Attachment J.6 FOIL Operating Manual.pdf

ii

Technical Report Documentation Page

1. Report No.

2. Government Accession No.

3. Recipient's Catalog No.

4. Title and Subtitle

FEDERAL OUTDOOR IMPACT LABORATORY

OPERATION MANUAL

5. Report Date September 2009

6. Performing Organization Code

7. Author(s) Dhafer Marzougui, Pradeep Mohan, and Steve Kan

8. Performing Organization Report No.

09-001

9. Performing Organization Name and Address The National Crash Analysis Center The George Washington University Ashburn, VA 20147

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

DTFH61-02-X-00076

12. Sponsoring Agency Name and Address Office of Safety and Traffic Operation R&D Federal Highway Administration U.S. Department of Transportation 6300 Georgetown Pike McLean, VA 22101-2296

13. Type of Report and Period Covered Operational Report

14. Sponsoring Agency Code

15. Supplementary Notes Agreement Officer’s Technical Representative (AOTR) – Kenneth Opiela

16. Abstract

This Report covers the operation of the FHWA Federal Outdoor Impact Laboratory (FOIL) located at The Turner-Fairbank Highway Research Center (TFHRC) in Mclean Virginia. The report details guidelines for the operation and maintenance of the facility and equipment available at the laboratory.

It also presents recommended procedures for perfuming and documenting full-scale and component testing performed at the laboratory.

17. Key Word FOIL, Roadside Hardware, Transportation Safety, Crash Testing, Pendulum, Bogie, Full-Scale

18. Distribution Statement Copyrighted. Not to be copied or reprinted without consent from sponsor

19. Security Classif. (of this report) Unclassified

20. Security Classif. (of this page) Unclassified

21. No. of Pages

22. Price

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized iii iv

TABLE OF CONTENTS

TABLE OF CONTENTS .............................................................................................. iv

LIST OF FIGURES ........................................................................................................ v

1........ INTRODUCTION

2........ BACKGROUND

3........ OBJECTIVE

4........ SAFETY

5........ FACILITY LAYOUT

6........ EQUIPMENT DESCRIPTION

7........ PENDULUM TEST PROCEDURES

8........ VEHICLE PREPARATION PROCEDURE

9........ PROCEEDURE FOR OPERATING OTHER EQUIPENTS AT FOIL

10...... REFERENCES

APPENDIX A: TESTING CHECK LIST .................................................................. A1

APPENDIX B: VEHICLE DOCUMENTATION CHARTS ..................................... B1

APPENDIX C: TEST SUMMARY REPORT SAMPLE ........................................... C1

APPENDIX D: FOIL EQUIPMENT LIST ................................................................ D1

APPENDIX E: FOIL HAZARDOUS MATERIAL LIST .......................................... E1 v

LIST OF FIGURES

Figure 1: Arial View of FOIL

Figure 2: Hydraulic Propulsion System

Figure 3: Screen Showing Status of Propulsion System Components

Figure 4: NAC Memrecam K3 High Speed digital Camera

Figure 5: Typical Camera Connections Setup

Figure 6: Data Acquisition Components

Figure 7 Movias Pro Motion Analysis Software

Figure 8: Accelerometers

Figure 9: Load Cell

Figure 10: Sample Gyro Transducer

Figure 11: String Pot Model 162-3405

Figure 12: Tape Switch

Figure 13: Reusable Bogie Vehicle

Figure 14: Crushable Frontal Structure

Figure 15: Configuration of the Crushable Frontal Structure

Figure 16: Pendulum Support Structure

Figure 17: 2,000 kg (4,400 lb) Pendulum Mass with Rigid Impact Surface Attached

1- INTRODUCTION

The Federal Outdoor Impact Laboratory (FOIL) is a state-of-the art fully equipped crash testing laboratory and research facility. It is located at the FHWA's Turned-Fairbank Highway Research Center in McLean, Virginia, a suburb of Washington, D.C. It is designed to stage controlled high-speed motor vehicle collisions into roadside appurtenances. The crash tests conducted at FOIL are used to extend the research engineer’s understanding of a crash event and consequently develop some guidelines for regulations that improve roadside hardware safety performance.

Routine certification or compliance testing of roadside safety structures (testing performed to insure compliance with existing safety standards) is not conducted at the FOIL.

In recent years, all testing at FOIL has focused on supporting finite element computer analyses.

Testing is typically employed subsequent to computer-generated crash predictions to confirm the accuracy of these prior computer predictions. This insures that the roadside structures tested – structures that are typically located in close proximity to our Nation’s roadways – function as intended when struck by a motor vehicle to insure public safety. And because FE simulations can be done before the actual crash testing, the simulation data is often used to design the test fixtures and set ideal test specifications, including impact speed and angle.

FOIL capabilities include fully instrumented vehicle to roadside hardware, vehicle-to-vehicle head-on, frontal offset, and front-to-side impacts with the second vehicle stationary. Vehicle front-into-rear tests as well as roof crush drop tests can also be conducted.

A swinging pendulum structure is also available for impact testing of structural components.

