Building and Construction have recently become an exciting application ground
for robotics. In particular, rapid progress in materials formulation and in
robotics technology has made robotic 3D Printing of concrete a promising
technique for in-situ construction. Yet, scalability remains an important
hurdle to widespread adoption: the printing systems (gantry- based or
arm-based) are often much larger than the structure to be printed, hence
cumbersome. Recently, a mobile printing system - a manipulator mounted on a
mobile base - was proposed to alleviate this issue: such a system, by moving
its base, can potentially print a structure larger than itself. However, the
proposed system could only print while being stationary, imposing thereby a
limit on the size of structures that can be printed in a single take. Here, we
develop a system that implements the printing-while-moving paradigm, which
enables printing single-piece structures of arbitrary sizes with a single
robot. This development requires solving motion planning, localization, and
motion control problems that are specific to mobile 3D Printing. We report our
framework to address those problems, and demonstrate, for the first time, a
printing-while-moving experiment, wherein a 210 cm x 45 cm x 10 cm concrete
structure is printed by a robot arm that has a reach of 87 cm.Comment: 6 pages, 7 figur