Variation propagation modeling and analysis of automotive body outer cover panels assembly systems. Issue 2 (1st April 2019)

• Record Type: Journal Article
• Authors: Han, Wenwu; Deng, Qianwang; Lin, Wenhui; Gong, Xuran; Ding, Sun
• Is Part Of: Assembly automation. Volume 39:Issue 2(2019)
• Page Start: 272
• Page End: 286
• Publication Date: 2019-04-01
• Subjects: Quality control -- Compliant mechanisms -- Simulation -- Assembly -- Variation propagation -- State space modelling; Automation -- Periodicals; Automatic machinery -- Periodicals; Assembly-line methods -- Periodicals; Industrial engineering -- Periodicals; 670.42705
• DOI: 10.1108/AA-05-2018-067
• Languages: English
• ISSNs: 0144-5154

Abstract

Abstract : Purpose: This study aims to present a model and analysis of automotive body outer cover panels (OCPs) assembly systems to predict assembly variation. In the automotive industry, the OCPs assembly process directly influences the quality of the automobile body appearance. However, suitable models to describe variation propagation of OCPs assembly systems remain unknown. Design/methodology/approach: An adaptive state space model for OCPs assembly systems is introduced to accurately express variation propagation, including variation accumulation and transition, where two compliant deviations make impacts on key product characteristics (KPCs) of OCP, and the impacts are accumulated from welding process to threaded connection process. Another new source of variation from threaded connection is included in this model. To quantify the influence of variation from threaded connection on variation propagation, the threaded connection sensitivity matrix is introduced to build up a linear relationship between deviation from threaded connection and output deviation in KPCs. This matrix is solved by homogeneous coordinate transformation. The final deviation of KPCs will be transferred to ensure gaps and flushes between two OCPs, and the transition matrix is considered as a unit matrix to build up the transition relationship between different states. Findings: A practical case on the left side body structure is described, where simulation result of variation propagation reveals the basic rule of variation propagation and the significant effect of variation from threaded connection on variation propagation of OCPs assembly system. Originality/value: The model can be used to predict assembly variation or potential dimension problems at a preliminary assembly phase. The calculated results of assembly variation guide designers or technicians on tolerance allocation, fixture layout design and process planning.