can be controlled autonomously (the vehicle moves purposefully and independently without human intervention), automatically (predefined sequences are carried out independently by the vehicle or software according to specific specifications), or manually. In manual operation, the user controls the vehicle's trajectory via controls such as a steering wheel, force sensor, or joystick, thus becoming part of the control loop.

[0015] The drive unit can, in particular, comprise one or more motors, for example, to drive and / or control an axle and / or wheels of the mobile medical device. The drive unit can specifically be part of a chassis and / or chassis of the medical device. The drive unit is preferably connected to the controller via data transmission.

[0016] The mobile medical device includes an operating device. The operating device may include, for example, an input device, a switch, a contact sensor, a force sensor, a joystick, or a button. The operating device is designed for operation and / or actuation by a user. The user can use the operating device to signal to the control unit, via actuation data, that they are in contact with the mobile medical device and / or wish to take active control. For example, the operating device may include and / or constitute a dead man's switch designed to signal the presence of an active user via actuation data. In other words, the actuation data may include information about whether a user is using, controlling, and / or regulating the mobile medical device, or whether no user is present.

[0017] A proportional (PL) controller is particularly suitable for the precise autonomous / automatic operation of mobile medical devices. A PL controller with a small integral (I) component, or a pure proportional (P) controller, is perceived as especially pleasant during manual control of the mobile medical device because the output signal to the vehicle's actuators is directly proportional to the new setpoint. The user already attempts to correct the constant control deviation of the proportional controller, and the time-integrated difference between the setpoint and feedback counteracts this with a delay. Therefore, the integral component is perceived by the user as disruptive and "stubborn" during manual operation.

[0018] The control unit, in particular the selection unit, is provided with the operating data. This operating data informs the control unit, and in particular the selection unit, whether a user is present and / or has taken control, or whether no user is present. For example, the operating data can include the position and movement of the control lever, indicating whether a user has taken control.

[0019] The controller comprises at least two controller settings. These two settings are distinct from one another, particularly in terms of controller behavior and / or parameters. For example, one controller setting could be a PL controller with fast response times, while another setting represents a PL controller with slow response times. The controller can operate in these two different settings. Switching between the different settings is also possible. For instance, one setting might describe a PL controller with a first set of parameters, and another setting might describe a PL controller with a different set of parameters.

[0020] The selection unit is trained to choose one of at least two controller settings based on the actuation data and / or to set or use the selected controller setting for the controller's operation. This means that the selection unit reacts to changes in the actuation data in real time and selects the optimal controller settings. In other words, the selection unit is trained to switch between controller settings based on the actuation data. For example, the selection unit is trained to select and / or switch between controller behavior and / or settings based on whether a user is present and / or actively wants to control the system. Thus, for example, upon detecting an active user, the selection unit could choose a controller setting with a lower integration factor, allowing for more direct control.

[0021] The invention is based on the idea of ​​switching between different controller settings and / or behaviors by evaluating the actuation data, instead of using a controller with a single behavior and / or setting that represents a compromise between several possibilities. This allows for the application of optimal controller settings and / or behaviors based on the actuation data, such as the presence or absence of a user. For example, it is possible to use a user-friendly controller setting and / or behavior when a user takes over control, such as a setting with a low integration factor, and to select a controller setting that does not need to consider user preferences when a user is not present, for example, in an automatic and / or autonomous control system.

[0022] Additionally, the selection unit can take into account whether the user is in a stressful situation. For example, additional sensors to monitor the user's condition, such as heart rate sensors or eye movement trackers, could be used to further optimize the controller settings.

[0023] In general, the control unit according to the invention reacts flexibly to different situations and user states in order to always provide the optimal controller settings. This leads to an improved user experience and more efficient control of the system.

