Abstract: Fluid delivery device, allowing a mechanical robot arm to be supplied with fluids from at least two sources of fluids, includes a fixed portion or stator, having connections to the sources of fluids, and a rotating portion or rotor, capable of moving with the robot arm, and comprising a plurality of connections for a link with the said robot arm. A first series of channels run through a central portion of the rotor sealing at a passage between the rotor and the stator is provided by seals. A second series of channels run through a peripheral portion of the rotor. Continuity between portions of these channels situated respectively on the rotor and the stator is provided in a zone without contact, with a reduced mechanical clearance.

Abstract: A robot apparatus and a motion controlling method for the robot apparatus wherein a reflex motion or the like can be performed at a high speed while decreasing the calculation amount of and the concentrated calculation load to a control apparatus. The robot has a control configuration having a hierarchical structure including a higher order central calculation section corresponding to the brain, reflex system control sections corresponding to the vertebra, and servo control systems and actuators corresponding to the muscles. From restrictions to the power consumption and so forth, there is a limitation to increase of the speed of a control cycle of the higher order central calculation section. External force acting upon the machine body is a disturbance input of a high frequency band, and a very high speed control system is required.

Abstract: A robot system includes a plurality of segments 3, joints 4 for linking the segments together, drive units 5 for actuating the joints, and a controller 8 for controlling the drive units. Further, the robot system has bladders 2 filled with a fluid being of lower specific gravity than the outside environment. A center of buoyancy differs from a center of gravity, and the robot system has a specific gravity of greater than 1 relative the outside environment.

Abstract: A robot is obtained having various functions that are demanded for planetary landing vehicles, extreme operations robots or the like, in particular to provide a leg structure for a robot that is capable of getting up itself when overturned, facilitating take-off and landing on uneven ground, and that has a walking function and that has a hand function capable of three-dimensional operation. A robot comprises a main robot body and at least three legs mounted on this main body for enabling three-dimensional movement of the main robot body such as a self-erecting action or walking action; each leg is constituted by a multi-joint arm having a plurality of said offset rotary joints linked together and has a ground-engaging member mounted at the leading end of the arm, so that each leg is capable of independently controlled three-dimensional movement and drive.

Abstract: A robot apparatus is provided which includes body portions such as a head block (4), leg blocks (3A to 3D), an actuator (25) to actuate the body portions and a CPU (10) to supply a control signal to the actuator (25). In this apparatus, information about an external force applied to the apparatus, such as the position, magnitude, direction, etc. of the external force, is computed on the basis of changes of the control signal supplied from the CPU (10) to drive the actuator (25) and a signal supplied as a response to the CPU (10) when the actuator (25) is driven. The external force information is supplied to the CPU (10) and used as information for selection of a behavior and emotion of the robot apparatus and the next behavior of the apparatus.

Abstract: A cable array robotic system and apparatus for applications such as cargo handling at sea and pallet handling in manufacturing, based on a multi-cable robotic control system is disclosed. The cables are deployed from three or more folding, telescoping masts at the corners of a work area. The cables attach to an end-effector (e.g. a spreader mechanism) that grips an object (e.g. a container) and affects desired movements as directed by an operator through a computer controlled graphical user interface using pointing directives such as “put that there”. Various sensors and cameras enable a high degree of control over the end-effector (e.g. spreader or pallet) as it is moved from place to place. Sufficient control is possible so that the present cargo handling system may unload, without pendulation, the deck and hold of a ship onto a sea-going lighter during sea state three conditions in a container handling application at sea.

Abstract: A robot system includes a plurality of segments 3, joints 4 for linking the segments together, drive units 5 for actuating the joints, and a controller 8 for controlling the drive units. Further, the robot system has bladders 2 filled with a fluid being of lower specific gravity than the outside environment. A center of buoyancy differs from a center of gravity, and the robot system has a specific gravity of greater than 1 relative to the outside environment.

Abstract: The invention provides an apparatus and method for performing surgery on a patient. The surgical apparatus includes an input device, at least one hydraulic amplifier operably attached to the input device, and an actuator operably attached to the hydraulic amplifier. Input to the input device is hydraulically modulated via the hydraulic amplifier to manipulate the actuator. The surgical method includes receiving a mechanical input for an action. The mechanical input is hydraulically modulated. The action is controlled based on the hydraulically modulated input.

