Patent Description:
The present invention relates generally to the field of robotic medical procedure systems and, in particular, to a support for securing a robotic system to a patient table.

Catheters and other elongated medical devices (EMDs) may be used for minimally-invasive medical procedures for the diagnosis and treatment of diseases of various vascular systems, including neurovascular intervention (NVI) also known as neurointerventional surgery, percutaneous coronary intervention (PCI) and peripheral vascular intervention (PVI). These procedures typically involve navigating a guidewire through the vasculature, and via the guidewire advancing a catheter to deliver therapy. The catheterization procedure starts by gaining access into the appropriate vessel, such as an artery or vein, with an introducer sheath using standard percutaneous techniques. Through the introducer sheath, a sheath or guide catheter is then advanced over a diagnostic guidewire to a primary location such as an internal carotid artery for NVI, a coronary ostium for PCI, or a superficial femoral artery for PVI. A guidewire suitable for the vasculature is then navigated through the sheath or guide catheter to a target location in the vasculature. In certain situations, such as in tortuous anatomy, a support catheter or microcatheter is inserted over the guidewire to assist in navigating the guidewire. The physician or operator may use an imaging system (e.g., fluoroscope) to obtain a cine with a contrast injection and select a fixed frame for use as a roadmap to navigate the guidewire or catheter to the target location, for example, a lesion. Contrast-enhanced images are also obtained while the physician delivers the guidewire or catheter so that the physician can verify that the device is moving along the correct path to the target location. While observing the anatomy using fluoroscopy, the physician manipulates the proximal end of the guidewire or catheter to direct the distal tip into the appropriate vessels toward the lesion or target anatomical location and avoid advancing into side branches.

Document <CIT> discloses a hand table assembly comprising a hand table, which can be removably mounted to a main surgical table.

Document <CIT> discloses an elongated support member with an inflatable bladder which can be attached to a pivotal operating room table to support a patient in order to reduce the risk for the patient to suffer compressions or stretching.

Robotic catheter-based procedure systems have been developed that may be used to aid a physician in performing catheterization procedures such as, for example, NVI, PCI and PVI. Examples of NVI procedures include coil embolization of aneurysms, liquid embolization of arteriovenous malformations and mechanical thrombectomy of large vessel occlusions in the setting of acute ischemic stroke. In an NVI procedure, the physician uses a robotic system to gain target lesion access by controlling the manipulation of a neurovascular guidewire and microcatheter to deliver the therapy to restore normal blood flow. Target access is enabled by the sheath or guide catheter but may also require an intermediate catheter for more distal territory or to provide adequate support for the microcatheter and guidewire. The distal tip of a guidewire is navigated into, or past, the lesion depending on the type of lesion and treatment. For treating aneurysms, the microcatheter is advanced into the lesion and the guidewire is removed and several embolization coils are deployed into the aneurysm through the microcatheter and used to block blood flow into the aneurysm. For treating arteriovenous malformations, a liquid embolic is injected into the malformation via a microcatheter. Mechanical thrombectomy to treat vessel occlusions can be achieved either through aspiration and/or use of a stent retriever. Depending on the location of the clot, aspiration is either done through an aspiration catheter, or through a microcatheter for smaller arteries. Once the aspiration catheter is at the lesion, negative pressure is applied to remove the clot through the catheter. Alternatively, the clot can be removed by deploying a stent retriever through the microcatheter. Once the clot has integrated into the stent retriever, the clot is retrieved by retracting the stent retriever and microcatheter (or intermediate catheter) into the guide catheter.

In PCI, the physician uses a robotic system to gain lesion access by manipulating a coronary guidewire to deliver the therapy and restore normal blood flow. The access is enabled by seating a guide catheter in a coronary ostium. The distal tip of the guidewire is navigated past the lesion and, for complex anatomies, a microcatheter may be used to provide adequate support for the guidewire. The blood flow is restored by delivering and deploying a stent or balloon at the lesion. The lesion may need preparation prior to stenting, by either delivering a balloon for pre-dilation of the lesion, or by performing atherectomy using, for example, a laser or rotational atherectomy catheter and a balloon over the guidewire. Diagnostic imaging and physiological measurements may be performed to determine appropriate therapy by using imaging catheters or fractional flow reserve (FFR) measurements.

In PVI, the physician uses a robotic system to deliver the therapy and restore blood flow with techniques similar to NVI. The distal tip of the guidewire is navigated past the lesion and a microcatheter may be used to provide adequate support for the guidewire for complex anatomies. The blood flow is restored by delivering and deploying a stent or balloon to the lesion. As with PCI, lesion preparation and diagnostic imaging may be used as well.

When support at the distal end of a catheter or guidewire is needed, for example, to navigate tortuous or calcified vasculature, to reach distal anatomical locations, or to cross hard lesions, an over-the-wire (OTW) catheter or coaxial system is used. An OTW catheter has a lumen for the guidewire that extends the full length of the catheter. This provides a relatively stable system because the guidewire is supported along the whole length. This system, however, has some disadvantages, including higher friction, and longer overall length compared to rapid-exchange catheters (see below). Typically to remove or exchange an OTW catheter while maintaining the position of the indwelling guidewire, the exposed length (outside of the patient) of guidewire must be longer than the OTW catheter. A <NUM> long guidewire is typically sufficient for this purpose and is often referred to as an exchange length guidewire. Due to the length of the guidewire, two operators are needed to remove or exchange an OTW catheter. This becomes even more challenging if a triple coaxial, known in the art as a triaxial system, is used (quadruple coaxial catheters have also been known to be used). However, due to its stability, an OTW system is often used in NVI and PVI procedures. On the other hand, PCI procedures often use rapid exchange (or monorail) catheters. The guidewire lumen in a rapid exchange catheter runs only through a distal section of the catheter, called the monorail or rapid exchange (RX) section. With a RX system, the operator manipulates the interventional devices parallel to each other (as opposed to with an OTW system, in which the devices are manipulated in a serial configuration), and the exposed length of guidewire only needs to be slightly longer than the RX section of the catheter. A rapid exchange length guidewire is typically <NUM>-<NUM> long. Given the shorter length guidewire and monorail, RX catheters can be exchanged by a single operator. However, RX catheters are often inadequate when more distal support is needed.

In accordance with an implementation a support attaches a mechanism to a patient table having a patient supporting surface and a first rail and a second rail. The support comprising: a base comprising; a first engagement member; a second engagement member; and a single engagement mechanism moving the first engagement member and the second engagement member from a loading position to a secured position securing the base to the first rail and the second rail.

In one implementation the first engagement member is configured to contact a bottom of the first rail and the second engagement member is configured to contact a bottom of the second rail in the secured position.

In one implementation the base includes a first pad contacting the patient supporting surface.

In one implementation the first pad is biased by a biasing member applying a pad force to the patient supporting table.

In one implementation the pad force is substantially constant.

In one implementation the single engagement mechanism secures the base in a cross-table direction, parallel to a patient table plane defining the patient supporting surface, and in a vertical direction perpendicular to the patient supporting surface.

