User-controllable power-assisted system and method for the application of pressure

A system and a method for a controllable power-assisted application of pressure includes a force sensor capable of sensing a user-applied force; and a force generator responsive to the sensed user-applied force and capable of generating a force that is applied to a pressure-applying device. A force magnitude of the force applied to the pressure-applying device is based on a magnitude of the sensed user-applied force. One embodiment provides that the force applied to the pressure-applying device by the force generator exerts a predetermined amount of pressure against a surface. Another embodiment provides that the force magnitude is greater than a magnitude of the sensed user-applied force. Yet another embodiment provides that the force magnitude is proportional to a magnitude of the sensed user-applied force.

BACKGROUND

The subject matter disclosed herein relates to a system and method for a power-assisted application of pressure. More particularly, the subject matter disclosed herein relates to a system and a method for a controllable power-assisted application of pressure.

DETAILED DESCRIPTION

The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not to be construed as necessarily preferred or advantageous over other embodiments. The words “transducer” and “transducer head” are used herein to mean “a device that is actuated by power and/or energy from one system and supplies power and/or energy usually in another form to a second system.” Additionally, it should be understood that the words “transducer” and “transducer head” include bidirectional transducer devices.

The subject matter disclosed herein relates to a controllable power-assisted system and method for the application of pressure. In one exemplary embodiment, the subject matter disclosed herein provides a controllable power-assisted sonographic system (also commonly known as an ultrasound system) that allows an operator (or user), such as a physician or a sonogram technician, to apply about 50 pounds of pressure to a selected area of a prone patient in response to a hand-guided force of about 2-8 pounds of pressure. In another exemplary embodiment, the subject matter disclosed herein allows an operator to apply between about 0-8 pounds of pressure through a sonographic transducer head or a sonogram transducer head coupling device, which is assisted by the subject matter disclosed herein to deliver between about 0 pounds of pressure to a maximum of about 40 pounds of pressure, as guided by the operator.

FIG. 1depicts a functional block diagram of one exemplary embodiment of a system100for providing a controllable power-assisted application of pressure according to the subject matter disclosed herein. System100includes sonographic processing equipment101and a controllable, power-assist device102. Controllable power-assist device102generates a controllable force in a near vertical direction115that can be used for applying a pressure-applying device, such as a transducer head, against soft tissue of a prone patient, a portion of which is indicated at120, with a desired level of uniform and sustained pressure.

Sonographic processing equipment101includes a processor103and a pressure-applying device104, which is coupled to processor103in a well-known manner through a cable or wire105. Alternatively, pressure-applying device104could be coupled to processor103in a well-known manner using a wireless link. For many of the exemplary embodiments of the subject matter disclosed herein, pressure-applying device104comprises a sonographic (ultrasound) transducer head and will be described as such. It should be understood, though, that pressure-applying device104is not limited to being a sonographic transducer head and could alternatively be a transducer head, a radiographic transducer head, an x-ray head, a sterilizing transducer head, an instrumentation head and/or a device used for penetrating soft materials and/or tissue.

Processor103can include the necessary components and/or algorithms for processing sonographic signals received by transducer head104and the necessary components for displaying sonographic information and/or outputting sonographic information to another processing device. Each of processor103, transducer head104and cable105can be readily available sonographic devices and/or components. Alternatively, any one of processor103, transducer head104and cable105could be adapted for a special sonographic application.

Power-assist device102includes a force generator106, a power-assist arm107, a coupling member108, a coupling member109, a coupling device110, and an operator-applied-force sensor111for controlling the power-assisted force generated by power-assist device102. In one exemplary embodiment, coupling device110is coupled to power-assist arm107and coupling member108without using coupling member109. In another exemplary embodiment, coupling device110is coupled directly to force generator106. In yet another exemplary embodiment, pressure-applying device104is coupled directly to force generator106. Power-assist arm107is depicted inFIG. 1as a four-bar parallelogram-linkage-type power assist arm that operates in a well-known manner to impart a controlled force to coupling device110. Alternatively, power-assist arm107can be configured as a single-bar-type power assist arm.

In one exemplary embodiment, force generator106is a controllable pneumatic force generator that operates in a well-known manner for generating a force that is coupled in a well-known manner to power-assist arm107and through power-assist arm107, coupling arm108, and coupling member109to coupling device110. In another exemplary embodiment, force generator106could be a controllable hydraulic force generator that operates in a well-known manner for generating a force that is coupled in a well-known manner to power-assist arm107and through power assist arm107, coupling arm108and coupling member109to coupling device110. In still another exemplary embodiment, force generator106could be a controllable electric servo motor or stepper motor that operates in a well-known manner for generating a force that is coupled in a well-known manner to power-assist arm107and through power assist arm107, coupling arm108and coupling member109to coupling device110. In one exemplary embodiment, force generator106includes a controller, such as a state machine formed from, for example, discrete logic, that controls the functional operation of force generator106by responding to sensor111, as described below, and for providing safety features. In another exemplary embodiment, force generator106includes a programmable controller, such as a programmable microcontroller or programmable microprocessor, that controls the functional operation of force generator106by responding to sensor111, as described below, and for providing safety features.

