Ergo Lab

The 6th Annual Applied Ergonomics Conference in Dallas, TX was a big success, the 7th Annual Applied Ergonomics Conference will be held in Orlando, FL from March 8-11, 2004.

To aid in the educational and research programs in Ergonomics and related fields, the Industrial Engineering Department maintains several extensive laboratories:

a. The General Ergonomics and Human Performance Laboratory is used for both undergraduate and graduate experimentation and demonstrations. It includes equipment for performance assessment (reaction time, performance time, learning, ... etc.).

b. The Biomechanics Laboratory includes anthropometric calipers, strength measurement devices, skin fold calipers, an anthropometric chair, hand tool investigation and evaluation apparatus, body segment parameter determination equipment, and a push-pull dynamometer. In addition to the maximum isometric strength measurement capability, the Biomechanics Laboratory also provides the capability of measuring dynamic strength (concentric and eccentric contractions using a Cybex II isokinetic dynamometer). The Biomechanics Laboratory also includes a lifting facility for the determination of lifting capacity of males and females, and interchangeable force plates. High speed 16mm motion picture cameras are available for research efforts. Biomechanical file analysis is facilitated through the use of Science Accessories Corp. digitizer with the sonic pen or cursor that is inputted into the IBM computer system. An instrumented treadmill is used to monitor ground reaction forces in consecutive steps. A 6-camera real time motion analysis system has been added to monitor human 3D motion more efficiently. In addition, a virtual reality (VR) racetrack is under construction. The VR system provides various realistic hallway scenes as a subject walks along an oval racetrack. The track is 4 feet wide and 70 feet in circumference sheltered by a fall arresting robot.

c. The Work Physiology Laboratory includes bicycle ergometers, a programmable Collins treadmill to provide a wide range of loading profiles, Beckman Oxygen Analyzer, sampling gasometers, and readout equipment in the form of Beckman recorders, Sanborn recorders, and Physiographs. In addition, the laboratory includes a Beckman Metabolic Measurement Cart that can be used for the measurement of oxygen consumption/carbon dioxide production and basic pulmonary functions and an Ambulatory monitoring Ind. Oxylog for field oxygen consumption analysis. The work physiology laboratory also includes equipment for measuring blood pressure manually or automatically and several pieces of equipment for measuring, recording and quantifying EMG signals and recording and quantifying EMG signals and recording EKG and heart rate during rest and work. Heart rate, body temperature and other physiological parameters can be recorded from an ambulatory subject using an AMI Medilog.

d. The Heat and Cold Stress Laboratory includes an environmental chamber with temperature range of 30 to 115 degrees F. The environmental chamber is 16 x 16 x 11 feet high and therefore can be used for single and group experiments. In this laboratory, additional equipment to measure heat stress is available including an air velocity meter, hygrometers, wet, dry, and black globe thermometers, and Reuter Stokes WIBGET heat stress monitors.

e. The Human Factors Interface Simulation Laboratory is a new capability, which is currently being added to the department's extensive human factors facilities. The main feature of the laboratory is the Tele-robotics and Tele-operations system (TTS). The TTS is based on a Silicon Graphics high-speed computer image generator. Specifically, a Silicon Graphics 4D-85, which provides 16.7 Mhz, 13 MIPS, 400K vector generation and 90K Polygon generation, necessary for the real-time dynamic simulation of complex, color, high image quality, out-the-window visual scenes simultaneously with real-time updates of end-effector parameters on experimenter specified control/display suites.

In addition to these special laboratories where Ergonomics investigations are performed, there are other laboratories used for other programs within Industrial Engineering. These include the Manufacturing Science Laboratory and the Metrology Laboratory. The department also maintains supporting facilities in the form of metal, wood, and electronic workshops where instrumentation for research and teaching can be manufactured and serviced. A photographic facility is also maintained by the department in support of the research and teaching activities.

The word ergonomics comes from the Greek ergo (work) and nomos (rules, law). It can be simply described as the science that fits the job or activity to the person who is doing the job or activity. That may seem like a common sense statement, and in many ways it is. People have been practicing ergonomics ever since the first person fashioned a tool or devised a better method to do something that was previously, slow, difficult or painful to accomplish. In a very real sense, all people (not just designers and engineers) practice ergonomics to some extent.

