A topology optimization method for collaborative robot lightweight design based on orthogonal experiment and its applications

Abstract

Topology optimization is an effective method for the lightweight of collaborative robots. The extreme working conditions of the robot for the existing topology optimization approach are usually determined by design experience, which may cause mismatch between the chosen load boundary condition of the parts to be optimized and the actual maximum one. In this article, a kind of topology optimization method based on orthogonal experiment was proposed to avoid this mismatch. For this method, the extreme working condition of robots was determined by finding out the combination of robot joint angles when the stress of the part was maximum based on orthogonal experiment. And then, the structure of the part was optimized with the objective of minimizing mass and the constraint of the maximum end displacement of the robots. Finally, the proposed method and the existing method were applied to the lightweight design of a 7 degree of freedom upper limb powered exoskeleton robot, and the results demonstrated that the presented approach can reduce 6.78% maximum end displacement of the robot on average compared with the existing one. It can be concluded that the proposed method in this article is more reasonable and applicable to the structure optimization of collaborative robots.

Research on energy-saving factors adaptability of exterior envelopes of university teaching-office buildings under different climates (China) based on orthogonal design and EnergyPlus

“…A more accurate and reliable optimization conclusion can be obtained with a fewer number of experiments after using an orthogonal design, and it allows for performing both range analysis (R) and analysis of variance (ANOVA) to evaluate test results. There is growing interest in the use of orthogonal design methods for optimization in various fields [ 28 , 51 , 52 , 53 , 54 , 55 ]. Therefore, a university teaching-office building was researched in this paper through orthogonal design and numerical simulation (EnergyPlus) to explore the adaptability (including the optimal parameters and influence degree of each factor of the envelope and the significance levels) of the energy-saving factor of the building envelopes under different climates, which aims to provide the optimal solution for the renovation of university teaching-office building envelopes under different climatic conditions in China to achieve maximum energy-saving building operations.…”