Investigating the need for a new standard/specification for DH and SuperG helmets.


 Judith Kelley
 2 years ago
 Views:
Transcription
1 Investigating the need for a new standard/specification for DH and SuperG helmets. By: Svein Kleiven and Peter Halldin Division of Neuronic Engineering, School of Technology and Health, Royal Institute of Technology, Stockholm, Sweden. Background The International Ski Federation (FIS) working group for technical equipment with Pernilla Wiberg as chairman asked for a recommendation if and how to make helmets safer for Downhill and SuperG. The reason is that several severe head injuries have occurred the last seasons. The helmets used today need to pass the EN 1077 test standard where the helmet is dropped vertically on a flat anvil at a speed of 5.4m/s. The pass fail criterion is a translational acceleration below 250G. The question is if this test results in helmets with the best possible head protection for the skier. FIS has therefor asked KTH (Royal Institute of Technology) together with NIH, Mavet and UIBK to evaluate the specification for the helmets used in high speed impacts in ski slopes prepared for Downhill or SuperG races. Goal Improve the helmet in order to reduce the number of injuries from Downhill and SuperG accidents. The project The project was initiated in August Here is first a short summary presented on the work conducted by KTH between August 2011 and March Then is the results presented conducted between April and May And finally is the plan for the future presented. Previous work August March 2012 TV footage from 11 accidents during has been collected by NIH, Oslo. Video analysis of the accidents has been conducted by KTH using the software Skillspector (Figure 1). The preliminary results show that impact speed in the gathered accidents are relative high compared to the velocities (5.4m/s) used in the current test standard. It is also shown that the impact angle is very steep (Around 20 degrees compared to current helmet standard where the impact angle is 90 degrees).
2 Figure 1 Left: Video analysis of Case F4. Right: Summary of preliminary impact speeds and impact angles in the accidents from FIS competitions between (Observe that the Mean values in the figure above are preliminary and not final). The next step was to use the head kinematics (vertical and horizontal linear velocity, rotational velocity and impact sited on the helmet) from the video analysis and then perform accidents reconstructions by use of the detailed KTH head model, Figure 2. The reason for the accident reconstruction was to evaluate if the steep impact angle is important to take into account when designing future helmets. Figure 2. Injury reconstruction from the video analysis. The input in this reconstruction is, except for the head kinematics, the FE model of the human head (Kleiven et al 2007), a model of a helmet validated against experimental tests at KTH and a FE model of the snow (Keller et al. 2004, Mössner 2011, Mellor 1977, Landauer Narita,
3 1980, Kirchner et al. 2001). The coefficient of friction was set to 0.1 representing dynamic dry friction for snow (Bowden Shimbo Barnes et al Evans et al Kuroiwa Colbeck and Glaciol. 1988). The initial results from reconstruction of three accidents showed that the rotational acceleration was very high for one of the accidents and quite low for two of the other accidents. Another study using just a FE model of a Hybrid III dummy head equipped with a helmet was conducted to analyze how the impact direction affected the results, Figure 3. It was found that the rotational acceleration transmitted to the head was very much depending on the stature of the skier, Figure 4. In the analysis was the impact speeds taken from the video analysis from the case F4. It was shown that the rotational acceleration in the head was around 5000 radians/s 2 for the Rear impact while radians/s 2 for the frontal impact as defined in Figure 4. It was a bit surprising that the rotational acceleration was as high as the coefficient of friction is so low as 0.1 for dry snow. The FE studies raised questions if the rotational accelerations and the rotational energy seen in the head could be caused by the tangential force from the snow or caused by offset impacts (impacts where the CG (center of gravity) of the head in the impact is offset the impact point on the helmet causing the rotation by the CG moment arm). So, the initial work did not lead to any conclusion but to questions. The first question to answer in order to believe in the results is how relevant the snow data from the literature data is for a modern DH and SuperG ski slope. It was therefore decided to validate the boundaries used in the simulations further. The most important boundary is the snow properties and the contact definition to the snow including the coefficient of friction. Figure 3 Showing the Linear horizontal (Vh) and Vertical (Vv) velocities and the rotational velocity applied on the FE model of the Hybrid III head and helmet.
