Science, Inc.

Livermore Software Technology Corporation

Other

William W Feng

Marshall S Kriesel

Farhad Kazemzadeh

Matthew B Kriesel

William J Kluck

Steve C Barber

John O Hallquist

Thomas N Thompson

Steven C Barber

Paul A DuBois

Methods and systems for enabling simulation of material aging effect of chrono-rheological materials in computer aided engineering (CAE) analysis are disclosed. According to one aspect, a set of material property tests is conducted for a chrono-rheological material of interest. Each test obtains a series of material properties such as relaxation test data at different age. The relaxation test data are measured by maintaining a specimen of the chrono-rheological material at a predetermined strain. A set of first and second time-dependent material aging effect parameters is determined by shifting and matching the series of relaxation test data between each pair of the tests. The set of first and second time-dependent material aging effect parameters in conjunction with a CAE analysis application module with a chrono-rheological material constitutive equation configured therein are then used for simulating material aging effect by performing a CAE analysis of an engineering structure containing at least in part the chrono-rheological material.

Methods and systems for enabling simulation of aging effect of a chrono-rheological material in computer aided engineering analysis

Systems and methods for determining material properties of elastomers for the Mullins effect are described. In one aspect of the present invention, material properties of an elastomer membrane specimen are obtained using a system comprising a bi-axial test device, a pump, a fluid reservoir, a linear variable differential transformer, a pressure transducer and a computer. The bi-axial test device comprises a top plate and a bottom plate. The top plate has an elliptical shape hole configured to allow the specimen to be expanded up by pressures of the inflating fluids. The hole is so dimensioned that the specimen can be expanded with a relatively low pressure. The bottom plate is a solid plate configured with a fluid intake at one side and a fluid outlet at the other end. The fluid intake is connected to the fluid reservoir. Fluids stored in the fluid reservoir are pumped into the bi-axial test device by the pump. The fluid outlet is connected to the pressure transducer.

Determination of elastomer material properties for the Mullins effect using a bi-axial test device

Systems and methods for determining material properties of elastomers for the Mullins effect are described. In one aspect of the present invention, material properties of an elastomer membrane specimen are obtained using a system comprising a bi-axial test device, a pump, a fluid reservoir, a linear variable differential transformer, a pressure transducer and a computer. The bi-axial test device comprises a top plate and a bottom plate. The top plate has a circular hole configured to allow the specimen to be expanded up by pressures of the inflating fluids. The circular hole is so dimensioned that the specimen can be expanded with a substantially low pressure. The bottom plate is a solid plate configured with a fluid intake at one side and a fluid outlet at the other end. The fluid intake is connected to the fluid reservoir. Fluids stored in the fluid reservoir are pumped into the bi-axial test device by the pump. The fluid outlet is connected to the pressure transducer.

A method and system to numerically simulating structural responses of a highly compressible material such as foam in finite element analysis is disclosed. According to one aspect of the simulation, a new improved method for calculating structural responses is derived using the following assumptions: uniaxial loading and isotropic material. As a result of the new method, Ogden polynomial stress function f(&#x3bb;) is replaced by a tabulated function depending upon only a set of stress-strain curves obtained via uniaxial tension and compression tests. The method is implemented in a finite element analysis software product.

Method and system for numerically simulating foam-like material in finite element analysis

A fluid operated timing device in which the timing interval is determined by the rate at which the fluid flows through a precisely configured rate control frit upon being forced through the frit by an energy source in the form of a compressible elastomeric member.

Timing device

A compact, patient controlled fluid dispenser for use in controllably dispensing fluid medicament at a selected uniform rate. The device is of an all mechanical construction and is ideally suited for the reliable patient administration of pain killing drugs in the home care environment. To positively regulate the patient administration of the medicament, the intervals at which a selected medicament can be administered, as well as the volume of the dose of the medicament to be administered, is preset by the treating physician and, once set, cannot be altered by the patient. More particularly, the device setting can only be operated by a small physician's key that remains in the possession and control of the treating physician or health care worker.

Patient controlled fluid delivery device

An apparatus for accurately infusing fluids into a patient at specific rates over an extended period of time. The apparatus is of a low profile, laminate construction having a stored energy source in the form of a distendable membrane, which in cooperation with the base of the apparatus defines one or more fluid reservoirs each having a fluid inlet and a fluid outlet. The apparatus further includes a novel, conformable ullage made of formable materials. The conformable ullage uniquely conforms to the shape of elastomeric membrane as the membrane returns to its less distend configuration and in so doing can move between a central chamber and a toroidal chamber formed in the cover of the apparatus. This arrangement will satisfy even the most stringent medicament delivery tolerance requirements and will elegantly overcome the limitations of materials selection encountered in devices embodying solely rigid ullage construction. Additionally, the infusion cannula of the apparatus is connected to the base in a novel manner which permits expeditious subdermal delivery to the patient via a cannula which extends generally perpendicularly relative to the base.

