scholarly journals Methods for absorbing kinetic energy with consideration of delay limit value

2021 ◽  
Vol 334 ◽  
pp. 01006
Author(s):  
Jarosław Rajczyk ◽  
Marlena Rajczyk ◽  
Jarosław Kalinowski ◽  
Budownictwa Wydział
Keyword(s):  
Kinetic Energy ◽  
Energy Absorption ◽  
The Body ◽  
Limit Value ◽  
Energy Absorbers ◽  
Energy Absorbing

In this paper the potential of kinetic energy absorption by means of energy absorbing and storing mechanisms was discussed. The use of energy absorbers is intended to reduce the maximum working forces when stopping the body.

scholarly journals Reversed-torsion-type crush energy absorption structure and its inexpensive partial-heating torsion manufacturing method based on origami engineering

2021 ◽  
pp. 1-31
Author(s):  
Xilu Zhao ◽  
Chenghai Kong ◽  
Yang Yang ◽  
Ichiro Hagiwara
Keyword(s):  
Energy Absorption ◽  
Peak Load ◽  
Point Of View ◽  
Building Structures ◽  
Manufacturing Method ◽  
Partial Heating ◽  
Vehicle Structure ◽  
Energy Absorbers ◽  
Energy Absorbing ◽  
Origami Engineering

Abstract Current vehicle energy absorbers face two problems during a collision in that there is only a 70% collapse in length and there is a high initial peak load. These problems arise because the presently used energy-absorbing column is primitive from the point of view of origami. We developed a column called the Reversed Spiral Origami Structure (RSO), which solves the above two problems. However, in the case of existing technology of the RSO, the molding cost of hydroforming is too expensive for application to a real vehicle structure. We therefore conceive a new structure, named the Reversed Torsion Origami Structure (RTO), which has excellent energy absorption in simulation. We can thus develop a manufacturing system for the RTO cheaply. Excellent results are obtained in a physical experiment. The RTO can replace conventional energy absorbers and is expected to be widely used in not only automobile structures but also building structures.

Design of a Hybrid Lightweight Energy Absorber

2016 ◽  
Vol 713 ◽  
pp. 321-324
Author(s):  
A. de Luca ◽  
Giuseppe Lamanna ◽  
Raffaele Sepe ◽  
Alessandro Soprano
Keyword(s):  
Kinetic Energy ◽  
Numerical Investigation ◽  
Structural Design ◽  
Carbon Composite ◽  
Energy Absorber ◽  
Load Paths ◽  
Passenger Safety ◽  
Carbon Composite Materials ◽  
Energy Absorbers ◽  
Energy Absorbing

Among several problems which might affect the passenger safety during an accidental crash event, the deceleration pulse is one of the most critical. For this reason vehicles are designed to convert the Kinetic Energy occurring in an impact in plastic deformation and to spread the loads due to such events through designed structural load paths. An important role in the kinetic energy absorbing at high velocities is played by the energy absorbers. The energy absorption capability of a crashworthy element or system is largely affected by material properties and structural design. This work deals with a numerical investigation on the energy absorbing capability of a new concept of energy absorber made out of the combination of metal parts and carbon composite materials. A numerical investigation on the parameters which increase the crash performance as well as decrease the weight of such device has been presented in this paper.

Key Performance Indicators of Tubes Used as Energy Absorbers

2014 ◽  
Vol 626 ◽  
pp. 155-161 ◽  
Author(s):  
T.X. Yu ◽  
Yan Fei Xiang ◽  
Min Wang ◽  
Li Ming Yang
Keyword(s):  
Energy Absorption ◽  
Carrying Capacity ◽  
Performance Indicators ◽  
Key Performance Indicators ◽  
Absorption Capacity ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Engineering Designs ◽  
Energy Absorbers ◽  
Energy Absorbing

Based on our extensive studies on the experimental, theoretical and numerical results on various tubes under axial compression/impact in the last few years, we propose a set of Key Performance Indicators (KPIs) to assess and compare the energy absorbing performance of tubular structures with various configurations, so as to guide the design of energy absorbers whilst to archive a certain degree of optimization. The KPIs have five factors: Effective stroke ratio (ESR), Non-dimensional Load-carrying capacity (NLC), Effectiveness of energy absorption (EEA), Specific energy absorption capacity (SEA), Stableness of load-carrying capacity (SLC).The paper presents a series of diagrams to compare the energy absorbing performance of various tubes in terms of the four KPIs as described above. The work is valuable to engineering designs and applications, as well as to the further studies of the topic.