[0024] It is particularly preferred that the at least two controller settings comprise a first controller setting and a second controller setting. The first controller setting comprises a first controller behavior, while the second controller setting comprises a second controller behavior. The controller behavior can be described, for example, by different parameters and / or parameter sets. For instance, the controller behavior can describe whether it is a proportional (P) controller, a pi (PI) controller, or a PID controller. Furthermore, the controller behavior can describe the proportions of different quantities, such as the proportional component and / or the integral component. The proportional component, in particular the control parameter K, p , and the integration component, in particular the control parameter K iThe parameters are preferably part of a parameter set for describing the controller's behavior. The selection unit is configured to select a controller behavior based on the actuation data, and in particular to switch between different controller behaviors. This means that the selection unit can react to changes in the actuation data in real time to apply the appropriate controller behavior. Specifically, the selection unit is configured to select, based on the actuation data, whether the first controller setting with a first controller behavior is applied and / or used by the controller, or whether the second controller setting with a second controller behavior is applied and / or used by the controller.

[0025] It is particularly preferred that the initial controller behavior of the first controller setting describes and / or corresponds to the behavior of a PI controller. In particular, the initial controller behavior includes an integration term and / or a control factor K. i non-zero. Specifically, the first controller behavior can also correspond to a PID controller. The selection unit is preferably configured to select the first controller behavior and / or a controller behavior of a PL controller for actuation data that includes the presence of an active user and / or information that the user wants to control and / or regulate the mobile medical device.

[0026] Furthermore, it is preferably provided that the second controller behavior of the second controller setting corresponds to a controller setting of a P-controller or a PL-controller with an integration term that is smaller than the integration term of the first controller behavior. In other words, the integration term and / or control factor K i The second controller setting is smaller than the first controller behavior.

[0027] Another item is a mobile medical device, for example, a mobile patient stretcher, a mobile patient bed, a mobile imaging unit, and / or a mobile treatment unit. The mobile medical device is, in particular, a user-controlled and automatically and / or autonomously operated mobile medical device. The mobile medical device has a chassis, the chassis comprising at least three wheels and / or at least two axles. It may be provided that driven and non-driven wheels are present. The mobile medical device includes a drive unit, the drive unit being configured to drive at least one of the wheels and / or at least one of the axles. In particular, "driving" can be understood to mean both acceleration and braking. For example, it is provided that, with active control by a user, or...In user-controlled mode of the mobile medical device, the wheels and / or axles are actively driven so that the mobile medical device maintains a speed greater than zero. It is provided that, for example, in automatic and / or autonomous operation of the mobile medical device, the drive unit brakes the wheel(s) and / or axles, bringing the mobile medical device to a standstill. The drive unit preferably comprises at least one electric motor. The drive unit can be configured to drive axles and / or wheels independently of each other.

[0028] The mobile medical device comprises an operating unit, the operating unit being configured as described in the context of the control unit. Furthermore, the mobile medical device comprises the control unit according to the invention. The operating unit is connected to the control unit via data transmission and is configured to provide the actuation data. The selection unit is configured to select, set, and / or apply one of the controller settings and / or controller behaviors based on the provided actuation data for the controller. In particular, the selection unit is configured to switch between the controller settings and / or controller behaviors of the controller based on the actuation data.

[0029] It is particularly preferred that the drive unit forms and / or includes a differential drive. The differential drive is configured to drive at least two wheels, preferably differently and / or with different degrees of force. The differential drive can, for example, be used to steer the mobile medical device. The controller is configured to regulate and / or control the differential drive, preferably to regulate and / or control the drive of individual wheels and / or axles, preferably differently and / or independently.

[0030] One embodiment of the invention provides that the control device is configured to regulate and / or control the drive parameters of the drive unit. The drive parameters describe, for example, the drive of a particular wheel and / or axle. For example, the drive parameters can describe whether the acceleration is positive or negative, a target speed, or an axle or wheel position. The drive parameters preferably include the position and / or speed of an axle and / or wheel. For example, the drive parameters describe parameters of the controller's control loop.

[0031] A particularly preferred embodiment of the invention provides that the control device comprises at least one input means for inputting user control data. The input means can, for example, include a joystick, a steering wheel, a slider or rotary control, a switch, a contact sensor, or a touchscreen. The user control data can, for example, describe the strength of the drive's acceleration, the desired speed of the mobile medical device, the direction (steering angle), and other information necessary for the user to steer and control the device.