4 Figure 4 Shows different impact directions analyzed. Recent work April May 2012 The project is now divided into the following tasks. Phase 1  Experiment of helmet impact on hard snow, Åre Sweden (Done). Phase 2  Simulation of snow impact (Almost done). Verification of snow/ice stiffness Verification of coefficient of friction Phase 3  Video analyze real accidents Definition of impact speed and impact angle in a typical accident. (Partly done) Phase 4  Reconstruction of the accident by use of a detailed FE model of the human head and brain (Kleiven 2007). Correlation to medical pictures. (Partly done) Phase 5  Conclusion and recommendation on how a DH and Superg helmet test standard should be designed. Phase 1 and 2 were added in the project in order to perform experiments on site in a ski slope prepared for competition. Experimental tests have been performed in Åre, Sweden (March 2012). A Hybrid III dummy head including accelerometers was equipped with ski helmets (RED Force). The helmet was chosen as it has a smooth outer surface of the shell, which is the case with a normal competition helmet. Acceleration data was collected from the tests and all tests was filmed with a high speed camera (600 fps). The helmets were dropped from 1.7m resulting in an impact speed of 5.8 m/s, Figure 5.
5 Figure 5. Photos from the experimental set up in Åre, Sweden. The experimental test was then compared to a FE model (Figure 6) in order to: 1. Validate the snow model by measuring the intrusion from the helmet in the snow. 2. Verify the coefficient of friction between the helmet and the snow. The results from this study will be presented in a separate report. In short, the findings are: 1. That the snow model that has been used so far is too stiff and produce linear accelerations that are around 50% too high compared to tests on real snow. New constitutive models and material properties are currently being evaluated. 2. A coefficient of friction of around 0.1 shows the best correlation so far. The final verification will be made when a new constitutive model for snow is validated. Figure 6. Showing a comparison between the experimental test and FE simulation. Conclusions so far! The test speed should be increased in current test standards from 5.4 m/s.
6 The rotational accelerations seen in the current FE simulations (Phase 2 and 4) and the experimental tests (Phase 1) are high. The high rotational accelerations could either be induced by the tangential force between the snow and the helmet or it could be induced by the inertial propertied of the head. It is therefore too early to give a final recommendation to FIS on how an advanced ski helmet test standard should be designed. Next step Phase 35 will continue when Phase 1 and 2 is completed. Some of the video analysis in Phase 3 needs to be controlled by external party in order to secure the quality. We are still waiting for medical pictures from the accidents, which is important to validate the injury outcome computed by the FE model of the human head and brain. Further simulations will be conducted analysing different impact situations in order to analyse the importance of the tangential force compared to the inertial effects from the CG of the human head. The absence of the neck and the body should be investigated. Previous work shows that the absence of the neck and/or the body does not affect the rotational acceleration in a helmet impact situation. This conclusion might not be relevant as the impact surface is slippery. The final report from this project will then be review by at least two objective external parties. References Coming soon.
ASSESSING MOTORCYCLE CRASHRELATED HEAD INJURIES USING FINITE ELEMENT SIMULATIONS
ISSN 17264529 Int j simul model 9 (2010) 3, 143151 Professional paper ASSESSING MOTORCYCLE CRASHRELATED HEAD INJURIES USING FINITE ELEMENT SIMULATIONS Toma, M. * ; Njilie, F. E. A. * ; Ghajari, M. **
More informationSAFE A HEAD. Structural analysis and Finite Element simulation of an innovative ski helmet. Prof. Petrone Nicola Eng.
SAFE A HEAD Structural analysis and Finite Element simulation of an innovative ski helmet Prof. Petrone Nicola Eng. Cherubina Enrico Goal Development of an innovative ski helmet on the basis of analyses
More informationFIS Injury Surveillance System. Video analysis of 4 ACL injuries. 2012/13 World Cup season
FIS Injury Surveillance System Video analysis of 4 ACL injuries 2012/13 World Cup season Introduction Injury recording through the FIS Injury Surveillance System (FIS ISS) revealed that there were four
More informationDEVELOPMENT OF HELICOPTER SAFETY DEVICES