Operator-applied-force sensor111senses a force that an operator applies to pressure-applying device104as the operator hand-guides pressure-applying device104and generates a signal corresponding to the sensed force. In one exemplary embodiment, sensor111is embodied as a pressure-sensitive switch that senses the amount of pressure an operator places on sensor111as the operator hand-guides transducer head104toward patient120or a desired target. Alternatively, sensor111could be configured to sense the pressure created between coupling device110and transducer head104when the operator hand-guides transducer head104toward patient120or a desired target. As yet another alternative, sensor111could be a pressure switch that is actuated by an operator when the operator applies a predetermined amount of force or pressure to the pressure switch. Sensor111accordingly generates a signal corresponding to the amount of sensed pressure and that is coupled to force generator106in a well-known manner, such as, but not limited to, a wired connection or a wireless connection. In response to the signal generated by sensor111, force generator106generates a force that is applied to power-assist arm107, thereby lowering transducer head104toward patient120or a desired target, thereby assisting the hand-guided motion the operator is applying to transducer head104. In one exemplary embodiment, when an operator applies pressure to either transducer head104or directly to a sensor111, force generator106is responsive to the magnitude of pressure sensed by sensor111and generates a force that is related to and greater than the magnitude of the pressure sensed by sensor111. In one embodiment, the force generated by force generator106is proportional to the magnitude of the pressure sensed by sensor111. When transducer head104comes into contact with patient120or a desired target, force generator106generates a force that is applied to transducer104through power-assist arm107so that transducer104contacts the patient with sufficient uniform and sustained pressure to produce a sonographic image with sonographic processing equipment101. That is, force generator106amplifies the force sensed by sensor111to a predetermined amount to produce a sonographic image with sonographic processing equipment101.

In one exemplary embodiment, force generator106generates about 0 pound of pressure to a maximum of about 40 pounds of pressure in response to a sensed pressure of between about 0-8 pounds of pressure. In another exemplary embodiment, force generator106generates about a 50 pounds of pressure through power-assist arm107to a selected area of prone patient120in response to a hand-guided force of about 2-8 pounds of pressure. In yet other exemplary embodiments, force generator106can be configured to generate a selected amplified minimum and maximum force in response to a selected range of pressure sensed by sensor111.

Coupling device110provides a mechanical coupling between pressure-applied device104, power-assist arm107, coupling member108and coupling member109(when included). In one exemplary embodiment, coupling device110could be provided by screw-band-type hose clamps having a sufficient diameter for operatively receiving transducer head104. In another exemplary embodiment, coupling device110could releasably hold a transducer head104so that the transducer head could be used coupled to power-assist arm107or in a free-hand manner depending on the specific procedure being performed. In yet another exemplary embodiment, a second transducer head104(not shown inFIG. 1) could be simultaneously coupled to processor103of sonographic processing equipment101through a cable (also not shown).

In one exemplary embodiment, power-assist arm107includes a section that allows transducer head104(i.e., pressure-applying device104) to be oriented horizontally so that a side sonographic image of a patient can be produced. For this exemplary embodiment, when transducer head104is horizontally oriented, sensors, such as position sensors and/or contact sensors (not shown inFIG. 1), sense the orientation of transducer head104and disengage force generator106so that power-assist arm107can be freely positioned around a patient and so that force generator106does not generate a force. In one exemplary embodiment, the position sensors and/or contact sensors sense the position of transducer head104when transducer head104is rotated past about 20-30 degrees from vertical orientation and disengage force generator106. In another exemplary embodiment, when the sensors sense that transducer head104is rotated past about 20-30 degrees from vertical orientation, force generator106is controlled to reduce the force generated, for example, in proportion to the amount of sensed rotation from a predetermined orientation, such as vertical, or as a sinusoidal-based decay function based on the amount of sensed rotation from a predetermined orientation.

Power-assist device102is depicted inFIG. 1as being fastened to a fixed structure112, such as a wall or a pole.FIG. 2depicts a functional block diagram of an alternative exemplary embodiment of a system200that is part of a mobile device220, such as a cart, and that can be positioned where desired for performing a controllable power-assisted application of pressure according to the subject matter disclosed herein. System200is configured similar to system100, shown inFIG. 1, and includes sonographic processing equipment201and a controllable, power-assist device202. Controllable power-assist device202generates a controllable force in a near vertical direction215that can be used for applying a transducer head against soft tissue of a prone patient (not shown inFIG. 2).

