IJPEM
Precision assembly simulation of skin model shapes accounting for contact deformation
and geometric deviations for statistical tolerance analysis method
Songhua Ma/Shandong University
-
Keywords : Tolerance analysis,
Skin model shape,
Local contact deformation,
Assembly simulation,
Geometric deviation
-
Tolerance analysis methods, which are important to achieve a balance between
manufacturing costs and functional requirements, have been studied and improved over
the last 30 years. This paper proposes a new method to improve the precision of
assembly simulation for statistical assembly simulation; by investigating the effect
of the geometric deviations and mechanical behaviors of assembly contact on the
stack-up assembly deviation by combining the recent theories on the tolerance
analysis of rigid bodies and local contact deformation. To improve the precision of
the tolerance analysis, real parts with form defects were simulated with the help of
non-nominal skin model shapes. The SMSs were first considered to be rigid, and a
quadratic optimization-based method for the rigid body displacement was used to
calculate the initial contact points of all the SMSs. Next, contact deformation,
following Hertzian contact theory, occurred at the initial contact points, which
changed the relative positions of the SMSs in the subsequent interactions. The
iteration process was convergent, and the final simulation for tolerance analysis
could be generated after several iterations. Case studies demonstrated the
practicality of the proposed method. Their actual assembly deviations were simulated
by combining the effects of geometric deviations and local surface deformations.
Since the proposed tolerance analysis framework based on statistical assembly
simulation, it is expected to control the functional requirements of mechanical
assemblies with much rough tolerance design and help optimize the tolerance in the
future.
메뉴열기
