Research Papers

Variation Analysis and Robust Fixture Design of a Flexible Fixturing System for Sheet Metal Assembly

[+] Author and Article Information
Bing Li, Hongjian Yu

Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, P. R. China

Xiaojun Yang1

Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055, P. R. Chinalibing.sgs@hit.edu.cn

Ying Hu

Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China; The Chinese University of Hong Kong, Hong Kong, P. R. China


Corresponding author.

J. Manuf. Sci. Eng 132(4), 041014 (Aug 03, 2010) (13 pages) doi:10.1115/1.4002033 History: Received October 27, 2008; Revised August 04, 2009; Published August 03, 2010; Online August 03, 2010

Flexibility of assembly systems is crucial to maintaining the competitiveness in the rapidly changing market. In this paper, a novel flexible fixturing system for sheet metal part assembly is presented, which utilizes parallel robots as reconfigurable fixture elements. The method of influence coefficients, combined with finite element analysis and screw theory, is used to analyze the variations in sheet metal assembly. In the analysis of assembly variations, a total of six variations involved in prewelding, underwelding, and afterwelding process are intensively considered. Screw theory is employed to model the kinematic and constraint features corresponding to the fixturing schemes. A robust fixture layout design model is developed based on the Lagrangian conditional extremum method. A case study illustrates that the robust optimal methodology and an optimal fixture layout scheme with less sensitivity can be obtained.

Copyright © 2010 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Figure 1

Diagram of serial assembly and parallel assembly: (a) assembly in-serial and (b) assembly in-parallel

Grahic Jump Location
Figure 2

Diagram of reconfigurable fixture based on parallel robot

Grahic Jump Location
Figure 3

Flexible fixturing system with 4-2-1 fixturing scheme composed of parallel robots: (a) 3D model and (b) schematic diagram

Grahic Jump Location
Figure 4

Illustrative diagram of parallel mechanisms used for flexible fixtures: (a) 3-UPU/UPU (3-DoF), (b) 3-UPU/UPS (4-DoF), and (c) 3-RUPR/UPS (4-DoF)

Grahic Jump Location
Figure 5

Illustrative diagram of inverse kinematics solution

Grahic Jump Location
Figure 6

Simulation of positional workspace of the three parallel mechanisms: (a) 3-UPU/UPU (3-DoF), (b) 3-UPU/UPS (4-DoF), and (c) 3-RUPR/UPS (4-DoF)

Grahic Jump Location
Figure 7

Flowchart of the variations in the assembly process

Grahic Jump Location
Figure 8

Illustrative diagram of welding variation

Grahic Jump Location
Figure 9

Diagram of the 2-1 locating scheme: (a) optimum setting of 2-1 scheme and (b) variation in 2-1 scheme

Grahic Jump Location
Figure 10

Diagram of different slot orientation arrangements

Grahic Jump Location
Figure 11

Diagram of the 4 locating scheme: (a) diagram of 4 locating scheme and (b) variations in four locating scheme

Grahic Jump Location
Figure 12

Diagram of square finite element model

Grahic Jump Location
Figure 13

Distribution map of assembly variation

Grahic Jump Location
Figure 14

Robust assembly fixture design of two sheet metal parts: (a) illustrative diagram of underbody assembly and (b) schematic plan of underbody assembly

Grahic Jump Location
Figure 15

Finite element model of sheet metal assembly



Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In