Abstract: Artificial muscle analog 1000 is located within hollow exoskeletal bone 10. Muscle 1000 comprises inflatable bladder 120, cable 130, roller 140, anchor point 150, and connection means 160 whereby said bladder may be inflated and deflated. Bladder 120 is affixed to the interior surface of said bone. Cable 130, attached to bone 10 at point 150, passes over bladder 120 and through roller 140. Cable 130, if unobstructed and taut, takes a shortest path from point 150 to roller 140. When inflated, bladder 120 forces cable 130 to deviate from this shortest path, pulling cable 130 in through said roller, under tension. In their paired opposing muscle form 2000, the artificial muscles synergistically assist each other when used in opposition. Paired muscles 2000 may actuate a robotic arm 3000, and are easily controlled by the associated simple low-cost control systems 100a,b,c of the present invention.

Abstract: A robot system having a plurality of component units. The robot system includes a first storage device, and a second storage device. The robot system further includes a plurality of control devices, with a first component control device provided with the first component unit and a second component control device provided with the second component unit. The first component control device controls the first component unit and the second component control device controls the second component unit.

Abstract: A method of teaching a robot off-line having a traveling axis, by which the final position and final posture are determined when a robot having a traveling axis stops at an arbitrary position on a traveling axis. The method is able to take an arbitrary posture at the arbitrary position, change from the arbitrary position and arbitrary posture, and move a control point of the robot until it agrees with a movement target point. This position on the traveling axis of the robot is determined so as to minimize the distance between a coordinate origin of the robot a movement target point.

Abstract: The invention relates to an endoscope shaft comprising a movable distal end portion and an operating device which is operatively connected through the endoscope shaft with the distal end portion for the operation thereof. The distal end portion comprises a plurality of longitudinally stacked swelling bodies, two of which at a time are located diametrically with respect to each other and form a layer and two longitudinally directly adjacent pairs of bodies of which at a time are phase-shifted by 90°.

Abstract: A tripod bearing device featuring a stationary frame and a carrier moveable relative to it, which are connected together via three braces that are adjustable in their lengths. Each brace is coupled to the frame and to the carrier via a joint each with two rotational degrees of freedom. Moreover, a torsion drive is assigned to each brace for twisting the carrier-end joint of the relevant brace relative to the frame-end joint of this brace about its longitudinal axis. Consequently, a constructively simple parallel structure with three machining axes can be realized which, with its high dynamic stiffness, enables an accurate positioning of the carrier. Furthermore, a method for torsion compensation in the braces is given.

Abstract: New artificial muscles and actuators, that are operated by hydrogen gas as working fluid stored interstitially in metal hydrides as a hydrogen sponge. These artificial muscles and actuators are operated both electrically and thermally. The artificial muscles and actuators have fast response, are compact/light-weight, are noiseless, and produce high-power density. They can be used for biomedical, space, defense, micro-machines, and industrial applications.

Abstract: A parallel mechanism is capable of positioning and orienting an end platform with up to six or more degrees of freedom. In preferred embodiments, the mechanism includes six links having a first and second ends. The first end is connected to an end platform for supporting a tool, while the second end is connected to an actuator capable of translating the second end. A rotational drive mechanism may be provided for rotating an object mounted on the end platform at varying orientations of the end platform independently of movement of the end platform as a whole. The links may be curved in order to avoid interference between adjoining links, thereby permitting an increased range of motion and improved dexterity of the mechanism.

Abstract: A robot device having a plurality of component units connected together and controller detachably mounted on one of the component units for driving and controlling each the component units in a prescribed state. The control device is easily exchangeable for another control device. The robot device may further include a storing device detachably mounted on the respective component unit for storing desired behavior type information. The storing device is readily exchangeable for another storing device having stored therein different behavior type information.

Abstract: An electronic-component mounting system, including a printed-circuit-board supporting device which positions and supports a printed circuit board, a movable table which is movable, relative to the printed-circuit-board supporting device, in at least one of an X direction and a Y direction which are perpendicular to each other and cooperate with each other to define an X-Y plane parallel to a board-support plane on which the printed circuit board is supported by the supporting device, an electronic-component supplying device which is mounted on the movable table and which includes a component-supply portion from which electronic components are supplied one by one, and an electronic-component mounting device which is mounted on the movable table together with the electronic-component supplying device and which receives the electronic components one by one from the component-supply portion of the supplying device and mounts at least one of the electronic components on the printed circuit board positioned and sup

Abstract: A system and related method to enable six-axis movement of a structure. The system is related to hexapods, Stewart platforms and other mechanical movement systems. It includes a plurality of moveable supportive legs coupled to a platform. For the Stewart platform version of the system, there are six supportive legs, each of which connects to a triangular platform that acts as a base.

