Online. The Computerized Resistive Exercise DynamometerPublished on Friday, November 8, 1996 by Gideon Ariel
Computerized Resistive Exercise DynamometerThe
Gideon B. Ariel, Ph.D. and M. Ann Penny, Ph.D.
1. IDENTIFICATION AND SIGNIFICANCE OF THE INNOVATION
The goal of this proposal is to develop a computerized, feedback-controlled, portable, battery-powered, hydraulic dynamometer which can be used in normal, reduced-g, and zero-g environments. The proposed device will provide a closed-loop feedback system to measure and control various muscular strength parameters. The innovativeness of this device includes (1) the ability to measure muscular strength without the limitations imposed by traditional weight-related devices; (2) computerization of both the feedback control feature, allowing adjustment of the device to the individual rather than the individual accommodating the device, and customization of the diagnostic and exercise protocols with data storage capabilities; (3) low-voltage, (4) portability, and (5) compactness. The relevance of the proposed equipment for NASA lies in its ability to evaluate astronaut strength and endurance levels as well as to design and follow appropriate exercise protocols in all gravitational environments. Data can be stored for later evaluation and for use in conjunction with other medical or physiological assessments in the continual effort to identify and counter the deconditioning caused by microgravitational conditions.
Physical fitness and good health have become increasingly more important to the American public, yet there exists no compact, affordable, accurate device either for measurement or conditioning human strength or performance. This deficit hinders America’s ability to explore the frontiers of space as well. Without appropriate means to measure physical force requirements under zero-g conditions and without appropriate equipment for training for these task-related activities as well as against the deleterious physiological effects of microgravitational deconditioning, America’s permanent manned presence in space will be severely restricted.
One of the ways the human body reacts to the reduced physiological and mechanical demands of microgravity is by deconditioning of the cardiovascular, musculoskeletal, and neuromuscular systems. This deconditioning produces a multitude of physical changes such as loss of muscle mass, decreases in body density and body calcium, decreased muscle performance in strength and endurance, orthostatic intolerance, and overall decreases in aerobic and anaerobic fitness . The biomedical reports from the Gemini, Apollo, and Skylab missions and the work of Thornton and Rummell  have revealed a severe problem of reduced muscle mass and strength loss of the lower extremities following prolonged periods in microgravity. Since mission operations normally require relatively greater load demands for the arms and upper body than for the lower extremities, these findings were considered reasonable and not unexpected. However, the use of a bicycle ergometer on Skylab 2 was unable to provide sufficient aerobic exercise to maintain leg strength at earth-based, or 1-g, levels since it could develop neither the type nor the level of forces necessary. Devices which provided isokinetic resistance were employed on Skylabs 3 and 4 which resulted in higher leg force results than those generated in Skylab 2, but were limited to an inadequate level .
A review of the effects of strength training on human skeletal muscle suggests that the benefits of appropriate training would favorably counteract the negative effects of weightlessness. In general, strength training that uses large muscle groups in high-resistance, low-repetition efforts increases the maximum work output of the muscle group stressed . Since resistance training does not change the capacity of the specific types of skeletal muscle fibers to develop different tensions, strength is generally seen to increase with the cross-sectional area of the fiber . This may suggest an important finding in the effort to reduce or prevent the loss of muscle strength associated with reduced-g exposures. It may be that resistance training with the resultant hypertrophy would be an effective countermeasure for strength loss.
Since the cause of space deconditioning is usually attributed to the absence of gravity, the development of countermeasures is essential to interrupt these adverse adaptational effects and to develop activities which will sustain normal, robust fitness, conditioning, and good health. While experiments on the Gemini, Apollo, and Skylab missions suggest that regular exercise was helpful in minimizing several aspects of spaceflight deconditioning [6,7,8] there is a lack of quantifiable measures of specificity and amount of physical exercise performed by crew members during flight. Quantification of optimal intensity, frequency, and duration of exercise during spaceflight is of utmost importance for manned missions, yet “no data exists that provides even the slightest clue as to what the forces and impact load of locomotion are in microgravity” .
