175 results about "Adjustable stiffness" patented technology

Medical devices such as catheters can include structure or provision that permit a physician or other health care professional to adjust the stiffness of at least a portion of the medical device. In some instances, the medical device may be adjusted prior to inserting the medical device into a patient. In some cases, the medical device may be adjusted while in use within the patient.

A medical guidewire system including an inner member having an outer diameter and an outer member having an inner diameter, the inner diameter being larger than the outer diameter. The inner and outer members are relatively slidable to adjust a stiffness of the guidewire system. The lumen of the outer member forms a gap for fluid flow therethrough. A connector has a first end portion connected to the outer member, a second end portion connected to the inner member and a fluid infusion channel communicating with the gap for injection of fluid through the gap to exit a distal portion of the outer member.

The invention relates to a gyroscope with a vibrating structure, produced by micromachining in a thin wafer, which comprises a movable inertial assembly (1) comprising at least one movable mass (50) able to vibrate in the plane of the wafer along a drive axis x and along a sense axis y roughly perpendicular to the x-axis, an interdigital sensor comb (90) and an interdigital drive comb (70). It furthermore comprises at least one additional interdigital comb (10a), called the quadrature-error compensation comb, connected to the mass (50) and which has two asymmetric air gaps e and λe, λ being a positive real number, for subjecting the mass to an adjustable electrostatic stiffness due to coupling between the x-axis and the y-axis by applying a variable DC voltage V to this comb, the adjustable stiffness allowing compensation for the quadrature error of the gyroscope.

In one aspect, the invention provides methods and apparatus facilitating an adjustable-stiffness prosthesis or orthosis (including approximations to arbitrarily definable non-linear spring functions). Spring rates may be varied under no-load conditions during a walking gate cycle to minimize power consumption. In another aspect, the invention provides methods and apparatus for outputting positive power from a prosthesis or orthosis, facilitating high-performance artificial limbs. In one embodiment of the invention, the positive power is transferred from a functioning muscle to the prosthesis or orthosis, which mimics or assists a non-functioning or impaired muscle. In another embodiment of the invention, the positive power comes from an on-board power source in the prosthesis or orthosis.

A system is provided for controlling the load split between the axles and thereby the theoretical wheelbase of a vehicle having two front axles being suspended in suspension units at least some of which have springs with adjustable stiffness. A method for controlling the load split between the axles and to a motor vehicle including such a system and/or by use of such a method is also disclosed.

A catheter has a section of the catheter shaft adjacent its proximal end in which an outer catheter wall and an inner catheter wall define a space therebetween. An electrode is disposed within the space defined between the inner and outer catheter walls. A magnetorheological fluid fills the space between the inner and outer catheter walls. When an electric current is passed through the electrode, the magnetorheological fluid stiffens, causing the section of the catheter shaft adjacent the proximal end to stiffen.

The present invention relates to a catheter that has adjustable stiffness that enables a user to select the stiffness of at least one region of the catheter during insertion and navigation through a body lumen. A preferred embodiment of the invention works in combination with a guidewire to enable placement of the catheter at a position within the vascular system, for example, to enable treatment of a variety of medical conditions. The catheter can include segments that undergo relative movement in response to actuation by the user to adjust the flexibility of the at least one region, preferably located at or near the distal end of the catheter.

Apparatus and methods for an endovascular catheter that can be inserted within tortuous body anatomies and then selectively stiffened and fixed in place. In a particular embodiment, this stiffness is reversible. The stiffness or a comparable mechanical characteristic of the catheter assembly may be adjusted to a relatively low value during insertion (so that it easily navigates a guide wire or the like), and then subsequently adjusted to a relatively high value in situ to keep the catheter assembly substantially fixed in place (i.e., during delivery of an interventional device).

A guidewire assembly having selectively adjustable stiffness and tip curvature includes a hollow guidewire having a distal portion terminating at a distal tip, a curvature-modifying element anchored to the distal tip, and a stiffness-modifying element displaceable within the hollow guidewire towards and away from the distal tip so as to vary a stiffness of the distal portion. The stiffness-modifying element and the curvature-modifying element are frictionally linked such that movement of the stiffness-modifying element from a current position over a first range of motion causes corresponding displacement of the curvature-modifying element, thereby modifying a state of curvature of at least part of the distal portion of the guidewire. Movement of the stiffness-modifying element beyond the first range of motion displaces the stiffness-modifying element relative to the curvature-modifying element.