Abstract: In known hexapodal machining centers, a movable support is supported and the individual struts are articulated on the support in one plane. For permitting a greater movability of the support, especially in the rotational degrees of freedom, and for improving the absorption of the forces, a hexapodal machining center having a stationary frame and a movable support is provided, in the case of which the six connecting struts of adjustable length are articulated on the support. Three articulation points respectively define a common plane of application so that two separate planes are defined. Also, the articulation of the struts on the frame is effected in two separate planes of application.

Abstract: A modular manipulation unit is disclosed. The unit includes a body (11) formed of three extruded, profiled elements. The elements include a base plate (15), a top element or cover (16) fixed on the base plate, and an intermediate slide (17) arranged and guided between the base plate and the top element. An interface part (13) is fixed and movable with the intermediate slide, and an actuator is connected to the said intermediate slide for movements of same and of the gripping tool carried by the said interface part.

Abstract: The present invention relates to a device for transferring a fluid from a stationary (20) to a rotating machine part (3) by means of a rotary joint (1), which optionally comprises flat radial, conical or cylindrical transition surfaces, wherein an at least partially tubular connecting rod (2) rotating with the rotating machine part (3) is provided thereon for the purpose of conveying the fluid, which rod (2) extends into the area of the rotary joint (1) and which is axially displaceable with respect to the rotary joint (1).

Abstract: A device for numerically controlled (NC) manufacturing, manipulating and measuring apparatuses has a frame structure with peripheral force introduction locations and at least one movement unit with peripheral force introduction locations. At least three adjusting devices each having a first and a second part are provided. Each adjusting device has a first and a second connecting member positioned at a spacing to the first connecting member. The first parts are connected by the first connecting members to the force introduction locations of the movement unit, wherein these force introduction locations are positioned in a first imaginary coupling plane. The first parts are connected by the second connecting members to the force introduction locations of the frame structure, wherein these force introduction locations are positioned in a first imaginary coupling plane of the frame structure. The second parts are connected by the first connecting members to the movement unit.

Abstract: A composite mechanism multi-axis machine tool includes an orthogonal coordinate feeding axis mechanism and a parallel type spatial linkage mechanism. The orthogonal coordinate feeding axis mechanism has two orthogonal platforms to provide two dimensional motion vectors. The parallel type spatial linkage mechanism has three sets of linear feeding modules engaging with a base frame for holding a main spindle which further holds a tool cutter. The parallel type spatial linkage mechanism provides one dimensional motion and two dimensional rotation for the tool cutter. A controller is provided to control and coordinate the movements of the orthogonal coordinate feeding axis mechanism and the parallel type spatial linkage mechanism.

Abstract: A system is disclosed for operating an automated refueling system, the system including: a source of vacuum; a suction cup, the suction cup being capable of mating with a hinged vehicle fuel cap cover and the suction cup having an inside which is in communication with the source of vacuum through a suction system; an extension mechanism effective to laterally extend the suction cup toward a vehicle's hinged fuel cap cover; a vacuum actuated means to swing open the hinged fuel cap cover when a pressure within the suction system approaches the pressure of the source of vacuum; and a vacuum actuated cylinder to extend a filler tube into fuel tank inlet after the hinged fuel cap door is swung open. The system of the present invention minimizes the number of electrical components that are in the vicinity of the refueling nozzle.

Abstract: A linkage arrangement supports an implement such that the implement is movable relative to a support member which is also movable relative to a structure. Movement of the implement and support member is limited by mechanical and/or mechanically operated limits. The linkage mechanism enables an increase in the ability to move and orientate the implement within a limit envelope. In a preferred form, a first linkage arm is pivotably mounted to a prime mover. At a distal end of the first linkage arm an orientation member is pivotably attached, the orientation member pivotably attached to a first limit actuating arm. The rotation of the first linkage arm causes rotation of the orientation member. The orientation member provides a base for the attachment of a further arm or implement. The first arm or implement is prevented from contacting the prime mover by the limits provided by the orientation member.