For instance, the famous engineer and philosopher Leonardo Davinci could easily be considered an early ergonomics practitioner. His detailed study of the human body aided him in the design of machines that were to be used by people. See the sketch below:

The development of ergonomics as a special effort has arisen from the expanding knowledge about the complexity of human capabilities and limitations and the increasing need to ensure the safe, efficient, interaction of people with products and environments. Stated simply, ergonomics or human factors is focused on designing products and systems for human use. Inherent in this design process is the goal to design systems which optimize system performance, safety, and user satisfaction. Individuals who offer their services in the field of ergonomics are typically referred to as Professional Ergonomists or Human Factors Professionals. If you are interested in learning more about professional certification in ergonomics. Visit http://www.bcpe.org/ Texas Tech has a long tradition of educating students who go on to become leaders in the ergonomics field. Contact the Industrial Engineering department for more information regarding the career paths of Texas Tech alumni.

Be sure to see details of the Fitt's Law experiment performed by some of our undergraduate students on NASA's KC-135 aircraft in August!
Texas Tech NASA Project (click here)
Fitt's Law describes the manner in which the speed and accuracy of moving an object are determined by constraints of the movement task.

The ergonomics laboratory has a number of exciting new projects underway. For example there are multiple projects dealing with applications of Virtual Environments or 'Virtual Reality' to improve safety, health, and productivity.

This project involves the use of a partial gravity suspension simulator to determine interactions between loading and variants of the optic flow field in order to aid astronauts as they transition from a microgravity environment (orbit) to the Earth's gravitational field near the Earth's surface (also called 1G). Visit this site often to see updates of the partial gravity simulation studies.

The picture above is a CAD model showing the main features of the partial gravity simulator. See how we constructed the simulator in the photos below.

See Jeff testing out the partial gravity simulator. Our ability to achieve nearly constant tension levels throughout a wide vertical travel range is very unique. No other simulator uses our innovative design.

Actually, it's a lot of fun too! Our subjects are getting to do lot's of this locomotion so that we can better understand the adaptation of postural control mechanisms.

Installation of the virtual environment projection system was the final major component for making the simulator operational.

In order to make full use of the 6 by 8 foot opening in front of the partial gravity simulator, a special projector stand was created to allow for horizontal mounting of the projector. The projector can be configured in the rotated position shown or in a table mount position. Using the projector in this non-traditional orientation requires us to design our software with the rotation incorporated. The virtual environment created with such a large projection system provides an exciting immersive experience for the subject and a rich test bed for locomotion research.

This side view of the partial gravity simulator reveals the 6 camera Motion Analysis system that is being used to collect kinematic data for our subjects. Kinematic data is the data that documents the limb positions and patterns of a subject over time.

Be sure to check this site often for updates showing subjects in action within the simulation environment!

The partial gravity simulator is being used to help discover the ways in which the goals of the person (to maintain balance, move efficiently, etc.) and environmental constraints combine to enable successful standing or locomotion both at 1 G (gravitational acceleration close to the Earth's surface) and in altered gravitational environments. Modeling efforts are underway to generate improved simulations of human movement under a variety of environmental conditions. The equation above, borrowed from Newtonian mechanics, highlights the stiffness, viscosity, and acceleration aspects of human locomotion models. Our approach to modeling human motion involves several steps:

This research is a natural extension of the many human movement investigations and simulation efforts that have been conducted at Texas Tech's Ergonomics Laboratory. This project represents the first time that a partial gravity suspension simulator is being coupled with sophisticated computer generated imagery to create such a compelling and environmentally challenging virtual environment. If you have an interest in learning more about these innovative research techniques for studying postural control, you may contact Dr. Simon Hsiang, or Jeff Brewer through the Texas Tech IE department.

We are able to create a wide array of virtual environments for our subjects to 'walk through'. Give it a try!

If you live near Lubbock and have an interest in participating in the upcoming partial gravity experiments, please contact the IE department at 742-3543 or Jeff Brewer directly at 785-4108. Pilot studies are underway, but more subjects are needed so be sure to contact us!

This project examines the visual perception component that may contribute to whether a person slips or falls when they encounter a slippery surface. Texas Tech has been one of the premier institutions for examining slips and falls for a number of years. The emphasis of our research is moving beyond the detailed description of the slip/fall event and looking closely at the factors which comprise the person's preparation process before a slip or fall occurs.