Dynamic-impact testing of structural components is often performed to assist in the development of accurate computer models of the structures – and subsequently used to accurately predict the collision event. With a mass of up to 4400 lbs, this gravity-propelled pendulum can attain impact speeds in excess of 20 mi/hr. It can simulate both large (2,000 kg) vehicle weights and small (820 kg) vehicle weights.

Additionally, a surrogate vehicle (Bogie) with crushable aluminum honeycomb nose, simulating a small vehicle’s crush characteristics, is also available at FOIL. This reusable vehicle is used to simulate front impacts into roadside narrow objects. Bogie is also used as a sled for component testing.

A summary of the FOIL capabilities are listed below:

• State of the art hydraulic propulsion system

• Facility control system (via a central PC)

• Closed loop track rail system with a low profile extruded aluminum rails

• Front and side impact into roadside hardware

• Vehicle weight vs. speed:

o 2000 kg at 100 km/h (NCHRP 350, TL-3) o 8000 kg at 80 km/h (NCHRP 350, TL-4)

• Speed accuracy within ±0.5 km/h

• Track length: 67 m

• 110 m vehicle runoff area

• A pendulum test device that simulates two vehicle weights into poles, posts, and other breakaway support structures o 2000 kg vehicle at 35 km/h o 830 kg vehicle at 35 km/h

• A surrogate bogie vehicle that uses aluminum honeycomb material in a sliding nose to simulate the crush characteristics of an 830 kg small vehicle, more specifically a 1979 Volkswagen Rabbit

• Instrumented rigid pole for front and side impacts (up to 8 load cells)

• 80 channels of ultra high speed 16 bit A/D converter, ultra low-noise design, and fully programmable signal conditioning data acquisition system

• Digital and 16 mm high speed photography o 1280x1024 pixels at 1000 fps o Selectable frame rate up to 10000 fps

This report gives general guidelines on how to operate the FOIL. It starts with the background and objective of the FOIL facility shown in sections 2 and 3 respectively. Safety guidelines are presented in section 4. Section 5 gives an overview of the facility layout. Description of the different equipment at FOIL is presented in section 6. This is followed by the testing procedure when a vehicle is used (section 7). The procedure when a pendulum is used in presented in section 8. The last two sections (9 and 10) give the management activities and other miscellaneous activities.

2- BACKGROUND

The FOIL was constructed during the early 1980s and commenced operations in the summer of 1985. Over the ensuing years, this facility’s purpose and function has changed and adapted with the times. When the FOIL was first opened, motor vehicle crash testing was the only method available to evaluate the crashworthiness of roadside structures – i.e. to confirm the potential for occupant injury mitigation during motor vehicle collisions into roadside structures. Examples of these structures include concrete median barriers, metal guardrails, breakaway sign and lighting supports, and energy absorbing crash cushions to name a few.

During this early period, crash testing – aided by high-speed photography and electronic data recording devices – was the single preeminent technology used by engineers to better understand the crash event. This event encompasses a series of complex interactions – first, the collision between the motor vehicle and the roadside safety structure and, subsequently, the collision between the vehicle occupants and the interior surfaces or the safety restraints inside the passenger compartment.

With the advent of high-speed, high-memory capacity computers in the early 1990s, computer technology reached the point where vehicle crash outcomes could be accurately predicted using the computer. Specialized finite-element software – appropriate for depicting the physics of motor vehicle collisions – is now used extensively to predict collision outcomes. Because of this new technology, crash testing is now primarily used to confirm the accuracy of these computer predictions. As such, during the early 1990s, the function of the FOIL changed substantially. It is now used primarily to confirm the crash predictions obtained using computer based crash technology.

More recently, as a result of the September 11, 2001 terrorist attack on the World Trade Center in New York City, building security suddenly has became a focus and a priority for the U.S.

government. The need to develop perimeter security devices and structures – used to prevent the unwanted intrusion of speeding motor vehicles into areas adjacent to government buildings and other critical facilities – is now necessary and urgent. Examples of perimeter security devices and structures include crash resistant bollards, stanchions, concrete walls, large planters filled with dirt and plants, and energy absorbing fences – all of which must be capable of stopping a speeding heavy truck within a very, very short distance. Because of this urgent need, the FOIL has been enlisted to aid in the development of these structures.

In April 2002, the FOIL propulsion was fully upgraded. The drop weight system has been replaced with a state-of-the-science hydraulic system. The new system is the first of its kind in the United States. Prior to testing, the test vehicle’s weight, the length of the runway up to the test structure, and the required collision speed is input into the computer controlling the propulsion system. Upon initiating a test, the computer automatically adjusts the flow rate of hydraulic fluid into two hydraulic motors propelling the test vehicle. This controlled flow into motors precisely controls the test vehicle’s acceleration as it is powered up to the desired test speed. At impact into the test structure, the speed of the test vehicle is accurate to within 0.5 mi/hr of the desired collision speed. Just prior to impact, the propulsion system is disengaged from the test vehicle. At impact, the test vehicle is completely unconstrained and freewheeling as it collides with the test structure. This unconstrained vehicle motion approximates the conditions associated with a “real-world” crash on our Nation’s roadways.

