Abstract: A freeform extrusion fabrication process for producing three-dimensional ceramic, metal and functionally gradient composite objects, including the steps of filling a plurality of paste sources with a respective plurality of aqueous paste compositions, operationally connecting respective syringes containing respective aqueous paste compositions to a mixing chamber, moving a first aqueous paste composition from a first respective paste source into the mixing chamber, moving a second aqueous paste composition from a second respective paste source into the mixing chamber, mixing the first and second aqueous paste compositions to define a first admixture having a first admixture composition, extruding the first admixture onto a surface to define an extruded layer having a first admixture composition, surrounding the sides of the extruded layer with an oil bath, radiatively drying the extruded layer.

Abstract: A freeform extrusion fabrication process for producing three-dimensional ceramic, metal and functionally gradient composite objects, including the steps of filling a plurality of paste sources with a respective plurality of aqueous paste compositions, operationally connecting respective syringes containing respective aqueous paste compositions to a mixing chamber, moving a first aqueous paste composition from a first respective paste source into the mixing chamber, moving a second aqueous paste composition from a second respective paste source into the mixing chamber, mixing the first and second aqueous paste compositions to define a first admixture having a first admixture composition, extruding the first admixture onto a surface to define an extruded layer having a first admixture composition, surrounding the sides of the extruded layer with an oil bath, radiatively drying the extruded layer.

Abstract: This novel technology relates to a freeze-form extrusion fabrication process for fabricating three-dimensional functionally gradient composite parts by extruding and mixing multiple aqueous pastes prior to depositing and freezing the mixed paste, layer by layer, using a computer controlled multi-extruder apparatus. Various aqueous pastes with low organic binder contents are first prepared. The extrusion of each different paste is coordinated through computer control, which mixes the pastes in any desired proportions prior to extrusion through and deposition according to a pre-programmed deposition path for each layer. The mixed paste is frozen immediately after deposition. A heating jacket may be used to prevent the pastes from freezing prior to deposition. The layer-by-layer fabrication process continues until an entire part has been fabricated.

Abstract: The invention relates to a computer-aided process of dental bar design for the purpose of fabricating removable implant-based dental restorations. The aim of the invention is to improve and automate the present dental restoration design process, which is very labor intensive and requires a lot of artistic work on the part of a dentist. The invention includes the developments of several algorithms and their integration into a computer-aided system to process the gingival and related data scanned from a patient's mouth and output a CAD model for fabricating the actual dental bar. Software has been developed to implement the inventive process.

Abstract: Embodiments of the present invention provide a method implemented by a computer program for detecting and identifying valve failure in a reciprocating compressor and further for predicting valve failure in the compressor. Embodiments of the present invention detect and predict the valve failure using wavelet analysis, logistic regression, and neural networks. A pressure signal from the valve of the reciprocating compressor presents a non-stationary waveform from which features can be extracted using wavelet packet decomposition. The extracted features, along with temperature data for the valve, are used to train a logistic regression model to classify defective and normal operation of the valve. The wavelet features extracted from the pressure signal are also used to train a neural network model to predict to predict the future trend of the pressure signal of the system, which is used as an indicator for performance assessment and for root cause detection of the compressor valve failures.

Abstract: A system for using a virtual reality environment to create a design model and generate numerically controlled (NC) machining trajectories for use in fabrication of the model. The model is created in a virtual environment by carving a workpiece with one or more tools, each of which may have the geometry of a hand tool (e.g. a knife) or a machining tool (e.g. milling cutter). The selection and manipulation of virtual objects is performed in virtual space. Swept volumes of the virtual objects are generated using a solid modeling system according to the shape of the virtual objects and their trajectories, and Boolean operations are performed on the swept volumes and the initial virtual stock (workpiece) to create the design model. If the virtual object has the geometry of a computer numerical control (CNC) machining tool, the real NC machining trajectories for making the design object can be generated from the virtual object's movements, during the design model creation with the virtual reality environment.

Abstract: This invention describes a rapid tooling process that integrates solid freeform fabrication (SFF) with electroforming to produce metal tools including molds, dies, and electrical discharge machining (EDM) electrodes. An SFF part is metalized by electroless plating and then placed in an electroplating solution, where metal is deposited upon the part by electrolysis. When the desired thickness of metal has been reached, the SFF part is removed from the metal shell. The shell is then optionally backed with other materials to form a mold cavity, and EDM electrode, or other desired parts for tooling. Thermomechanical modeling and numerical simulation with finite element analysis (FEA) is used to determine the geometry of the SFF part and the electroform thickness for minimizing the manufacturing time and cost while satisfy the tooling requirement.

Abstract: A method and apparatus for forming three-dimensional patterns by depositing a crystalloid material onto substrate in a layer by layer fashion. The apparatus includes a computer responsive for controlling the material depositing rate and the three-dimensional relative movement between the depositing head and the substrate. The controlling information comes from the sliced CAD model of the part. For each cross-section, the depositing head plots the boundary and the interior while the building material comes out of the head. The crystalloid material deposited on the substrate or previous layer of the part rapidly freezes forming a new layer of the part. The material can be deposited by a continuous extruding device or a drop-on-demand device. Where necessary, support structure is built in the same way but with material of a different melting point.

Abstract: An optical displacement measuring apparatus utilizing triangulation, includes a laser for projecting a laser light beam with a first optical axis onto a surface of an object whose displacement is to be measured; an array of photodetectors for receiving light reflected from the object and for generating a positional signal as an image displacement .delta.; a condensing lens for receiving the light reflected from the object and for supplying the reflected light to the detector array along a second optical axis intersecting the first optical axis at angle .theta., the detector array being inclined at an angle .phi. with respect to the second optical axis; a determining device for non-linearly determining surface displacement as a function of the image displacement .delta. and the angles .phi. and .theta., with the relationship between the image displacement .delta., the surface displacement and the angles .phi.and .theta. always being identical, regardless of the angle .phi..