Many factors contribute to the probability of occurrence of a slip or fall. The conjecture of this study is that the degree of human perception of the surface slipperiness is among those factors. In addition, it is hypothesized that the surrounding environment (ceiling height, room width and orientation, lighting intensity and arrangement, etc.), and not only the floor surface, contributes to the human perception of the surface slipperiness. Due to the impracticality of conducting such a study with many environments, the researchers studied the applicability of performing the tests in a virtual environment. In a dark and completely enclosed space (2m´ 2.5m ´2.5m), the subjects were presented with graphical images of different environments on a computer monitor and asked to evaluate the slipperiness of the surfaces in the images. The subjects were made to believe that the actual floor surface on which they were standing was changed with the changing of the images, and were also asked to evaluate the slipperiness of the actual floor. There was a noticeable difference in the subjects’ perception of the floor slipperiness throughout the trials regardless of the fact that the floor was never changed. The use of virtual environments is therefore verified as an accepted method of slips and falls testing in a limited laboratory environment.

Do you live close to Lubbock and have an interest participating in slip/fall research? If so, please contact the IE department (742-3543). We are currently conducting a slip/fall study and need more subjects ages 18 - 80. If you happen to be over 80 years of age and in reasonably good health (can walk well) you are welcomed to participate.

This figure shows the key components of our slip/fall track and arresting system that is used during many of our slip fall experiments. Two of the experiments planned for the Spring 2001 semester will use this apparatus.

¨ To accomplish this: (1) reduce step frequency, (2) shorten step length, and (3) lower the center of mass of the body.

- Why is the gait strategy mentioned above useful for adapting to the slippery surface?

- Are there any differences in adaptation gait strategy between younger and old people?

¨ In order to investigate this topic, we must know what human gait is, how the human controls body segments, and how the human interacts with the environment.

¨ We are interested in (1) the dynamics of human movements and (2) how to apply knowledge of human dynamics to help people.

If you would like more information regarding the current slip/fall research, please contact Woo-Hyung Park

Over the last 60 years, investigations involving slips and falls have been conducted in order to better improve the understanding of the causes, mechanics, and prevention of falls. Nevertheless, information learned regarding slips and falls remains very limited. Researchers have, for the most part, studied slips and falls from a mechanical standpoint. Their research thus far has focused on studying slip resistance using a measure of friction known as the coefficient of friction (COF) as well as other topics closely related to COF such as COF measuring devices and shoe and floor material. This includes numerous studies focused on investigating the relationship between slipping and the shoe/floor material interface.

This research involves identifying the relationship between the visually perceived information of the surrounding environment and the biomechanical adjustments made by a human in motion in order to adapt to the visually perceived environment. The hypothesis used is that humans change their gait pattern in order to accommodate for the environment that is perceived by processing visual information while the perceived environment and the actual environment may not necessarily be identical. Below are several hallway scenes which may have different effects on a person's perception of floor slipperiness.

Biomechanical modeling has always been a strong focus of the Texas Tech Ergonomics Program. An description of biomechanical modeling and a recent biomechanical study are listed below.

Biomechanics is the study of the effects and control of forces that act on or are produced by living tissue. Its major classifications are (1) sports biomechanics; (2) clinical biomechanics (including cell, tissue, dental, cardiovascular, respiratory, orthopedic, rehabilitative, spinal, gait biomechanics); and (3) occupational biomechanics. The most common variables investigated in biomechanical analysis are

Biomechanical models are frequently used to (1) summarize a body of information; (2) divide a complex process into unitary functions; (3) divide a complex physiological process into identifiable steps; (4) provide insight into structure-function relationships; (5) summarize one system in order to understand the implications for another system with which it interacts.

Generally, there are three components in a model: the inputs, the embedded mechanism and the outputs. Given the inputs and outputs, a system identification model is designed to find the embedded mechanism. Given the outputs and the embedded mechanism, a control model is designed to find all the plausible input signals. Given the inputs and the embedded mechanism, a simulation model is designed to find all the possible outputs. No model can represent reality with full accuracy. Models are abstractions; as such, they are necessarily flawed. By nature, models are either overly simplified or overly complicated. The complexity of a model depends on the objectives of the model. A justifiable biomechanical model should have (1) minimal number of variables (e.g., principle of parsimony), (2) sufficient explanatory variability, (3) repeatability, (4) robustness, and (5) validated outcomes.

The general objective of sports biomechanics is maximization of athletic performance. Biomechanical techniques can be applied clinically for the goal of reducing abnormality. The objective of occupational biomechanics is the examination of the physical interaction of workers with their tools, machines, and materials so as to maximize worker’s performance while minimizing the risk of musculoskeletal disorders. The most reported work-related injuries of musculoskeletal disorders are (1) lower back pain (LBP), (2) injuries related slips, trips and falls, and (3) repetitive motion disorders of the upper extremities. These disorders have a multifactorial pathology and onset can be acute (e.g., due to overexertion) or chronic (e.g., due to overuse).