The invention discloses a magneto-rheological semi-active damper with adjustable stiffness. The damper comprises an outer annular cylinder fixed on the inner wall of a container and an inner cylinder;scrollable balls are arranged between the lower portion of the inner cylinder and a bottom plate of the device, and the inner cylinder and the outer annular cylinder are filled with a magneto-rheological liquid respectively; hollow spring pipes are connected between the cylinder walls of the inner cylinder and outer annular cylinder, the inner cylinder and the outer annular cylinder are communicated with each other through the hollow spring pipes, the magneto-rheological liquid can flow in the inner cylinder and the outer annular cylinder through the hollow spring pipes, the outer portions ofthe spring pipes are provided with magnet exciting coils, the magnet exciting coils, controllers and a solar panel arranged at the outer side of the upper portion of the container are connected in series to form a closed loop circuit, the controllers receive signals of acceleration sensors to control the current in the magnet exciting coils, thereby adjusting the stiffness of the hollow spring pipes and achieving the horizontal damping control; limiting plates are arranged between the outer annular cylinder and the inner cylinder to prevent the inner cylinder from being displaced too much; damping nets are arranged in the outer annular cylinder, and the torsion damping control is achieved through damping force.

The present invention is to provide an improved resilient bra cup structure with adjustable stiffness or softness, wherein the bra cup structure having at least four layers comprising a layer of stiff knitted fabric, a layer of meshed gel, a layer of resilient staple fiber, and a layer of soft knitted fabric. The layer of meshed gel is subjected to a heating process for thermally bonded between the layer of stiff knitted fabric and the layer of resilient staple fiber. Furthermore, the thermally-bonded sandwiched fabric is bonded to the layer of soft knitted fabric for forming a compound fabric to make a bra cup.

The invention discloses an airbag type pressure system, which comprises a flexible object with a closed cavity inside, an inflation booster, an exhaust and pressure relief device, a pressure detector and a central processing unit. The side wall of the flexible object is flexible but Without elasticity, the side wall of the flexible object forms a hardness that is closely and positively related to the internal gas pressure. The central processor monitors the gas pressure inside the cavity of the flexible object through a pressure detector, and adjusts the gas pressure inside the cavity in real time, and then adjusts The overall surface hardness of the flexible object constitutes a support body with adjustable hardness. The airbag pressure system can be applied to cushions such as seat cushions, back cushions, mattresses and massage cushions. By adjusting the gas pressure inside the cavity in real time, a cushion with adjustable hardness can be formed to meet different needs. Occasionally, different needs of different user groups. The invention also provides a medical binding device with the system.

The invention discloses a magneto-rheological adjustable stiffness helical spring, which comprises a helical spring and a ring-shaped external electromagnet or a column-shaped internal electromagnet. Rheological fluid or magnetorheological grease, the outer diameter of the coil spring is smaller than the inner diameter of the ring-shaped external electromagnet and there is a gap, the coil spring is placed in the ring-shaped external electromagnet or the inner diameter of the coil spring is larger than the cylindrical built-in electromagnet The outer diameter of the coil spring has a gap, and the cylindrical built-in electromagnet is placed in the coil spring. The hollow tube of the coil spring wire is a non-magnetic elastic material, which is input to the ring-shaped external electromagnet or the column-shaped built-in electromagnet through adjustment. The magnitude of the current in the magneto-rheological adjustable stiffness coil spring can be adjusted, so that the stiffness of the magnetorheological adjustable stiffness coil spring can be adjusted at any time.

A golf shaft having adjustable stiffness and frequency. A hollow golf shaft has a compression assembly disposed along and within the hollow shaft between the butt end and the bend point of the shaft. The compression assembly places the corresponding end of the shaft in compression and permits rapid and easy adjustment of the shaft stiffness and frequency.

A treadmill (10) includes a frame on which are mounted transverse forward and rearward roller assemblies (14, 16). An endless belt (18) is trained about the forward and rearward roller assemblies. A deck (20) is positioned between the upper run of the belt and the frame. The rearward portion of the deck (20) is mounted to the frame by a pivot connection (24) to allow pivoting of the deck about an axis transversely to the length of the deck. Elongate springs (26) of adjustable stiffness are mounted either along the sides of the frame to underlie the side margins of the deck, or transversely of the deck, to support the deck in conjunction with the pivot connection (24) and to absorb impact loads imparted on the deck by the user.