Building (with) human–robot teams: fabrication-aware design, planning, and coordination of cooperative assembly processes

Abstract This research presents a comprehensive methodology for designing and fabricating spatial timber assemblies using cooperative human–robot workflows, enabling the on-site construction of complex structures that exceed the capabilities of humans or robots alone. At the core of this approach is a rule-based design method—termed assembly grammar—which defines not only geometric configurations but also sequences of interdependent physical tasks for assembling reciprocal frame-like structures cooperatively. This methodology integrates user-defined design intentions with equilibrium conditions and fabrication constraints specific to both robotic and manual processes. The design is stored using a graph-based assembly model, which captures geometric information alongside task-related data such as task assignments, robotic fabrication parameters, and assembly sequences. Complementing the design workflow, the methodology also includes strategies for effectively coordinating and distributing tasks between humans and mobile robots, supported by a custom-developed mobile augmented reality (AR) application. To validate the approach, a fabrication-aware design tool was created and applied for generating complex reciprocal-like timber structuresfor scaffold-free in-situ cooperative assembly. The coordinated assembly methodology was then demonstrated through the successful construction of two architectural-scale timber demonstrators built cooperatively by multiple humans and robots. Evaluation criteria such as assembly accuracy and the effectiveness of human–robot interaction demonstrated the practical benefits and applicability of the methodology for real-world construction scenarios.