Among the three common areas of musculoskeletal disorders, LBP has the most complex nature, and has the highest cost associated with disability. For years, two basic questions have remained elusive -- (1) is the pain real? (2) where is the pain coming from? Clinical studies suggest that the origin of LBP can range from the discs (herniation/disruption) to the facets, from the ligaments to the muscles. The anatomic levels involved range from the L3/L4, the L5/S1 to the sacroiliac joint. Thus, the pain could be from any location of the lower back area. This area is compact and redundant with various muscles and ligaments, and serves as the bridge between the upright torso and the lower extremities. During physical activities, such as lifting, some muscles act as prime movers or coactivate with other muscles (e.g., psoas and abdominis) to provide stiffness. With very limited mechanical advantage both mobility and stability are achieved. Since the structure performs an important role in transferring the forces and the bending moments from the upper torso to the lower extremities, it is under tremendous stress. Three types of questions are frequently asked by biomechanical practitioners:

While some psychologists suggest using the psychophysical approach to determine the maximum acceptable weight for lifting and other manual materials handling, the conventional biomechanical approach is the reduction of spinal loading. This can be achieved by decreasing the load or the moment imposed by the combination of the body and the load. Based on the moment-reduction strategy, several guidelines on lifting techniques have been developed, such as:

Below is a brief description of a recent biomechanical modeling study performed in the ergonomics lab:

Three Different Lifting Strategies for Controlling the Motion Patterns of an External Load

Coordination of various components of the human body during the course of lifting are very complex and difficult to control. This study hypothesized that strategies used to control the motion patterns of the external load may be applied to control coordination and also to control the level of compressive force on the lumbosacral joint. A simulation of lifting based on the optimization approach was introduced to generate three classes of unique dynamic motion patterns of the external load directed by three different objective functions. The first objective function was to maximize the smoothness of the motion pattern of the external load. The second objective function was to minimize the sudden change of the center of gravity of the body-load system. The third objective was to minimize the integration over time of the sum of the square of the ratio of the predicted joint moments to the corresponding joint strength during the course of lifting. Eight subjects were recruited to perform 40 lifts using each of the three optimal motion pattern of the load. Compressive forces on the lumbosacral joint were computed and compared. The data showed with statistical significance that subjects using the motion patterns of the external load suggested by the first objective function had the lowest compressive force peaks. Thus, this study has satisfied two goals: (1) it indexed and synthesized three motion patterns of the external load by three biomechanically unique objective functions, and (2) it established the association between the spinal loading and the control of the motion patterns of the external load during lifting.

The figures above illustrate the type of lifting task performed. Contact Dr. Simon M. Hsiang for further information regarding this study.

This project was completed in the spring semester of 2001 and involves comparing backpack load carrying with flexible pole carrying. This research is an extension of research performed in the early 1990's. Have you ever seen a person carrying two loads - one at each end of bamboo pole? Have you ever wondered whether this method is better than the typical 'backpack' method of carrying loads in the US and other Western countries?

Carrying loads with flexible poles is common in many parts of the world. Is this type of load carrying superior to using a backpack that is more rigidly attached to the body? If so, it is important to specify the situations in which flexible pole carrying can be advantageous and to determine what lengths of flexible poles are most desirable. To investigate these questions an analysis of gait parameters, shock transmission, oxygen consumption, load trajectory control, don and removal techniques, and subjective opinions was conducted. Four subjects (two male, two female) ran at a constant 3.0 m/s carrying a load equal to 15% of their body weight either in a backpack or using a flexible pole apparatus. Three lengths of flexible poles were used: 3.6 m, 3.0 m and 2.5 m. Subjects preferred to use the short and medium poles instead of the long poles. Impact forces on the shoulders were significantly greater for the backpack condition. Oxygen consumption increased by 12% to 20% above the unloaded running condition with each carrying method. This data (given the short familiarization sequence and individual differences) supports the findings in previous research showing oxygen consumption increases in direct proportion to the mass supported by the muscles in trained subjects. Although, it appears that the length of the compliant poles is critical for ensuring that load-carrying safety and comfort is superior to the backpack method.