In one implementation the single engagement mechanism includes a cam mechanism having a first cam surface moving the base in the cross-table direction.

In one implementation the cam mechanism includes a second cam surface moving the base in the vertical direction.

In one implementation a medical device system is attached to the support, the medical device system having a center of mass providing a system force onto the first rail and second rail, wherein the pad force and the system force does not exceed a predetermined limit force on the first rail, the second rail and the patient supporting surface.

In one implementation the center of mass of the medical device system moves within a predefined region during active operation of the medical device system and wherein the predetermined force is not exceeded.

In one implementation the first pad contacts the patient supporting surface closer to the first rail than the second rail.

In one implementation the first pad contacts the patient supporting surface intermediate the first rail and the second rail.

In one implementation the patient table includes a table marker, and the base includes a base marker, wherein the base marker is aligned with the table marker in the secured position.

In one implementation the single engagement mechanism is actuated by movement of a member in a single direction.

In one implementation an arm is integrated with the base, wherein the base is configured to be removably lowered onto the patient table, to the patient supporting surface.

In one implementation a support attaches a mechanism to a patient table having a patient supporting surface and a first rail and a second rail. The support comprising: a base including a pad positioned intermediate the first rail and the second rail, the pad biased by a biasing member in a first direction, the first pad configured to contact the patient supporting surface of the patient table. A first engagement member is configured to contact the first rail; and a second engagement member is configured to contact the second rail. The pad applies a pad force to the patient supporting surface when the pad is contact with the patient supporting surface.

In one implementation a stop member is connected to the base, the stop member limiting a distance the pad can extend in the first direction and maintaining the biasing member in a preloaded state when the pad is not in contact with the patient supporting surface.

In one implementation a full force of the biasing member is applied to the patient supporting surface when the pad contacts the patient supporting surface and the pad moves in a second direction away from the stop member.

In one implementation a medical device system configured to be attached to the support, the medical device system having a center of mass providing a system force onto the first rail and the second rail, wherein the pad force and the system force does not exceed a predetermined limit force on the first rail, the second rail and the patient supporting surface, wherein the force of the support and the medical device system is distributed between the first rail, the second rail, and the patient supporting surface.

In one implementation a medical device system configured to be attached to the support, the medical device system having a center of mass providing a system force onto the first rail and the second rail, wherein the pad force and the system force does not exceed a predetermined limit force on the first rail, the second rail and the patient supporting surface.

The invention will become more fully understood from the following detailed description, taken in conjunction with the accompanying drawings, wherein the like reference numerals refer to like parts in which:.

<FIG> is a perspective view of an example catheter-based procedure system <NUM> in accordance with an embodiment. Catheter-based procedure system <NUM> may be used to perform catheter-based medical procedures, e.g., percutaneous intervention procedures such as a percutaneous coronary intervention (PCI) (e.g., to treat STEMI), a neurovascular interventional procedure (NVI) (e.g., to treat an emergent large vessel occlusion (ELVO)), peripheral vascular intervention procedures (PVI) (e.g., for critical limb ischemia (CLI), etc.). Catheter-based medical procedures may include diagnostic catheterization procedures during which one or more catheters or other elongated medical devices (EMDs) are used to aid in the diagnosis of a patient's disease. For example, during one embodiment of a catheter-based diagnostic procedure, a contrast media is injected onto one or more arteries through a catheter and an image of the patient's vasculature is taken. Catheter-based medical procedures may also include catheter-based therapeutic procedures (e.g., angioplasty, stent placement, treatment of peripheral vascular disease, clot removal, arterial venous malformation therapy, treatment of aneurysm, etc.) during which a catheter (or other EMD) is used to treat a disease. Therapeutic procedures may be enhanced by the inclusion of adjunct devices <NUM> (shown in <FIG>) such as, for example, intravascular ultrasound (IVUS), optical coherence tomography (OCT), fractional flow reserve (FFR), etc. It should be noted, however, that one skilled in the art would recognize that certain specific percutaneous intervention devices or components (e.g., type of guidewire, type of catheter, etc.) may be selected based on the type of procedure that is to be performed. Catheter-based procedure system <NUM> can perform any number of catheter-based medical procedures with minor adjustments to accommodate the specific percutaneous intervention devices to be used in the procedure.

Catheter-based procedure system <NUM> includes, among other elements, a bedside unit <NUM> and a control station (not shown). Bedside unit <NUM> includes a robotic drive <NUM> and a positioning system <NUM> that are located adjacent to a patient <NUM>. Patient <NUM> is supported on a patient table <NUM>. The positioning system <NUM> is used to position and support the robotic drive <NUM>. The positioning system <NUM> may be, for example, a robotic arm, an articulated arm, a holder, etc. The positioning system <NUM> may be attached at one end to, for example, the patient table <NUM> (as shown in <FIG>), a base, or a cart. The other end of the positioning system <NUM> is attached to the robotic drive <NUM>. The positioning system <NUM> may be moved out of the way (along with the robotic drive <NUM>) to allow for the patient <NUM> to be placed on the patient table <NUM>. Once the patient <NUM> is positioned on the patient table <NUM>, the positioning system <NUM> may be used to situate or position the robotic drive <NUM> relative to the patient <NUM> for the procedure. In an embodiment, patient table <NUM> is operably supported by a pedestal <NUM>, which is secured to the floor and/or earth. Patient table <NUM> is able to move with multiple degrees of freedom, for example, roll, pitch, and yaw, relative to the pedestal <NUM>. Bedside unit <NUM> may also include controls and displays <NUM> (shown in <FIG>). For example, controls and displays may be located on a housing of the robotic drive <NUM>.

Generally, the robotic drive <NUM> may be equipped with the appropriate percutaneous interventional devices and accessories <NUM> (shown in <FIG>) (e.g., guidewires, various types of catheters including balloon catheters, stent delivery systems, stent retrievers, embolization coils, liquid embolics, aspiration pumps, device to deliver contrast media, medicine, hemostasis valve adapters, syringes, stopcocks, inflation device, etc.) to allow a user or operator to perform a catheter-based medical procedure via a robotic system by operating various controls such as the controls and inputs located at the control station. Bedside unit <NUM>, and in particular robotic drive <NUM>, may include any number and/or combination of components to provide bedside unit <NUM> with the functionality described herein. The robotic drive <NUM> includes a plurality of device modules 32a-d mounted to a rail or linear member. Each of the device modules 32a-d may be used to drive an EMD such as a catheter or guidewire. For example, the robotic drive <NUM> may be used to automatically feed a guidewire into a diagnostic catheter and into a guide catheter in an artery of the patient <NUM>. One or more devices, such as an EMD, enter the body (e.g., a vessel) of the patient <NUM> at an insertion point <NUM> via, for example, an introducer sheath.

