Construction 3D Printing

Gantry Concrete 3D Printers are the most common Construction 3D Printers. Characterized by simple linear axis control and high precision, these relatively simple handling systems provide good access to the printable object while making the most of the available workspace.    

The advantage of gantry printers is the increased size of the print area, which allows the construction of small buildings, as well as the use of concrete with the inclusion of coarse aggregate. 

The disadvantage of gantry 3D printers is limited mobility and the need for assembly/disassembly at each construction site. Due to their design, they should always be larger than the object to be printed, since the printing takes place within the area of the printer’s frame. 

Most often, robotic arm concrete printers consist of a print head mounted on a robot, allowing for greater flexibility with a full 6 degrees of freedom, compared to 3 or 4 degrees of freedom in a traditional gantry system. 

The robotic arm controller is essentially a sophisticated computer system that interprets commands, processes data, and orchestrates the coordinated motion of the robotic arm. A micro controller is used to control the material preparation unit and the print head, while the prepared mixture is fed by the pump to the mixing auger located inside the print head. The auger controls the extrusion rate.

To increase the print space, robotic arm printers can be placed on an optional track to make the robot more mobile.

The advantage of a rapidly deployable 3D printer is its mobility. Typically relying on a a type of industrial robot called a Selective Compliance Assembly Robot Arm or Selective Compliance Articulated Robot Arm (SCARA), these machines are generally faster than comparable Cartesian robot systems and their unique design provides high speed and precision printing.

Rapidly deployable SCARA 3D printers are modifications of robotic and gantry construction 3D printers, which are equipped with wheels for easy transport of the printer itself before and after printing. It should be noted that the weight of the printhead of such printers is limited. 

Compared to robotic arm designs, the tangential continuity method offered by SCARA bots provides a smoother transition between print layers, maintaining a constant rate of change in curvature, providing a more aesthetic appearance.