The table above describes various characteristics of the 4 subjects, subjects 1 and 2 were in relatively good physical shape and subjects 5 and 6 were in very good physical condition.

Dependent Variables

Experimental Factors

This study has closely examined the differences between carrying a load in a backpack (typical in Western countries) and carrying loads suspended upon poles of varying lengths (typical in Far Eastern countries). The results do not conflict with and generally support previous research which discovered that carrying loads on compliant poles does not reduce the energy cost of load carrying though they do appear to reduce impact forces on the body. Although, the length and compliance of the poles along with the amount of load carried are very important for realizing these reduced impact forces. Also, this study has examined in more detail the aspects of load control (via qualitative and subjective data) to understand the occasions when compliant pole carrying should be considered superior to backpack carrying and vice versa. Overall, shorter poles were preferred by the subjects here to enable greater load control and reduced shoulder forces. It is recommended that compliant poles be considered helpful when load levels are high (less stooping to don load), terrain elevation does not change rapidly, wide open areas are available, loads are not very fragile, rapid changes in direction, orientation, and speed will not be required and subjects are familiar with this technique.

With regard to further research, the frequency characteristics of compliant pole motion should be investigated further, along with the ways in which anthropometric differences (subject mass - magnitude and composition) influence stride length and other characteristics of gait in running subjects. Investigating these items at the same time may provide further insights and improve the ability to model running gait using the mass, spring, and damper approach. Improved models of both walking and running gaits may reveal clues as to how people such as select African women can carry loads with little or no energy cost.

*For a more complete discussion of the project results click here. To get a complete copy of the study, please contact Jeff Brewer or Dr. Simon Hsiang.

Virtual reality (VR) systems promise to deliver dramatic improvements to areas such as training, rehabilitation, and entertainment. Success in each of these areas is being realized by VR systems, although the reports of motion type sickness (simulator sickness) and disorientation are still prevalent among users. What is it that makes a VR system effective and pleasing for the user? This project examines the relationship between various optic flow presentations and the effect they have on a 'system user' who is attempting to synchronize their treadmill walking speed with the visual stimulus.

Optic Flow can be defined as the relative movement of points across the visual field as a person moves through an environment. In other words, it is what you see as you move. Interestingly, as we move through the world our visual system is very effective at using elements of the optic flow field to determine which objects are stationary and which objects are in relative motion with the environment.

This experiment involves a subject on a treadmill viewing a simple computer generated optic flow pattern represented by small circular points of light. The density (number of light points) and the rate at which dots appear to move towards the observer are manipulated. The subject's goal is to synchronize their treadmill speed with their interpretation of the optic flow speed. A number of interesting findings have resulted from this study.

Above is a computer model of the apparatus set-up (right rear section removed). Below is a representation of the visual displays and the experimental factors.

Conducting this experiment gave some of our students experience with the way optic flow information can be used by the body to provide relatively consistent mapping of a treadmill walking speed to a particular optic flow presentation. The main finding in this study was that optic flow density and expansion rate did have a positive and linear influence on the treadmill speeds chosen by subjects at the 'right' speed matching the optic flow field with their haptic and proprioceptive sensations.

Sixty randomized presentations of optic flow during 3-4 hour testing sessions for six subjects confirmed the positive and linear relationship. One interesting finding included the fact that a strong feeling of self-motion was induced for 5 of the 6 subjects. That is somewhat surprising given the small visual angle subtended by the imagery (15 degrees). It is thought that the radial optic flow pattern and the extremely dark surroundings enabled such a strong illusion of self motion when using a relatively small (21 inch along diagonal) monitor.

Medication errors make up a large part of the number of errors that occur in the healthcare system. Studies have revealed that on the average there are 1-2 medication errors for every ten prescriptions that are filled. Deficiencies in information underlay many of these errors. These deficiencies in information relate to similar labeling and packaging, look-alike brand names, and sound-alike brand names. This research has focused on the information that is contained in the actual words of the drug names, and how the format of the text of the drug name is portrayed on the drug container and the prescription label. Different formats have been created that break up the drug name into parts that help identify the dissimilarities between drug names. For instance, the formats such as “LEVOXINE”, “LEVOXINE”, and “LEVOXINE” use large fonts and color to break the drug names up. These different formats have been used in sorting tasks in which pharmacists must sort stacks of prescription labels into slots labeled with the drug name. The speed at which prescription labels can be sorted and the number of errors associated with the placement of incorrect prescription cards into the wrong slot have been quantified. It is the goal of this research to identify the format that produces the quickest sort time and the fewest number of errors with the least amount of variation between subjects. It is hoped that this research will help identify ways to reduce medication errors.