Bedside unit <NUM> is in communication with the control station (not shown), allowing signals generated by the user inputs of the control station to be transmitted wirelessly or via hardwire to the bedside unit <NUM> to control various functions of bedside unit <NUM>. As discussed below, control station <NUM> may include a control computing system <NUM> (shown in <FIG>) or be coupled to the bedside unit <NUM> through the control computing system <NUM>. Bedside unit <NUM> may also provide feedback signals (e.g., loads, speeds, operating conditions, warning signals, error codes, etc.) to the control station, control computing system <NUM> (shown in <FIG>), or both. Communication between the control computing system <NUM> and various components of the catheter-based procedure system <NUM> may be provided via a communication link that may be a wireless connection, cable connections, or any other means capable of allowing communication to occur between components. The control station or other similar control system may be located either at a local site (e.g., local control station <NUM> shown in <FIG>) or at a remote site (e.g., remote control station and computer system <NUM> shown in <FIG>). Catheter procedure system <NUM> may be operated by a control station at the local site, a control station at a remote site, or both the local control station and the remote control station at the same time. At a local site, a user or operator and the control station are located in the same room or an adjacent room to the patient <NUM> and bedside unit <NUM>. As used herein, a local site is the location of the bedside unit <NUM> and a patient <NUM> or subject (e.g., animal or cadaver) and the remote site is the location of a user or operator and a control station used to control the bedside unit <NUM> remotely. A control station (and a control computing system) at a remote site and the bedside unit <NUM> and/or a control computing system at a local site may be in communication using communication systems and services <NUM> (shown in <FIG>), for example, through the Internet. In an embodiment, the remote site and the local (patient) site are away from one another, for example, in different rooms in the same building, different buildings in the same city, different cities, or other different locations where the remote site does not have physical access to the bedside unit <NUM> and/or patient <NUM> at the local site.

The control station generally includes one or more input modules <NUM> configured to receive user inputs to operate various components or systems of catheter-based procedure system <NUM>. In the embodiment shown, control station allows the user or operator to control bedside unit <NUM> to perform a catheter-based medical procedure. For example, input modules <NUM> may be configured to cause bedside unit <NUM> to perform various tasks using percutaneous intervention devices (e.g., EMDs) interfaced with the robotic drive <NUM> (e.g., to advance, retract, or rotate a guidewire, advance, retract or rotate a catheter, inflate or deflate a balloon located on a catheter, position and/or deploy a stent, position and/or deploy a stent retriever, position and/or deploy a coil, inject contrast media into a catheter, inject liquid embolics into a catheter, inject medicine or saline into a catheter, aspirate on a catheter, or to perform any other function that may be performed as part of a catheter-based medical procedure). Robotic drive <NUM> includes various drive mechanisms to cause movement (e.g., axial and rotational movement) of the components of the bedside unit <NUM> including the percutaneous intervention devices.

In one embodiment, input modules <NUM> may include one or more touch screens, joysticks, scroll wheels, and/or buttons. In addition to input modules <NUM>, the control station <NUM> may use additional user controls <NUM> (shown in <FIG>) such as foot switches and microphones for voice commands, etc. Input modules <NUM> may be configured to advance, retract, or rotate various components and percutaneous intervention devices such as, for example, a guidewire, and one or more catheters or microcatheters. Buttons may include, for example, an emergency stop button, a multiplier button, device selection buttons and automated move buttons. When an emergency stop button is pushed, the power (e.g., electrical power) is shut off or removed to bedside unit <NUM>. When in a speed control mode, a multiplier button acts to increase or decrease the speed at which the associated component is moved in response to a manipulation of input modules <NUM>. When in a position control mode, a multiplier button changes the mapping between input distance and the output commanded distance. Device selection buttons allow the user or operator to select which of the percutaneous intervention devices loaded into the robotic drive <NUM> are controlled by input modules <NUM>. Automated move buttons are used to enable algorithmic movements that the catheter-based procedure system <NUM> may perform on a percutaneous intervention device without direct command from the user or operator <NUM>. In one embodiment, input modules <NUM> may include one or more controls or icons (not shown) displayed on a touch screen (that may or may not be part of a display), that, when activated, causes operation of a component of the catheter-based procedure system <NUM>. Input modules <NUM> may also include a balloon or stent control that is configured to inflate or deflate a balloon and/or deploy a stent. Each of the input modules <NUM> may include one or more buttons, scroll wheels, joysticks, touch screen, etc. that may be used to control the particular component or components to which the control is dedicated. In addition, one or more touch screens may display one or more icons (not shown) related to various portions of input modules <NUM> or to various components of catheter-based procedure system <NUM>.

Catheter-based procedure system <NUM> also includes an imaging system <NUM>. Imaging system <NUM> may be any medical imaging system that may be used in conjunction with a catheter based medical procedure (e.g., non-digital X-ray, digital X-ray, CT, MRI, ultrasound, etc.). In an exemplary embodiment, imaging system <NUM> is a digital X-ray imaging device that is in communication with the control station. In one embodiment, imaging system <NUM> may include a C-arm (shown in <FIG>) that allows imaging system <NUM> to partially or completely rotate around patient <NUM> in order to obtain images at different angular positions relative to patient <NUM> (e.g., sagittal views, caudal views, anterior-posterior views, etc.). In one embodiment imaging system <NUM> is a fluoroscopy system including a C-arm having an X-ray source <NUM> and a detector <NUM>, also known as an image intensifier.

Imaging system <NUM> may be configured to take X-ray images of the appropriate area of patient <NUM> during a procedure. For example, imaging system <NUM> may be configured to take one or more X-ray images of the head to diagnose a neurovascular condition. Imaging system <NUM> may also be configured to take one or more X-ray images (e.g., real time images) during a catheter-based medical procedure to assist the user or operator <NUM> of control station <NUM> to properly position a guidewire, guide catheter, microcatheter, stent retriever, coil, stent, balloon, etc. during the procedure. The image or images may be displayed on display <NUM>. For example, images may be displayed on a display to allow the user or operator to accurately move a guide catheter or guidewire into the proper position.

In order to clarify directions, a rectangular coordinate system is introduced with X, Y, and Z axes. The positive X axis is oriented in a longitudinal (axial) distal direction, that is, in the direction from the proximal end to the distal end, stated another way from the proximal to distal direction. The Y and Z axes are in a transverse plane to the X axis, with the positive Z axis oriented up, that is, in the direction opposite of gravity, and the Y axis is automatically determined by right-hand rule.