Test instrumentation at FOIL has also been updated. These instrumentations includes speed traps, accelerometers, angular motion rate gyros, and load cells for determining the velocity, acceleration, roll, pitch, and yaw motions of the test vehicle, and the impact loads resulting from high-speed collision. Data collection from this instrumentation is accomplished using on-board solid-state recording devices and is transferred to the data processing center using a telemetry system. Visual documentation and analysis of the test is achieved through the use of high-speed digital cameras. Using these state-of-the-science high technology digital cameras, the impact and deformation of the test vehicle and test structure is visualized – and almost immediately after the test this visual information can be reviewed and analyzed.

3- OBJECTIVE

Crash testing has played a major role in highway and automotive safety research over the past 30 years. Full-scale testing laboratories have increased in sophistication with respect to the variety of impact scenarios, data acquisition, high-speed digital photography, and sensing. The Turner- Fairbanks Federal Impact Outdoor Laboratory (FOIL) has undergone major enhancements in its capabilities over the past few years through the addition of a sophisticated hydraulic propulsion system that enables testing 2000 Kg vehicles at speeds in excess of 100 kph. This new system is now controllable using a single computer workstation, with multiple channel I/O coordinating all the data acquisition, cameras, and other sensory functions. The pendulum impactor has also been enhanced and used for a variety of research tests in support of material characterization.

Simultaneously, finite element models of roadside safety appurtenances have been emerging and progressing in sophistication during the past decade. Many issues have been raised concerning the capabilities and limitations of the FE methods to accurately simulate crashes of vehicles with these appurtenances. In certain cases (designs), complex models have been developed which can be validated fully using crash test data. In other cases, there are many FE program constraints that need to be overcome by research in order to achieve higher fidelity models of roadside hardware. Other areas of research involve the detailed modeling of components of vehicles with which the barrier comes in contact. Among areas of improvements are enhancement of existing material models for failure, new models to better represent characteristics of various materials, e.g. soil, concrete, glass, etc. and particularly in their contact with other embedded objects and their respective failure.

The research at FOIL will focus on crash testing for the purpose of validating and improving these models, as well as testing new hardware concepts after sufficient amount of FE based design is conducted. In addition, research will be conducted to improve material models, failure modeling, verification of various modeling approaches which cumulatively advance the state-of-the-art and accuracy in simulating crashes of roadside hardware. These efforts require impact or crash testing at both component and full-scale vehicle level.

Testing on a variety of roadside hardware including, but not limited to, guardrails, end and transition terminals, crash cushions, sign supports, luminaries, rigid poles, and other devices will be conducted at FOIL. These tests will serve to either verify the performance of new design concepts or to validate FE models of new concepts.

Further more, FOIL researchers will continuously evaluate the capabilities and recommend improvements for conducting the mentioned tests as well as more sophisticated crash testing.

This effort is essential as impact testing for the purpose of developing very accurate detailed FE models is very sophisticated and requires an advanced research testing facility.

4- SAFETY

Safety should be given the highest priority when performing the tasks at FOIL. Machinery, equipment, and tools, especially the propulsion system, operate under high pressure, high temperate, and/or high voltage and special care has to be taken when using these devices. FOIL operational personnel must constantly endeavor to maintain safe working conditions and to protect themselves and other personnel from injury. They must be familiar with all safety guidelines and warnings listed in the equipment and machinery user manuals before operating them.

4.1- Scope In order for a safety program to be effective, it is vital that rules be established, monitored by responsible individuals, and implemented at all levels of employment. Employees are expected to utilize proper judgment in their personal habits. All employees are required to be in good physical condition to meet their daily working obligations when they report to work.

4.2- Purpose To establish procedures for providing a safe and efficient work environment, all FOIL employees are expected to comply with safety procedures designated for this purpose. Employees at all levels must work diligently to execute the FOIL's policies of maintaining safety and occupational health. Safety does not occur by chance, it is the result of careful attention to all operations by those who are directly and indirectly involved. Additionally, a safe operation is organized, clean, and efficient. If every employee views accidents in the same way, we will be in a better position not only to control accidents, but also to assure that all aspects of our safety program will be strictly adhered to and that the intent of this program will be followed to the letter. Any recommendations to improve this Safety Program are encouraged.

4.3- Safety Rules The following safety rules apply to all employees. They are for the guidance and protection of every worker. Safety is the responsibility of every employee. Everyone’s cooperation is necessary in order to create and maintain safe working conditions. Each employee must think about safety and take appropriate actions to keep their work areas clean and free from hazards. Any employee performing an unsafe act is a hazard and will be subject to appropriate disciplinary action up to and including discharge if warranted. Management will not condone an employee performing any unsafe act. Safety rules that should be followed by employees, managers, and supervisors are listed below.

Employees:

• Always wear safety protection appropriate for your job. For example, suitable eye protection must be worn when grinding, chipping, or using compressed air tools, or in any other operation where the employee is exposed to flying particles.

• Report all injuries to your supervisor at the time they occur, no matter how minor you think the injury may be.

