A Simplified Analytical/Experimental Method for Evaluating Large
Buses and Motor Coaches for Rollover Protection 2018-01-5033
This paper discusses a simplified analytical/experimental method for evaluating
and designing large buses and motor coaches for rollover protection. The
proposed method makes use of the work-energy principle in analyzing the
energy-absorbing capacity of the roof and sidewall structure of the vehicle. The
basic structural unit is treated as a nonlinear, elastoplastic, 4-bar linkage,
with the links connected at hinge points. During rollover, the deformation of
the structure is focused at these hinge points and energy absorption is achieved
through plastic bending and rotation of the hinge material. The proposed method
allows the evaluation and design of these plastic hinges to achieve the
energy-absorbing requirements for the vehicle. This paper demonstrates the
proposed methodology by evaluating an exemplar large bus design against the
European ECE-R.66 rollover design standard. This same vehicle was similarly
evaluated in a referenced study, using the finite element analysis (FEA) method.
The objective of both studies was to determine a minimum weight solution for the
vehicle structure. The minimum weight solution must satisfy both the minimum
energy absorption requirements and the structural deformation limitations placed
on the design by the ECE-R.66 standard. Both a baseline design and an optimized
(minimum weight) design were evaluated in this study. The baseline design served
as a reference point in determining the weight-saving potential for the vehicle.
The FEA results show a weight-saving potential of 78 kg (172 lb) while the
simplified, 4-bar linkage model gives a slightly heavier design with a
weight-saving potential of 34 kg (77 lb), indicating that the proposed method of
analysis is slightly conservative compared to the FEA method.
Citation: Pauls, L., "A Simplified Analytical/Experimental Method for Evaluating Large Buses and Motor Coaches for Rollover Protection," SAE Technical Paper 2018-01-5033, 2018, https://doi.org/10.4271/2018-01-5033. Download Citation
Author(s):
Lonney S. Pauls
Affiliated:
Springwater Micro Data Systems
Pages: 9
Event:
Automotive Technical Papers
ISSN:
0148-7191
e-ISSN:
2688-3627
Related Topics:
Finite element analysis
Design processes
Rollover accidents
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