Abstract: A method for controlling an electron beam process wherein a wire is melted and deposited on a substrate as a molten pool comprises generating the electron beam with a complex raster pattern, and directing the beam onto an outer surface of the wire to thereby control a location of the wire with respect to the molten pool. Directing the beam selectively heats the outer surface of the wire and maintains the position of the wire with respect to the molten pool. An apparatus for controlling an electron beam process includes a beam gun adapted for generating the electron beam, and a controller adapted for providing the electron beam with a complex raster pattern and for directing the electron beam onto an outer surface of the wire to control a location of the wire with respect to the molten pool.

Abstract: A closed-loop control method for an electron beam freeform fabrication (EBF3) process includes detecting a feature of interest during the process using a sensor(s), continuously evaluating the feature of interest to determine, in real time, a change occurring therein, and automatically modifying control parameters to control the EBF3 process. An apparatus provides closed-loop control method of the process, and includes an electron gun for generating an electron beam, a wire feeder for feeding a wire toward a substrate, wherein the wire is melted and progressively deposited in layers onto the substrate, a sensor(s), and a host machine. The sensor(s) measure the feature of interest during the process, and the host machine continuously evaluates the feature of interest to determine, in real time, a change occurring therein. The host machine automatically modifies control parameters to the EBF3 apparatus to control the EBF3 process in a closed-loop manner.

Abstract: A bioreactor with substance injection capability. In one embodiment, the bioreactor includes a first substrate having a first surface, an opposite second surface and edges. The bioreactor further includes a second substrate having a first surface and an opposite second surface, defining a cavity with a bottom surface, where the bottom surface is located therebetween the first surface and the second surface. The first surface of the first substrate is received by the second surface of the second substrate to cover the cavity so as to form a chamber for receiving cells and a liquid medium. A port is formed in the second substrate between the bottom surface and the first surface of the second substrate. As formed, the port is in fluid communication with the chamber to allow a stream of substance to be introduced into the chamber. The stream of substance is controlled so as to provide a gradient, or a concentration gradient of the substance, to the chamber.

Abstract: A bioreactor for cultivating living cells in a liquid medium. In one embodiment of the present invention, the bioreactor includes a first substrate having a first surface, an opposite second surface and edges. The bioreactor further includes a second substrate having a first surface and an opposite second surface, defining a cavity with a bottom surface, where the bottom surface is located therebetween the first surface and the second surface. The first surface of the first substrate is received by the second surface of the second substrate to cover the cavity so as to form a channel for receiving cells and a liquid medium. In forming the bioreactor, the channel is sized to allow the growth of a layer of cells on a biocompatible coating layer and a flow of liquid in the channel. The flow of liquid is controlled so as to provide a known shear force to the layer of cells. The flow of liquid can be further controlled so as to provide an environment that simulates a vascular space in the channel.

Abstract: A bioreactor for cultivating living cells in a liquid medium. In one embodiment of the present invention, the bioreactor includes a first substrate having a first surface, an opposite second surface and edges. The bioreactor further includes a second substrate having a first surface and an opposite second surface, defining a cavity with a bottom surface, where the bottom surface is located therebetween the first surface and the second surface. The first surface of the first substrate is received by the second surface of the second substrate to cover the cavity so as to form a channel for receiving cells and a liquid medium. In forming the bioreactor, the channel is sized to allow the growth of a layer of cells on a biocompatible coating layer and a flow of liquid in the channel. The flow of liquid is controlled so as to provide a known shear force to the layer of cells. The flow of liquid can be further controlled so as to provide an environment that simulates a vascular space in the channel.

Abstract: A closed-loop, feedback-controlled direct laser fabrication system is disclosed. The feedback refers to the actual growth conditions obtained by real-time analysis of thermal radiation images. The resulting system can fabricate components with severalfold improvement in dimensional tolerances and surface finish.

Abstract: A stream of molten material free falls through a drop tube and impinges on a chill surface adjacent the bottom of the drop tube to form rapidly solidified particulate. The chill surface is so inclined and moved relative to the stream of molten material as to have an upward component of motion counter to the downward direction of fall of the stream to significantly enhance shearing and rapid quenching of molten material striking the chill surface. The resulting solidified particulate is discharged from the chill surface for collection in a particulate collection chamber beneath the chill surface. Production quantities of rapidly solidified particulate can be continuously made.