Additive manufacturing (AM), known also as 3D printing, is a manufacturing process that creates parts by addition rather than subtraction (through milling, for example). AM is mostly used in prototyping but recently it is expanding into many new applications. Recent developments have made it possible to print metals in addition to polymers. Objects with significantly greater complexity can be easily produced compared with conventional processes. With AM this complexity does not increase the cost of the process. As a result, a significantly greater design freedom is provided for the designer. With more sophisticated designs, AM can reduce weight but optimum design can also increase stiffness or reduce vibration.
ROD-IS director, Professor OBrien, did his PhD in Structural Optimisation in the 1980’s. Since then he has used optimisation in many other fields such as optimal bus routeing or finding the pavement profile which minimises the squared differences between measured and theoretical accelerations in a passing vehicle. With increased computation power, he has now moved to using Evolutionary Algorithms. While the Genetic Algorithm is the best known of these, others are more computationally efficient such as Cross Entropy. While many working in Optimisation are from a Mathematical background, the ROD-IS team of Structural Engineers have a strong appreciation of the Engineering issues in design. For example, Professor OBrien was the first to extend topological optimisation to geometrically nonlinear structures. In contrast to the allowable stress approaches in the literature, this ensures stability and prevents the emergence of impractical solutions with very slender compression elements.