<FIG> is a block diagram of catheter-based procedure system <NUM> in accordance with an example embodiment. Catheter-procedure system <NUM> may include a control computing system <NUM>. Control computing system <NUM> may physically be, for example, part of a control station. Control computing system <NUM> may generally be an electronic control unit suitable to provide catheter-based procedure system <NUM> with the various functionalities described herein. For example, control computing system <NUM> may be an embedded system, a dedicated circuit, a general-purpose system programmed with the functionality described herein, etc. Control computing system <NUM> is in communication with bedside unit <NUM>, communications systems and services <NUM> (e.g., Internet, firewalls, cloud services, session managers, a hospital network, etc.), a local control station <NUM>, additional communications systems <NUM> (e.g., a telepresence system), a remote control station and computing system <NUM>, and patient sensors <NUM> (e.g., electrocardiogram (ECG) devices, electroencephalogram (EEG) devices, blood pressure monitors, temperature monitors, heart rate monitors, respiratory monitors, etc.). The control computing system is also in communication with imaging system <NUM>, patient table <NUM>, additional medical systems <NUM>, contrast injection systems <NUM> and adjunct devices <NUM> (e.g., IVUS, OCT, FFR, etc.). The bedside unit <NUM> includes a robotic drive <NUM>, a positioning system <NUM> and may include additional controls and displays <NUM>. As mentioned above, the additional controls and displays may be located on a housing of the robotic drive <NUM>. Interventional devices and accessories <NUM> (e.g., guidewires, catheters, etc.) interface to the bedside system <NUM>. In an embodiment, interventional devices and accessories <NUM> may include specialized devices (e.g., IVUS catheter, OCT catheter, FFR wire, diagnostic catheter for contrast, etc.) which interface to their respective adjunct devices <NUM>, namely, an IVUS system, an OCT system, and FFR system, etc..

In various embodiments, control computing system <NUM> is configured to generate control signals based on the user's interaction with input modules <NUM> (e.g., of a control station such as a local control station <NUM> or a remote control station <NUM>) and/or based on information accessible to control computing system <NUM> such that a medical procedure may be performed using catheter-based procedure system <NUM>. The local control station <NUM> includes one or more displays <NUM>, one or more input modules <NUM>, and additional user controls <NUM>. The remote control station and computing system <NUM> may include similar components to the local control station <NUM>. The remote <NUM> and local <NUM> control stations can be different and tailored based on their required functionalities. The additional user controls <NUM> may include, for example, one or more foot input controls. The foot input control may be configured to allow the user to select functions of the imaging system <NUM> such as turning on and off the X-ray and scrolling through different stored images. In another embodiment, a foot input device may be configured to allow the user to select which devices are mapped to scroll wheels included in input modules <NUM>. Additional communication systems <NUM> (e.g., audio conference, video conference, telepresence, etc.) may be employed to help the operator interact with the patient, medical staff (e.g., angio-suite staff), and/or equipment in the vicinity of the bedside.

Catheter-based procedure system <NUM> may be connected or configured to include any other systems and/or devices not explicitly shown. For example, catheter-based procedure system <NUM> may include image processing engines, data storage and archive systems, automatic balloon and/or stent inflation systems, medicine injection systems, medicine tracking and/or logging systems, user logs, encryption systems, systems to restrict access or use of catheter-based procedure system <NUM>, etc..

As mentioned, control computing system <NUM> is in communication with bedside unit <NUM> which includes a robotic drive <NUM>, a positioning system <NUM> and may include additional controls and displays <NUM>, and may provide control signals to the bedside unit <NUM> to control the operation of the motors and drive mechanisms used to drive the percutaneous intervention devices (e.g., guidewire, catheter, etc.). The various drive mechanisms may be provided as part of a robotic drive <NUM>.

Referring now to <FIG>, a side view of the example catheter-based procedure system <NUM> of <FIG> is illustrated with certain components (e.g., patient, C-arm) removed for clarity. As described above with reference to <FIG>, the patient table <NUM> is supported on the pedestal <NUM>, and the robotic drive <NUM> is mounted to the patient table with a positioning system <NUM>. The positioning system <NUM> allows manipulation of the robotic drive <NUM> relative to the patient table <NUM>. In this regard, the positioning system <NUM> is securely mounted to the patient table <NUM> and includes various joints and links/arms to allow the manipulation, as described below with reference to <FIG>.

<FIG> is a perspective view of an example positioning system <NUM> for a robotic drive in accordance with an embodiment. The positioning system <NUM> includes a mounting arrangement <NUM> to securely mount the positioning system <NUM> to the patient table <NUM>. The mounting arrangement <NUM> includes an engagement mechanism to engage a first engagement member with a first longitudinal rail and a second engagement member with a second longitudinal rail to removably secure the positioning system to the patient bed.

The positioning system <NUM> includes various segments and joints coupling to allow the robotic drive <NUM> to be positioned as desired, for example, relative to the patient. The positioning system <NUM> includes a first rotational joint <NUM> coupled to the mounting arrangement <NUM>. The first rotational joint <NUM> allows rotation of a first arm <NUM>, or link, about a rotational axis. In the illustrated example, the mounting arrangement <NUM> is in a substantially horizontal plane (e.g., the plane of the patient table <NUM>), and the rotational axis is substantially vertical and runs through the center of the first rotational joint <NUM>. The first rotational joint <NUM> can include circuitry to allow a user to control the rotation of the first rotational joint <NUM>.

In the illustrated example, the first arm <NUM> is substantially horizontal with a first end coupled to the first rotational joint <NUM>. The second end of the first arm <NUM> is coupled to a second rotational joint <NUM>. In addition, the second rotational joint <NUM> is also coupled to a first end of a second arm <NUM>. Thus, the second rotational joint <NUM> allows rotation of the second arm <NUM> relative to the first arm <NUM>. As with the first rotational joint <NUM>, the second rotational joint <NUM> allows rotation about a substantially vertical axis running through the center of the second rotational joint <NUM>. Further, the second rotational joint <NUM> can include circuitry to allow a user to control the rotation of the second rotational joint <NUM>.

In the illustrated example, a second end of the second arm <NUM> is coupled to a third rotational joint <NUM>. The third rotational joint <NUM> includes a post <NUM> to allow mounting of the robotic drive <NUM> to the positioning system <NUM>. Thus, the third rotational joint <NUM> allows rotation of the robotic drive <NUM> relative to the second arm <NUM>. The third rotational joint <NUM> allows rotation about a substantially vertical axis running through the center of the third rotational joint <NUM>. Further, the third rotational joint <NUM> can include circuitry to allow a user to control the rotation of the third rotational joint <NUM>.

In one example, the second arm <NUM> includes a <NUM>-arm linkage which can allow limited vertical movement of third rotational joint <NUM> relative to the second rotational joint <NUM>. In this regard, the <NUM>-arm linkage can allow vertical movement of the third rotational join <NUM>, while maintaining the substantially vertical orientation of the third rotational joint <NUM> and the post <NUM>.

Referring to <FIG> and <FIG> mounting arrangement <NUM> in one implementation includes a support <NUM> for attaching a mechanism such as a robotic drive <NUM> to a patient table <NUM> having a patient supporting surface <NUM> a first rail <NUM> and an opposing second rail <NUM>. Support <NUM> includes a base <NUM>. In one implementation base <NUM> includes an articulated arm <NUM> integrated therewith to support the mechanism such as robotic drive <NUM>. Support <NUM> includes a first engagement member <NUM> and a second engagement member <NUM>. An engagement mechanism <NUM> operatively moves first engagement member <NUM> and moves second engagement member <NUM> from a loading position to a secured position securing base <NUM> to first rail <NUM> and opposing second rail <NUM>.