Countermeasures are efforts to counteract the physiological problems caused by exposure to zero-g by interrupting the body’s adaptation process. Effective countermeasures will promote mission safety, maximize mission successes, and maintain optimum crew health . Specific recommendations required by space missions were identified by participants at “The Manned System – A Human Factors Symposium and Workshop” sponsored by the American Astronautical Society. The need for appropriate fitness and recreation facilities, methods, and long-duration micro-gravity effects on EVA performance were identified as important topics by such diverse areas as habitat engineers, operation managers, EVA researchers, and the members of the Biomechanics group. The need for appropriate performance protocols as well as the development of a flight qualified dynamometer was emphasized.
The proposed equipment is intended for use as an effective countermeasure tool as well as addressing several of the operational restrictions imposed by spaceflight. Utilization of a hydraulic mechanism will provide a means for adequately creating resistance thus overcoming the ineffectiveness of weight-based equipment in zero-g. The apparatus will be compact, portable, and powered by low-voltage DC batteries which eliminates the need for shuttle power. These attributes are deemed necessary for easy and safe use in the restricted confines of the shuttle or on the space station. Computerization will provide several important innovations: (1) Activities performed will be programmable for “individualized” diagnostic routines and/or exercise protocols with results stored for subsequent evaluations. (2) The feedback control afforded by rapid computerized assessment and adjustment will ensure that the equipment will adjust to the performance levels of the astronaut rather than the reverse. Individualized adjustment assures that size and/or gender are irrelevant for successful operation. (3) Activities can be designed bi-directionally since resistance will be provided in both directions of bar movement. (4) Graphic displays and audio cues will provide information to the individual with such items as current strength level, repetition number, and bar location. The sound cues will be modulated in proportion to the exerted force in order to inform the individual about his or her performance response without the need to see the computer monitor. This will simplify operation as well as providing biofeedback. One of the most important features of the proposed device will be its functionality under all gravitational fields. Thus, medical and physiological researchers can design and test models on earth with the ability to recreate and evaluate the same models under reduced-g conditions.
The proposed device is specifically envisioned for application in musculoskeletal activities such as strength and endurance. However, its use as a criterion measure in quantification and/or verification of task performances in research strategies concerning bone demineralization, leg compliance, muscle size, and leg volume, may be appropriate. For example, the NASA Exercise Countermeasure Project Task Force, chaired by William G. Squires, Ph.D., determined that the validity and effectiveness of exercise countermeasures will be determined from the results of inflight studies and that the elucidation of the basic mechanisms from space- and earth-based research would develop specific acute and chronic exercise regimens to counteract physiological dysfunctions. The proposed Computerized Portable Dynamometer would appear to be an appropriate measurement device for such research.
2. PHASE I TECHNICAL OBJECTIVES
The goal of Phase I is to develop an operational computerized, feedback-controlled, portable, battery-powered, hydraulic dynamometer for use in 1-g conditions. The specific objectives required to accomplish this task are as follows:
(1) Objective 1. To select a portable, battery-powered computer which has the capability of interfacing with a Controller board used for analog to digital signal processing and dynamometer control. Additional attention will focus on disk storage capacity, secondary storage mediums, such as floppy drives, and visual display characteristics.
(2) Objective 2. To develop software on the computer identified in Objective 1 to operate the dynamometer.
(3) Objective 3. To test both the developed software and the portable computer on an existing device that utilizes a hydraulic valve, pack, and cylinder unit with an attached bar. Force and position transducers will provide the analog input signals.
(4) Objective 4. To test the calibration of the proposed dynamometer device using known weights.
(5) Objective 5. To conduct a simple experimental test using a squat exercise (a standing knee extension/flexion motion) to demonstrate both the feasibility and the functional capacities of the proposed device.