• Use the appropriate lifting equipment. Only lift what you can safely handle. Ask for help when heavy objects are to be lifted or moved and always lift correctly.

• Refrain from fighting, horseplay, and throwing objects at all times.

• Ask if you are unsure of the safe and/or correct way to do a job.

• Never block aisles, workspaces, fire extinguishers, exit doors, and control cabinets.

• Use tools and equipment in a proper and safe manner. Never use defective hand tools.

Exchange the tools or see that defective tools are repaired.

• Adhere to the Drug & Alcohol Policy. Drinking alcoholic beverages, intoxication, or possession of illegal drugs on FHWA/FOIL property, or being under the influence of alcohol or any other illegal substance is not, and will not be permitted.

• Do not operate any machine or other equipment unless you are specifically trained and authorized to do so.

• Machines and work areas must be kept clean at all times. Good housekeeping is essential to safe efficient work.

• Remember the position of all safety switches and how to activate them. Safety devices such as guard covers, lockout devices, control switches, etc. must be used properly.

• Never point a compressed air hose at yourself or fellow employee. Never dust yourself off using compressed air.

• Never place a tool where it can injure you or anyone else by slipping, rolling, or falling. When using tools on a ladder, scaffold, or platforms, keep them in a container or otherwise secured from falling.

• Notify area supervisor immediately of any hazardous working situation.

• Any employee engaging in conduct inconsistent with his/her medical restrictions or which operates to further or lengthen the period of work related disabilities should be subject to discipline up to and including discharge.

• Jewelry, rings, bracelets, watch chains, key chains, ties, loose or ragged clothing should not be worn when using machinery, as these items might catch causing serious accidents such as loss of fingers or hands.

• Keep the floor clean and dry of oil and water.

• Scrap and refuse materials should be placed in proper containers. Keep your general working area free from clutter and obstacles.

Supervisors & Managers:

• Responsible for ensuring safety of all employees under their management.

• Responsible for training employees in safe working practices and safety regulations.

• Remove all unsafe working conditions immediately upon discovery and ensure situation is resolved appropriately.

• Investigate any reported accident immediately and complete the approved company accident report within one working day.

• Consider an employee's accident record and attitude toward safety during performance evaluation.

• Enforce all safety rules with a positive attitude and stress the importance of a safe working environment to all.

• Be prepared to enforce disciplinary action for any safety rule violations. Comply with all applicable safety rule and regulations.

Personal Protective Equipment:

• Eye and Face Protection: Safety glasses with side shields are required in all work areas. Goggles and/or face shields are required when grinding or handling certain chemicals; Welding hoods are required for welding operations. Employees who wear prescription glasses may order such glasses through the company.

• Hearing Protection: Earplugs or earmuffs may be required in some areas due to elevated noise levels. (Cotton in the ears is not acceptable as hearing protection.)

• Respiratory Protection: Respirators are required to be worn in any area where excessive air contaminants exist such as paints, mists, dusts, vapors, and others. You may not see it or smell it, but dusts, fumes, vapors, and gases may be hazardous to your health.

4.4- Accident Investigation

Procedure:

There are five steps to follow in case of an accident investigation:

• Reporting - It is the employees’ responsibility to immediately report all accidents and unsafe conditions to his/her supervisor no matter what the severity.

• Investigating - Determine if it was a non-injury accident or an accident that caused personal injury. You should investigate both accidents the same way with level of seriousness establishing the amount of management involvement.

• Analysis - -First determine if it was a preventable injury and then list the items damaged.

Then review the relationship of the accident with the role of the job, and determine if there was an unsafe condition or an unsafe act or omission present.

• Correcting - In correcting the problem, cooperation is needed from top management all the way down to the part-time workers. Reviewing past events will aid in trying to pick out any trends, or any repeat offenders that might need refresher training. Supervisors will then discuss the accident with the information presented to them and try to prevent reoccurrence.

• Follow-Up - Follow up describes the items that need to be repaired or replaced, date of initial action, date of completion, and a remark section. A good follow up is necessary to prevent further accidents.

Supervisor Role:

Accident investigation is the responsibility of all levels of management. By having the supervisors report all accidents it shows the employees that accident prevention will be taken seriously. Supervisors need to know about accident causes and what methods should be taken when investigating an accident. In most cases the supervisor knows the jobs responsibilities and is able to pick out unsafe conditions. Supervisors need to react immediately to prevent reoccurrence of the accident. This might include retraining, eliminating a machine or adding a safety device all which are dependent on the type of accident.

Accident/Incident Report Form Name: Date of Incident: Age:

Time of Incident: Years W/Co.:

Department/Position:

Location of Incident:

Person Notified: Date: Time:

Witness: Yes No if yes, Who:

Injury or Damage:

Describe the Pain:

Describe What Happen:

Activity at Time Of Injury Or Occurrence:

What Corrective Action Was/Will Be Taken?