25 TH INTERNATIONAL CONGRESS OF THE AERONAUTICAL SCIENCES DEVELOPMENT OF HELICOPTER SAFETY DEVICES Wayne Lam, Cees Bil *RMIT University Keywords: helicopter, crash, simulation, MADYMO Abstract Recent investigations
More informationHelmet Performance and Design
Helmet Performance and Design Editors: Peter RN Childs, Anthony Bull, Mazdak Ghajari February 2013 i Imperial College London Published by: DEG Imperial College London Design Engineering Group, Department
More informationSafety performance comparisons of different types of child seats in high speed impact tests
Safety performance comparisons of different types of child seats in high speed impact tests Jia Hu Dazhi Wang Michael Mellor Guoqiang Chen Dayong Wang Zheng Li Yongguang Wang Xing Su Jianyong Ma Xiaodong
More informationFE SIMULATIONS OF MOTORCYCLE CAR FRONTAL CRASHES, VALIDATION AND OBSERVATIONS
FE SIMULATIONS OF MOTORCYCLE CAR FRONTAL CRASHES, VALIDATION AND OBSERVATIONS A. CHAWLA, S. MUKHERJEE, D. MOHAN, Dipan BOSE, Prakash RAWAT, Transportation Research & Injury Prevention Programme Indian
More informationMotorcycle accident reconstruction in VL Motion
Motorcycle accident reconstruction in VL Motion Presenter Nicola Cofelice ESR 14 AGENDA 1 Motorcycle accident reconstruction  Overview 2 Research progress 3 What s next? copyright LMS International 
More informationEFFECT OF VEHICLE DESIGN ON HEAD INJURY SEVERITY AND THROW DISTANCE VARIATIONS IN BICYCLE CRASHES
EFFECT OF VEHICLE DESIGN ON HEAD INJURY SEVERITY AND THROW DISTANCE VARIATIONS IN BICYCLE CRASHES S. Mukherjee A. Chawla D. Mohan M. Singh R. Dey Transportation Res. and Injury Prevention program Indian
More informationSTUDY ON STEERING COLUMN COLLAPSE ANALYSIS USING DETAILED FE MODEL
STUDY ON STEERING COLUMN COLLAPSE ANALYSIS USING DETAILED FE MODEL Tae Hee, Lee Byung Ryul, Ham Seong Oh, Hong Advanced Safety CAE Team / Hyundai Motor Co. Korea Paper No. 110262 ABSTRACT EASC(Energy
More informationPedestrian protection  Pedestrian in collision with personal car
Pedestrian protection  Pedestrian in collision with personal car Authors: Jiří Svoboda, Ing; Zdeněk Šolc, Ing. Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Automotive
More information1. Newton s Laws of Motion and their Applications Tutorial 1
1. Newton s Laws of Motion and their Applications Tutorial 1 1.1 On a planet far, far away, an astronaut picks up a rock. The rock has a mass of 5.00 kg, and on this particular planet its weight is 40.0
More informationCenter of Gravity. We touched on this briefly in chapter 7! x 2
Center of Gravity We touched on this briefly in chapter 7! x 1 x 2 cm m 1 m 2 This was for what is known as discrete objects. Discrete refers to the fact that the two objects separated and individual.
More informationChin Strap Forces in Bicycle Helmets
Torbjörn Andersson PerOlov Larsson Ulf Sandberg Chin Strap Forces in Bicycle Helmets SP Swedish National Testing and Research Institute Mechanics SP REPORT 1993:42 2 Abstract The objective of this experimental
More informationRotation, Rolling, Torque, Angular Momentum
Halliday, Resnick & Walker Chapter 10 & 11 Rotation, Rolling, Torque, Angular Momentum Physics 1A PHYS1121 Professor Michael Burton Rotation 101 Rotational Variables! The motion of rotation! The same
More informationPredicting throw distance variations in bicycle crashes
304 Int. J. Vehicle Safety, Vol. 1, No. 4, 2006 Predicting throw distance variations in bicycle crashes S. Mukherjee and A. Chawla* Department of Mechanical Engineering, Indian Institute of Technology,
More informationEQUATIONS OF MOTION: ROTATION ABOUT A FIXED AXIS
EQUATIONS OF MOTION: ROTATION ABOUT A FIXED AXIS Today s Objectives: Students will be able to: 1. Analyze the planar kinetics InClass Activities: of a rigid body undergoing rotational motion. Check Homework
More informationAssessing helmet impact damage
Assessing helmet impact damage Dr Charlotte Meeks QinetiQ SAFE Europe, April 15 th 17 th, Alicante Overview Background Overview of helmet impact testing Review of UK and US aircrew standards used in study
More informationSpinning Stuff Review
Spinning Stuff Review 1. A wheel (radius = 0.20 m) is mounted on a frictionless, horizontal axis. A light cord wrapped around the wheel supports a 0.50kg object, as shown in the figure below. When released
More informationExplaining Motion:Forces
Explaining Motion:Forces Chapter Overview (Fall 2002) A. Newton s Laws of Motion B. Free Body Diagrams C. Analyzing the Forces and Resulting Motion D. Fundamental Forces E. Macroscopic Forces F. Application
More informationPREDICTING THROW DISTANCE VARIATIONS IN BICYCLE CRASHES
PREDICTING THROW DISTANCE VARIATIONS IN BICYCLE CRASHES MUKHERJEE S, CHAWLA A, MOHAN D, CHANDRAWAT S, AGARWAL V TRANSPORTATION RESEARCH AND INJURY PREVENTION PROGRAMME INDIAN INSTITUTE OF TECHNOLOGY NEW
