Light-Weight Topological Optimization for Upper Arm of an Industrial Welding Robot

Abstract

To reduce weight and improve overall performance of the industrial welding robot, light-weight design using the finite element method and structural topological optimization is presented in this paper. The work analyzed an upper arm of an industrial welding robot in the most unfavorable working condition, both under static and dynamic working situations, using ABAQUS and ADAMS software tools. Then the Tosca unit in ABAQUS was employed to accomplish the structural topological optimization, in order to reduce weight and improve the natural frequencies under the situation of low orders. The analyses results showed that the actual weight had been reduced to 17.9%, and the natural frequencies in low orders had increased. The maximum Mises stress, tensile stress, and elastic displacement of the gyration center had decreased. Lastly, an actual product was produced according to the model obtained from preceding analyses. The experiments of the repeatability tests showed that the overall performance of the optimized upper arm had been improved when compared to the original one. This research can present references and foundations for the kinetic analyses under the static and dynamic working conditions, and structural topological optimization designs for relative industrial welding robots.

Automation of the Design of the Cross-Section of the Manipulator Arms Profile

“…without deformations caused by external loads or their weight. In the real world, however, we can only approach the properties of an absolutely rigid body for individual elements of the proposed mechanisms, using, for example, materials with better mechanical properties [Pandey 2017, Lee 1993, appropriately modifying the dimensions, shape or structure of the proposed mechanism elements or using optimization software tools [ Rueda 2009, Yao 2019, Paška 2020. At the same time, there is an effort to achieve the lowest possible weight, moments of inertia and dimensions of the proposed elements or the entire proposed device.…”

Design of the Joint Motor for an Articulated Robot Considering Joint Load Characteristics

“…As a constraint condition on stress analysis, one end of the link was fixed, and a static load was applied to the free end. The static load composed of the force and moment due to the weight of each component of robot, and payload [8,9]. The maximum static load that each link should support was calculated, and loads of 133.2 N and 48.75 Nm were applied to the lower link and 96.7 N and 10.95 to the upper link.…”

Fuzzy Design Optimization-Based Fatigue Reliability Analysis of Welding Robots

“…The output of the GAPSO-RBFNN surrogate model is taken as the fitness value of INSGA-III, and the structure optimization of welding robot is expanded by combining with the fuzzy membership function. According to the membership function and related solving steps given in (11), the fuzzy constraints suitable for optimization are obtained. Table 4 shows the fuzzy allowable interval of optimization variables and the fuzzy design optimization results are described in Fig.…”

“…In view of these two aspects of research, Luo et al [10] employed topology optimization technology to optimize the structure arm of the welding robots, which not only realized the lightweight design of the structure, but also improved the welding accuracy. Yao et al [11] introduced the dynamic analysis method of welding robots upper arm into the topological optimization process of the structure, and realizes the lightweight of the whole robots and the improvement of the natural frequency. Different from the above two optimization processes, Poruba et al [12] studied the strength analysis and optimization of the welding robots mechanism in emergency stop state, and quantifies the peak values of the stress caused by the dynamical component of loading and highlights the potential risks associated with this phenomenon.…”