The two major feasibility questions to be answered in Phase I are: (1) Is there a portable, battery-powered computer commercially available with sufficient speed, memory, and storage capabilities, and which has the capacity to interface with a customized analog-to-digital (Controller) board, to support the proposed dynamometer? (2) Can appropriate software be written for the proposed dynamometer to control, assess, and store data required for evaluation and testing the human muscular strength and endurance functions previously discussed? The software considerations are not trivial. For example, several problems to be overcome include (a) the power requirements of the computer, the Controller board, and the transducers must be satisfied more efficiently than with the greater capacities afforded with external power supplies of larger computers, (b) rapid computer processing requires innovative programming code to afford smooth response for real-time feedback control, and (3) the flat panel monochrome display characteristics associated with portable, built-in single monitor computers present a unique challenge concerning the speed and esthetic qualities for the interactive visual medium.
During Phase I, the proposed dynamometer will be developed for earth-fixed environments. All information generated and developed in Phase I will be utilized in Phase II expansions. In Phase II, the proposed dynamometer will be developed on a portable, battery-powered computer with the capability of connecting the Controller board through an expansion bus. A specialized Controller board will be designed to fit within the designated computer and will be enhanced to allow additional analog input devices such as electromyography (EMG) and/or force plate data. During Phase II, attention will be given to developing a variety of options for force measurements by simple and creative orientations of the hydraulic cylinder with the bar, or handle, or other human/machine interaction points. Particular emphasis will be placed on mechanical designs appropriate for tests conducted in the restricted dimensions of reduced-g and zero-g workspaces. More extensive software attributes will be developed during Phase II as well. The developed product will be directed for use on shuttle flights, for a future space station, for lunar or Mars colonization, and for use as a measurement tool in the NASA research testing programs, such as examining neuromuscular forces, muscular strength, conditioning and deconditioning, habitat facilities, EVA studies, and others. Subsequent commercial use seems particularly applicable in instances where physical space is limited.
3. PHASE I WORK PLAN
The most important goal of the Phase I efforts is the production of adequate software on an appropriate portable, battery-powered computer to demonstrate the operational capabilities of the proposed dynamometer project successfully and sufficiently. An acceptable portable computer will be attached to an existing hydraulic pack and cylinder unit with an attached bar. The position and force transducers will provide the input signals through the Controller board. A simple experimental study will be conducted to compare force results registered by the dynamometer with those simultaneously secured on a force plate. The following presentation more fully describes the details for each of the essential components.
The physical characteristics of the computer are of paramount importance in the microgravitional workspaces where the proposed dynamometer project is targeted for ultimate use. The dynamometer must be able to obtain force measurements, throughout a range of movement, as well as to provide a means of controlling the velocity or the resistance generated by the user. The performance criteria of the proposed dynamometer necessitate rapid computer processing speed, adequate memory, and rapid analog to digital conversions. The computer must be portable, as light-weight as possible, possess graphics display capability, and it must function on its own battery power which will eliminate any need for shuttle power. To insure sufficient speed, the computer must have an 80386SX or higher processor which has an Industry Standard Architecture (ISA) bus. It is anticipated that four (4) megabytes of memory will be sufficient for Phase I. Both a hard disk and at least one other storage medium, such as a floppy disk, are essential to ensure preservation of data, particularly that secured during zero-g missions. Compatibility with an external signal processing board is required. In Phase I only, the use of an expansion chassis to house this external board may be necessary but is not anticipated. A currently available customized Controller board will be used during the Phase I feasibility study. Any modification of this board for Phase I uses will be minor.
Because of the compactness of design and the ability to operate with a single monitor, either with or without a “Windows” environment, it is anticipated that one of the “laptop” computers will be selected for the proposed project. Because of the rapidly changing technologies in the commercially available computer hardware, selection of the specific computer to be used in Phase II will be postponed until that time. The computer selected for Phase II will be required to have provisions for an internal expansion slot for inclusion of a specially designed Controller board.
b. Controller Board.
The Controller board consists of specialized electronics which will perform analog-to-digital (A/D) conversions of the input signals received from both the position and the force transducers. Analog input signals are the standard characteristic of these sensory devices. The Controller board also has the appropriate electronics for controlling and powering the resistive mechanism of the dynamometer. Processing of the two analog input devices as well as transmission of the subsequent software generated digital signal to regulate the stepper motor attached to the hydraulic valve and cylinder unit must be rapid and precisely regulated for accurate and smooth performance results.