[0032] The controller is preferably designed such that, in the first controller setting and / or first controller behavior, it regulates and / or controls the drive unit independently of the user control data. Furthermore, the controller may be designed such that, in the first controller setting and / or first controller behavior, it does not evaluate or use the user control data for control. The first controller setting and / or first controller behavior, in which the user control data does not contribute to the control, corresponds in particular to a PI controller, a PID controller, or a controller with a non-zero integration component. This is possible because the integration component can be perceived as undesirable when controlled by the user, whereas it has no negative effects in a control system that is independent of the user.

[0033] In this configuration, it is further preferably provided that in the second controller setting, the user control data serves as the basis for the control and / or regulation of the drive unit. In particular, in the second controller setting, the user control data is evaluated and / or used in the controller and influences the actuation, control, and regulation of the drive unit. It is specifically provided that in the second controller setting, where the user control data is incorporated into the control process, a controller behavior of a PL controller or a P controller with a small integration component or no integration component is used. By using a controller behavior with a small integration component or no integration component, the user perceives the control behavior of the controller in the second controller setting as particularly pleasant.This design makes it possible to optimally control the mobile medical device depending on the use of the user control data.

[0034] It is particularly preferred that the user control data include input speed, input direction, input position, input guidance and / or input acceleration.

[0035] It is particularly preferred that the control unit includes a dead man's switch. The dead man's switch can, for example, include a dead man's switch or a sensor that detects contact with an active user. The dead man's switch is configured to provide dead man's switch data that describes whether there is active user input, such as whether a user wants to control, regulate, and / or operate the mobile medical device, or whether no such active user is present. If, for example, there is no active user, the mobile medical device is intended to be actively braked to prevent any safety hazards to patients, operators, people, or objects in the vicinity. However, if there is active user input, the drive unit should follow the user's commands. The input data includes the dead man's switch data.The control unit is designed to select or apply a controller setting for user-based control when active user input is present. However, if no active user input is present, the control unit is designed to select and / or set a controller setting for automatic control.

[0036] Preferably, the controller setting for user-based control corresponds to the second controller setting and / or a PL controller or a PI controller with a small I component.

[0037] Furthermore, it is preferably provided that the controller setting for automatic control corresponds to the first controller setting or to the behavior of a PI controller.

[0038] The controller is particularly preferably designed to use the user control data as a basis for regulating and / or controlling the drive unit when user-based control is available.

[0039] It is particularly preferred that the mobile medical device constitutes a mobile imaging unit such as a mobile C-arm or a mobile head scanner. These medical devices have a high weight, and the behavior of the control unit according to the invention results in particularly convenient and safe mobility of the medical device.

[0040] A further aspect of the invention is a method for controlling and / or actuating a drive unit of a real medical device. An operating unit of the mobile medical device provides actuation data to the selection unit of the control unit. Based on the actuation data, the selection unit chooses a controller setting for the controller of the control unit, sets and / or uses the selected controller setting.

[0041] Further advantages, effects, and embodiments of the invention will become apparent from the accompanying figures and their description. These show: Fig. 1 an embodiment of a mobile medical device; Fig. 2 a section of a control loop comprising an embodiment of the control device; Fig. 3. A flowchart to illustrate the control device.

[0042] Fig. Figure 1 shows a mobile medical device, which is designed, for example, as a mobile head scanner or a mobile C-arm. The actual imaging unit, for example, the C-arm, can be mounted on a mobile platform. The mobile medical device 1 is controllable by a user 2, in particular, it can be moved and / or steered. For this purpose, the mobile medical device 1 includes an operating device 3. The operating device 3 can, for example, include force sensors, which preferably serve as a dead man's switch. Furthermore, the operating device 3 can include at least one input means, for example, a joystick, buttons, or a steering wheel, with which the user 2 can control and / or steer the movement, propulsion, and / or travel of the mobile medical device 1.