FIG. 2depicts sonographic processing equipment201includes a processor203and pressure-applying device204, such as a sonographic head, which is coupled to processor203in a well-known manner through a cable or wire205. Alternatively, pressure-applying device204could be coupled to processor203in a well-known manner using a wireless link. For this and many of the exemplary embodiments of the subject matter disclosed herein, pressure-applying device204comprises a sonographic (ultrasound) transducer head and will be described as such. It should be understood, though, that pressure-applying device204is not limited to being a sonographic transducer head and could alternatively be a transducer head, a radiographic transducer head, an x-ray head, a sterilizing transducer head, an instrumentation head and/or a device used for penetrating soft materials and/or tissue. Processor203can include the necessary components and/or algorithms for processing sonographic signals received by transducer head204and the necessary components for displaying sonographic information and/or outputting sonographic information to another processing device.

Power-assist device202includes a force generator206, a power-assist arm207, a coupling member208, a coupling member209, a coupling device210, and an operator-applied-force sensor211for controlling the power-assisted force generated by power-assist device202. In one exemplary embodiment, coupling device210is coupled to power-assist arm207and coupling member208without using coupling member209. In another exemplary embodiment, coupling device210is coupled directly to force generator206. In yet another exemplary embodiment, pressure-applying device204is coupled directly to force generator206. Power-assist arm207is depicted inFIG. 2as a four-bar parallelogram-linkage-type power assist arm that operates in a well-known manner to impart a controlled force to coupling device210. Alternatively, power-assist arm207can be configured as a single-bar-type power assist arm. Mobile cart220includes a mounting member221to which system200is mounted in a well-known manner.

Operator-applied-force sensor211senses a force that an operator applies to pressure-applying device204as the operator hand-guides pressure-applying device204and generates a signal corresponding to the sensed force. In one exemplary embodiment, sensor211is embodied as a pressure-sensitive switch that senses the amount of pressure an operator places on sensor211as the operator hand-guides transducer head204toward a patient or a desired target. Alternatively, sensor211could be configured to sense the pressure created between coupling device210and transducer head204when the operator hand-guides transducer head204toward a patient or a desired target. As yet another alternative, sensor211could be a pressure switch that is actuated by an operator when the operator applies a predetermined amount of force or pressure to the pressure switch. Sensor211accordingly generates a signal corresponding to the amount of sensed pressure and that is coupled to force generator206in a well-known manner, such as, but not limited to, a wired connection or a wireless connection. In response to the signal generated by sensor211, force generator206generates a force that is applied to power-assist arm207, thereby lowering transducer head204toward a patient or a desired target, thereby assisting the hand-guided motion the operator is applying to transducer head204. In one exemplary embodiment, when an operator applies pressure to either transducer head204or directly to a sensor211, force generator206is responsive to the magnitude of pressure sensed by sensor211and generates a force that is related to and greater than the magnitude of the pressure sensed by sensor211. In one embodiment, the force generated by force generator206is proportional to the magnitude of the pressure sensed by sensor211. When transducer head204comes into contact with a patient or a desired target, force generator206generates a force that is applied to transducer204through power-assist arm207so that transducer204contacts the patient or the desired target with sufficient uniform and sustained pressure to produce a sonographic image with sonographic processing equipment201. That is, force generator206amplifies the force sensed by sensor211to a predetermined amount to produce a sonographic image with sonographic processing equipment201.

FIG. 3depicts a functional block diagram of another exemplary embodiment of a system300for providing a controllable power-assisted application of pressure that can be positioned to, for example, a desired horizontal position within a selected area that is, for example, about two square feet and also provides, for example, about a30inch vertical travel315for transducer head304according to the subject matter disclosed herein. System300includes sonographic processing equipment301and a controllable, power-assist device302. Controllable power-assist device302generates a controllable force that can be used for applying a transducer head against soft tissue of a prone patient120.

Sonographic processing equipment301includes a processor303and pressure-applying device304, which is coupled to processor303in a well-known manner through a cable or wire305. Alternatively, transducer head304could be coupled to processor303in a well-known manner using a wireless link. For this and many of the exemplary embodiments of the subject matter disclosed herein, pressure-applying device304comprises a sonographic (ultrasound) transducer head and will be described as such. It should be understood, though, that pressure-applying device304is not limited to being a sonographic transducer head and could alternatively be a transducer head, a radiographic transducer head, an x-ray head, a sterilizing transducer head, an instrumentation head and/or a device used for penetrating soft materials and/or tissue. Processor303can include the necessary components and/or algorithms for processing sonographic signals received by transducer head304and the necessary components for displaying sonographic information and/or outputting sonographic information to another processing device. Each of processor303, transducer head304and cable305can be readily available sonographic devices and/or components. In another alternative embodiment, any one of processor303, transducer head304and cable305could be adapted for a special sonographic application.