The Controller board utilized for the Phase I dynamometer will be an existing customized board and any modifications will be minor. However, a specialized board will be developed for the Phase II dynamometer product. The Controller board connects to the ISA bus of the computer, which powers both the controller board and the dynamometer. This is a very ambitious plan which requires that the Controller board be designed to require an absolute minimum of power so that the computer’s batteries are not overly taxed. A worse case scenario would require that an additional, separate battery supply be incorporated into the design in Phase II. However, the additional battery would not appreciably increase the weight nor necessiate shuttle power. Further enhancements under consideration for Phase II include providing additional optional channels for securing EMG, heart rate, EKG, blood pressure, and/or other analog signal data.
c. Dynamometer Frame Mechanism.
In Phase I, an existing frame will be utilized for testing the proposed computer and software developed. In Phase II, a dynamometer frame will be developed which is compact and light-weight with a target weight of less than 10 kilograms. This is an ambitious design goal which will require frame materials to have maximum strength-to-weight ratios and the structure must be engineered with attention directed towards compactness, storage size, and both ease and versatility of operation. An additional consideration during Phase II development is to have the entire system readily adaptable to flight specifications.
d. Force and Position Transducers.
Existing transducers available commercially will be utilized for the proposed Phase I dynamometer project. The function of these input devices is to supply information to the computer relative to the location of the bar or handle against which the individual is exerting force as well as the amount of that force. This information must be provided rapidly enough for the computer to process the input signal and respond with an adjustment, if needed, to the hydraulic valve assembly so that the internal response adjustments are undetectable by the individual using the device. A characteristic essential to the proposed dynamometer is that the individual exerting force perceives only smooth operation and is insulated from any detection of hardware and/or functional adjustments. The continual exchange of data between input sensors and the regulation of the hydraulic system is one of the most crucial segments of the software programs to be prepared during the Phase I portion of the product development.
e. Hydraulic Valve, Pack, and Cylinder Unit and Stepper Motor.
An existing hydraulic valve, pack, and cylinder assembly which is currently integrated with an existing, commercially available stepper motor will be modified for use in the Phase I project. A stepper motor is attached to a hydraulic valve assembly which opens and closes an orifice regulating the flow of hydraulic fluid, thus controlling the amount of force needed to push or pull the piston within the cylinder. Since the main thrust of Phase I is to develop sufficient software capabilities on a portable, battery-powered computer to demonstrate the ability to measure and store forces, the development of a specialized hydraulic device with its related valve controls will be postponed until Phase II.
During Phase II, the design of a smaller and lighter hydraulic valve, pack, and cylinder assembly is envisioned. A further consideration is to use a flight-qualified fluid which would be more appropriate for microgravitational locations, such as in the shuttle or space station. Consideration of alternative resistive mechanisms have been abandoned because of the limitations imposed in zero-g conditions. Weight-based devices would have no value under reduced-g or zero-g conditions. Pneumatic resistance was rejected because of the pressure requirements, the problems associated with compressibility of gases, the difficulties associated with accuracy and calibration of measurements, and the need for pressurized cylinders. Hydraulic mechanisms are less affected by gravitational forces, can be regulated by low voltage, battery powered devices, can operate in both up and down stroke directions, and can function passively. Consideration of an “active” hydraulic system, which would provide conditions in which the individual would have to resist forces generated by the dynamometer, were rejected for the following reasons: (1) user safety, (2) decision against employing any motorized devices within zero-g workspaces for environmental safety considerations, and (3) more than sufficient and adequate results are obtainable with “passive” mechanisms.
Since one of the primary objectives in Phase I of the proposed dynamometer project is both to assess force levels throughout a range of motion and to provide a mechanism for conditioning, the initial software efforts will concentrate on this task. The software for the proposed dynamometer project must be capable of performing a variety of measurements as well as controlling repetitive movements and storing the generated data. Control of the hardware must be rapid and accurate to ensure smoothness of response. There must be appropriate means to interact with the individual and to access the resulting data. The proposed software developments should be considered on two levels. One level of software will be invisible to the individual using the dynamometer device since it will control the various hardware components. The second level of software will allow user/computer interaction. The computer programs necessary to provide the real-time feedback control, the data program and storage, and the additional performance manipulations will be extensive. A large portion of the software for the proposed project currently exists but operates on a larger and faster computer system. Although the proposed project constrains the software to provide smooth, feedback-controlled operation with a smaller, less powerful computer, new or revised programming code will be completed by the appropriate personnel within the time frame allocated in Phase I.
