Clay Robotics: Tool making and sculpting of clay with a six-axis robot

Abstract

The objective of the project is to design a reproducible clay sculpting process with an industrial robotic arm using parametric con- trol to directly translate mesh geometry from Computer Aided Design (CAD) environment into a lump of clay. This is accomplished through an algorithmic design process developed in Grasshopper using the C# programming language. The design process is enabled by our robotics modelling and simulation library which provides tools for kinematics modelling, motion planning, visual simulation and networked com- munication with the robotic system. Our process generates robot joint axis angle instructions through inverse kinematics which results into linear tool paths realised in physical space. Unlike common subtrac- tive processes such as Computer Numeric Control (CNC) milling where solid material is often pulverised during machining operations, our process employs a carving technique to remove material by dis- placement and deposition due to the soft and self-adhesive nature of the clay material. Optimisation of self-cleaning paths are implemented and integrated into the sculpting process to increase pathing efficiency and end product quality. This paper documents the process developed, the obstacles faced in motion planning of the robotic system and dis- cusses the potential for creative applications in digital fabrication us- ing advanced machines that in certain terms exceed human capability yet in others are unable to reach the quality of handmade works of art.