Did you receive Medical Treatment For Your Injury: Yes No If Yes Where:

ANALYSIS OF ACCIDENT CAUSE

Unaware of (job) Hazards Tried to Avoid Extra Effort Inattentive to Hazards Acted to Avoid Discomfort Low Level of Job Skill Influence of Fatigue/Illness Tired to Gain or Save Time Other

ACTIONS TAKEN TO PREVENT REOCCURRENCE

Re-instruction of Person(s) Equipment Repair/Replace Reprimand of Person(s) Install Safety Guards Action To Improve Clean-up Action To Improve Construction Other Use of Safer Materials Other

Employee Signature:

Supervisor Signature:

5- FACILITY LAYOUT

The FOIL facility consists of six main areas: 1- the propulsion system trailer, 2- the test control center trailer, 3- the vehicle preparation garage, 4- the track, 5- the runway, and 6- the pendulum area. These areas are shown in aerial view of the FOIL below (Figure 1). Additionally, several storage trailers are located at different areas of the facility.

Figure 1: Arial View of FOIL

6- EQUIPMENT DESCRIPTIONS

6.1- Vehicle Propulsion System

The original FOIL propulsion system was fully rebuild on April 2001 and was further upgraded on June 2003. The purpose of these upgrades was to enable testing of roadside safety hardware at test levels 3 and 4 of the NCHRP “Recommended Procedures for the Safety Performance Evaluation” Report 350 [1]. After the first upgrade the system was capable of bringing a 2000 kg (4400 lb) vehicle to a speed of 100 km/hr (62 mph) which is the recommended test conditions for test level 3 of Report 350. With the second upgrade, the system can pull an 8000 kg (18,000

lb) vehicle to a speed of 80 km/hr (50 mph), the conditions for test level 4 of report 350.

To achieve these test conditions, the original FOIL propulsion system, which was based on a drop weight concept, was replaced by a high-power hydraulic system. This system can produce over 10,000 Nm torque which makes it one of the most powerful systems in the world. This was needed to compensate for the limited track length available at FOIL, 67-meter (220 ft.).

The hydraulic propulsion system was built in Germany by the Messring Company. It was transported to FOIL, assembled, and calibrated on site by Messring engineers. Figure 2 shows the system as installed at FOIL. It is composed of three main units: the hydraulic unit, the buffer unit, and the drive unit. The hydraulic unit consists of a 400 liter oil tank and a hydraulic pump.

The main components of the buffer unit are two large pistons ( liter) and 32 nitrogen tanks. The drive system consists of two hydraulic motors, valves, drive shafts, bake disks, and cables.

When the propulsion system is on idle (not in use), the oil is stored in the hydraulic unit’s tank and the system is under low pressure. Upon activating the system, oil from the tank is transferred into the two buffer unit pistons by way of the hydraulic pump. The pump continues to fill the pistons until a required pressure (depending on test vehicle mass and target speed) is reached. This typically takes about 2 minutes. The nitrogen tanks are used to apply the pressure inside the pistons. Once filling is completed, the system is under high energy/pressure and ready for final activation. In the final step, the drive system valves are release and the high pressurized oil is fed into the motors. The motors spin the drive shafts and pull the drive unit cable which is attached to the test vehicle. Throughout the cable pull process, the vehicle calculated speed is compared to the actual speed and the motor rotation (RPM) is adjusted accordingly via its servo valves. This closed loop correction process ensures that the target is obtained with high accuracy. Typically, the actual speed is with 0.5 km/hr of the target speed.

The operation process of the propulsion system is fully automated. The system is connected to high-end personal computer and the Messring software, “CarshSoft”, is used to control the different components of the system. Details on the software operation are described in the section 6.2. Additional information about the propulsion system, its operation, maintenance, safety guidelines, electric diagrams, mechanical diagrams are included in the Messring User’s manual [2].

Figure 2: Hydraulic Propulsion System.

6.2- Vehicle Propulsion System Software

Operating the propulsion system is fully automated through the use of the “CarshSoft” Messring software. The software is installed on a Personal computer that is connected to the propulsion system through a special interface card and cables. The software is configured such that the test is setup, performed, and analyzed in systematic chronological steps. Additionally, during these steps, the software shows the status of all components of the propulsion system such as the hydraulic pressure in the pistons, oil pressure in the reservoir, the nitrogen tanks pressure, cable tension, cable/trolley speed, propulsion system brake pressure, and emergency brake pressure, trolley position, tanks, etc. The status is displayed is easy t read visual gauges. Figure 3 shows a Crashsoft screen with the status gauges. Additionally, during each step of the procedure, the software checks the system and ensures that all components are functional and the step can be safely executed. This minimizes operational errors and allows for safe operation of the system.

The software gives warning and error messages if a malfunction is detected and the step will not execute until all errors are corrected.

Figure 3: Screen Showing Status of Propulsion System Components

The software can be run in one of two models: direct control or automated control. The mode s selected when CrashSoft is first started. The direct control mode permits to manually operate all major functions of the propulsion system. This is used for the test preparation, system maintenance, and test data analysis processes. The automatic control is used to perform the test once the test setup is complete, the facility is prepped, and test is ready to run.

The propulsion system testing procedure is performed in three main phases: 1- setting up the test, 2-conducting the test, and 3- analyzing propulsion system data.