[0043] The mobile medical device 1 comprises a chassis, which may, for example, include and / or be connected to a frame structure. The chassis and / or the mobile medical device 1 comprise a plurality of wheels 4a to 4d, wherein wheels 4a and 4b are driven wheels and wheels 4c and 4d are stationary support wheels. Wheels 4a and 4b are connected to a drive unit 5, for example, via an axle 6. The drive unit 5 is configured to drive and / or brake wheels 4a and 4b. The drive unit 5 is preferably a differential drive, so that wheels 4a and 4b can be driven with different speeds to enable cornering, for example, around the angle ω, by means of different rotational speeds of the wheels 4a and 4b. In particular, the user 2 can set and / or select a target speed and / or select and / or set the steering angle ω.

[0044] The operating device 3 is configured to provide actuation data 7, wherein the actuation data 7 includes, for example, information about whether the dead man's switch is activated and / or whether contact with the user 2 exists, or whether the user 2 is no longer in contact with the operating device 3 and no longer actively takes over control. The actuation data 7 may also include user control data 8, which includes a target speed and / or a steering angle.

[0045] The mobile medical device 1 includes a control unit 9, which is arranged in the data stream between the operating unit 3 and the drive unit 5.

[0046] To illustrate the processes for regulating and / or controlling the mobile medical device 1 by the control unit 9, Figure 9 shows Fig. Figure 2 shows an excerpt from the data and / or signal connections of the control unit 9. The control unit 9 is connected to the operating unit 3 and the drive unit 5 via data connections. For this purpose, the control unit 9 has a data input 10a and a data output 10b. The operating unit 3 provides actuation data 7 to the control unit 9 at data input 10a. This actuation data 7 can include user control data 8 and / or deadman data. At data output 10b, the control unit 9 provides controller and / or control signals for regulating and / or controlling the drive unit 5. The drive unit 5 reacts to the provided signals by adjusting the drive parameters 11, for example, by adjusting the rotational speed of the wheels 4a and 4b.

[0047] The control unit 9 comprises a selection unit 12 and a controller 13. The selection unit 12 is preferably connected to the data input 10a. In particular, the selection unit 12 is arranged between the data input 10a and the controller 13. The operating data 7 is provided to the selection unit 12. Based on the operating data 7, it selects from at least two possible controller settings a controller setting to be used and / or set for the controller 13. In particular, the selection unit 12 selects the optimal and / or most suitable controller settings for the currently available operating data 7 and communicates these to the controller 13. For this purpose, the selection unit 12 can, for example, use a parameter set, preferably comprising K I and K P, and / or provide and / or communicate the controller setting to controller 13. Controller 13 then uses the selected controller setting to regulate and / or control the drive unit 5. In addition to the controller setting, controller 13 also uses the user control data 8 when actively controlled by user 2, whereas in automatic control (i.e., control without user 2), the user control data 8 is not used by the controller to regulate or control the drive unit 5.

[0048] This shows Fig.Figure 3 schematically illustrates the sequence of processes and / or operations in the control unit 9. In state 100, the operating unit 3 is operated by the user and / or the deadman data confirms that an active user is present. Furthermore, the actuation data 7 includes user control data 8, which describes the control request of the user 2. In this state, where the deadman unit is operated by the user, the selection unit 12 initiates the use of the second controller setting, which provides a low integration factor, so that the controller can react to the user control data 8 with a short time delay. Based on this data, the controller then controls the drive unit 5.

[0049] In state 200, it is detected that the dead man's switch has been released by user 2, necessitating a switch from user-based control to automatic control. For this purpose, selection unit 12 instructs controller 13 to use the first controller setting, which has a higher integration factor. After instructing controller 13 to use the first controller setting, it no longer uses user control data 8, but rather braking control data, which, for example, specifies the maximum permissible braking of the mobile medical device 1. This data provision can be performed by selection unit 12 and / or may already be integrated into controller 13.

[0050] In state 400, it is detected that user 2 has again activated the deadman's switch. Selection unit 12 then causes the controller to revert to the second controller setting, and the control system returns to state and / or step 100, in which user control data 8 is again used for control and / or regulation.