Referring to <FIG> and <FIG> patient table <NUM> includes a patient supporting surface <NUM> having a first longitudinal end <NUM> and an opposing second longitudinal end <NUM>. In one implementation in an-use orientation a patient's head is closer to a second longitudinal end <NUM> than a first longitudinal end <NUM>, and the patient's feet are closer to the first longitudinal end <NUM> than to the opposing longitudinal end <NUM>. When a patient is lying face up on patient table <NUM> the patient's left side is proximate the first longitudinal side <NUM> and the patient's right side is proximate a second longitudinal side <NUM>. First rail <NUM> extends from an outer periphery of the first longitudinal side <NUM> away from the second longitudinal side <NUM>. Second rail <NUM> extends from an outer periphery of the second longitudinal side <NUM> in a direction away from first longitudinal side <NUM>.

In one in-use orientation patient supporting surface <NUM> is horizontal such that the direction of gravity is perpendicular to a plane defined by the patient supporting surface. Referring to the X, Y and Z axes the patient supporting surface is parallel to the X-Y plane. The direction perpendicular to the plane defined by the patient supporting surface is referred to herein as the vertical direction and movement along the vertical direction in the direction of gravity is referred to as lowering. Stated another way the vertical direction as used herein refers to direction along the Z axis. A surface of patient table <NUM> that faces away from the direction of gravity in the patient table in-use position is referred to as the upper surface and a surface that faces toward the direction of gravity in the patient table in-use position is referred to as the lower surface.

Referring <FIG> first rail <NUM> includes a first rail upper surface <NUM> and a first rail lower surface <NUM>, where the first rail upper surface <NUM> is closer to the patient table supporting surface <NUM> than the first rail lower surface <NUM>. Similarly, opposing second rail <NUM> includes a second rail upper surface <NUM> and an opposing second rail lower surface <NUM>, where the second rail upper surface <NUM> is closer to the patient table supporting surface <NUM> than the second rail lower surface <NUM>. First rail <NUM> includes an outer surface <NUM> extending between first rail upper surface <NUM> and first rail lower surface <NUM>. Outer surface <NUM> faces away from second rail <NUM>. Second rail <NUM> includes an outer surface <NUM>.

Referring to <FIG> Base <NUM> includes a cross-arm <NUM> supporting the second engagement member <NUM>. Cross-arm <NUM> slidably extends from a body <NUM> of base <NUM>. Cross-arm <NUM> can be adjusted relative to body <NUM> to accommodate patient beds having different cross-bed dimensions. First engagement member <NUM> can be adjusted in the vertical direction (Z-axis) by adjustment <NUM> connecting first engagement member housing <NUM> to body <NUM>. The cross-table direction is the direction extending perpendicular from outer surface <NUM> of first rail <NUM> toward outer surface <NUM> of second rail <NUM>. Second engagement member <NUM> includes a tab <NUM> that can be positioned along vertically extending member <NUM> of cross-arm <NUM>. Cross-arm <NUM> includes a first member <NUM> extending generally parallel to a plane defined by patient supporting surface <NUM>. The cross-table direction is along the Y axis. The positive Y axis direction or cross-table direction is the direction from the first rail <NUM> toward the second rail <NUM>. In one implementation first member <NUM> of cross-arm <NUM> telescopically extends from body <NUM> of base <NUM>. Vertically extending member <NUM> includes an engagement surface <NUM> facing toward patient second rail <NUM>. Member <NUM> extends in a downward direction away from patient supporting surface <NUM>. The position of tab <NUM> can be adjusted along the Z-axis direction to accommodate differing heights between second rail <NUM> and patient supporting surface <NUM>. Similarly, as noted above the engagement mechanism <NUM> can be adjusted along the Z-axis direction via adjustment <NUM> to accommodate differing heights between first rail <NUM> and patient supporting surface <NUM>.

In one implementation support <NUM> is placed on patient table <NUM> at a specific location along the longitudinal axis. A marker such as a table marker or other table indicia is placed at a specific location along the longitudinal axis of patient table <NUM>. Support <NUM> has indicia that is aligned with the table indicia so that the robotic mechanism can move within a predefined range of motion. The alignment of support <NUM> on patient table <NUM> as discussed aids in avoiding interference between robotic drive <NUM> and imaging system <NUM>. Additionally, alignment of support <NUM> on patient table <NUM> assists in positioning robotic drive <NUM> relative to a patient without running out of reach. In one implementation table marker may be permanently clamped to first rail <NUM> and table marker may include two portions that are located on either side longitudinally along first rail <NUM> along the X-axis such that engagement mechanism <NUM> is located between the two portions of the table marker.

Support <NUM> is lowered onto patient table <NUM> directly at the desired longitudinal position. Support <NUM> does not need to be installed at the distal end of patient table <NUM> and then slid along first rail <NUM> and second rail <NUM> to the desired longitudinal position. Similarly, removal of support <NUM> in one implementation as discussed herein upon release of first engagement member <NUM> and second engagement member <NUM> may be accomplished by raising the support away from patient table <NUM> without having to slide support along the longitudinal axis. In this manner support <NUM> is lowered to an in-use position at the desired position along the longitudinal axis of patient table <NUM> between the first longitudinal end <NUM> and opposing second longitudinal end <NUM>. Similarly, support <NUM> may be quickly removed from patient table <NUM> by raising the support <NUM> from patient table <NUM> without having to first slide support <NUM> toward either first longitudinal end <NUM> or opposing second longitudinal end <NUM>. This allows for quick removal from patient table <NUM> if the need should arise.

Referring to <FIG>, support <NUM> is lowered onto patient table <NUM> in a generally downward direction at a predetermined longitudinal position. In one implementation support <NUM> is lowered onto patient table <NUM> while cross-arm <NUM> is generally parallel to a plane defined by the patient supporting surface <NUM>. In another implementation a rest tab, support member or ledge <NUM> of first engagement member <NUM> rests on first rail upper surface <NUM> as support <NUM> is pivoted about first rail upper surface <NUM> until a portion of cross-arm <NUM> contacts patient supporting surface <NUM>. Both lowering support <NUM> along a vector parallel to a direction perpendicular to patient supporting surface <NUM> and lowering support <NUM> by first contacting ledge <NUM> of support <NUM> on first rail upper surface <NUM> and then lowering cross-arm onto patient supporting surface <NUM> results in support <NUM> being in a first loading position. In one implementation a user first lowers the region of support <NUM> proximate second engagement member <NUM> onto the region of patient table <NUM> proximate second rail <NUM> and then lower the first engagement member <NUM> toward first rail <NUM>.

Referring to <FIG> and <FIG> in a first position in which support <NUM> has been lowered onto patient <NUM> first engagement member <NUM> and second engagement member <NUM> are spaced from first rail <NUM> and second rail <NUM> respectively. Stated another way the distance between outer surface <NUM> of first rail <NUM> and outer surface <NUM> of second rail <NUM> is less than the distance between first engagement member <NUM> and second engagement member <NUM> in the cross-table direction.