Key Performance Indicators of Tubes and Foam-Filled Tubes Used as Energy Absorbers

2015 ◽  
Vol 07 (04) ◽  
pp. 1550060 ◽  
Author(s):  
Yanfei Xiang ◽  
Min Wang ◽  
Tongxi Yu ◽  
Liming Yang
Keyword(s):  
Energy Absorption ◽  
Carrying Capacity ◽  
Performance Indicators ◽  
Key Performance Indicators ◽  
Load Carrying Capacity ◽  
Tubular Structures ◽  
Load Carrying ◽  
Foam Filled ◽  
Energy Absorbers ◽  
Energy Absorbing

Based on a systematic investigation on the experimental, theoretical and numerical results on various tubes under axial compression/impact including our own tests, a set of key performance indicators (KPIs) for assessing and comparing the energy absorbing performance of tubular structures with various configurations is proposed, so as to guide the design of energy absorbers whilst to facilitate parameter optimization. The five KPIs proposed on the basis of mechanical analyses are effective stroke ratio (ESR), nondimensional load-carrying capacity (NLC), specific energy absorption (SEA), effectiveness of energy absorption (EEA) and undulation of load-carrying capacity (ULC). Moreover, by considering the influence of foam filling, these five KPIs are also modified and extended to the foam-filled tubes. The paper presents a series of diagrams to compare the energy absorbing performance of various tubes in terms of the five KPIs as described above. It transpires that the energy absorption performance of circular tubes is superior to that of square tubes. It is also confirmed that the mass of foam fillers results in reductions of SEA and EEA, though foam fillers will greatly improve the NLC of empty tubes. The novelty of the present study is displayed on the following aspects: (1) uniquely defining the effective stroke by the maximum point of "energy efficiency" f so as to avoid ambiguity which appeared in the literature; (2) instead of a single indicator such as SEA, proposing a set of five KPIs to comprehensively assess the performance of energy absorbers and (3) validating the usefulness of the proposed KPIs by comparing the performance of various tubular structures used as energy absorbers.

scholarly journals Characteristics of Rectangular Section and Double Hat Section

2019 ◽  
Vol 9 (2S4) ◽  
pp. 457-460
Keyword(s):  
Energy Absorption ◽  
Testing Machine ◽  
Primary Objective ◽  
Rectangular Section ◽  
Universal Testing ◽  
Collapse Mode ◽  
Post Test ◽  
The Difference ◽  
Energy Absorbers ◽  
Energy Absorbing

This proposal defines the difference between the double hat section tubes &rectangular section for tremble energy consumption like in crash worth applications. The primary objective of this study is to “to gather information regarding the energy absorption & impact of double and single cap section tubes and to apply them in the system where energy absorption takes place.The double-hat and thin-walled top-hat in which spot-welded by quasi-static axial method. Many tests were identified such as associated energy-absorbing characteristics and several post-test collapse mode where scrutinized and compared with other previous tests. The best model was selected by crush analysis in universal testing machine by comparison of parameters such as mean force and energy absorbers. The efficient model is selected by comparatively lesser mean force and higher energy absorption

scholarly journals Mechanisms of energy absorption in special devices for use in earthquake resistant structures

1972 ◽  
Vol 5 (3) ◽  
pp. 63-88 ◽  
Author(s):  
J. M. Kelly ◽  
R. I. Skinner ◽  
A. J. Heine
Keyword(s):  
Reinforced Concrete ◽  
Kinetic Energy ◽  
Mild Steel ◽  
Energy Absorption ◽  
Earthquake Engineering ◽  
Absorption Capacity ◽  
Concrete Frames ◽  
Energy Absorption Capacity ◽  
Structural Applications ◽  
Energy Absorbing

