A Study of Muscle Activation in a Mathematical Model of the Human Head and Neck

A model of the human head and neck that incorporates active and passive muscles is utilized in the analysis of non-impact loading in high “g” environments. The active muscles have the capability to be activated partially and in different combinations.The model is implemented in MADYMO using lumped parameters and Hill muscles. A comparison of simulation results with experimental data, generated by the Naval Biodynamics Laboratory (NBDL) for neck flexion and rebound, shows excellent agreement for a 15g impulsive load

Development of NHTSA’s Side Impact Test Procedure for Child Restraint Systems Using a Deceleration Sled : Part 2

This report presents the results of the continued research and development of child seat side impact tests using the deceleration sled at Kettering University’s Crash Safety Center. The objective of this test series was to gain further insight into the sensitivity of the side impact test fixture response. Test variations included speed of impact, weight of the fixture, and impact characteristics. Additionally, 20 child restraint system (CRS) specific tests were conducted using a fixed set of test parameters

A Study of Muscle Activation in a Mathematical Model of the Human Head and Neck

A model of the human head and neck that incorporates active and passive muscles is utilized in the analysis of non-impact loading in high “g” environments. The active muscles have the capability to be activated partially and in different combinations.The model is implemented in MADYMO using lumped parameters and Hill muscles. A comparison of simulation results with experimental data, generated by the Naval Biodynamics Laboratory (NBDL) for neck flexion and rebound, shows excellent agreement for a 15g impulsive load

Development of NHTSA’s Side Impact Test Procedure for Child Restraint Systems Using a Deceleration Sled : Part 2

This report presents the results of the continued research and development of child seat side impact tests using the deceleration sled at Kettering University’s Crash Safety Center. The objective of this test series was to gain further insight into the sensitivity of the side impact test fixture response. Test variations included speed of impact, weight of the fixture, and impact characteristics. Additionally, 20 child restraint system (CRS) specific tests were conducted using a fixed set of test parameters

Development of NHTSA’s Side Impact Test Procedure for Child Restraint Systems Using a Deceleration Sled : Part 1

This report presents the results of the research and development of the child seat side impact tests performed at Kettering University’s Crash Safety Center for NHTSA. The tests were conducted using a deceleration sled. The objective of this testing was to obtain data for the development of a side impact test procedure for child restraint systems

Crash Safety in the Introductory Physics Lab

Crash Safety in the Introductory Physics Lab Abstract In the field of vehicle occupant protection and crash safety, the Deceleration Sled offers researchers a controlled, repeatable, and relatively cost-effective means to test interior parts such as safety restraint systems. The sled can accelerate a 2000 lb payload to achieve a speed of 40 mph before a hydraulically controlled deceleration models the deformation of the vehicle structure during a crash. Understanding the dynamics of the sled and interpreting test results incorporates many of the core concepts of a first course in introductory physics. This application of physics principles is the inspiration for development and dissemination of curricular materials,appropriate for an introductory physics laboratory. Commonly available apparatus is put to the task: a low-friction cart on a track, with position and force sensors, accelerometers, and video analysis (using a low-cost webcam).This project will integrate the context of crash safety with current pedagogical techniques developed and proven in physics education research. The curricular materials have two goals: to help college and university students see the relevance of fundamental physics in engineering and practical applications, and to help these students learn concepts in physics more effectively and deeply. Activities address topics of motion, forces, energy, and momentum with pedagogy based in a guided inquiry/discovery model for lab instruction. Common misconceptions established in physics education research will be addressed intentionally, as students are encouraged to predict,test, and reflect on results. A library of video clips will be assembled and disseminated through the project web site, as well as editable curriculum materials.Assessment of the deployed activities in focus-group-type interviews and anonymous surveys has led to better understanding of students’ needs in an inquiry-based laboratory. Also, widely used instruments (the Force Concept Inventory and the Maryland Physics Expectation Survey)are included in the assessment phase of this project