More informationAlpine Skiing. Official Events. Rules of Competition
ARTICLE X: The Special Olympics Canada (SOC) Official Sports Rules shall govern all SOC alpine skiing competitions. As a national sports program, SOC has created these rules based upon the Fédération internationale
More informationA Review of Vector Addition
Motion and Forces in Two Dimensions Sec. 7.1 Forces in Two Dimensions 1. A Review of Vector Addition. Forces on an Inclined Plane 3. How to find an Equilibrant Vector 4. Projectile Motion Objectives Determine
More informationBiomechanical analysis of the javelin at the 2005 IAAF World Championships in Athletics
Biomechanical analysis of the javelin at the 2005 IAAF World Championships in Athletics by IAAF 21:2; 6780, 2006 By Masatoshi Murakami, Satoru Tanabe, Masaki Ishikawa Juha Isolehto, Paavo V. Komi, Akira
More informationSTATIC AND KINETIC FRICTION
STATIC AND KINETIC FRICTION LAB MECH 3.COMP From Physics with Computers, Vernier Software & Technology, 2000. INTRODUCTION If you try to slide a heavy box resting on the floor, you may find it difficult
More informationPC1221 Fundamentals of Physics I Inertia Wheel
PC1221 Fundamentals of Physics I Inertia Wheel 1 Purpose Determination of the angular acceleration of the inertial wheel as a function of the applied torque Determination of the moment of inertia I of
More informationPhysics: Principles and Applications, 6e Giancoli Chapter 2 Describing Motion: Kinematics in One Dimension
Physics: Principles and Applications, 6e Giancoli Chapter 2 Describing Motion: Kinematics in One Dimension Conceptual Questions 1) Suppose that an object travels from one point in space to another. Make
More informationCOEFFICIENT OF KINETIC FRICTION
COEFFICIENT OF KINETIC FRICTION LAB MECH 5.COMP From Physics with Computers, Vernier Software & Technology, 2000. INTRODUCTION If you try to slide a heavy box resting on the floor, you may find it difficult
More informationName: Date: 7. A child is riding a bike and skids to a stop. What happens to their kinetic energy? Page 1
Name: Date: 1. Driving down the road, you hit an insect. How does the force your car exerts on the insect compare to the force the insect exerts on the car? A) The insect exerts no force on the car B)
More informationImportance of the Bicycle Helmet Design and Material for the Outcome in Bicycle Accidents
Proceedings, International Cycling Safety Conference 2014 1819 November 2014, Göteborg, Sweden Importance of the Bicycle Helmet Design and Material for the Outcome in Bicycle Accidents M. Fahlstedt 1,
More informationRelationships between linear and angular motion
Relationships between linear and angular motion Body segment rotations combine to produce linear motion of the whole body or of a specific point on a body segment or implement Joint rotations create forces
More informationMYMOSA Motorcycle and motorcyclist safety
EUROPEAN COMMISSION DG RESEARCH SIXTH FRAMEWORK PROGRAMME MARIE CURIE RESEARCH TRAINING NETWORKS MYMOSA Motorcycle and motorcyclist safety Deliverable no. e.g. 3.1 Dissemination level Work Package Author(s)
More informationLecture 6. Weight. Tension. Normal Force. Static Friction. Cutnell+Johnson: 4.84.12, second half of section 4.7
Lecture 6 Weight Tension Normal Force Static Friction Cutnell+Johnson: 4.84.12, second half of section 4.7 In this lecture, I m going to discuss four different kinds of forces: weight, tension, the normal
More informationChapter 5 Using Newton s Laws: Friction, Circular Motion, Drag Forces. Copyright 2009 Pearson Education, Inc.
Chapter 5 Using Newton s Laws: Friction, Circular Motion, Drag Forces Units of Chapter 5 Applications of Newton s Laws Involving Friction Uniform Circular Motion Kinematics Dynamics of Uniform Circular
More informationPhysics 11 Assignment KEY Dynamics Chapters 4 & 5
Physics Assignment KEY Dynamics Chapters 4 & 5 ote: for all dynamics problemsolving questions, draw appropriate free body diagrams and use the aforementioned problemsolving method.. Define the following
More informationChapter 10 Rotational Motion. Copyright 2009 Pearson Education, Inc.
Chapter 10 Rotational Motion Angular Quantities Units of Chapter 10 Vector Nature of Angular Quantities Constant Angular Acceleration Torque Rotational Dynamics; Torque and Rotational Inertia Solving Problems
More informationNewton s Laws of Motion
Newton s Laws of Motion Newton s Laws and the Mousetrap Racecar Simple version of Newton s three laws of motion 1 st Law: objects at rest stay at rest, objects in motion stay in motion 2 nd Law: force
More informationDetermining the Angular Velocity of Winks using High Speed Video. Yan Wang. 5/14/ Measurement and Instrumentation Prof.