A structure designed to resist earthquake attack must have a capacity to dissipate kinetic energy induced by the ground motion. In most structures this energy absorption is developed in the vicinity of beam to column connections. Recent research has shown that connections are not reliable when subject to cyclic loading, such as results from earthquake attack. Connections in steel frames deteriorate due to local instabilities in adjacent flanges, and in reinforced concrete frames alternating shear
loads produce diagonal tension and bond failures which progressively reduce the strength of the connection. Much work in building research and earthquake engineering in laboratories throughout the world is directed toward increasing the reliability and energy absorption capacity of structural connections. In this paper an alternative approach to this problem is described. This approach is to separate the load carrying function of the structure from the energy absorbing function and to ask if special devices could be incorporated into the structure with the sole purpose of absorbing the kinetic energy generated in the structure by earthquake attack. To determine whether such devices are feasible a study has been undertaken of three essentially different mechanisms of energy absorption. These mechanisms all utilized the plastic deformation of mild steel. They included the rolling of strips, torsion of square and rectangular bars,
 and the flexure of short thick beams. These mechanisms were selected for intensive study since they were basic to three different types of device each of which was designed for a separate mode of operation in a structural system. The characteristics of these mechanisms which were of primary importance in this study were the load displacement relations, the energy absorption capacity and the fatigue resistance. This information was obtained with a view to the development of devices for specific structural applications. This report describes the tests used to explore the basic mechanisms and the data obtained. It also include s a brief description of tests on scale models of a device which was designed to be located in the piers of a reinforced concrete railway bridge. It has been shown by the tests that the plastic torsion of mild steel is an extremely efficient mechanism for the absorption of energy. It was found that at plastic strains in the range 3% to 12% it was possible to develop energy dissipation of the order of 2000-7500 lb in/in3 per cycle (14-50 x 106 N/M2 per cycle) with lifetimes within the range of 1000 to 100 cycles. It was also shown that the mode of failure in torsion is an extremely favourable one for use in an energy absorbing device in that it took the form of a gradual decay. The other two mechanisms studied were both less efficient and less reliable than torsion and had capacities of 500-2000 lb in/in3 per cycle (3.5 - 14 x 106 N/M2 per cycle) and life times of around 200 to 20 cycles. Nevertheless they lend themselves to more compact devices than does the torsional mechanism and furthermore the devices may be located in regions in a structure where they are readily accessible for replacement after attack.

scholarly journals Forensic Analysis Of Low Speed Vehicle Collisions

2003 ◽  
Vol 20 (1) ◽  
Author(s):  
John A. DOnofrio
Keyword(s):  
Kinetic Energy ◽  
Forensic Analysis ◽  
The Body ◽  
Conservation Of Energy ◽  
Low Speed ◽  
Stop Sign ◽  
Post Impact ◽  
Energy Dissipated ◽  
Energy Absorbing ◽  
Crash Tests

A Low Speed Collision Is Defined, For The Purpose Of This Paper, As A Collision Between Two Vehicles That Produces No Permanent Damage To The Body Of The Vehicle Except To The Bumper System. The Vehicles Are Equipped With Energy Absorbing Bumpers That Are Rated To A Particular Speed. The Collisions Are, For All Intents And Purposes, In-Line In Nature (Collinear) And Without Post-Impact Rotation. This Definition, While Quite Specific, Covers A Large Number Of Collisions. They Are The Typical Stop Sign, Waiting In Traffic, Parking Lot Type Crash. In The Following Sections I Will Examine How These Vehicles Interact And Respond To Such Collisions By Applying Newtons Laws And The Data From Vehicle Crash Tests. Presented Is Methodology For Reconstructing The Pre-Impact And Post-Impact Speed Of Such Collisions Using The Following Protocol: 1. Compute The Kinetic Energy Dissipated In The Collision From The Characteristics Of The Vehicles And Their Bumpers As Revealed In Crash Tests. 2. Use Conservation Of Energy And Damage Relationships To Determine The Pre-Collision Kinetic Energy And Closing Speed Of The Two-Vehicle System. 3. Use Conservation Of Linear Momentum To Calculate The Post-Collision Speed And Delta-V Of The Two Vehicles. This Method Uses The Strict Application Of Newtons Laws And Treats Both Vehicles As A System.

