Optimization of a Vehicle Space Frame Under Ballistic Impact Loading

2007 ◽  
Author(s):  
Umakanth Sakaray ◽  
Mohamed B. Trabia ◽  
Brendan J. O’Toole ◽  
Jagadeep Thota
Keyword(s):  
Impact Loading ◽  
Structural Integrity ◽  
Element Model ◽  
Stress Constraints ◽  
Frame Structure ◽  
Mass Reduction ◽  
Electronic Components ◽  
Space Frame ◽  
Military Vehicle ◽  
Joint Location

Shock from impact loading may risk the lives of the occupants of a military vehicle and damage the sensitive electronic components within it. A finite element model (FEM) for a space-frame based military vehicle is presented in this paper. An approach is developed to optimize the design of the joints within the space frame structure to reduce the mass of the vehicle while maintaining its structural integrity. The process starts by creating a parametric FEM of the vehicle. The optimization variables are the lengths of joint branches. The effect of joint location within the space frame is also explored. The problem is subject to geometry and stress constraints. Results show that a mass reduction can be achieved without adversely affecting integrity of the vehicle.

The Application of Slip Joint Use in Space Frame Structure for Vehicle

2013 ◽  
Vol 423-426 ◽  
pp. 1944-1947
Author(s):  
Sheng Yun Lee ◽  
Ting Hao Cheng ◽  
Yu Ting Lin
Keyword(s):  
Dimensional Accuracy ◽  
Element Model ◽  
Frame Structure ◽  
Poor Control ◽  
Space Frame ◽  
Space Frames ◽  
The Common ◽  
The Finite Element Model ◽  
Joint Method ◽  
Space Frame Structure

The purpose of this paper is to analysis the finite element model of joint methods for chassis space frames of vehicles. Common tee-joint often have poor control of dimensional accuracy. The analysis includes the common tee-joint and new joint method. Although the new joint method will increase in weight a little and easily adjust the accuracy of space frame, it will also improve the connection strength.

Optimization of the Shock Mitigation Layer in the Space Frame Joints of an Armored Vehicle

2013 ◽  
Author(s):  
Jagadeep Thota ◽  
Mohamed Trabia ◽  
Brendan O’Toole ◽  
Chang-Hyun Lee ◽  
Hong-Lae Park ◽  
...  
Keyword(s):  
Structural Integrity ◽  
Random Search ◽  
Quadratic Approximation ◽  
Frame Structure ◽  
Optimization Process ◽  
Internal Space ◽  
Space Frame ◽  
Beam Elements ◽  
Shock Mitigation ◽  
Armored Vehicle

Armored vehicles have to survive multiple threats such as projectile or land mines. The shocks induced by these threats can harm vehicle occupants or damage sensitive electronic components. Therefore, a goal of modern armored vehicle design is to reduce transmitted shocks to critical components. In this paper, finite element (FE) models of an armored vehicle prototype having the internal space frame structure with the aforementioned features are developed. One model comprises of only solid elements, while another model is created with purely beam elements. The beam elements model is used for optimization studies whose objective is to reduce the shocks within the vehicle, due to mine blast while maintaining its overall structural integrity. The thickness of the rubberized shock mitigation layer at the joints of the space frame is varied during the optimization process. The optimization problem is solved using the Successive Heuristic Quadratic Approximation (SHQA) algorithm, which combines successive quadratic approximation with an adaptive random search while varying the bounds of the search space. The entire optimization process is carried out within the MATLAB environment. The results show that a significant reduction in the shock can be achieved using this approach.

Optimization of a Military Vehicle Space Frame Subject to High Impact Loading

2008 ◽  
Author(s):  
Jagadeep Thota ◽  
Mohamed B. Trabia ◽  
Brendan J. O’Toole
Keyword(s):  
Structural Integrity ◽  
Impact Load ◽  
Random Search ◽  
Element Model ◽  
Search Space ◽  
High Impact ◽  
Quadratic Approximation ◽  
Space Frame ◽  
Cross Sectional ◽  
Space Frames

Space frames are usually used to enhance structural strength of the vehicle while reducing its overall weight. These frames are comprised of beams connected together at joints. Recently, space frames are incorporated in military vehicles. However, space frames in this case are subjected to different types of loading than what is encountered in civilian vehicles such as, projectile and land mine attacks. In this paper, a finite element model for the upper half of the space frame of an armored vehicle is developed. The space frame is composed of hollow square cross-section bars and angle sections and is enclosed by uniform-thickness armor, except at the turret. The vehicle is subjected to high impact load that simulates an impact of a projectile. The model is parameterized to minimize the mass of the space frame and vehicle armor by varying the cross-sectional parameters of the beam members and joints, and the thickness of the armor plate, while maintaining the overall structural integrity of the space frame. This problem is solved using the Successive Heuristic Quadratic Approximation (SHQA). This algorithm combines successive quadratic approximation with an adaptive random search within varying search space. The entire optimization process is carried out within MATLAB environment. Results show significant reduction of the mass of the vehicle.