Thursday 25 Determining the Angular Velocity of Winks using High Speed Video Yan Wang 5/14/2008 2.671 Measurement and Instrumentation Prof. Leonard Abstract Tiddlywinks is a strategy game founded in
More informationFriction and Gravity. Friction. Section 2. The Causes of Friction
Section 2 Friction and Gravity What happens when you jump on a sled on the side of a snowcovered hill? Without actually doing this, you can predict that the sled will slide down the hill. Now think about
More informationACCIDENT RECONSTRUCTION EXAMPLE A POSSIBLE MODALITY FOR ROLLOVER AFTER THE FACT STUDY
CONAT20042069 ACCIDENT RECONSTRUCTION EXAMPLE A POSSIBLE MODALITY FOR ROLLOVER AFTER THE FACT STUDY 1 Ciolan, Gheorghe, 1 Preda, Ion *, 1 Covaciu, Dinu 1 Transilvania University of Brasov, Romania KEYWORDS
More informationWorking Paper. Extended Validation of the Finite Element Model for the 2010 Toyota Yaris Passenger Sedan
Working Paper NCAC 2012W005 July 2012 Extended Validation of the Finite Element Model for the 2010 Toyota Yaris Passenger Sedan Dhafer Marzougui Randa Radwan Samaha Chongzhen Cui CingDao (Steve) Kan
More informationComputational Analysis of Stressstrain State, Dynamics, Strength and Stability of Loadbearing Concrete Structures of NPP Evaporative Cooling Towers
Prof. Alexandr Belostotskiy, Assoc. Prof. Sergey Dubinsky, PhD student Sergey Petryashev, PhD student Nicolay Petryashev Computational Analysis of Stressstrain State, Dynamics, Strength and Stability
More informationA Systematic Approach for Improving Occupant Protection in Rollover Crashes
SAE 2011 Government / Industry Meeting A Systematic Approach for Improving Occupant Protection in Rollover Crashes Jingwen Hu, PhD University of Michigan Transportation Research Institute King H. Yang,
More informationHIGH SPEED VIDEO APPLICATIONS IN THE FRAME OF THE HSS3 DEVELOPMENT AND QUALIFICATION PROGRAM
HIGH SPEED VIDEO APPLICATIONS IN THE FRAME OF THE HSS3 DEVELOPMENT AND QUALIFICATION PROGRAM John Richard BUTCHER 1, Matteo RENDINA 1, Reto HUBER 2 1 RUAG SPACE AG, Schaffhauserstr. 580, 8052 Zürich, Switzerland
More informationUnit 4 Practice Test: Rotational Motion
Unit 4 Practice Test: Rotational Motion Multiple Guess Identify the letter of the choice that best completes the statement or answers the question. 1. How would an angle in radians be converted to an angle
More informationEndofChapter Exercises
EndofChapter Exercises Exercises 1 12 are conceptual questions that are designed to see if you have understood the main concepts of the chapter. 1. Figure 11.20 shows four different cases involving a
More informationNewton s Laws PreTest
Newton s Laws PreTest 1.) Consider the following two statements and then select the option below that is correct. (i) It is possible for an object move in the absence of forces acting on the object. (ii)
More informationChapter 4. Kinematics  Velocity and Acceleration. 4.1 Purpose. 4.2 Introduction
Chapter 4 Kinematics  Velocity and Acceleration 4.1 Purpose In this lab, the relationship between position, velocity and acceleration will be explored. In this experiment, friction will be neglected.
More informationLesson 04: Newton s laws of motion
www.scimsacademy.com Lesson 04: Newton s laws of motion If you are not familiar with the basics of calculus and vectors, please read our freely available lessons on these topics, before reading this lesson.
