Active self-shaping non-newtonian fluid based system and method for rapid mold tooling

A method of rapid mold tooling fabrication using a non-Newtonian shear thickening fluid (STF), the method comprising:

• providing a molding unit including:
• a frame encompassing a fabrication area,
• a plurality of actuatable hydraulic pillars arranged in a two-dimensional array, wherein each hydraulic pillar extends in a first direction to a distal end and is configured to be extended or retracted along the first direction;
• an expandable STF chamber comprising a first preform layer and an opposing second preform layer, wherein the first preform layer is a boundary layer and extends across the distal ends of the hydraulic pillars such that the pillars push or pull against the boundary layer when extended or retracted, and wherein the second preform layer is an interface layer having an outer surface against which a finished mold can be formed,
• a fluid storage unit for storing the STF and configured to pump the STF into the STF chamber during operation,
• an electrical charge source electrically coupled to a signal emitter circuit provided at one or more of the first and second preform layers, wherein the electrical charge source and signal emitter circuits are configured to output an electric signal suitable for transitioning the STF from a liquid to a solid state, and
• a controller, the controller comprising a non-transitory computer readable storage medium and a processor electronically coupled to the storage medium, the electrical charge source and the fluid storage unit, wherein the processor is configured by executing instructions stored on the storage medium;
• defining, using the molding unit, a preform mold for forming a finished mold having a prescribed shape, wherein the step of defining the preform mold includes:
• selectively adjusting a respective length of the plurality of pillars according to the prescribed shape,
• pumping, a volume of STF from the fluid storage unit into the fluid chamber, and
• applying, with the electrical charge source via the signal emitter circuit, the electric signal to the STF within the chamber and thereby transitioning the STF from a liquid to a solid state;
• placing a material to be molded into the finished mold against the interface layer;
• compressing the material against the interface layer thereby imparting the prescribed shape onto the material;
• and
• after a curing period, releasing the finished mold having the prescribed shape from the interface layer.

A method of rapid mold tooling fabrication using active self-shaping non-newtonian fluid, the method comprising:

• providing a molding system comprising two molding units, each molding unit including:
• a frame encompassing a fabrication area,
• a plurality of actuatable hydraulic pillars arranged in a two-dimensional array, wherein each hydraulic pillar extends in a first direction to a distal end and is configured to be extended or retracted along the first direction,
• an expandable STF chamber comprising a first preform layer and an opposing second preform layer, wherein the first preform layer is a boundary layer and extends across the distal ends of the hydraulic pillars such that the pillars push or pull against the boundary layer when extended or retracted, and wherein the second preform layer is an interface layer having an outer surface against which a finished mold can be formed,
• a fluid storage unit for storing the STF and configured to pump the STF into the STF chamber during operation,
• a signal emitter circuit provided at one or more of the first and second preform layers, wherein the signal emitter circuit is electrically coupled to an electrical charge source configured to output an electric signal via the signal emitter circuit that is suitable for transitioning the STF from a liquid to a solid state, and
• the molding system further comprising a controller, the controller including a non-transitory computer readable storage medium and a processor electronically coupled to the storage medium, the electrical charge source and the fluid storage unit, wherein the processor is configured by executing instructions stored on the storage medium;
• and
• measuring, using the first and second molding units, geometric properties of an object placed within the fabrication area between the first and second molding units, the measuring step including the steps of:
• while the pillars of each of the first and second molding units in at least a partially extended state and the STF within the chamber of the first and second molding units is in a viscous state, closing the first and second molding units around the object such that the pillars and STF of the first and second molding units conform to the object,
• applying an electrical signal to the STF within the STF chamber of each the first and second molding units to transition the STF to a rigid state,
• determining, for each the first and second molding units, respective system parameters including a respective position of the pillars, and
• determining the geometric properties of the object from the measured respective system parameters.