Fluid delivery device

A fluid delivery apparatus for continuous basal infusion, together with controlled bolus infusion of injectable medicaments, which embodies a stored energy source such as distendable elastomeric membrane which cooperates with a base and a conformable ullage to define a fluid reservoir and one which includes a unique fill assembly for use in controllably filling the fluid reservoir. The novel fill assembly of the invention enables the fluid reservoir of the fluid delivery portion of the apparatus to be aseptically filled in the field with a wide variety of selected medicinal fluids.

Fluid delivery device with conformable ullage and fill assembly

A fluid delivery apparatus which embodies a stored energy source such as distendable elastomeric membrane which cooperates with a base and a conformable ullage to define a fluid reservoir and one which includes a unique fill assembly for use in controllably filling the fluid reservoir. The novel fill assembly of the invention enables the fluid reservoir of the fluid delivery portion of the apparatus to be aseptically filled in the field with a wide variety of selected medicinal fluids.

A fluid delivery device having a self-contained stored energy membrane for expelling fluids at a precisely controlled rate which is of a compact, laminate construction. The device also includes a novel adapter which is usable to fill the reservoir of the device using a compatable filling syringe apparatus which is mateable with the adapter.

Fluid delivery device with fill adapter

An apparatus for accurately infusing fluids into a patient at specific rates over an extended period of time. The apparatus is of a low profile, laminate or layered construction having a stored energy source in the form of a distendable membrane which, in cooperation with the base of the apparatus, defines one or more fluid reservoirs, each having a fluid inlet and a fluid outlet. The apparatus further includes, a novel, conformable ullage made of yieldable materials which uniquely conforms to the shape of the elastomeric membrane as the membrane returns to its less distended configuration. This arrangement will satisfy even the most stringent medicament delivery tolerance requirements and will elegantly overcome the limitations of materials selection encountered in devices embodying solely a rigid ullage construction. Additionally, in one form of the invention, the infusion cannula of the apparatus is connected to the base of the apparatus in a novel manner which permits expeditious subdermal delivery of liquid medicaments to the patient via a cannula which extends generally perpendicularly from the base.

Fluid delivery device with bolus injection site

A fluid delivery device for infusing medicinal fluids having a self-contained stored energy membrane for expelling fluids at a precisely controlled rate. The device is of a compact, low profile, laminate construction so that it can conveniently be used for the fluids, such as insulin and the like, into an ambulatory patient at controlled rates over extended periods of time. Included within the device are various fluid flow control elements including a unique hydraulic fluid rate control system for ultra low flow delivery. Also included is a highly novel flow indictor for providing a positive indication of fluid flow from the device and for indicating at any given time the amount of fluid remaining in the device.

Fluid delivery device with flow indicator and rate control

An apparatus for accurately infusing fluids into a patient at specific rates over an extended period of time and the method for making same. The apparatus includes one or more dispensers of a low profile, laminate or layered construction each having a stored energy source in the form of a distendable membrane or an elastomeric cellular mass, which in cooperation with the base, defined a fluid chamber having a fluid inlet and a fluid outlet. The apparatus further includes, in lieu of a rigid ullage, a high novel, conformable ullage made of yieldable materials. The conformable ullage uniquely conforms to the shape of elastomeric membrane as the membrane returns to its less distended configuration. This arrangement will satisfy even the most stringent delivery tolerance requirements and will elegantly overcome the limitations of materials selection encountered in devices embodying the rigid ullage construction. Additionally, with the novel ullage construction, the ullage can be located either between the base and the fluid to be delivered, or alternatively, can be located between the elastomeric membrane and the fluid to be delivered. Further, a plurality of subreservoirs can be associated with a single ullage thereby making it possible to incorporate a wide variety of delivery profiles within a single device.

Fluid delivery apparatus

An apparatus for accurately infusing fluids into a patient at specific rates over an extended period of time. The apparatus is of a low profile, laminate or layered construction having a stored energy source in the form of a distendable membrane, which, in cooperation with the base of the apparatus, defines one or more fluid reservoirs, each having a fluid inlet and a fluid outlet. The apparatus further includes, a novel conformable ullage made of yieldable materials. The conformable ullage uniquely conforms to the geometry of elastomeric membrane as the membrane returns to its less distended configuration and in so doing can move between a central chamber and a toroidal chamber formed in the cover of the apparatus. This arrangement will satisfy even the most stringent medicament delivery tolerance requirements and will elegantly overcome the limitations of materials selection encountered in devices embodying solely a rigid ullage construction. Additionally, the infusion cannula of the apparatus is connected to the base in a novel manner which permits expeditious subdermal delivery to the patient via a cannula which extends generally perpendicularly relative to the base.

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Lafayette, CA, United States of America

William W Feng