During the test setup, first phase, the “CrashSoft workshop” software is started. This software will guide the user to setup the test in a step by step process. During each step a window is displayed prompting the user for some information. The user enters this information and pressing the “next” button to move to the next step. The steps are listed below. Upon completing the steps, a configuration file is generated and stored for later use in phase 2.

Step 1: During the first step, the user is prompted for a test number and title. The user can type the test number and title or let the software randomly generate this information based on date and time. A project type needs to be filled as well. The project can be “vehicle test”, “bogie test”, “vehicle with brake test”, or a “calibration test”. Other projects types are available but are not typically used at FOIL. Depending on the test to be performed the user selects one of the project types.

Step 2: Upon selecting the test number, title, and project type, the user is asked to choose whether on not a braking system is installed and whether or a not a drive system will invoked in the test. Typically both these options are used for the tests conducted at FOIL.

Step 3: The user is then prompted for whether or not a vehicle will be used in the test. Pull tests, without a vehicle, are performed before each test to warm up the system and ensure that all components of the propulsion system are functional. Typically three pull tests are performed prior to the actual test. Depending on whether a pull test or an actual test is to be performed, the user selects the appropriate answer.

Step 4: Next, the user is asked if a braking system is installed in the vehicle. If a vehicle braking system is present, it is checked during the testing procedure (phase 2) to ensure that it is active and operational. The barking system is activated automatically once the test is complete. It can also be activated using the emergency button.

Step 5: In the last step, the user is prompted for the test configuration parameters. This includes the vehicle mass, target speed, start position in the track, release position in the track, constant velocity distance, free distance, and acceleration rate range (+ or – in g/s).

Vehicle mass is entered in kg and target speed in km/hr. The vehicle initial position is referenced from a point on the track furthest away from propulsion system. The reference zero point and equal distance intervals are labeled on the actual FOIL track. A typical number for the start position is 62.5m. This gives the longest pull distance and consequently the lowest acceleration of the vehicle during the pull. The release point is when vehicle is disengaged from the propulsion system cables and trolley. The release position is entered in the same reference scale labeled on the track. Typically, a 2.5m release position is used for optimum pull length and vehicle acceleration. The constant velocity distance represents the distance where the vehicle is kept at constant speed (no acceleration) prior to release. Typical values are between 2 and 5m are used. The free distance is the distance between the release point and the impacted object. This is needed to adjust for the loss of vehicle speed while the vehicle is free wheeling between release time and impact time. The release velocity is automatically set slightly higher than the target impact velocity based on this free distance (this just an approximation and could vary depending on surface type and condition). The last parameter is the acceleration rate range.

This is typically set between -1 and +1 g/s. This may need to be changed when the propulsion system is operated close to its limits (in vehicle speed and mass).

Once all above steps are completed, the software computes the necessary parameters to be used for the test and displays the calculated values. The calculated parameters as well as the values used for the test configuration (entered by the user) are displayed. The user can analyze the calculated data and ensure that all acceptable. Some of the calculated parameters include trolley acceleration, trolley speed, motor pressure, motor speed, etc. If the test condition is outside the limit of the propulsion system, the software will display a warning message. The user can modify the test parameters until a satisfactory configuration is reached. This typically is only need when the system is close to its maximum capacity limit.

In second phase, the “CrashSoft control” software is used to execute the test. Similar to the phase 1, the software guides the user in systematic steps until the test is completed. Since the propulsion system is operated at high pressure during this phase, several checks are performed during each step to ensure that the test is performed safety and successfully. The steps of phase 2 are listed below:

Step 1: During the first step, the user is prompted for the test configuration file. By default, the last configuration file created is highlighted. The user can select the default file or choose a different file from a previous test. Once the file is selected, the program checks if all components of the propulsion system are turned on, operational, and ready.

Step 2: Once the file is selected, the software displays the test configuration and the corresponding computed propulsion system parameters. The status gages of propulsion system components are also posted. Additionally, a message window is displayed. All warning, errors, and standard messages are posted in this window. The user checks the test parameters, instrument gages, and message windows and if all okay the next step is started.

Step 3: The next step is start of the test sequence. During this phase, the software checks if all propulsion system components are turned on, functional, and ready. If all system checks are okay, the system displays the message “system checks finished”. If no warning or errors are displayed in the message window, the program prompts the user to press “yes” to continue

Step 4: The user is prompted if the trolley, the device used to connect vehicle to the propulsion cable, is ready to be moved to the start position. The user should ensure that no obstacles or personnel are on the way of the trolley, and press “yes”. During this step the trolley is moved slowly to the start position. The vehicle should then be connected to the trolley via the chain and hooks.

Step 5: In the next step, the program prompts the user if the propulsion system accumulators (pistons) are ready to be filled. If “yes”, the program activates the pump and oil is pumped into the cylinders. This process takes two to three minutes depending on the test vehicle speed and mass. The progress of the accumulator filling up is displayed and can be monitored via the pressure gage.

