Randomized multi-objective optimal design of a novel deployable truss

In this article, a novel deployable mechanism that can be depaloyed from a bundle compact configuration onto a large volume double-layer truss structure is proposed. The mechanism is constructed by a set of Myard linkages through specially designed mechanical connections, so that the whole assembled mechanism has single degree of freedom. The model of the multi-objective design for the proposed deployable mechanism is developed. In the optimal design of this mechanism, many design objectives have to be taken into consideration, such as weight, stiffness, packaging/expansion ratio and natural frequency, etc. Many of these design objectives have no explicit analytical expression and may be contradicted with each other. A randomized multi-objective search algorithm is proposed for solving this multi-objective design problem, by using the algorithm, the set of Pareto optimal solutions can be obtained, and the relationship between different objectives is figured out, so that the designers can choose the compromise solutions intuitively. The physical prototype is also fabricated based on the optimized parameters, the stiffness and natural frequency experiments are conducted to evaluate the design. The experimental results demonstrate that the proposed mechanism offers an attractive combination of performance characteristics for both stiffness and natural frequency.