The software which provides computer interaction with the individual operator should automatically present a menu of options when the dynamometer system is activated. The menu will include at least four options: (1) diagnostics, (2) controlled velocity, (3) controlled resistance, (4) controlled work. In all cases, motion will be regulated in both directions, that is, when the bar moves up and down. Each of these four options will be briefly described in the following sections. In Phase I, the exercise selected for use will be restricted to a standing vertical leg extension task and the descriptive sections are oriented from this frame of reference.
Selection of the diagnostics option will allow several parameters about that person to be evaluated and stored if desired. The diagnostic parameters will be the range of motion, the maximum force, and the maximum speed that the individual can move the bar for the specific Phase I test activity selected. The maximum force and maximum speed data will be determined at each discrete point in the range of movement as well as the average across the entire range. The diagnostic data could be used solely as isolated pre- and post-test measurements. However, the data can also be stored within the person’s profile so that subsequent actions and tests performed on the dynamometer can be customized to adjust to that specific individual’s characteristics.
The controlled velocity option will permit the individual to control the speed of bar movement. The pattern of the velocity will be determined by the person using the equipment and these choices of velocity patterns will include: (1) isokinetic, which will provide a constant speed throughout the range of motion; (2) variable speed, in which the speed at the beginning of the motion and the speed at the end of the stroke are different with the computer regulating a smooth transition between the two values; and (3) programmed speed, which will allow the user to specify a unique velocity pattern throughout the range of movement. For each of the choices, determination of the initial and final velocities will be at the discretion of the individual through an interactive menu. The number of repetitions to be performed will also be indicated by the person. It will be possible to designate different patterns of velocity for each direction of bar movement.
The controlled resistance option will enable the person to control the resistance or amount of force required to move the bar. The alternatives will include: (1) isotonic, which will provide a constant amount of force for the individual to overcome in order to move the bar; (2) variable resistance, in which the force at the beginning of the motion and the force at the end of the movement are different with the computer regulating a smooth transition between the two values; (3) programmed resistance, which will permit the individual to specify a unique force pattern throughout the range of movement. An interactive menu will enable the person to indicate the precise initial and final values, the number of repetitions to be used, and each direction of bar motion will be independently programmed for each of the three choices.
The controlled work option will allow the individual to determine the amount of work, in Newton/meters or joules, to be performed rather than the number of repetitions. In addition, the person will be able to choose either velocity or resistance as the method for controlling the bar movement. As with the previous options, bi-directional control will be possible.
The data storage capability will be useful in the design of research protocols. The software will be designed to allow an investigator to “program” a specific series of exercises and the precise manner in which they are to be performed, e.g. number of repetitions, amount of work, etc., so that the astronaut need only select his or her name from the graphic menu and the computer will then guide the procedures. Data gathered can be stored for subsequent analysis. The proposed dynamometer will have the capacity to “program” a sequence of events, such as a series of different exercises; determination of that sequence will be solely at the discretion of the research investigator or other user. Data storage will be presented as an option; it will not be a required mode of operation. The proposed dynamometer will be fully operational for all options irrespective of whether the data storage option is activated.
In Phase I, control of the dynamometer will be through graphic menu displays and keyboard input by the individual for option selection and determination of information, such as velocity, resistance, work, and other necessary values. While the person pushes up and pulls down on the bar, both graphic and audio cues will be provided to indicate the current amount of force generated, the repetition number, and the location of the bar. In Phase II, computer/human interface via a mouse, trackball, or any acceptable pointing device rather than through the keyboard, more extensive graphics, and additional options are anticipated.