Step 6: Once the necessary pressure inside the accumulator is reached, the user is prompted if the facility ready and if it is okay to start the test. If “yes”, the valves are opened and the vehicle is pulled to the targeted speed.

Once the test is complete, the program collects and stores all propulsion system data. This data is used in the next phase to analyze the data.

The third phase consists of opening the collected data and analyzing the performance of the propulsion system. This is achieved through the “CrashSoft workshop” software. Once the software is started, the user is prompted to select a file. This file has “.dat” extension. Once the file is selected, the software loads all the data for visualization. The data consists of curves of computed (prior to the test) and actual measured data. The curves include trolley speed (similar to vehicle speed), trolley acceleration, motor speed, motor pressure, accumulator pressure, nitrogen pressure, etc. The software can be used to compare the calculated curves to the measured ones. The can be used for the pull tests as well as the actual tests to check that the calculated propulsion system curves mach the measured curves. Additionally, curves from different tests can be compared by opening multiple “.dat” files.

6.2- High Speed Digital Cameras

The original high speed photography system at FOIL was also upgraded. The 16 mm high speed film cameras were replaced by high-speed digital cameras. The digital cameras allow for an easier and quicker setup, faster processing and viewing of the test clips, and higher film resolution and quality.

Seven high speed digital cameras are currently available at FOIL to capture the test crash event.

All cameras were developed by “NAC Image Technology Corporation”. Four of the cameras are high resolution (1280x1,024) and three are standard resolution (640x480). Both camera types are capable of capturing 1000 frames per second at their highest resolution. Higher frame rates can be achieved at lower resolutions. Figure 4 shows one of NAC cameras used at FOIL.

Figure 4: NAC Memrecam K3 High Speed digital Camera

The digital cameras can be operated locally using the control panel located in the rear of the camera or remotely using a computer interface. During typical test setups at FOIL, the remote control option is used. The cameras are connected to a high-end personal computer through a fiber channel interface. The connecting interface consists of a master hub, slave hubs, a fiber channel card, fiber cables, and other cables. Figure 5 shows a typical camera connection diagram. Each camera is connected to a slave hub through the NAC cable. The slave hubs are connected to the master via similar cables. The master hub is connected to the fiber channel card located inside the computer. Once all cameras and hubs and connected the powered on, each camera can be controlled using the NAC FxLink Software. The software also shows the camera’s captured view allowing for real time picture adjutants.

Figure 5: Typical Camera Connections Setup.

The cameras recording can be started manually or using a trigger setup. The manual recording process is activated by pressing the record button on the camera control pane or from FxLink software. The camera will record at high speed rate for 1 to 8 seconds, depending on the resolution and frame rate setup, then stops. The recoding is stored in the camera memory for viewing or downloading to the computer. In all test setups at FOIL, the trigger recording option is used. In this option a pressure trigger is connected to the master hub. Few minutes prior starting the test, all cameras are set in “armed” mode. In this mode the cameras are continuously recording in a looped method (ie overwriting the earlier recording as the camera buffer is filled).

Once the trigger is activated, the cameras continue to record for a period of time then stops. This time period is user defined and is bounded by the camera’s settings (resolution, and frame rate).

The loop recording method allow for capturing the post impact even event as well a short period of the pre-impact. The zero point (the instant when the trigger is activated) is incorporated in the captured clip and set as frame number zero. All clip frames are then sequentially numbered using the zero frame reference with positive frame numbers indicating post-trigger and negative frame number indicate pre-trigger. Since all cameras are started using the same trigger, the zero point is identical in all capered views.

Details of the FxLink Software operation is describe in next section. More detailed description of the camera operation and maintenance are described in the NAC user manual [1].

6.3- Data Acquisition System

The original data acquisition system at foil was fully upgraded. The system was replaced by a TDAS PRO system made by Diversified Technical Systems. The system consist of TDAS PRO racks, TDAS PRO sensor input modules (SIMs), wireless interfaces, and the battery power source. A sample rack is shown in Figure 6-a, a sample SIM is shown Figure 6-b, and sample TDA PRO system installation is shown in Figure 6-c. A list of the TDAS components available at FOIL as shown is Appendix C.

The rack host the TDAS PRO SIMs. They come in 32 channel (four SIM slots) and 64 channel (8 SIM slots) configurations. The racks can be interconnected to create a higher channel count systems. It is designed to withstand 100+ G acceleration and can be placed inside test vehicles.

The rack is equipped with a built in rechargeable backup battery that enable safe operation in case of primary power loss. It has a 10BaseT ethernet interface allowing communication and data download to the PC control unit. The rack has a control panel with a key switch and connections for power/battery charger, ethernet, and close event signal trigger. The key switch is used to turn the data acquisition system on and off.

The TDAS PRO SIMs used at FOIL are stand-alone, eight channel data acquisition units.

Similar to the racks, the SIMs are designed to withstand 100+ G loading. The eight sensor input channels in SIMs are fully programmable and can be connected to the accelerometer, gyro, load cell, string pots, speed traps, and strain gages transducers available at FOIL. Each channel has an isolated excitation source, differential input signal amplified. Additionally, each channel is equipped with an automatic sensor identification system. This identification system feeds the unique transducer ID to the data acquisition software. This enables the software to use the appropriate parameters obtained from the transducer calibration data. This also ensures that the proper transducers are connected to the appropriate channels.