More informationOn Predicting Lower Leg Injuries. for the EuroNCAP Front Crash
On Predicting Lower Leg Injuries for the EuroNCAP Front Crash Thomas Hofer, Altair Engineering GmbH Peter Karlsson, Saab Automobile AB Niclas Brännberg, Altair Engineering AB Lars Fredriksson, Altair Engineering
More informationIMU Components An IMU is typically composed of the following components:
APN064 IMU Errors and Their Effects Rev A Introduction An Inertial Navigation System (INS) uses the output from an Inertial Measurement Unit (IMU), and combines the information on acceleration and rotation
More informationFigure 3. Pressure taps distribution around the bus model (64 pressure taps)
Figure1. Double deck bus into the wind tunnel The aerodynamic balance, built by the authors according Tusche [11], is based on strain gage type cells arranged as a double Wheatstone bridge acquiring simultaneously
More informationComparisons of Motorcycle Helmet Standards Snell M2005, M2010/M2015, DOT and ECE 2205 Edward B. Becker, September 29, 2015
The following compares four standards: Snell M2005, Snell M2015/M2010, DOT, and ECE 2205. M2005 and the current DOT Standard (Federal Motor Vehicle Safety Standard 218) apply largely to motorcycle helmets
More informationGEOMETRY AND RUNNING OF THE ALPINE SKI FIS WORLD CUP GIANT SLALOM PART ONE  GEOMETRY
GEOMETRY AND RUNNING OF THE ALPINE SKI FIS WORLD CUP GIANT SLALOM PART ONE  GEOMETRY Wlodzimierz S. Erdmann, Andrzej Suchanowski and Piotr Aschenbrenner Jedrzej Sniadecki University School of Physical
More informationSTUDY OF SECOND ROW OCCUPANT PROTECTION IN FRONTAL VEHICLE CRASHES AND POTENTIAL RESTRAINT SYSTEM COUNTERMEASURES
STUDY OF SECOND ROW OCCUPANT PROTECTION IN FRONTAL VEHICLE CRASHES AND POTENTIAL RESTRAINT SYSTEM COUNTERMEASURES Ingo Mueller Dr. Steffen Sohr TAKATA AG, Berlin Germany Paper Number 130430 ABSTRACT Legal
More informationP113 University of Rochester NAME S. Manly Fall 2013
Final Exam (December 19, 2013) Please read the problems carefully and answer them in the space provided. Write on the back of the page, if necessary. Show all your work. Partial credit will be given unless
More informationVolvo Trucks view on Truck Rollover Accidents
Volvo Trucks view on Truck Rollover Accidents Mario Ligovic, Volvo Truck Corporation, Göteborg, Sweden INTRODUCTION Rollover is the most common heavy truck accident type. Experiencing a rollover is like
More informationA multibody head and neck model for low speed rear impact analysis
12th IFToMM World Congress, Besançon (France), June1821, 27 A multibody head and neck model for low speed rear impact analysis S. Himmetoglu *, M. Acar, A.J. Taylor, K. BouazzaMarouf Mechanical and
More informationMYMOSA  MOTORCYCLE ACCIDENT SIMULATION IN LMS VIRTUAL.LAB
FISITA2010SCP02 MYMOSA  MOTORCYCLE ACCIDENT SIMULATION IN LMS VIRTUAL.LAB AUTHORS: Ciubotaru, Leonard (1), Cofelice, Nicola (2), Moreno Giner, David * (2), Manka, Michal (3), Kang, Jian (2) (1) "Transilvania"
More informationLecture 15. Torque. Center of Gravity. Rotational Equilibrium. Cutnell+Johnson:
Lecture 15 Torque Center of Gravity Rotational Equilibrium Cutnell+Johnson: 9.19.3 Last time we saw that describing circular motion and linear motion is very similar. For linear motion, we have position
More informationEngineering Mechanics Dr. G Saravana Kumar Department of Mechanical Engineering Indian Institute of Technology, Guwahati
Engineering Mechanics Dr. G Saravana Kumar Department of Mechanical Engineering Indian Institute of Technology, Guwahati Module 5 Lecture 12 Application of Friction Part3 Today, we will see some more
More informationEQUATIONS OF MOTION: ROTATION ABOUT A FIXED AXIS
EQUATIONS OF MOTION: ROTATION ABOUT A FIXED AXIS Today s Objectives: Students will be able to: 1. Analyze the planar kinetics of a rigid body undergoing rotational motion. InClass Activities: Applications
More informationTHREE YEARS OLD CHILD HEADNECK FINITE ELEMENT MODELING. SIMULATION OF THE INTERACTION WITH AIRBAG IN FRONTAL AND SIDE IMPACT.
THREE YEARS OLD CHILD HEADNECK FINITE ELEMENT MODELING. SIMULATION OF THE INTERACTION WITH AIRBAG IN FRONTAL AND SIDE IMPACT. Meyer F., Roth S., Willinger R. Mechanical Institute of Fluids and Solids,
More informationFE Modeling of Innovative Helmet Liners
11 th International LSDYNA Users Conference Simulation (3) FE Modeling of Innovative Helmet Liners D. Hailoua Blanco*, A. Cernicchi*, U. Galvanetto * Dainese S.p.a via dell'artigianato 35, Molvena, Italy
More informationUniformly Accelerated Motion
Uniformly Accelerated Motion Under special circumstances, we can use a series of three equations to describe or predict movement V f = V i + at d = V i t + 1/2at 2 V f2 = V i2 + 2ad Most often, these equations
More informationRotational Motion & Moment of Inertia
Rotational Motion & Moment of nertia Physics 161 ntroduction n this experiment we will study motion of objects is a circular path as well as the effect of a constant torque on a symmetrical body. n Part
More informations r or equivalently sr linear velocity vr Rotation its description and what causes it? Consider a disk rotating at constant angular velocity.