Referring to <FIG> and <FIG> and <FIG> in a second position support is moved in the cross-table direction by engagement mechanism <NUM> such that outer surface <NUM> of first rail <NUM> and outer surface <NUM> of second rail <NUM> are contacted by engagement mechanism <NUM>. Referring to <FIG> in a third position support is moved further in a cross-table direction from first rail <NUM> toward second rail <NUM> and first engagement member <NUM> begins to contact first rail lower surface <NUM>.

Referring to <FIG> and <FIG> in the fully secured position, first engagement member <NUM> contacts first rail lower surface <NUM> and outer surface <NUM> of first rail <NUM> and second engagement member <NUM> contacts opposing second rail lower surface <NUM> and outer surface <NUM> of second engagement member <NUM>. In the fully secured position base <NUM> contacts patient supporting surface <NUM>. A first pad <NUM> extending from a lower surface of body <NUM> contacts patient supporting surface <NUM>. In one implementation in the fully secured position ledge <NUM> does not contact first rail upper surface <NUM> of first rail <NUM>. Stated another way in one implementation in the fully secured position support <NUM> does not contact second rail upper surface <NUM> and first rail upper surface <NUM>. However, in use first rail upper surface <NUM> does contact a portion <NUM> of support member <NUM> in response to a pitch moment. In one implementation by design there is a clearance between first rail upper surface <NUM> and portion <NUM> of support member <NUM> between <NUM> - <NUM>. In operation given however, portion <NUM> contacts first rail upper surface <NUM> on at least some longitudinal areas of first rail <NUM>. Note that the gap between first rail upper surface <NUM> and portion <NUM> can be adjusted by movement of support member <NUM> relative to first engagement member housing <NUM>. In one implementation support member <NUM> is attached to first engagement member housing <NUM> with a fastener and at least one shim maybe added or removed between support member <NUM> and first engagement member housing <NUM> to change the distance between support member <NUM> and first rail upper surface <NUM>. In one implementation in addition to first pad <NUM> a second pad <NUM> extending downwardly from support <NUM> contacts patient supporting surface <NUM>. Depending on the location of the force applied by support <NUM> a portion of support <NUM> does contact first rail upper surface <NUM>. Depending on the location of force second pad <NUM> may not contact patient supporting surface <NUM> and only one of the two cam assemblies contacts first rail <NUM> in the Z-axis direction. For certain locations of the force from support <NUM> both first pad <NUM> and second pad <NUM> and/or both cam assemblies contact patient supporting surface <NUM> and first rail <NUM> respectively.

Patient tables include a first and second longitudinally extending rail on the right side and left side of the patient table. A number of different devices are supported on the right and left rails. The first rail and the second rail can support a certain amount of mass before the force applied to the first rail and / or second rail lose their ability to positively locate the device relative to the patient supporting surface. While rails are often rated on weight the location of force of the devices secured to the rail may apply an undesirable torque to the rails. Devices that have significant mass may bend and/or torque the first rail <NUM> and/or second rail <NUM>. As further described herein first pad <NUM> is biased by a biasing member applying a pad force to patient supporting surface <NUM>. In one implementation the pad force is substantially constant during movement of the arm and robotic drive. The pad force acts to counter act the forces applied to patient table <NUM> from the support and robotic drive <NUM>. In one implementation springs <NUM> are preloaded so that as soon as the pad is displaced from the hard stops <NUM> the full force of springs <NUM> are applied.

Referring to <FIG>, <FIG>, <FIG>, <FIG> engagement mechanism <NUM> is a single engagement mechanism that moves first engagement member <NUM> and second engagement member <NUM> from the loading position to the secured position securing base <NUM> to first rail <NUM> and second rail <NUM>. In one implementation engagement mechanism <NUM> secures base <NUM> in a cross-table (Y-Axis) direction and a vertical direction (Z-Axis). Stated another way single engagement mechanism <NUM> secures base <NUM> in a cross-table direction parallel to a patient table plane defined the patient supporting surface <NUM> and a vertical direction perpendicular to the patient supporting surface <NUM>.

Engagement mechanism <NUM> includes a mechanism having a first cam assembly <NUM> operated by a handle <NUM> through a rack gear <NUM>. Handle <NUM> can be any actuator known in the art, such as a button, dial, gear, handle or similar devices. First cam assembly <NUM> includes a first cam surface <NUM> that acts to move base <NUM> in the cross-table (Y-axis) direction and a second cam surface <NUM> that acts to move base <NUM> in the vertical (Z-axis) direction. In one implementation engagement mechanism <NUM> includes a second cam assembly <NUM> similar to first cam assembly <NUM> and rotationally linked to first cam assembly <NUM> via rack gear <NUM>. While a rack and pinion device is one option other linkage devices can be used. Movement of handle <NUM> from a first position in which first cam assembly <NUM> and second cam assembly <NUM> are free from and not in contact with first rail <NUM> to a second position in which first cam assembly <NUM> and second cam assembly <NUM> are in direct contact with first rail <NUM>. In one implementation handle moves <NUM> degrees from the first position to the second position, though other degrees of rotation are contemplated such as <NUM> degrees or other amount of movement. It is noted that the angle of handle rotation does not need to equal the angle of the cam rotation. In one implementation the angle of cam rotation is greater than the angle of handle rotation. Referring to <FIG>, <FIG> handle <NUM> is moved in an engagement direction <NUM> to engage first engagement member <NUM> and second engagement member <NUM> with first rail <NUM> and second rail <NUM>.

Movement of handle <NUM> about pivot axis <NUM> rotates first cam assembly <NUM> and second cam assembly <NUM> through a rack gear <NUM> and pinion <NUM>. Handle <NUM> contacts a first stop <NUM> in the first position and a second stop <NUM> in the second position. As handle <NUM> moves from the handle first position to the second handle position a first region <NUM> of first cam surface <NUM> contacts outer surface <NUM> of first rail <NUM> thereby moving the support <NUM> in the cross-table direction from second rail <NUM> toward first rail <NUM>. In this manner engagement surface <NUM> of second engagement member <NUM> contacts outer surface <NUM> of second rail <NUM> and tab <NUM>. Tab <NUM> has a beveled surface <NUM> that engages opposing second rail lower surface <NUM> as support <NUM> is moved in the cross-table direction from second rail <NUM> toward first rail <NUM>.

After movement of handle <NUM> first from the first handle position to the second handle position a first beveled portion <NUM> of second cam surface <NUM> contacts first rail lower surface <NUM> of first rail <NUM> and progressively engages a second portion <NUM> of second cam surface <NUM> thereby moving support <NUM> in a downward direction along the negative z-axis. Once handle is moved to the second handle position, support <NUM> is secured to patient table <NUM>. In one implementation handle <NUM> is moved in a single motion to secure support <NUM> to patient table <NUM> in both the cross-table direction (Y-axis) and vertical direction (Z-axis). Releasing support <NUM> from patient table <NUM> is accomplished by moving handle <NUM> from the second handle position to a first handle position. Note that in one implementation first cam surface <NUM> contacts first rail <NUM> before second cam surface <NUM> contacts first rail <NUM>.

