Graphical Symbols to Communicate Shape Transformation for the Technical Documentation of Products

The use of Shape Memory materials has gathered more widespread use in medical, aerospace and automotive sectors. When combined with Additive Manufacturing processes, Shape Memory materials can be produced for a much wider variety of applications. 4D Printed parts that utilize shape memory and stimuli responsive materials can be programmed for transformation, actuation and self-assembly. However, to reach a high level of industrial maturity, there is an urgent need to develop standards for representing the shape transformations of 4D Printed parts. Establishing these standards would aid the design engineer to accurately communicate the functional requirements for manufacturing as well as to stakeholders across the value chain. Adoption by metrologists and test engineers would aid the quality control of the product to meet QA requirements. The presentation provides a background to this study and proposes a new standard to be used within technical product documentation, geometric product specification and engineering drawings within British Standard BS 8888. Three concepts are introduced: the Shape state (Sn) to define each function of the 4DP part, the Transformation Control Frame (TCF) to define the rules for transforming between Shape states and the Bill of Transformations (BoT) to define the intended sequence(s) of Transformation Control Frames (TCF) to fully describe the part’s shape transformations in the time domain. Lastly, to illustrate how the proposed standard could be applied, use-cases with different shape transformation properties are considered in a workflow.