Power-assist device302includes a force generator306, a power-assist arm307, a coupling member308, a coupling member309, a coupling device310, and an operator-applied-force sensor311for controlling the power-assisted force generated by power-assist device302. In one exemplary embodiment, coupling device310is coupled to power-assist arm307and coupling member308without using coupling member309. Power-assist arm307comprises a four-bar parallelogram-linkage-type arm portion307athat is operatively coupled to rotary-type joint307b,207cthat is operatively coupled to single-bar-type arm307d, which in turn is operatively coupled to coupling member308. Rotary-type joint307b,307coperates in a well-known manner to allow joint portion307cto rotate with respect to joint portion307b. Power-assist arm307operates in a well-known manner to impart a controlled force to coupling device310. Alternatively, power-assist arm307could be configured so that four-bar parallelogram-linkage arm portion307aand single-bar arm portion307dare interchanged. As yet another alternative, power assist arm307could have two or more four-bar parallelogram-linkage arm portions307aand/or two or more single-bar arm portions307d. Operator-applied-force sensor311operates in a manner similar to operator-applied-force sensors111and211.

Power-assist device302is depicted inFIG. 3as being fastened to a fixed structure312, such as a wall or a pole. Alternatively, power-assist device302could be mounted on a mobile device, such as a cart, similar to that depicted inFIG. 2.

The subject matter disclosed herein further includes safety features that limit the pressure applied to a patient in a well-known manner, such as by pressure sensors that detect the pressure being applied to a patient and/or by pressure sensors that can determined the amount of pressure being applied to a patient based on the amount of pressure developed by force generator106. Additional safety features that can be included with the subject matter disclosed herein include a release mechanism that allows, for example, power-assist arm107to be released and moved away from a patient when, for example, pressure sensors detect the pressure being applied to a patient to exceed a predetermined pressure level.

One exemplary embodiment of the subject matter disclosed herein provides a transducer-coupling device having a gripping surface of about 1.25″ diameter that may includes a pressure-sensitive switch. For this exemplary embodiment, an operator must actuate and hold the switch in order for the force generator and arm brakes to be active in a well-known manner. When the pressure-sensitive switch in not actuated, the power-assist arm floats free, thereby allowing a plurality of modes of operation.

According to yet another exemplary embodiment of the subject matter disclosed herein, an operator positions the transducer head on a selected location on the body of a patient and orients the transducer head at a desired “target”. The operator then activates the power-assist device portion of the system by applying pressure to the pressure-sensitive switch and simply pushing the transducer head toward the target, thereby causing the power-assist arm to push the transducer head further into the body of the patient. For this exemplary embodiment, the power-assist device portion is gimbaled and allows about 5 degrees of pivot in any direction, thereby allowing an operator a small amount of side to side movement in order to get a better view of the target. To allow more travel in any the x, y or z directions, the operator releases the pressure-sensitive switch, which, in turn, releases the arm brake and the force generator, thereby allowing the whole assembly to be repositioned. In still another exemplary embodiment of the present invention, the power-assist portion of the system provides x, y and z axes directions of travel while applying pressure to a patient.

One exemplary application of the subject matter disclosed herein is in a semi-clean environment such as a physician's, a hospital or clinic-type examination room. Another exemplary application of the subject matter disclosed herein is in a semi-clean environment such a veterinary large-animal examination facility. Yet another exemplary application for which the subject matter disclosed herein could be used is for applying an inspection device to a soft material or tissue, such as meat. The subject matter disclosed herein is also suitable for providing hand-guided uniform and sustained pressure for a radiographic application, an x-ray, a sterilization application and/or an instrumentation application. Still another exemplary application for which the subject matter disclosed herein could be used is for applying a force to a penetrating device in order to penetrate a material or target with a predetermined amount of force or pressure. For any of the exemplary applications for which the subject matter disclosed herein may be used, the subject matter disclosed herein could be configured so that the power-assisted application of pressure could be in a horizontal direction depending upon the specific application. Alternatively, the subject matter disclosed herein could be configured so that the power-assisted application of pressure could be in a direction that is substantially the same direction in which the operator-applied force is applied.

Although the foregoing disclosed subject matter has been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practiced that are within the scope of the appended claims. Accordingly, the present embodiments are to be considered as illustrative and not restrictive, and the subject matter disclosed herein is not to be limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.