A single handle <NUM> is moved to operatively engage first engagement member <NUM> and second engagement member <NUM> with first rail <NUM> and second rail <NUM> as well as engage first pad <NUM> with patient supporting surface <NUM>. Engagement mechanism <NUM> by use of a single actuator <NUM> moving in a single direction about pivot axis <NUM> operatively engages and disengages support <NUM> from patient table <NUM>.

Referring to <FIG>, as handle <NUM> moves from the first handle position to a position intermediate the first handle position and the second handle position support <NUM> is first moved in the cross-table direction (-Y axis direction) and then second cam surface engages first rail lower surface <NUM> thereby moving support <NUM> in a downward (-Z axis) direction.

Referring to <FIG> first pad <NUM> is biased with a biasing member <NUM> such that a pad force is applied to patient supporting surface <NUM> when support <NUM> is in the secured position. In one implementation first pad <NUM> is pivotally attached to base <NUM> with a pad arm <NUM>. Biasing member <NUM> includes a compression spring and in one implementation includes two compression springs having a substantially constant spring force over the range of deflection when support <NUM> is secured to patient table <NUM>. First pad <NUM> is positioned on pad arm <NUM> away from biasing member <NUM>. The pad Force provides resistance to vertical, pitch, roll forces. In one implementation first pad <NUM> contacts patient supporting surface <NUM> proximate first rail <NUM>. In the preload position in which support <NUM> is not in contact with patient supporting surface <NUM> biasing member <NUM> biases first pad <NUM> away from base <NUM> in a downward direction away from a bottom surface <NUM> of base <NUM> such that bottom surface <NUM> is intermediate a top surface <NUM> and the free surface of first pad <NUM>. As support is moved from the loading position to a secured position a pad force is applied to patient supporting surface <NUM> from first pad <NUM>. In one implantation there is sufficient travel in the biased pad suspension that when pad arm <NUM> is loaded the spring has not bottomed out. Pad arm <NUM> includes a hard stop that limits the travel of <NUM> toward patient supporting surface <NUM>. This hard stop in the biased pad suspension allows for a lower spring constant such that one does not have to put a lot of energy into getting it to load each time support <NUM> is installed. In one implementation biasing member <NUM> applies <NUM>% of the weight of the robotic drive <NUM> and support <NUM>. So, where the weight of the robotic drive <NUM> and support <NUM> is <NUM> the biasing member applies a force countering <NUM>% of the force applied by the <NUM>.

A second pad <NUM> is positioned on base <NUM> distal to first pad <NUM> and contacts patient supporting surface <NUM> closer to second rail <NUM> than first rail <NUM>. Second pad <NUM> reacts to roll moments depending on the location of the center of mass of the support and robotic drive.

Referring to <FIG> in one implementation a distal end of robotic drive <NUM> can be moved within a zone <NUM> along the cross-table (Y-axis) and longitudinal table direction (X-axis) by movement of the positioning system <NUM>. In one embodiment the movement of positioning system <NUM> is limited such that the distal end of robotic drive <NUM> remains within zone <NUM>. In one implementation the movement of the distal end of robotic drive <NUM> is accomplished by limiting the movement of the articulated arm portion of the positioning system. The corresponding center of mass of the support <NUM> including the base and articulated arm is identified on <FIG> as center of mass zone <NUM>. In one implementation the center of mass of the support <NUM> and robotic drive <NUM> may be laterally displaced from first rail <NUM> in a direction away from second rail <NUM>. Stated another way the center of mass in one position when the distal end of robotic drive <NUM> is within zone <NUM> in the X-Y plane is off of patient table <NUM>. The force applied by the mass of the support and robotic drive <NUM> applies a vertical force to patient supporting surface <NUM>, first rail <NUM> and second rail <NUM>.

The biasing force of biasing member <NUM> is selected such that the force of the support and robotic drive <NUM> combined with the pad force does not exceed a predetermined limit force on the first rail <NUM>, second rail <NUM> and patient supporting surface <NUM>. Stated another when the force applied to first rail <NUM> and second rail <NUM> would exceed a preterminal limit (orthogonal, pitch and/or roll) from the weight of robotic drive <NUM> and support <NUM> the pad force offsets the applied forces so that the predetermined force limit on the rails and patient support surface is not exceeded. Note that the force applied to first rail <NUM> by robotic drive <NUM> and support <NUM> depends on the orientation of the articulated arm. As noted herein the center of mass of the robotic drive <NUM> and support <NUM> has a limited locational range or mass zone <NUM> during a procedure. For all locations of the center of mass within mass zone <NUM> the pad force ensures that the predetermined force limit is not exceeded. Note that mass zone <NUM> may be larger than illustrated and may also cover the locations of support <NUM> during loading of support <NUM> to the patient table and during the application of draping to support <NUM>. Referring to <FIG> a schematic sketch of a portion of patient table <NUM> shows the locations of forces F1- F7 acting on patient supporting surface <NUM>, first rail <NUM> and second rail <NUM>. Note that there are the locations that forces act on first rail <NUM> are spaced in the longitudinal X axis direction namely the locations that first cam assembly <NUM> and second cam assembly <NUM> contact first rail <NUM> as well as the two locations in which the ledge of each cam assembly contacts first rail <NUM>. In one implementation each ledge is positioned along the longitudinal axis at generally the same location as the first cam assembly and second cam assembly. While the force applied to the second rail <NUM> is at the location in which tab <NUM> contacts second rail <NUM>.

Depending on the location of the center of mass of the combined robotic drive and support, a force may be transmitted to first rail upper surface <NUM> via ledge <NUM>. In one implementation ledge <NUM> is closely positioned adjacent but does not contact first rail upper surface <NUM>. However, the center of mass of the robotic drive and support may be positioned such that ledge <NUM> will contact first rail upper surface <NUM> and transmit a force to first rail upper surface <NUM>.

Referring to <FIG> and <FIG> imaging system <NUM> includes an x-ray source <NUM> and a detector <NUM> both of which are supported on a C-arm. In one implementation support <NUM> is positioned on the table at indicia <NUM> such that the further position that distal end <NUM> of robotic drive <NUM> does not contact detector <NUM>. In one implementation a sensor tracks the location of robotic drive relative to the imaging system and provides an alert to a user when a collision between robotic drive <NUM> and the imaging system is about to occur. Stated another way an alert in the form of audio signal or a display when the robotic drive <NUM> is within a predetermined distance of the imaging system. In one implementation the distal end <NUM> of robotic drive <NUM> has a tapered contour such that a height <NUM> of the tapered portion is less than the height <NUM> of the nontapered portion of robotic drive <NUM>. In one implementation movement of distal end <NUM> of robotic drive <NUM> within zone <NUM> will provide a clearance <NUM> in a vertical direction (Z axis) and a clearance <NUM> in the longitudinal table direction.