Rotation its description and what causes it? Consider a disk rotating at constant angular velocity. Rotation involves turning. Turning implies change of angle. Turning is about an axis of rotation. All
More informationPEDESTRIAN HEAD IMPACT ANALYSIS
INTERNATIONAL JOURNAL OF MECHANICAL ENGINEERING AND TECHNOLOGY (IJMET) International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 6340(Print), ISSN 0976 6340 (Print) ISSN 0976 6359
More informationLAB 1 Graphing techniques and the acceleration of objects in free fall on Planet 'X' by R.E.Tremblay
Purpose: To learn how to make position and velocity verses time graphs when given the position of an object at various times. You will also learn how to determine initial velocity and acceleration from
More informationPHYSICS 111 HOMEWORK SOLUTION #10. April 8, 2013
PHYSICS HOMEWORK SOLUTION #0 April 8, 203 0. Find the net torque on the wheel in the figure below about the axle through O, taking a = 6.0 cm and b = 30.0 cm. A torque that s produced by a force can be
More informationNatural Convection. Buoyancy force
Natural Convection In natural convection, the fluid motion occurs by natural means such as buoyancy. Since the fluid velocity associated with natural convection is relatively low, the heat transfer coefficient
More informationInternational Educational EJournal, {Quarterly}, ISSN , VolumeII, IssueIV, OctNovDec 2013
Relationship of Selected Kinematic Variables with the Performance of Arijit Putatunda Assistant Director of Physical Education, St. Xavier s College, Jaipur, Rajasthan, India Abstract The purpose of this
More informationTire Sensors for the Measurement of Slip Angle and Friction Coefficient and Their Use in Stability Control Systems
Tire Sensors for the Measurement of Slip Angle and Friction Coefficient and Their Use in Stability Control Systems Gurkan Erdogan, Sanghyun Hong, Francesco Borrelli, Karl Hedrick Department of Mechanical
More informationNo Brain Too Small PHYSICS. 2 kg
MECHANICS: ANGULAR MECHANICS QUESTIONS ROTATIONAL MOTION (2014;1) Universal gravitational constant = 6.67 10 11 N m 2 kg 2 (a) The radius of the Sun is 6.96 10 8 m. The equator of the Sun rotates at a
More informationFric3. force F k and the equation (4.2) may be used. The sense of F k is opposite
4. FRICTION 4.1 Laws of friction. We know from experience that when two bodies tend to slide on each other a resisting force appears at their surface of contact which opposes their relative motion. The
More informationExperiment 2 Free Fall and Projectile Motion
Name Partner(s): Experiment 2 Free Fall and Projectile Motion Objectives Preparation PreLab Learn how to solve projectile motion problems. Understand that the acceleration due to gravity is constant (9.8
More informationDiscussion Problem #1:
Discussion Problem #1: In a weak moment you volunteered to be a human cannonball at an amateur charity circus. The cannon is actually a 3foot diameter tube with a big stiff spring inside which is attached
More informationVisual Physics 218 Projectile Motion [Lab 2]
In this experiment, you will be using your video equipment to evaluate twodimensional motion. It will be necessary to plot the data in an xycoordinate system and separate the data into x and y components.
More informationChapter 17 Planar Kinetics of a Rigid Body: Force and Acceleration
Chapter 17 Planar Kinetics of a Rigid Body: Force and Acceleration 17.1 Moment of Inertia I 2 2 = r dm, 單位 : kg m 或 slug m ft 2 M = Iα resistance to angular acceleration dm = ρdv I = ρ V r 2 dv 172 MOMENT
More informationRear Impact Dummy Biofidelity
GTR 7 Informal Working Group February 28 March 1 211 Brussels, Belgium Rear Impact Dummy Biofidelity Kevin Moorhouse, Ph.D. NHTSA YunSeok Kang Ohio State University Objectives & Tasks Evaluate biofidelity
More informationHydrostatic Pressure on a Partially and Fully Submerged Vertical Rectangular Surface R. Helm
Hydrostatic Pressure on a Partially and Fully Submerged Vertical Rectangular Surface R. Helm ABSTRACT. Hydrostatic Pressure Systems allow for the measurement and development of hydrostatic force and center
More informationProjectile Motion Introduction:
Projectile Motion Introduction: A projectile is a body in free fall that is subject only to the forces of gravity (9.81ms ²) and air resistance. An object must be dropped from a height, thrown vertically
More informationPHY121 #8 Midterm I 3.06.2013
PHY11 #8 Midterm I 3.06.013 AP Physics Newton s Laws AP Exam Multiple Choice Questions #1 #4 1. When the frictionless system shown above is accelerated by an applied force of magnitude F, the tension
More informationINFO & CONTACTS: tel