Abstract: The present invention provides a robotic dispensing apparatus comprising a gear pump operably coupled to a rotatable element positioned along the sixth axis of a multi-axis robot such that the gear pump is driven by the multi-axis robot. In one embodiment of the present invention, a sixth axis motor of the multi-axis robot drives the rotatable element and a dispense valve communicates with the gear pump for receiving and dispensing viscous material from the gear pump. Preferably, a flexible coupling interconnects the gear pump and the rotatable element and a manifold and piping system cooperate to deliver the viscous material pumped by the gear pump to the dispense valve.

Abstract: A three-axis machine control structure includes a support structure and a machine component to which a workpiece or tool can be attached. Three control arms are connected between the machine component and the support structure. Preferably, each control arm is pivotably connected to the support structure and to the machine component and includes a pair of four-bar linkages connected in series. The control arms are oriented to permit rapid movement of the machine component along any or all of the three linear axes, while restricting movement of the machine component along the rotational axes.

Abstract: A linear thruster is disclosed in which a load beam is linearly moved relative to a guide beam by fluid power. One or both of the beams are multisided in cross-section to substantially increase the linear bearing area between the beams and substantially increase the strength of the linear thruster against side forces as well as moments while permitting a substantial reduction in the volumetric space consumed by the linear thruster. The fluid power and the energy inputs to the linear thruster may all be positioned at one end of the guide beam.

Abstract: A coordinate positioning machine comprises a fixed structure including a table and a supporting frame (314), rigidly connected together. A moveable arm (310) is suspended from the frame by means of three powered telescopic struts (316), each of which is universally pivotally connected to both the arm and the frame. As a consequence the moveable arm is able to move with three rotational degrees of freedom. Movement of the arm with each of these degrees of freedom is constrained by a passive device (340), connected to the arm and the fixed structure, and which eliminates all rotational movement of the arm, while simultaneously permitting translation thereof.

Abstract: A three-axis machine is disclosed. The machine includes a machine component to which a workpiece or tool can be attached. An actuator, such as three powered extensible legs, is connected between the machine component and a support structure. Three control arms also are connected between the machine component and the support structure. Preferably, each control arm is pivotably connected to the support structure and the machine component and includes a pair of four-bar linkages connected in series. The control arms are oriented to permit rapid movement of the machine component along any or all of the three linear axes, while restricting rotational movement of the machine component along the rotational axes.

Abstract: A multi-axis machine is disclosed. The machine includes an adjustable external framework having a pair of support structures connected by a plurality of servostruts. A multi-axis manipulator is attached to one support structure and may be designed to carry a tool. A workpiece may be attached to the other support structure for interaction with the tool as the tool is moved by the multi-axis manipulator. The controlled extension and retraction of both the framework struts and manipulator struts provide the multi-axis machine with increased versatility of operation.

Abstract: Apparatus for loading sheet material into a stamping press comprising a tool releasably mounted on the outer end of a boom. The tool has grippers for picking up and releasing sheet material. The boom is advanced lengthwise into the press where the grippers release the sheet material for stamping. The boom can be swung laterally to a tool-charting position where the tool can be changed easily and safely.

Abstract: Disclosed is a flexible robot arm structure utilizing an elongate skeletal frame member which can be controlled to assume any of a number of curved shapes as in the performance of automated operations. The arm functions somewhat like the body of a snake or an elephant's trunk. The skeletal frame defines a plurality of similar elemental segments disclosed in the form of disc-like structures as well as turns in a helical loading configuration. The helical form includes interleaved flexible helix members interconnected in a chain-link form. Displacement of sections in the arm is accomplished by the action of two separate mechanisms. A deflection mechanism provides power to flex or curve an arm section while a distribution mechanism distributes the curvature along the length of the arm to seek a smooth, circular curve. Illustrative embodiments use hydraulic actuators integral with the frame; however, equivalents are disclosed. The resulting arm is a highly repetitive, mechanical structure.

Abstract: Handling apparatus, in particular a telescopic cylinder having at least one retractable and extendable telescopic part. For handling objects, in particular bobbins of wound packaging material, in conjunction with packaging machines, use can be made of long-stroke telescopic members (10) which effect the automatic movement of a load-bearing pin for each bobbin. The telescopic members (10) can be extended by compressed air and can be drawn in by a tension member (20). The tension member (20) is arranged outside the telescopic member (10), is fixedly anchored by one end, and can be wound up and unwound by the other end. The tension member (20) runs over a deflection wheel (23) arranged at the free end of the telescopic member (10), namely on a piston rod (15) of the same.