Referring to <FIG> in one implementation a support <NUM> includes an engagement mechanism <NUM> that releasably moves a first paddle <NUM> and a second paddle <NUM> toward and away from outer surface <NUM> of first rail <NUM>. Engagement mechanism <NUM> includes a first roller cam <NUM> and a second roller cam <NUM> that releasably contact the lower surface <NUM> of first rail <NUM>. While engagement mechanism <NUM> and engagement mechanism <NUM> both operate to provide cross-table and vertical motion to support <NUM> and support <NUM> respectively, as discussed herein engagement mechanism <NUM> includes a first roller cam <NUM> and a second roller cam <NUM> instead of the sliding cam surfaces <NUM>. First roller cam <NUM> and second roller cam <NUM> rotate about their longitudinal axis as first roller cam <NUM> and second roller cam <NUM> engage first rail <NUM>.

Engagement mechanism <NUM> includes a handle <NUM> that actuates first paddle <NUM> and first roller cam <NUM> by a first linkage <NUM>. Handle <NUM> actuates second paddle <NUM> and second roller cam <NUM> by a second linkage <NUM>. First linkage <NUM> includes a first linkage member <NUM> pivotally connected to first member <NUM>. Second linkage <NUM> includes a linkage member <NUM> operatively connected to handle <NUM> and a second linkage <NUM>. A third linkage <NUM> is pivotally connected to second linkage <NUM> and a second member similar to first member <NUM>. Second linkage <NUM> includes two more linkage members than first linkage <NUM> in order to change the direction in second paddle <NUM> and second roller cam <NUM> engage first rail <NUM> as discussed herein.

Referring to <FIG> and <FIG> handle <NUM> is in a first disengaged position. In the first disengaged position, first paddle <NUM>, first roller cam <NUM>, second paddle <NUM>, and second roller cam <NUM> are in a first position. As a user moves handle <NUM> clockwise about a pivot, first linkage <NUM> operatively moves first paddle <NUM> in a first direction <NUM> direction about a first paddle post into contact with outer surface <NUM> of first rail <NUM> at a first location. Simultaneously second linkage <NUM> operatively moves second paddle <NUM> in a second direction <NUM> opposite first direction <NUM> about a second paddle post into contact with outer surface <NUM> of first rail <NUM> at a second location spaced from the first location. In one implementation first direction <NUM> is clockwise and second direction <NUM> is counterclockwise. Stated another way first paddle <NUM> and second paddle <NUM> move in opposite directions along the longitudinal axis of first rail <NUM> as handle <NUM> is moved from the disengaged position to the engaged position. Similarly, first roller cam <NUM> and second roller cam <NUM> also move in opposite directions along the longitudinal axis of first rail <NUM> as handle <NUM> is moved from the disengaged position to the engaged position. This opposite movement minimizes the chance that support <NUM> will inadvertently move along the longitudinal ais of first rail <NUM> as handle <NUM> is moved from the disengaged to engaged positions.

Referring to <FIG> first linkage <NUM> includes a first member <NUM> that pivots about a post or cam shaft <NUM> having a longitudinal axis <NUM>. First member includes an extension fixedly rotatingly supporting second roller cam <NUM>. First member also includes a post having a longitudinal axis parallel to longitudinal axis <NUM> about which a first guide roller <NUM> rotates. First guide roller <NUM> engages outer surface 214a of first paddle <NUM>. Outer surface 214a of first paddle <NUM> includes a number of regions with different profiles, A first profile 214b, a second profile 214c and a third profile 214d. Additionally there are transition regions between each of the profiles. In the disengaged position first guide roller <NUM> is engaged with first profile 214b. First paddle <NUM> is spring biased against first guide roller <NUM> by a biasing member such as a spring to bias paddle toward roller <NUM> about paddle post <NUM>. As handle <NUM> is moved by a user from the disengaged position toward the engaged position first guide roller <NUM> moves from first profile 214b toward second profile 214c over the transition between first profile 214b and second profile 214c and thereby moves first paddle <NUM> toward first rail <NUM>. As handle <NUM> is moved to the fully engaged position first guide roller <NUM> moves from second profile second profile 214c to third profile 214d. The second profile maintains the paddle in the same location despite the cam moving. This allows the vertical shift to happen with no change in horizontal movement. Third profile 214d is a dwell profile is configured such that the force between first paddle <NUM> and first guide roller <NUM> does not move first guide roller <NUM> back toward the paddle post. Stated another way in the third profile there is no net torque on the camshaft.

Referring to <FIG>, <FIG> as handle <NUM> is moved from the fully disengaged position to the fully engaged position first roller cam <NUM> is moved from a position in which roller cam <NUM> is not in contact with first rail lower surface <NUM> to a position in which first roller cam <NUM> is in contact with first rail lower surface <NUM>. First roller cam <NUM> includes a first frustoconical portion 218a and a second conical portion 218b as handle <NUM> is moved from the fully disengaged position to the fully engaged position first frustoconical portion 218a of first roller cam <NUM> first contacts first rail lower surface <NUM>. First roller cam <NUM> rotates about the first roller cam <NUM> longitudinal axis as first roller cam <NUM> contacts first rail lower surface <NUM>. In the fully engaged position second conical portion 218b of first roller cam <NUM> is in contact with first rail lower surface <NUM> thereby securing support <NUM> to patient supporting surface <NUM>.

Support <NUM> includes an engagement member <NUM> having a first substantially planar portion 232a, a second sloped surface 232b extending between first substantially planar portion 232a and a third planar portion 232c. When a user places support <NUM> over patient supporting surface <NUM> first substantially planar portion 232a rests on first rail upper surface <NUM> of first rail <NUM>. As first paddle <NUM> is moved toward first rail <NUM> by actuation of handle <NUM> first rail upper surface <NUM> moves from first substantially planar portion 232a to second sloped surface 232b and ultimately third planar portion 232c when handle <NUM> is in the fully engaged position.

Similar to support <NUM>, support <NUM> includes a cross-arm and a second engagement member to engage second rail <NUM>. Second engagement member includes a tab <NUM> having an upper beveled surface 230a that guides opposing second rail lower surface <NUM> to an upper planar surface 230b of tab <NUM>. In certain situations, in which the center of gravity of support <NUM> would cause an outer edge of opposing second rail lower surface <NUM> to otherwise hit tab <NUM> as support <NUM> is being loaded onto patient supporting surface <NUM>.

Claim 1:
A support (<NUM>, <NUM>) for attaching a mechanism, in particular a positioning system (<NUM>) and/or a robotic drive (<NUM>), to a patient table, the patient table having a patient supporting surface (<NUM>) and a first rail (<NUM>) and a second rail (<NUM>), the support (<NUM>, <NUM>) comprising:
a base (<NUM>) comprising;
a first engagement member (<NUM>);
a second engagement member (<NUM>); and
a single engagement mechanism (<NUM>, <NUM>),
characterized in that the single engagement mechanism (<NUM>, <NUM>, <NUM>, <NUM>) is moving the first engagement member (<NUM>) and the second engagement member (<NUM>) from a loading position to a secured position securing the base (<NUM>) to the first rail (<NUM>) and the second rail (<NUM>).