INFO & CONTACTS: tel. +39 035 4536661  www.neveplast.it  neveplast@neveplast.it Neveplast is an innovative product that has set itself the objective of allowing skiing and snowboarding throughout the
More informationLecture L2  Degrees of Freedom and Constraints, Rectilinear Motion
S. Widnall 6.07 Dynamics Fall 009 Version.0 Lecture L  Degrees of Freedom and Constraints, Rectilinear Motion Degrees of Freedom Degrees of freedom refers to the number of independent spatial coordinates
More information5.2 Rotational Kinematics, Moment of Inertia
5 ANGULAR MOTION 5.2 Rotational Kinematics, Moment of Inertia Name: 5.2 Rotational Kinematics, Moment of Inertia 5.2.1 Rotational Kinematics In (translational) kinematics, we started out with the position
More informationMOTION AND FORCE: DYNAMICS
MOTION AND FORCE: DYNAMICS We ve been dealing with the fact that objects move. Velocity, acceleration, projectile motion, etc. WHY do they move? Forces act upon them, that s why! The connection between
More informationClimbing Stairs. Goals. Launch 4.1 4.1
4.1 Climbing Stairs Goals Introduce students to the concept of slope as the ratio of vertical change to between two points on a line or ratio of rise over run Use slope to sketch a graph of a line with
More informationKINEMATICS OF PARTICLES RELATIVE MOTION WITH RESPECT TO TRANSLATING AXES
KINEMTICS OF PRTICLES RELTIVE MOTION WITH RESPECT TO TRNSLTING XES In the previous articles, we have described particle motion using coordinates with respect to fixed reference axes. The displacements,
More informationMotorcycle Sliding Coefficient of Friction Tests
Motorcycle Sliding Coefficient of Friction Tests Bruce F. McNally, ACTAR Northeast Collision Analysis, Inc. Wade Bartlett, PE, ACTAR Mechanical Forensic Engineering Services, LLP Presented at the 21 st
More informationRotation: Kinematics
Rotation: Kinematics Rotation refers to the turning of an object about a fixed axis and is very commonly encountered in day to day life. The motion of a fan, the turning of a door knob and the opening
More informationChapter 11. h = 5m. = mgh + 1 2 mv 2 + 1 2 Iω 2. E f. = E i. v = 4 3 g(h h) = 4 3 9.8m / s2 (8m 5m) = 6.26m / s. ω = v r = 6.
Chapter 11 11.7 A solid cylinder of radius 10cm and mass 1kg starts from rest and rolls without slipping a distance of 6m down a house roof that is inclined at 30 degrees (a) What is the angular speed
More informationP210 Graphing Problem Solving Lab
P210 Graphing Problem Solving Lab Objective: Learn how to present different types of data using graphs, both manually and using Microsoft Excel 7.0 Step one is to manually graph each of the following using
More informationPolitecnico di Torino. Porto Institutional Repository
Politecnico di Torino Porto Institutional Repository [Proceeding] Investigation of underplatform damper kinematics and its interaction with contact parameters (nominal friction coefficient) Original Citation:
More informationWorking Model 2D Exercise Problem 14.111. ME 114 Vehicle Design Dr. Jose Granda. Performed By Jeffrey H. Cho
Working Model 2D Exercise Problem 14.111 ME 114 Vehicle Design Dr. Jose Granda Performed By Jeffrey H. Cho Table of Contents Problem Statement... 1 Simulation SetUp...2 World Settings... 2 Gravity...
More informationMULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
Exam Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The following four forces act on a 4.00 kg object: 1) F 1 = 300 N east F 2 = 700 N north
More informationRelationship Between Linear and Angular Motion
Linear and Angular Kinematics (continued) 17 Relationship Between Linear and Angular Motion A very important feature of human motion... Segment rotations combine to produce linear motion of the whole body
More informationFriction and Newton s 3rd law
Lecture 4 Friction and Newton s 3rd law Prereading: KJF 4.8 Frictional Forces Friction is a force exerted by a surface. The frictional force is always parallel to the surface Due to roughness of both
More informationAngular Velocity. The purpose of this verification is to confirm that the angular velocity algorithm used by the program is working correctly.
E R I I C A T I O # 5 Angular elocity The purpose of this verification is to confirm that the angular velocity algorithm used by the program is working correctly. The example consists of a slope with two
More informationMaya 2014 Basic Animation & The Graph Editor
Maya 2014 Basic Animation & The Graph Editor When you set a Keyframe (or Key), you assign a value to an object s attribute (for example, translate, rotate, scale, color) at a specific time. Most animation
More information