Claims

[1] Control device (9) for a mobile medical device (1), wherein the control device (9) comprises a controller (13) and a selection unit (12), wherein the controller (13) is configured to control and / or regulate a drive unit (5) of the mobile medical device (1), wherein the mobile medical device (1) comprises an operating device (3) for operation by a user (2), wherein the control device (9) is provided with operating data (7) from the operating device (3), characterized by , that the controller (13) has at least two different controller settings, wherein the selection unit (12) is configured to select, set and / or use the controller setting based on the actuation data (7). [2] Control device (9) according to claim 1, characterized by, that the controller settings comprise a first controller setting with a first controller behavior and a second controller setting with a second controller behavior, wherein the selection unit (12) is configured to select, set and / or use the first or the second controller setting based on the actuation data (7). [3] Control device (9) according to claim 2, characterized by , that the initial controller behavior of the first controller setting corresponds to a PI controller. [4] Control device (9) according to claim 2 or 3, characterized by , that the second controller behavior of the second controller setting corresponds to a P controller or to a PL controller with a lower I component than the PI controller of the first controller setting. [5] Mobile medical device (1) comprising a chassis with wheels (4, 4a, b, c, d), a drive unit (5), an operating device (3) and a control device (9) according to one of the preceding claims, wherein the drive unit (5) is configured to drive at least one wheel (4a, b) of the wheels (4a, b, c, d), wherein the operating device (3) is configured to provide actuation data (7) to the control device (9), wherein the controller (9) has at least two different controller settings, wherein the selection unit (12) is configured to select, set and / or use the controller setting based on the actuation data (7). [6] Mobile medical device (1) according to claim 5, characterized by , that the drive unit (5) forms a differential drive for driving at least two wheels (4a, b). [7] Mobile medical device (1) according to claim 5 or 6, characterized by, that the control device (9) is configured to regulate and / or control drive parameters (11) of the drive unit (5), wherein the drive parameters include a position and / or speed of an axle and / or a wheel. [8] Mobile medical device (1) according to any one of claims 5 to 7, characterized by , that the controller settings comprise a first controller setting with a first controller behavior and a second controller setting with a second controller behavior, wherein the selection unit (12) is configured to select, set and / or use the first or the second controller setting based on the actuation data (7). [9] Mobile medical device (1) according to claim 8, characterized by, that the operating device (3) includes at least one input means for inputting user control data (8), wherein the controller (13) is configured to regulate and / or control the drive unit independently of the user control data (8) in the first controller setting and / or to use the user control data (8) as a basis for regulating and / or controlling the drive unit (5) in the second controller setting. [10] Mobile medical device (1) according to claim 9, characterized by , that the user control data (8) include an input speed, an input direction and / or an input position. [11] Mobile medical device (1) according to any one of claims 5 to 10, characterized by, that the operating device (3) includes a dead man's unit, wherein the dead man's unit is configured to provide dead man's data, wherein dead man's data describes whether there is an active user operation or not, wherein the operation data includes the dead man's data, wherein the control device (9) is configured to select, set and / or use a controller setting for user-based control when there is an active user operation and / or to count, set and / or use a controller setting for automatic control when there is no active user operation. [12] Mobile medical device (1) according to claim 11, characterized by , that the controller setting for user-based control corresponds to the second controller setting, a P controller and / or a PI controller with a smaller I-component than the first controller setting. [13] Mobile medical device (1) according to claim 11 or 12, characterized by, that the controller setting corresponds to the first controller setting and / or a PI controller for automatic control. [14] Mobile medical device (1) according to any one of claims 11 to 13, characterized by , that, the controller (13) is designed to use the user control data (8) as a basis for regulating and / or controlling the drive unit (5) in the case of user-based control and / or to control the drive unit (5) in the case of automatic control to brake the mobile medical device (1). [15] Mobile medical device (1) according to any one of claims 5 to 14, wherein the mobile medical device (1) comprises a mobile head scanner, a mobile C-arm, a mobile patient bed and / or a mobile imaging device.

Images