摘要:
A computer-implemented method is provided for generating the estimation of current position, velocity and acceleration state vectors and associated uncertainty estimation (covariance) of a boosting ballistic missile. The method includes constructing a state tensor of the projectile from a plurality of sensor measurements in Earth-Centered, Earth-Fixed (ECEF) coordinates; translating the state tensor to Cartesian coordinates as a transform state; determining a covariance matrix from the transform state; updating the transformed state as an updated transform state; and updating the covariance matrix as an updated covariance. The process can further include adjusting the covariance matrix by an approximate transition matrix and a process noise matrix. The noise matrix can be translated from a local noise matrix based on a propagation time-step, a scaling parameter, and a bias process noise level. A time-of-flight in the state tensor can be updated by smoothing from a launch event.
摘要:
An apparatus for fabricating integral three-dimensional objects from successive layers of photoformable compositions by exposing the layers of the composition through a semi-permeable film that allows creation of release coatings on the side of the film facing the composition.
摘要:
A method and composition for forming investment casting patterns wherein thermally-collapsible microspheres are incorporated into the pattern composition. The patterns can be made either by conventional pattern forming techniques or by solid imaging techniques. After investing the microsphere containing pattern in the ceramic shell, the pattern and shell are heated, causing a collapse of the microspheres and thereby preventing cracking of the shell. The shell is then heated to burn-out the remaining pattern material and fire the shell, thereby creating a mold.
摘要:
In a solid imaging system, the beam of a relatively high-powered beam radiation source, and more particularly a laser, is modulated in accordance with its varying vector sweep speed so that substantially constant layer depth is maintained at all scanner speeds in a strip of photohardenable composition as it hardens and solidifies in response to the source's irradiation.
摘要:
A computer-implemented method is provided for generating the estimation of current position, velocity and acceleration state vectors and associated uncertainty estimation (covariance) of a boosting ballistic missile. The method includes constructing a state tensor of the projectile from a plurality of sensor measurements in Earth-Centered, Earth-Fixed (ECEF) coordinates; translating the state tensor to Cartesian coordinates as a transform state; determining a covariance matrix from the transform state; updating the transformed state as an updated transform state; and updating the covariance matrix as an updated covariance. The process can further include adjusting the covariance matrix by an approximate transition matrix and a process noise matrix. The noise matrix can be translated from a local noise matrix based on a propagation time-step, a scaling parameter, and a bias process noise level. A time-of-flight in the state tensor can be updated by smoothing from a launch event.
摘要:
A photohardenable composition especially suitable for use in solid imaging. The compositions are characterized by their improved photospeed in combined with excellent initial green strength. The compositions allows for the production of articles by solid imaging processing techniques that show little or no distortion, high accuracy, excellent clarity. The compositions are low in toxicity and have low sensitivity to water.
摘要:
This invention discloses compositions adapted to produce, through solid imaging means, excellent quality objects having material properties that simulate the look and feel of polypropylene articles.
摘要:
Solid objects are formed in an imagewise layering process in which components of a dispersion are homogenized to form an alloy. Imagewise exposure of the layers to radiation to form an alloy permits separation of the exposed, homogenized regions from non-exposed, non-homogenized regions. As each layer is formed and imagewise homogenized, contiguous layer regions are bonded together to form a homogenized, three-dimensional object which may be separated from surrounding dispersion.
摘要:
An apparatus and method for fabricating integral three-dimensional objects from contiguous layers of a photosensitive composition in an imagewise manner, with an additional photogelled portion or photohardened wall, or both, surrounding the three-dimensional object.
摘要:
The invention relates to a radiation curable composition comprising relative to the total weight of the composition (A) 0–29 wt % of a cationically curable component having a linking aliphatic ester group, (B) 10–85 wt % of an epoxygroup containing component other than A, (C) 1–50 wt % of an oxetanegroup containing component, (D) 1–25 wt % of a multifunctional acrylate and a radical photoinitiator and a cationic photoinitiator.