Abstract: A machine tool isolation system is disclosed. The preferred system includes a pair of platforms connected by a plurality of legs. A tool is typically connected to one platform, and a workpiece to the other. The legs are able to move one platform with respect to the other which can create vibrations. A base, typically formed by a plurality of legs, is mounted to one of the platforms to support the two platforms and legs connected therebetween. A vibration isolator is disposed between the base legs and the floor or other support on which the entire system is mounted.

Abstract: The present invention relates generally to a metrology framework for determining the position of a first object, such as an operator, relative to a second object when the first object is moved relative to the second object. The metrology framework comprises a plurality of extensible instrument arms that are operatively connected in proximity to the first object and the second object. A sensor is in communication with each extensible instrument arm to provide a signal indicative of the extension of the instrument arm. The combination of the signals can be used to determine the position of the first object relative to the second object in all six degrees of freedom.

Abstract: Flexible robot arms are required for manipulation in environments having difficult access, for example, areas having restricted environments and areas beset with obstacles. An apparatus having various basic elements which are flat, arranged one on top of the other so as to tilt and are connected to one another by means of joints is provided. Here, the individual basic elements are arranged along a stacking axis. Between the individual basic elements, adjusting members, e.g. air chambers are provided which make it possible to set a precise angle between the respective basic elements. Control logic and a control bus with an electric power supply ensure in each adjusting member that the predetermined position is maintained.

Abstract: A linear actuated sealant applicator pump for pumping a sealant into an aperture prior to installation of a fastener in that aperture. An air driven linear actuator translates a cam plate carrying a sealant applicator head from a first position in a first direction spaced from and slightly out of vertical alignment with the aperture to which sealant is to be applied. An adjustable stop limits the translation of the cam plate and injector pump. The actuator then continues in the first direction causing the cam plate to follow a cam slot translating the sealant applicator head in a second direction normal to the first direction toward and in vertical alignment with the aperture with the head engaging the edges of the aperture. The engagement of the head with the edges of the aperture prevents further translation of the sealant applicator head into the aperture.

Abstract: A robotic assembly is provided that simulates the size, appearance and movement of a human torso. The torso includes a unique combination of high speed rotary and linear actuators arranged in a geometry that enables anatomically correct human-like movement, and which provides sufficient internal room and mounting surfaces for the actuators and related equipment such as hydraulic or pneumatic lines, electronic control circuits, valves, and audio playback devices. A preferred embodiment of the present invention provides up to nine degrees of freedom. The upper torso includes a pair of rotary arm actuators ("rotacs") for rotating arms up to 200 degrees. The rotacs are pivotally attached to a centrally located mounting structure for up-and-down motion (shoulder shrugging) and for forward-and-back motion (shoulder forward).

Abstract: A machine such as a machine tool includes a pair of spaced platforms. One platform may mount an operator such as a tool in a spindle, and the other platform may mount an object such as a workpiece. The spaced platforms are joined by six powered and extensible legs joined to the respective platforms by universal joints. The length of the legs is individually manipulated to vary the positions of the platforms and, therefore, the object and operator relative to each other. Four of the legs are arranged into two pairs which are spaced apart to provide between them a part of a corridor for moving the workpiece into a working position. The two legs in each pair may cross each other. The other two legs extend away from each other and provide another part of the corridor between their inboard ends.

Abstract: This invention reveals improvements in a flexible robotic limb which can function as a robotic snake. These improvements are particularly pertinent to miniaturization applications such as catheters or positioners for microsurgery, micro-assembly, micro-manipulation, or micro-exploration. This invention developes detailed new component designs, and it combines the basic structure with systems for sensing, control, and signal transmission. These systems include pressure sensors, length sensors, protective skins, ultrasonic imagers, cutting tools, and multiplexing schemes.

Abstract: A joint of a hydraulic manipulator connects two hollow arm members and includes two indirect linkage members arranged to provide increased scope for the joint. Hydraulic hoses or cables extend through the hollow arm members, so as to be protected, and along a route which intersects the centre axis of the joint so they are not stretched as the joint bends.

