Thermally-actuated composite helical lattices: prediction and - PowerPoint PPT Presentation

Thermally-actuated composite helical lattices: prediction and validation Jonathan P. Stacey, Mark Schenk, Carwyn Ward, Matthew P. O’Donnell CDT Conference 16 th April 2019

2 Presentation Outline • Introduction • Methods • Results • Conclusions JP Stacey, M Schenk, C Ward, MP O’Donnell CDT Conference – 16 th April 2019

3 Introduction • Composites offer unique stiffness tailoring routes • Rich design space available • Thermal response of non- symmetric laminate causes curvature changes • Extreme mechanical behaviour possible JP Stacey, M Schenk, C Ward, MP O’Donnell CDT Conference – 16 th April 2019

4 Methods Analytical • Optimise fibre angles Finite Element Analysis (Abaqus) + HEAT • Shell models, quasi-static • Parameter sensitivities : length, width, joint type, friction, prestress Experimental • Temperature-Extension • Force-Extension JP Stacey, M Schenk, C Ward, MP O’Donnell CDT Conference – 16 th April 2019

5 Results • Good match between FE and experiment • Achieved extreme negative CTE (-3285·10 -6 K -1 ) • Beam vs Shell models • Joint friction and end effects less significant JP Stacey, M Schenk, C Ward, MP O’Donnell CDT Conference – 16 th April 2019

6 Conclusions Future Work • Working prototype composite • Explore dynamic snapping helical lattice structure behaviour • Improve manufacturing • Extreme behaviour can be robustness designed and realised • Good correlation between experiments and FE analysis • Some key parameter sensitivities investigated JP Stacey, M Schenk, C Ward, MP O’Donnell CDT Conference – 16 th April 2019

Thank You jonathan.stacey@bristol.ac.uk