Additive manufacturing system and method for printing three-dimensional parts using velocimetry

摘要

An additive manufacturing system that retains a print head for printing a three-dimensional part in a layer-by-layer manner using an additive manufacturing technique, where the retained print head is configured to receive a consumable material, melt the consumable material, and extrude the molten material. The system also includes a velocimetry assembly configured to determine flow rates of the molten material, and a controller assembly configured to manage the extrusion of the molten material from the print head, and to receive signals from the velocimetry assembly relating to the determined flow rates.

主权项

1. An additive manufacturing system comprising:
a print head configured to print a three-dimensional part in a layer-by-layer manner using an additive manufacturing technique, wherein the print head is configured to receive a consumable material, melt the consumable material, and extrude the molten material as a continuous length for printing in the layer-by-layer manner; a velocimetry assembly configured to measure an instant velocity of the molten material to calculate an instant flow rate of the molten material, wherein the velocimetry assembly comprises: a light source, and optionally, one or more optical lenses, which are configured to route a plurality of pulses of light from the light source towards the molten material, wherein the molten material causes light rays of the plurality of pulses of light to scatter; and a detector having a sensor configured to receive at least a portion of the scattered light rays, and wherein the detector is configured to receive the scattered light rays in a transmission-forward-scatter pattern in a plurality of frames wherein each frame is converted to a speckle pattern and to transmit the signals relating to the speckle pattern in the plurality of frames to a controller assembly; and wherein the controller assembly is configured to receive signals from the velocimetry assembly relating to the speckle pattern in the plurality of frames by measuring spatial shifts of the speckle pattern over the plurality of frames and to calculate the instant flow rate to manage the extrusion of the molten material from the print head based on the calculated instant flow rate.