0
TECHNICAL PAPERS

Tolerance Analysis of Free-Form Surfaces in Composite Material

[+] Author and Article Information
Wilma Polini1

Dipartimento di Ingegneria Industriale, Università degli Studi di Cassino, via G. di Biasio 43, 03043 Cassino, Italypolini@unicas.it, www.unicas.it

M. Marrocu

 Università degli Studi de Cassino, 03043 Cassino, Italy

L. D’Ambrosio

 AGUSTA Westland SpA, Aerospace Composites Center, 03012 Anagni, Italy

1

Corresponding author.

J. Comput. Inf. Sci. Eng 7(1), 31-43 (Jul 19, 2006) (13 pages) doi:10.1115/1.2424243 History: Received September 19, 2005; Revised July 19, 2006

The aim of this work is to present a method for the tolerance analysis of an assembly involving free-form surfaces based on dimensional and geometric tolerances. The great effort of the present work is to deal with dimensional and geometric tolerances applied to free-form surfaces. The case of study is the flaperon, a structural component of the aircraft, that is constituted by one skin cover, eight ribs, and one spar. The ten components of the flaperon are connected by adhesive, in order to overcome the problems due to the rivets use. Adhesive thickness between the faced parts to connect should be as constant as possible in order to obtain the right structural connection. The influence of the tolerances applied to the ten components of the flaperon on the value of the gap at the interfaces among each couple of components has been deeply investigated by means of the proposed method. Moreover, the influence of the tolerances on the aerodynamic performances of the flaperon has also been analyzed.

Copyright © 2007 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 2

(a) Flap function; and (b) Aleiron function

Grahic Jump Location
Figure 3

Tolerances applied to skin (datum C is the plane of the drawing)

Grahic Jump Location
Figure 4

Tolerances applied to a rib (datum C is the plane of the drawing)

Grahic Jump Location
Figure 5

Tolerances applied to spar (datum C is the plane of the drawing)

Grahic Jump Location
Figure 6

Interference and nonuniform gap between two faced surfaces

Grahic Jump Location
Figure 7

S1–S5 adhesive gaps

Grahic Jump Location
Figure 8

Assembly sequence of flaperon: (a) insertion of skin inside its fixture; (b) coupling of ribs with skin; and (c) positioning of spar

Grahic Jump Location
Figure 9

Skin deviations from nominal: T1 and A1

Grahic Jump Location
Figure 10

Rib deviations from nominal: T2, T3, and A2

Grahic Jump Location
Figure 11

Spar deviations from nominal: T4, T5, and T6

Grahic Jump Location
Figure 12

Stall conditions of flaperon aerodynamic surfaces

Grahic Jump Location
Figure 14

Scheme to calculate the minimum distance in A and C points

Grahic Jump Location
Figure 15

Control points on rib’s surface faced to spar (S3 gap)

Grahic Jump Location
Figure 16

Control points on spar’s surfaces faced to rib (S3) and to skin (S4 and S5 gaps)

Grahic Jump Location
Figure 17

(a) Absolute twist angle of a rib; and (b) calculation of absolute twist on the plane Z-Y

Grahic Jump Location
Figure 18

Waviness of a curve

Grahic Jump Location
Figure 19

To estimate flaperon waviness

Grahic Jump Location
Figure 20

Ranges including 99.73% of the distributions of the distance of all the couples of points of S1 gap: (a) worst case; and (b) nominal case

Grahic Jump Location
Figure 21

Ranges including 99.73% of the distributions of the distance of all the couples of points of S2 gap: (a) worst case; and (b) nominal case

Grahic Jump Location
Figure 22

Ranges including 99.73% of the distributions of the distance of all the couples of points of S3 gap: (a) worst case; and (b) nominal case

Grahic Jump Location
Figure 23

Ranges including 99.73% of the distributions of the distance of all the couples of points of S4 gap: (a) worst case; and (b) nominal case

Grahic Jump Location
Figure 24

Ranges including 99.73% of the distributions of the distance of all the couples of points of S5 gap: (a) worst case; and (b) nominal case

Grahic Jump Location
Figure 25

Results of sensitivity analysis on adhesive gaps

Grahic Jump Location
Figure 26

Ranges including 99.73% of the distributions of the absolute twist angle

Grahic Jump Location
Figure 1

(a) Flaperon exploded structure; and (b) flaperon datum reference system

Grahic Jump Location
Figure 13

Control points on rib’s surfaces faced to skin (S1 and S2 gaps)

Tables

Errata

Discussions

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