Simulation of Shock Response in a Lab-Scale Space Frame Structure Using Finite Element Analysis

2011 ◽  
Author(s):  
Jagadeep Thota ◽  
Mohamed B. Trabia ◽  
Brendan J. O’Toole
Keyword(s):  
Finite Element ◽  
Impact Loading ◽  
Scale Space ◽  
Frame Structure ◽  
Frame Structures ◽  
Fe Model ◽  
Space Frame ◽  
Element Analysis ◽  
Acceleration Signals ◽  
Space Frame Structure

Space frames are usually used to enhance the structural strength of a vehicle while reducing its overall weight. Impact loading is a critical factor when assessing the functionality of these frames. In order to properly design the space frame structure, it is important to predict the shocks moving through the members of the space frame. While performance of space frame structures under static loads in well-understood, research on space frame structures subjected to impact loading is minimal. In this research, a lab-scale space frame structure, comprising of hollow square members that are connected together through bolted joints which allow for quick assembly/disassembly of a particular section, is manufactured. Non-destructive impact tests are carried out on this space frame structure and the resulting acceleration signals at various locations are recorded. A finite element (FE) model of the lab-scale structure is created and simulated for the experimental impact loads. Acceleration signals from the FE model are compared with the experimental data. The natural frequencies of the structure are also compared with the results of the FE model. The results show a good match between the model and the experimental setup.

Creep-Fatigue Interaction Effects On Pressure-Reducing Valve Under Cyclic Thermo-Mechanical Loadings Using Direct Cyclic Method

2021 ◽  
Author(s):  
Nak-Kyun Cho ◽  
Youngjae Choi ◽  
Haofeng Chen
Keyword(s):  
High Temperature ◽  
Power Plant ◽  
Fatigue Failure ◽  
Material Properties ◽  
Structural Integrity ◽  
Direct Method ◽  
Element Model ◽  
Critical Loading ◽  
Creep Fatigue ◽  
Pressure Reducing Valve

Abstract Supercritical boiler system has been widely used to increase efficiency of electricity generation in power plant industries. However, the supercritical operating condition can seriously affect structural integrity of power plant components due to high temperature that causes degradation of material properties. Pressure reducing valve is an important component being employed within a main steam line of the supercritical boiler, which occasionally thermal-fatigue failure being reported. This research has investigated creep-cyclic plastic behaviour of the pressure reducing valve under combined thermo-mechanical loading using a numerical direct method known as extended Direct Steady Cyclic Analysis of the Linear Matching Method Framework (LMM eDSCA). Finite element model of the pressure-reducing valve is created based on a practical valve dimension and temperature-dependent material properties are applied for the numerical analysis. The simulation results demonstrate a critical loading component that attributes creep-fatigue failure of the valve. Parametric studies confirm the effects of magnitude of the critical loading component on creep deformation and total deformation per loading cycle. With these comprehensive numerical results, this research provides engineer with an insight into the failure mechanism of the pressure-reducing valve at high temperature.

Dynamic Impact Measurements on Crossings, in Free Floating and In-Situ Conditions

2014 ◽  
Author(s):  
M. A. Boogaard ◽  
A. L. Schwab ◽  
Z. Li
Keyword(s):  
Finite Element ◽  
Condition Monitoring ◽  
Impact Loading ◽  
Dynamic Behaviour ◽  
Element Model ◽  
Mode Shapes ◽  
Dynamic Impact ◽  
In Situ Test ◽  
In Situ Conditions

As vibration based condition monitoring requires a good understanding of the dynamic behaviour of the structure, a good model is needed. At the TU Delft a train borne monitoring system is being developed which currently focusses on crossings. Crossings are prone to very fast degradation due to impact loading. In this paper a finite element model of a free floating frog is presented and validated up to a 100 Hz using dynamic impact measurements. The mode shapes of the free floating frog are then also compared to some preliminary results from an in-situ test. This comparison shows that the in-situ frequencies can be up to twice the free floating frequency.

scholarly journals Mechanical Strength Study of a Cranial Implant Using Computational Tools

2022 ◽  
Vol 12 (2) ◽  
pp. 878
Author(s):  
Pedro O. Santos ◽  
Gustavo P. Carmo ◽  
Ricardo J. Alves de Sousa ◽  
Fábio A. O. Fernandes ◽  
Mariusz Ptak
Keyword(s):  
Structural Integrity ◽  
Mechanical Performance ◽  
Skull Fracture ◽  
Human Head ◽  
Element Model ◽  
Von Mises Stress ◽  
Cranial Implant ◽  
Von Mises ◽  
Two Parameters ◽  
The Brain

The human head is sometimes subjected to impact loads that lead to skull fracture or other injuries that require the removal of part of the skull, which is called craniectomy. Consequently, the removed portion is replaced using autologous bone or alloplastic material. The aim of this work is to develop a cranial implant to fulfil a defect created on the skull and then study its mechanical performance by integrating it on a human head finite element model. The material chosen for the implant was PEEK, a thermoplastic polymer that has been recently used in cranioplasty. A6 numerical model head coupled with an implant was subjected to analysis to evaluate two parameters: the number of fixation screws that enhance the performance and ensure the structural integrity of the implant, and the implant’s capacity to protect the brain compared to the integral skull. The main findings point to the fact that, among all tested configurations of screws, the model with eight screws presents better performance when considering the von Mises stress field and the displacement field on the interface between the implant and the skull. Additionally, under the specific analyzed conditions, it is observable that the model with the implant offers more efficient brain protection when compared with the model with the integral skull.

Finite-Element Model of Impact Loading and Deformation of a Flexible Steel Ring-Net Debris-Flow Barrier

2020 ◽  
Vol 21 (3) ◽  
pp. 04020026
Author(s):  
Aliena M. Debelak ◽  
Christopher A. Bareither ◽  
Hussam Mahmoud
Keyword(s):  
Finite Element ◽  
Debris Flow ◽  
Finite Element Model ◽  
Impact Loading ◽  
Element Model ◽  
Ring Net
Sign in / Sign up

Export Citation Format

Share Document