A trio of researchers at University College London have showcased a reliable system for true freedom in 3D printing — by using free-roaming autonomous robots as the printers and the world as their build platform.
"Mobile 3D Printing (M3DP), using printing-in-motion, is a powerful paradigm for automated construction," the team explains of its work. "A mobile robot, equipped with its own power, materials, and an arm-mounted extruder, simultaneously navigates and creates its environment. Such systems can be highly scalable, parallelizable and flexible. However, planning and controlling the motion of the arm and base at the same time is challenging and most deployments either avoid robot-base motion entirely or use human prescribed robot-base paths."
It's here the team sought to improve upon the current state of the art, developing a new M3DP system dubbed Armstone and building on earlier work to create a high-level planning algorithm, which would take the human out of the equation — allowing for as simple a printing process as a traditional 3D printer, whereby a user simply sends a file and the robot trundles off to begin work with no manual route-planning required.
The Armstone robot, built to be low cost, is built on a four-wheel Mecanum base with powerful motors and a six-degrees-of-freedom (6DoF) uFactor xArm robot arm mounted so as to be able to reach an extruder down to the ground. For smarts, the robot carries two Intel NUC small form-factor computers — plus an on-board router, batteries, a compressor, LIDAR sensor, and a cylinder in which the manufacturing material is stored.
In testing, Armstone easily bested previous work in the field: given a multi-layer printing task, the Armstone robot autonomously laid out and printed a project 250 meters (around 820 feet) in length — around five times bigger than the previous record for a printing-in-motion setup and, the researchers claim, "the largest and highest [autonomous] print done with a moving mobile manipulator to date."
The team's work was presented at the IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS '22), with the paper available under open-access terms on ResearchGate.