Simulation and Ergonomic Evaluation of Welders’ Standing Posture Using Jack Software

Abstract

Ergonomics research strives to make workers’ labor more efficient, safer, and more comfortable. Therefore, six digital humans and welding torch model were built and evaluated based on the Jack software in order to improve the ergonomics of welders’ standing postures. Three sets of standing welding actions were designed: walking, raising arm, and contracting arm. Through the Lower Back Analysis, Ovako Working Posture Analysis, Comfort Assessment, and Rapid Upper Limb Assessment, this paper evaluated the optimum range of the weight of the welding torch, the upper limb posture, and the neck posture of the welder. Firstly, the results show that Chinese welders should not use a welding torch with a weight of more than 6 kg when standing up. Secondly, for adult males in the 5th, 50th, 95th percentile of body size, the best operating distance is 321 mm, 371 mm, and 421 mm, respectively, and the best operating height is 1050 mm, 1100 mm, and 1150 mm, respectively; for females in the same percentiles, the optimal operating distance is 271 mm, 321 mm, and 371 mm, respectively, and the optimal operating height is 1000 mm, 1050 mm, and 1100 mm, respectively. Moreover, the horizontal and vertical rotation angle of the welder’s neck should not exceed 15° and 8.7°. The adjustment strategy not only has a positive effect on improving welders’ operational posture and preventing fatigue and injury to the welder, but it also develops research ideas for promoting safety from the perspective of ergonomics.

A Biomechanical Waist Comfort Model for Manual Material Lifting

“…The main advantage of Jack is its flexible, realistic and detailed three-dimensional human model, especially the models of the hand, spine, shoulder and other parts. The digital human model in the software is composed of 71 segments and 68 joints, and we can also customize the dimensions of the digital human body [ 36 ]. Jack supports the professional ergonomics evaluation system, which can statistic analyze physiological parameters like the posture, force and fatigue parameters through a virtual environment.…”

Preventing Work-Related Musculoskeletal Disorders in Manufacturing by Digital Human Modeling

“…Among applications concerned with manufacturing, a wide variety of positions were investigated. For example, Grobelny et al [ 65 ] examined painters, fitters, polishers, pressers, technicians, forklift truck operators, and stockroom deliverers; Schall et al [ 66 ] focused on manual material handling by means of transfer carts and performing tasks such as window and door construction; Peruzzini et al [ 67 ] examined pipe external and internal grinding, cleaning, ovalization control, whereas Zhang et al [ 68 ] investigated welders. Studies directly involving assembly works were conducted, among others, by [ 69 , 70 , 71 ].…”

Ergonomic Rationalization Sequence of Digital Lighting Design in the Working Environment

“…In the field of the application of ergonomic simulation tools for the comprehensive assessment of the physical load of workers, there is an important article by Zhang et al [ 1 ], who deals with the ergonomic rationalization of welders’ standing postures. The authors created six digital welders using Jack human software, on which they implemented basic ergonomic methods for physical load assessment and determined the most suitable posture–operating distance, operating height, and rotation angle of the welder’s neck, in order to improve welders’ operational posture and prevent fatigue and injury to the welder.…”