Here you can see Aaron discussing the apparatus he built for conducting the prescription label sorting task.

The data from this research show that using medication labels with the format “LEVOXINE” produce the fewest number of medication errors. With this format yellow highlight is used to breakup the drug name. The data also show that using medication labels with the format “LEVOXINE” produce the fastest sort times. With this format red text is used to breakup the drug name. The use of yellow highlight had the smallest standard deviation for medication errors, while the use of red text had the smallest standard deviation for sort time. The use of yellow highlight and red text in medication labels both show promise in reducing the number of medication errors and increasing the efficiency of pharmacy operations.

The results of this study can be applied to the current operations of pharmacies. In hospital pharmacies medications are pulled from bins that are marked by labels containing only the medication name. When these bins are stocked, the medication name is the only piece of information that is used to identify the correct bin. Also, when medications are obtained from the bins, the label is again the only piece of information that is used to identify the correct bin. The results of this study could be used to redesign the labels of bins, which contain medications that have names similar to other medications. Pharmaceutical companies may also use the information from this study to redesign the package labels of medications that have names similar to other medications. Any pharmacy operation that uses the medication name to identify a medication could benefit from the redesign of medication labels based on the information from this study.

This research was meant to help identify ways to reduce the number of medication errors. It was identified by this study that the use of different sized text and color in the design of medication labels does help to reduce the number of errors. Further studies may look closer at the sort times between yellow highlight and red text label designs. Also, further studies may identify the amount of contrast that is needed when using yellow highlight or red text in medication labels. Research on the location of the medication word on the medication labels may provide relevant information on the reduction of medication errors. New information is the key in understanding and preventing medication errors.

The medication error research study was performed by Aaron Ross - a recent graduate of our Industrial Engineering Master of Science program. Aaron's specialization was in the area of Human Factors and Ergonomics. If you have questions concerning his research project, you may contact him by email, Aaron Ross.

Fred Schneider; machinist/laboratory technician
Graduate of German Trade School
Over 20 years of experience as a machinist
(aircraft components, precision tooling, molds, ... you name it,
he has probably built it)

Texas Tech University, 1999 –
Seoul National University (Korea), M.A. (Psychology), 1997
Seoul National University, B.A. (Psychology), 1988
Korea Air Force Academy, B.S. (Industrial Engineering), 1983
Korea Air Force, 1983 – 1997

Current Research Area: Investigating the dynamics of human movements in slip and fall situations in order to (1) investigate the effects of anticipation and the adaptation mechanisms people use when interacting with their environment, (2) build a mathematical model to simulate these mechanisms, and (3) find the difference in the above mechanisms between younger and older people.

Ergonomist for Raytheon, McKinney, TX, 1998-2000
M.S. from Texas Tech, 1997
B.S. from St. Mary's University, San Antonio, 1996
Engineering Co-op for Bausch & Lomb, 1993-1996
United States Marine Corps Reserve, 1989-1997

Specialties: Occupational Biomechanics, Ergonomic Program Development and Implementation (for office and manufacturing environments), Industrial Ergonomics Training, Design and Implementation of man-machine systems to enable safe and efficient manufacturing processes (complex material handling systems, hand tools, process control devices, computer aided assembly methods, etc).

Current Research Area: Investigating postural control mechanisms used to enable stable standing and locomotion following perturbations induced by simulated partial gravity environments.

Goal: Discover critical environmental cues that are used by the body (either in open-loop or closed-loop fashion) to maintain stable dynamic postural control and allow for rapid adaptation to acceleration changes in a simulated partial gravity environment. These cues will be used to generate a dynamic postural control model that can be used to explain adaptation responses (for additional information see Current Projects section above).

Hobbies: Sailing, rock climbing, running, swimming, mountain biking, playing classical guitar, photography

These links are a mixture of university web sites and industry web sites that describe current research efforts, products, and services available to the ergonomist or human factors professional. The first link will introduce you to the human factors program in the psychology department at Texas Tech. At the bottom of the list are links to the Human Factors and Ergonomics Society and the Occupational Safety and Health Administration - where you can find information regarding the new Ergonomics Standard. The last web site on the list provides an amusing look at a number of products that were poorly designed for human use.