Abstract: A force transducer for a robotic arm comprises a plurality of axially-contractible cells. Each cell includes first and second end pieces which are interconnected by a pair of flexible connecting members. The connecting members are disposed on opposite sides of a longitudinal axis. The connecting members are deflected inwardly towards the longitudinal axis by a pair of electromagnets to cause a change in length of the transducer. The transducers can be used to impart movement robotic devices.

Abstract: A machine such as a machine tool includes a pair of spaced platforms. One platform (11, 31, 185, 72, 159, 142) may mount an operator such as a tool in a spindle and the other platforms (10, 20, 180, 170, 144, 163) may mount an object such as a workpiece. The spaced platforms are joined by six powered and extensible legs (20-25, 40-45, 64-69, 145-150, 166, 182-84, 187-89) joined to the respective platforms by universal joints. The length of the legs is individually manipulated to vary the position of the platforms and, therefore, the object and operator relative to each other in six axes. The powered legs may be hydraulic cylinders (20-25) or recirculating ball screw driven (195, 197, 198). The distance between the spaced platforms may be measured by separate extensible instrument arms (130, 131, 171) which join the platforms. The instrument arms may use a digital position device (238, 240) to measure the extension and contraction of the instrument arms or may use a laser interferometer (267) for that purpose.

Abstract: Load-bearing swinging arm which causes an advance movement of a mobile device by means of its pivoting movement is pivotally connected to a supporting structure in a pivotal relationship thereto about an axis of rotation, and a pair of actuators for effecting the pivoting movement is provided between the swinging arm and the supporting structure. The points of action acting on the supporting structure by way of the actuators are provided on both sides of the axis of rotation. The points of action effect moment simultaneously about the axis of rotation, and they will also effect a force couple at least in some position, for example, in a position critical in view of the load, the forces acting through the points of action being parallel, of equal magnitude and having opposite senses in the force couple.

Abstract: The invention is an assembly of a plurality of relatively movable jointed mbers such as robotic arm segments and a mechanical muscle connected between two of the segments. The muscle has a longitudinally inflexible, radially expandable sleeve containing a pressurizable bladder of elastic material. The bladder enlarges diametrically when pressurized and bulges the wall of the sleeve outward. The sleeve thereupon contracts axially to compensate for taken up by the sleeve's outward bulge. A terminus at either end of the sleeve connects the sleeve to different segments of a jointed arm, so that the sleeve's axial contraction effects movement of one segment relative to the other.

Abstract: Surface treating apparatus employing at least two linear motors driving a multiple linkage system for positioning the outlet of treatment apparatus such as a radiation head or a sprayer for coating objects and especially large objects. A combination of different motions such as linear, rotational and a combination thereof are achieved through varying relative speeds and/or selective movements of the linear motors used to drive the multiple linkage system. Treatment of the entire surface area of the item being treated is accomplished through with the number of reduced number of components of simplified design. One dimensional and two dimensional linear motors may be employed in the system. A second embodiment has a plurality of spray assemblies. Each assembly has a single arm and linear motor which moves along two perpendicular axes.

Abstract: A tentacle-like manipulator has a resiliently longitudinally extensible, laterally bendable elongate member, e.g. an inflatable bellows or a helical compression spring-like member, with an end effector mounting on one end thereof. Tendon-like tension members extend along said elongate member and are spaced apart from one another around said elongate member, one end of each of said tension members being to said elongate member at said one end thereof. Guides spaced apart along and secured to said elongate member and slidably engage said tension members for guiding said tension members relative to said elongate member. Further tension members extend along only a portion of the length of the elongate member and are secured to the elongate member at a location intermediate the ends of the elongate member. Winches are used to wind and unwind the tension members to correspondingly control the length and the bending of the elongate member.

Abstract: Apparatus useful in surgery for holding surgical instruments such as retractor blades in a number of different positions required by a surgeon for the performance of a surgical procedure, including an actuation means responsive to a control signal, a signal generating means which enables an operator to generate the control signal and which transmits the control signal to the actuation means, for causing the actuation means to move the surgical instrument.

Abstract: A robotic joint wherein an elongated support member attached at one end to a base has the other end thereof pivotally attached to one end of a lever, the other end of the lever extending away from the support member. A tension strip extends along the support member and over the other end of the lever, the ends of the tension strip being attached to the base on opposite sides of the support member. A pair of bladders positioned between the tension strip and the support member on opposite sides thereof can be inflated to apply a tensile force to the strip and cause the lever to pivot, carring with it a finger which is attached to the lever.