Crash Safety in the Introductory Physics Lab

Crash Safety in the Introductory Physics Lab Abstract In the field of vehicle occupant protection and crash safety, the Deceleration Sled offers researchers a controlled, repeatable, and relatively cost-effective means to test interior parts such as safety restraint systems. The sled can accelerate a 2000 lb payload to achieve a speed of 40 mph before a hydraulically controlled deceleration models the deformation of the vehicle structure during a crash. Understanding the dynamics of the sled and interpreting test results incorporates many of the core concepts of a first course in introductory physics. This application of physics principles is the inspiration for development and dissemination of curricular materials,appropriate for an introductory physics laboratory. Commonly available apparatus is put to the task: a low-friction cart on a track, with position and force sensors, accelerometers, and video analysis (using a low-cost webcam).This project will integrate the context of crash safety with current pedagogical techniques developed and proven in physics education research. The curricular materials have two goals: to help college and university students see the relevance of fundamental physics in engineering and practical applications, and to help these students learn concepts in physics more effectively and deeply. Activities address topics of motion, forces, energy, and momentum with pedagogy based in a guided inquiry/discovery model for lab instruction. Common misconceptions established in physics education research will be addressed intentionally, as students are encouraged to predict,test, and reflect on results. A library of video clips will be assembled and disseminated through the project web site, as well as editable curriculum materials. Assessment of the deployed activities in focus-group-type interviews and anonymous surveys has led to better understanding of students’ needs in an inquiry-based laboratory. Also, widely used instruments (the Force Concept Inventory and the Maryland Physics Expectation Survey)are included in the assessment phase of this project

Evaluating Impact Attenuator Performance for a Formula SAE Vehicle

Formula SAE® is one of several student design competitions organized by SAE International. In the Formula SAE events undergraduate and graduate students are required to conceive, design, fabricate and compete with a small, formula-style, race car. Formula SAE safety rules dictate a 7 m/s (or approximately 15.65 mph) frontal crash test for nose mounted impact attenuators. These rules are outlined in section B3.21 of the Formula SAE rule book. Development and testing methods of these energy absorbing devices have varied widely among teams. This paper uses real world crash sled results to research methods for predicting the performance of aluminum honeycomb impact attenuators that will comply with the Formula SAE standards. However, the resulting models used to predict attenuator performance may also have a variety of useful applications outside of Formula SAE. In this paper, various energy absorbers were mounted to a free rolling trolley sitting on top of a crash sled. The sled was launched so that the trolley with the attached attenuator was allowed to strike a rigid barrier. This resulted in a sudden deceleration measured by accelerometers attached to the trolley. The resulting deceleration from each impact attenuator was then correlated to predicted pulses from theoretical calculations. The lessons learned from extensive testing will be discussed including comparisons between size, shapes, and material properties of energy absorption devices. Additionally, a final theory will be presented describing the ideal way to predict impact attenuator performance. Ultimately it will be shown that, given a known geometry, material properties, and safety factor, the behavior of an impact attenuator can be predicted accurately enough that testing will only be needed as verification. This study will ultimately benefit all Formula SAE® teams, as it will help speed up development time and cut costs, while providing a proven method for creating attenuators that will perform to SAE standard

Evaluating Impact Attenuator Performance for a Formula SAE Vehicle

Formula SAE® is one of several student design competitions organized by SAE International. In the Formula SAE events undergraduate and graduate students are required to conceive, design, fabricate and compete with a small, formula-style, race car. Formula SAE safety rules dictate a 7 m/s (or approximately 15.65 mph) frontal crash test for nose mounted impact attenuators. These rules are outlined in section B3.21 of the Formula SAE rule book. Development and testing methods of these energy absorbing devices have varied widely among teams. This paper uses real world crash sled results to research methods for predicting the performance of aluminum honeycomb impact attenuators that will comply with the Formula SAE standards. However, the resulting models used to predict attenuator performance may also have a variety of useful applications outside of Formula SAE. In this paper, various energy absorbers were mounted to a free rolling trolley sitting on top of a crash sled. The sled was launched so that the trolley with the attached attenuator was allowed to strike a rigid barrier. This resulted in a sudden deceleration measured by accelerometers attached to the trolley. The resulting deceleration from each impact attenuator was then correlated to predicted pulses from theoretical calculations. The lessons learned from extensive testing will be discussed including comparisons between size, shapes, and material properties of energy absorption devices. Additionally, a final theory will be presented describing the ideal way to predict impact attenuator performance. Ultimately it will be shown that, given a known geometry, material properties, and safety factor, the behavior of an impact attenuator can be predicted accurately enough that testing will only be needed as verification. This study will ultimately benefit all Formula SAE® teams, as it will help speed up development time and cut costs, while providing a proven method for creating attenuators that will perform to SAE standards

Sensitivity Analysis of Hill Muscle Parameters

A computational, rigid body model of a 50th percentile male head and neck utilizing 15 Hill Muscle pairs is used to study the sensitivity of Hill Muscle Model parameters. A 15g linear acceleration is applied within the transverse plane at the lowest vertebral level of the neck (T1). The resultant linear acceleration of the head is analyzed. In response is minimally affected. The peak accelerations did change, and in the case of varying muscle activation, the peak acceleration changed significantly, 36%. Each of the other parameter variations affected the peak acceleration of the head by less than 5%. Overall, the muscle activation parameter has the most significant influence on the response of the system