Abstract: Welding using a laser, which leaves keyhole portions at each pass, that allow gases to vent. That keyhole portion is an area within the interior portion, e.g., an inside of a spiral or a circular arc. The keyhole is not processed by the laser and gases can escape. The laser later circles back to process the area.

Abstract: Predictive models of physical parts of the laser processing system part determined. These predictive models are used to determine how the physical system will actually react. The predicted reaction from the models is used as feedback in order to produce the control signals. These physical models therefore adjust to the operation of the system, much in the way that actual feedback would adjust the operation of the system. However, the system may be used at faster speeds, where the actual feedback could not be produced fast enough. Different kinds of modeling are described, including in-position feedback which models sharp movements of the laser system, trajectory models which superimpose the commanded curve over the predicted actual curve to determine errors in trajectory, and constant/variable energy density controls.

Abstract: Predictive models of physical parts of the laser processing system part determined. These predictive models are used to determine how the physical system will actually react. The predicted reaction from the models is used as feedback in order to produce the control signals. These physical models therefore adjust to the operation of the system, much in the way that actual feedback would adjust the operation of the system. However, the system may be used at faster speeds, where the actual feedback could not be produced fast enough. Different kinds of modeling are described, including in-position feedback which models sharp movements of the laser system, trajectory models which superimpose the commanded curve over the predicted actual curve to determine errors in trajectory, and constant/variable energy density controls.

Abstract: Predictive models of physical parts of the laser processing system part determined. These predictive models are used to determine how the physical system will actually react. The predicted reaction from the models is used as feedback in order to produce the control signals. These physical models therefore adjust to the operation of the system, much in the way that actual feedback would adjust the operation of the system. However, the system may be used at faster speeds, where the actual feedback could not be produced fast enough. Different kinds of modeling are described, including in-position feedback which models sharp movements of the laser system, trajectory models which superimpose the commanded curve over the predicted actual curve to determine errors in trajectory, and constant/variable energy density controls.

Abstract: Apparatus is provided which controls humidity in a gas. The apparatus employs a porous interface that is preferably a manifolded array of stainless steel tubes through whose porous surface water vapor can pass. One side of the porous interface is in contact with water and the opposing side is in contact with gas whose humidity is being controlled. Water vapor is emitted from the porous surface of the tubing into the gas when the gas is being humidified, and water vapor is removed from the gas through the porous surfaces when the gas is being dehumidified. The temperature of the porous interface relative to the gas temperature determines whether humidification or dehumidification is being carried out. The humidity in the gas is sensed and compared to the set point humidity. The water temperature, and consequently the porous interface temperature, are automatically controlled in response to changes in the gas humidity level above or below the set point.