June, 1963 Physiological Investigation Of Performance Rating For Repetitive Type Sedentary Work," Robert R. Manuel. Advisor: M.M. Ayoub

June, 1963 “The Investigation Of Time, Distance, Weight Relationships For Certain Moves,” Billy P. Smith. Advisor: M.M. Ayoub

May, 1964 “An Optimal Design For A Foot Activated Lever Mechanism,” John Ensdorff. Advisor: Richard A. Dudek

May, 1964 “The Effect Of Vibration On Certain Psychomotor Responses,” David E. Clemens. Advisor: Richard A. Dudek

May, 1964 “An Investigation Of The Interaction Of Light And Sound Variables On Reaction Time,” Raymond R. Medeiros. Advisor: M.M. Ayoub

May, 1964 “Biomechanics Of Lever Operations,” Patrick F. Noud. Advisor: Richard A. Dudek

May, 1964 “An Investigation Of The Metabolic Cost Of Tasks Involving Isometric Pull,” Michael J. Petruno. Advisor: Richard A. Dudek

May, 1964 “Investigation Into The Effect Of Intermittent Noise Of Constant Periodicity vs. Random Periodicity On The Performance Of An Industrial Task,” Nevin E. Fornwalt. Advisor: M.M. Ayoub

August, 1964 “The Determination Of An Optimal Work Area Envelope In The Horizontal Plane,” Harold M. Goodwin. Advisor: Richard A. Dudek

May, 1965 “A Biomechanical Investigation Of Static Pull With Constant Shoulder Torques,” Morton B. Berman. Advisor: Richard A. Dudek

May, 1965 “Optimal Three-Dimensional Work Place For The Seated Worker,” Richard H. Wyatt. Advisor: M.M. Ayoub

May, 1966 “An Analysis Of The Center Of Gravity Of The Arm During Certain Simulated Industrial Moves,” Virgil B. McElhannon. Advisor: M.M. Ayoub

May, 1966 “Effect Of Pace On Velocity And Acceleration Patterns Of Body Member Motions in Space,” Baldev G. Raheja. Advisor: M.M. Ayoub

May, 1966 “Measurement Of The Incremental Volume Of The Upper Arm Under Dynamic Conditions,” George A. Schultz. Advisor: M.M. Ayoub

May, 1966 “Experimental Determination Of An Optimal Foot Pedal Design,” Donald J. Trombley. Advisor: M.M. Ayoub

May, 1966 “The Relative Placement of Control Stimulus-Display Panels With Respect To The Operator And Their Effect On Performance,” Sidney W. Vanloh. Advisor: M.M. Ayoub

August, 1966 “The Effects Of Low-Level Vibration On The Performance Of A Sensory Input--Physical Response Task Requiring A Decision Factor,” Richard L. Bush. Advisor: E.R. Tichauer

August, 1966 “The Sensitivity Of Sampling Inspection To Inspector Error,” Allan S. Davis. Advisor: M.M. Ayoub

August, 1966 “An Investigation Of The Effect Of Work Surface Height And Operator Size On Physiological Cost In An Assembly Operation,” Robert D. Hastings. Advisor: E.R. Tichauer

June, 1967 “A Kinesiological Evaluation Of The Performance Of The Gloved And Ungloved Upper Limb During Manipulative Handling Of Small Objects,” Robert C. Banasik. Advisor: E.R. Tichauer

June, 1967 “Effects Of Lighting And Background With Common Signal Lights On Human Peripheral Color Vision,” George M. Colton. Advisor: Richard A. Dudek

June, 1967 “An Investigation Of The Effects Of Posture And Rest Periods On The Performance Of An Inspection And Positioning Task Performed Under Stereo Magnification,” John W. Douglass. Advisor: E.R. Tichauer

June, 1967 “An Investigation Of The Effects Of Two Types Of Inspector Error On Sampling Inspection Plans,” Kenneth A. McKnight. Advisor: M.M. Ayoub

June, 1967 “A Kinesiological Evaluation Of Parallel Versus Symmetrical Patterns In Simultaneous Hand And Arm Motions,” Fred G. Reichard. Advisor: E.R. Tichauer

June, 1967 “A Study Of Factors Affecting The Move And Position Elements Of A Small Component Assembly Task,” Robert N. Roberts. Advisor: E.R. Tichauer

June, 1967 “Peripheral Depth Perception At The Work Place,” Fred Rochez. Advisor: E.R. Tichauer

June, 1967 “Kinesiological Analysis Of A Simple Assembly Task,” Willie R. Wall. Advisor: E.R. Tichauer

