Lightweight design of a crane frame under stress and stiffness constraints using super-element technique

Abstract

Crane frame is one of the core components of the crane. Important performance indexes for the design of a frame include stiffness, manufacturability, and durability. Simultaneously, lightweight of the frame is also critical for decreasing the consumption of manufacturing and transportation. Crane is a complicated multibody structure, and therefore, using the traditional method to analyze will consume large amounts of computing time, and the accuracy cannot be expected. In order to solve these problems, a novel and effective method, super-element global modal parameterization, is employed in this article. The advantages of using this approach are that the complex models can be reduced, while the important effects are still taken into account. The design procedure consists of three steps: first, the finite element model is used to analyze the original frame. Then, the stiffness and von Mises stress obtained from the analysis are treated as the design constraints in the next topology and thickness optimization. Finally, a validation of the optimum design for durability is performed, and the results show that all the performances satisfy the requirements. The frame structure has a 15.12% reduction in total mass, while the performance is improved compared to the original.

A topology optimization method of robot lightweight design based on the finite element model of assembly and its applications

“…DS is the maximum end displacement of the reference robot and Ds 1 is the end displacement constraint of Part 2 for the topology optimization. Therefore, the end displacement constraint for the topology optimization of Part 2 based on different methods can be calculated by equation (2), as listed in Table 3.…”

“… 1 The collaborative robots, which interact with human being directly during work, have been developed and widely used in all kinds of conditions because the reduced mass and inertia of the robot can cause less harm to human beings when they are collided. 2 For this reason, lightweight design becomes a key point in developing a collaborative robot. And researchers often take two methods for robot lightweight design, one is to use the new type of lightweight materials and another is to optimize part structure.…”

Carbody vibrations of high-speed train caused by dynamic unbalance of underframe suspended equipment

“…The dynamic model of a high-speed EMU operated in China was built using the software package SIMPACK and ANSYS. To provide an acceptable carbody elastic model, the Guyan method 23 is used in model processing to obtain a carbody substructure model. Also, a model test of carbody was conducted to verify the carbody FE model.…”

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

“…With the rise of the new working mode of human-robot collaboration in health care, services, and other unstructured unknown scenes, [1][2][3][4] the safety of the robots has caused much attention. Safety can be increased by reducing the mass and inertia of robots because the harm of the collision between machine and human body 5 could be weakened when the mass and inertia of robots become smaller. Therefore, the lightweight design plays a significant role in improving the safety of robots, 6,7 which can be achieved using new lightweight materials or optimizing the structures of parts.…”