Industrial engineers craft first plant-ready 3D concrete printer

Robotics and manufacturing automation specialist USABotics cites commercial debut of 3D concrete printing equipment in the North American market through a new entity, MudBots, and charter model. The MudBots 664 Concrete Printer consists of a rectangular, gantry-like CNC (computer numerical control) table whose robotic devices operate on XYZ axes to place low slump mixes in cord-like layers or beads through round nozzles—at rates up to 340 inches per minute.

MudBots unveiled the Model 664 at the 2019 World of Concrete show in Las Vegas.
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MudBots engineers characterize the 664 as a work envelope-optimized cartesian printer powered by IP65 direct drive NEMA 34 hybrid stepper motors. They run in a servo loop controlled by field-programmable gate arrays and administered by LinuxCNC (computer numeric control) running on a real-time operating system. The elements combine to form a low jerk, high payload system with repeatability > .1 inches. Engineers fully integrate the mixing and concrete delivery platform into the LinuxCNC, allowing operators to load the extrusion nozzle material with on-the-fly flow rate and outfeed pressure control.

The 664 measures 8- x 7- x 6.5-ft. and prints products up to 6- x 6- x 4-ft. in layers or wall thickness up to 8 in. Along with extrusion pump and adjustable extrusion head, the model includes batch and pump delivery components for production and transfer of mixes designed with up to ½-in. aggregate and typically bearing rheology modifying admixtures to maintain tight layer tolerances. The 664 is based on a mortar printer USABotics delivered to a statue and monument customer in 2017, and serves as a template for models capable of printing concrete structures up 100- x 100- x 25-ft.

In addition to production components, the MudBot package includes USABotics’ Simplify3D slicing software, which controls all aspects of the print from basic parameters, such as layer height and line speed, to complex infill patterns and percentages. The equipment executes in mortar or concrete products or objects generated on any 3D software and imported to Simplify3D.

“Our ground-breaking 3D printer will provide a test bed for advanced cement or mortar mixtures, and enable architects and engineers to challenge design paradigms and explore possibilities that were not previously available with cast-in-place or pre-cast methods,” says USABotics CEO James Lyman. Just as it has revolutionized discrete part mechanical design and workflow over the past five years, he adds, “3D printing will redefine the manner in which architects and structural engineers think about job solutions and broaden their tools for Industry 4.0. MudBots seeks to automate the manual-labor-concentrated construction sector.”s

“With our Concrete Printers, users simply position the printer over the intended space and hit PRINT. They can print homes, garages, monuments, barbeques, waterfalls, retainers, boulders, or any other unique and free-form design,” Lyman observes. “This new technology will enable contractors and product developers to produce faster solutions at reduced costs to the consumer. The efficiency, quality control, and automation in regards to production will result in higher profit margins.”

3D Concrete Printers are not restricted to creating objects based on straight forms, MudBots notes, as they can output spiral columns and posts, along with a vast array of designs featuring contoured walls. Architects are already coming up with new free-form design elements that will incorporate 3D Concrete Printer capabilities.

The company is developing a dealer program under which 664 or other model customers have defined territories in states, regions or metropolitan areas. It is also seeking to partner with batch plant equipment manufacturers, packaged mortar or concrete mix producers, plus admixture companies. MudBots, Lindon, Utah, 800/733-2302;