August, 1967 “The Effects Of Noise Variables Of Reaction Time And On Sensorimotor Performance,” Walter L. Clark. Advisor: M.M. Ayoub

June, 1968 “A Behavioral Analysis Of An Assembly-Line Inspection Task,” Richard V. Badalamente. Advisor: M.M. Ayoub

June, 1968 “A Study Of Depth Perception Within The Binocular Peripheral Field Of Vision,” Richard H. Crockett, Jr. Advisor: M.M. Ayoub

June, 1968 “A Biomechanical Investigation Of The Possibility Of Relating Static And Dynamic Work By Means Of A Common Parameter,” Tarek M. Khalil. Advisor: M.M. Ayoub

June, 1968 “Electromyography And Optimum Handle Size,” Peter Lo Presti. Advisor: M.M. Ayoub

June, 1968 “The Effects Of Noise Variables On Reaction Time,” James C. Scott. Advisor: Jerry D. Ramsey

June, 1968 “An Elemental Component Decomposition Of A Simple Assembly Task,” John B. Sotman. Advisor: M.M. Ayoub

June, 1968 “Numeral Identification In The Peripheral Field Of Vision As An Aid To Work Place Design,” Hirum E. West. Advisor: Jerry D. Ramsey

August, 1968 “The Effects Of Colored Lighting, Illumination Intensity Level, And Color Of Workplace On A Fixed Inspection Task,” Robert W. Tedder. Advisor: Jerry D. Ramsey

May, 1969 “Human Factors In The Design And Operation Of Handwheel Controls Used In A Dynamic Manual Task,” Larry B. Jordan. Advisor: Jerry D. Ramsey

May, 1969 “Quantification Of Human Motion By Stereo-photogrammetric Technique,” Mahmoud A. Ayoub. Advisor: Jerry D. Ramsey

May, 1969 “A Study Of The Effectiveness Of A Vibrotactile Warning Signal During Whole Body Vibration,” George A. Guthrie. Advisor: Jerry D. Ramsey

June, 1969 “An Electromyographic Study Of A Rotary Task,” Edward Karnasiewicz. Advisor: Jerry D. Ramsey

August, 1969 “The Effect Of Audio-Visual Loading On Vibrotactile Signal Detectability,” Gary D. Luker. Advisor: Jerry D. Ramsey

August, 1969 “A Correlation Between Angular Impulse And Ventilation Rate During A Simple Movement Of The Upper Limb,” Amr K. Mortagy. Advisor: M.M. Ayoub

December, 1969 “An Investigation Of The Effect Of Inclination Of The Tilt Seat Stool On The Physiological Cost,” D.J. Vijayadeva Murthy. Advisor: M.M. Ayoub

May, 1970 “Strength Of Pronation And Supination At Selected Positions In Space,” Rajinder K. Chhabra. Advisor: M.M. Ayoub

May, 1970 “Estimation Of Ventilation Transients Of Respiratory Control System,” Pradeep Sinha. Advisor: Jerry D. Ramsey

May, 1970 “Optimal Skeletal Configuration Under Static Pushing And Pulling Tasks,” Grandai S. Srinivasan. Advisor: M.M. Ayoub

August, 1971 “The Feasibility Of Utilizing Lateral Photocells In A System For Recording Human Motion,” Eugene N. Davidson. Advisor: M.M. Ayoub

August, 1971 “Effects Of Interior Handle Design Parameters Upon Evacuation From Automobiles,” Eugene T. Dorneman. Advisor: Jerry D. Ramsey (Missing)

August, 1971 “Development Of A Second-Order Model For Hand Motion,” Sanaa I. Taraman. Advisor: M.M. Ayoub

August, 1972 *”A Study Of Man's Strength Relative To The Physical Requirements Of Lifting Tasks,” John W. Storment. Advisor: M.M. Ayoub

March, 1973 *”The Problems Of The Man-Microscope Interface In The Industrial Environment,” Harvey C. Foushee. Advisor: M.M. Ayoub

August, 1973 *”Lighting In Industry,” Horace Lehneis. Advisor: Richard A. Dudek

August, 1974 “Lifting Capacity As A Function Of Operator And Task Variables,” Fereydoun Aghazadeh. Advisor: M.M. Ayoub

December, 1974 “An Evaluation Of Existing Occupational Noise Standards,” Kenneth M. Bisbee. Advisor: Jerry D. Ramsey