The battery source provides the data acquisition system with power on on-board setup. It enable the system to run without being directly connected to power outlet. It gives 12V power and it is connected to the TDAS pro rack.

The TDAS PRO data acquisition system is connected to the PC via direct or wireless ethernet connection. For the speed traps, the data acquisition is connected to the computer via direct ethernet cabling. For the on-board (vehicle) and on-ground (barrier/pendulum) data acquisition systems, a wireless interface is used to connect the data acquisition to the PC. For the wireless connection an ethernet box is connected to the rack and a wireless router is connected to the PC.

For a typical test, three different data acquisition systems are connected to the PC: direct ethernet for the speed trap system, wireless ethernet for the on-board data acquisition system, and a wireless for the on-ground (barrier) data acquisition system. The data collection systems are controlled by the computer software one at a time.

(a) Sample Rack (b) Sample SIM

(d) Speed Trap SIM

(c) Sample Data Acquisition System

Figure 6: Data Acquisition Components.

6.4- Motion Analysis Software

Motion analysis software is available at FOIL to extract data from the captured test clips. The software available is the “Movias Pro” developed by Motor Industry Research Association (Figure 7). The digital film clips are imported in the software and targets are auto-tracked to measure their motion. The measurements are collected in a reference frame that is defined based on a known distance in the digital test clip. Some of the extracted data include: trajectory, position, displacement, velocity and acceleration. Detailed description on how to collect use the Motion analysis software is available in the software manual [x]

Figure 7 Movias Pro Motion Analysis Software

6.5- Speed Measurement Systems

Pressure sensitive tape switches are the primary transducers used to measure a test vehicle’s speed. In this application, a series of five tapes switches are mounted sequentially on a thin mat and placed on the runway in the path of one of the test vehicle’s wheels. This switch arrangement is known as a “speed trap.” The switches are oriented laterally to the vehicle’s motion and are separated sequentially by a constant distance. As the tire moves over each switch, a series of sequential signals are sent to the data acquisition system. All data signals are recorded versus time. After the test, this data is processed using a speed trap software algorithm.

The distance between successive switches is entered into the software. The time between individual switch pulses has been previously recorded and stored in memory and, subsequently, transmitted to the computer’s memory. Because velocity is distance traveled divided by the time interval associated with travel over that distance, the software calculates three velocities, one for each successive two pulses. The software then averages the three velocities to determine the speed of the test vehicle. Typically a speed trap is placed in the runway immediately after the vehicle disengages from the tow trolley; a second speed trap is place immediately prior to the vehicle’s collision into the test article. In this manner, the speed of the test vehicle at release and instant of collision is determined.

Acceleration data can also be used to determine the test vehicle’s speed and to compare with and check the accuracy of the speed trap calculations. The test vehicle’s acceleration is recorded versus time; from the moment travel down the runway is initiated, during the collision event, until the vehicle comes to a complete stop. This acceleration data recorded versus time, is numerically integrated once to determine the test vehicle’s speed Because the initial speed of the test vehicle is zero, the vehicle’s speed at any point on the runway and into the collision event is directly determined. In this manner, the speed at disengagement from the propulsion system and at the instant of collision can be determined independently and compared with the speed derived from the speed traps.

In a somewhat similar manner, the speed of the test vehicle can be determined from the digital camera data. The digital cameras are typically focused on the vehicle’s collision into the test article. Using the motion analysis software, the displacement of the test vehicle during the collision event is determined. This displacement data is then numerically differentiated, once with respect to time, to determine the test vehicle’s speed at the instant of collision and into the collision event. In this manner, the speed at the instant of collision can be independently determined and then compared with the speed derived from the speed trap. Less accuracy is associated with this speed determination because, as previously noted, the differentiation process is a mathematically roughening calculation. That is, numerical errors are exaggerated during this calculation.

6.6- Data Transducers

Accelerometers

Over 40 accelerometers are available at FOIL. A list of these accelerometers is shown in Appendix D. These accelerometers are used to measure vehicle or barrier accelerations during the impact. The most commonly used accelerometer at FOIL is the ENDEVCO Model 7265AM3 (see Figure 8a). The ENDEVCO Model 7265AM3 is a low mass, undamped piezoresistive accelerometer designed with a miniature receptacle to allow for detachment of the cable assembly. This accelerometer is designed specifically for the automotive crash testing industry and meets SAEJ211 specifications.

The accelerometers are typically connected to the vehicle via Aluminum blocks (Figure 8b).

They are typically mounted in unidirectional configuration, hence measuring acceleration in one direction or the acceleration during the impact. These accelerometers are connected to the TDAS Pro data acquisition system.

(a) 7265AM3 (b) Aluminum Block (c) Aluminum Block (d) Redundant Accelerometer Single Axis Tri-Axle configuration

Figure 8: Accelerometers

Load Cells

More than 24 load-cells are available at FOIL for measuring the impact…