A Numerical and Experimental Study on the Energy Absorption Characteristics of Deployable Origami Tubes

2021 ◽  
Author(s):  
Zhongyuan Wo ◽  
Julia M. Raneses ◽  
Evgueni T. Filipov
Keyword(s):  
Energy Absorption ◽  
Experimental Studies ◽  
Crushing Force ◽  
Parametric Studies ◽  
Energy Absorbers ◽  
Collapse Behavior ◽  
Energy Absorbing ◽  
Impact Characteristics ◽  
Absorption Characteristics ◽  
Better Than

Abstract Energy absorption devices are widely used to mitigate damage from collisions and impact loads. Due to the inherent uncertainty of possible impact characteristics, passive energy absorbers with fixed mechanical properties are not capable of serving in versatile application scenarios. Here, we explore a deployable design concept where origami tubes can extend, lock, and are intended to absorb energy through crushing (buckling and plasticity). This system concept is unique because origami deployment can increase the crushing distance between two impacting bodies and can tune the energy absorption characteristics. We show that the stiffness, peak crushing force, and total energy absorption of the origami tubes all increase with the deployed state. We present numerical and experimental studies that investigate these tunable behaviors under both static and dynamic scenarios. The energy-absorbing performance of the deployed origami tubes is slightly better than conventional prismatic tubes in terms of total absorbed energy and peak force. When the origami tubes are only partially deployed, they exhibit a nearly-elastic collapse behavior, however, when they are locked in a more deployed configuration they can experience non-recoverable crushing with higher energy absorption. Parametric studies reveal that the geometric design of the tube can control the nonlinear relationship between energy absorption and deployment. This concept for deployable energy-absorbing origami tubes can enable future protective systems with on-demand properties for different impact scenarios.

scholarly journals The Effect of Geometrical Non-Linearity on the Crashworthiness of Thin-Walled Conical Energy-Absorbers

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4857
Author(s):  
Michal Rogala ◽  
Jakub Gajewski ◽  
Miroslaw Ferdynus
Keyword(s):  
Energy Absorption ◽  
Wall Thickness ◽  
Absorption Capacity ◽  
Energy Absorption Capacity ◽  
Cross Sectional ◽  
Variable Wall Thickness ◽  
Thin Walled ◽  
Variable Wall ◽  
Energy Absorbers ◽  
Energy Absorbing

Crashworthiness of conical shells is known to depend on various factors. This study sets out to determine the extent to which the cross-sectional diameter contributes to their energy-absorbing properties. The object of the study was thin-walled aluminium tubes varying in upper diameter and wall thickness. The components were subjected to dynamic axial crushing kinetic energy equal to 1700 J. The numerical analysis was performed using Abaqus 6.14 software. The specific aim of the study was to determine the extent to which variable wall thickness affects the energy absorption capacity of the components under study. From the simulations, we have managed to establish a relationship between total energy absorption capacity and wall thickness. The results from the conducted analyses and the purpose-specific neural networks could provide the base for the future methodology for forecasting and optimisation of energy-absorbing systems.

Investigation of Energy Absorption Behaviour of Square Aluminium Tubes with Cutouts under Axial Compression

2019 ◽  
Vol 969 ◽  
pp. 181-186
Author(s):  
L. Prince Jeya Lal ◽  
G. Yuvaraj ◽  
S. Ramesh
Keyword(s):  
Energy Absorption ◽  
Axial Compression ◽  
Progressive Collapse ◽  
Research Work ◽  
Peak Load ◽  
Compressive Force ◽  
Triggering Mechanisms ◽  
Energy Absorbers ◽  
Energy Absorbing ◽  
Passenger Cabin

Energy absorbers in the form of hollow profiles are used in automobiles to mitigate energy transfer to passenger cabin during a crash event. A similar event is carried out in this research work to study the progressive compression behaviour of aluminium tubes with triggering mechanisms in the form of cut-outs. Various hollow profiles are used as energy absorbing elements. In this work, square aluminium tubes of 50x50 mm side and 150 mm length with wall thickness of 1.5 mm with cut-outs are tested under axial compression loading and the results are compared with tubes without any cutouts. Crash parameters like minimum compressive force required to fail the aluminium tube, energy absorption, peak load and progressive collapse behaviour are studied. Results reveal that tubes with slots exhibited better crash parameters than plain tubes and tubes with circular cutouts.

Sign in / Sign up

Export Citation Format

Share Document