More extensive software enhancements will be developed in Phase II. For example, the ability to challenge the individual by placing a target on the graphic display. The person will then try to “hit” the target through greater effort. A “Fatigue” mode will be developed. This will allow the person to specify a decrement level so that when the performance deteriorates to that level, the computer will terminate the exercise. This may be a particularly important feature for use on rigorous missions. For those crew members involved in exhaustive work, such as extended EVA activities, computer intervention at a prescribed fatigue level may prevent undesirable overexertion yet allow sufficient exercise performance.
Accuracy of measurement is essential and it is deemed as one of the most important considerations in the software development. Calibration of the proposed dynamometer will be possible under dynamic conditions and is a unique feature that the computerization and the feedback system will allow. Calibration will be performed using weights with known values. The actual calibration procedure will allow the individual to place known weights at the starting position and, when released, force data will be sampled until the ending position is reached. The calibration procedure will be performed in both up and down directions. This type of calibration is unique in that the accuracy of the device can be ascertained throughout the range of motion. Restrictions of size and locations in the shuttle and space stations as well as the difficulties associated with weightlessness will necessitate an additional type of calibration for consideration in Phase II.
h. The Experimental Study.
An experimental study will be conducted to determine the functionality of the proposed device. As the Phase I goals are to select a portable, battery-powered computer and develop appropriate software on it, the study will be restricted to determining whether the Subjects can perform each of the four options previously described for one specific activity. The activity will be a squat exercise which is a standing knee extension/flexion motion.
i. The apparatus.
The equipment will consist of the computer and its operational software to be attached to an existing device suitable for performance of the squat exercise. The existing device has a hydraulic valve and cylinder attached to a bar which is both long enough and devised in a manner to accommodate this activity. The analog sensors and the digital control of the hydraulic stepper motor will be electronically interfaced with the computer through the previously discussed Controller board.
ii. The population.
Eight normal male subjects will be selected. The subjects will range in age from 25 to 45 and be of average height and weight. Subjects will be healthy and free of any physical disability.
iii. The protocol.
Each Subject will be tested on one day for approximately one hour with a ten minute break between each of the four menu options. A brief familiarization process will precede the test. A test will consist of performing the squat exercise for each of the four options; that is, diagnostics, controlled velocity, controlled resistance, and controlled work. All tests will begin with the diagnostic option. The order of the remaining three options will be varied to reduce any effects of learning but the Subjects will be randomly assigned to each of the specific procedures.
The diagnostic option will consist of one trial of each of the following (1) maximum range of motion, (2) maximum velocity, and (3) maximum force for each Subject. The controlled velocity option will use an isokinetic type of exercise beginning at 20 degrees per second and ending at 35 degrees per second. This speed and type will be used only in the up directions. For the down direction, the speed will be set at 100 degrees per second for the entire range. The controlled resistance option will be an isotonic type of exercise. Using the diagnostic results, the assigned resistance will be 75% of each person’s maximum throughout the entire exercise movement in the upward direction. The resistance setting for the down direction will be set at 10 percent of the individual’s maximum as determined in the diagnostic phase. The controlled work option will specify the amount of work as 7500 Newton/meters and will use the controlled velocity mode as the type of exercise.
i. Evaluation and Results.
The ability to perform the specified tests by the Subjects while interacting with the proposed computer and its software will determine the success or failure of the proposed project. A questionaire will be completed by each Subject concerning the tasks, the success of operation, and other pertinent information. Data gleaned from the questionaire will be valuable in determining the operational success of the proposed project.
j. Work Site.
All of the developmental and test work previously described will be conducted at Computerized Biomechanical Analysis, Inc., the applicant site. This includes the software development on the selected computer and the experimental study. All necessary equipment is currently available on site.
k. Timetable and Personnel.
Dr. Gideon B. Ariel, the principal investigator; Dr. M. Ann Penny, an exercise scientist with expertise in neuromuscular integration; Dr. Jeremy Wise, a software engineer; a TBA programmer; Mr. John D. Probe, a mechanical engineer; Dr. Ruth A. Maulucci, an information scientist with expertise in human performance and rehabilitation; and Dr. Richard Eckhouse, Jr., an electrical and computer engineer are the personnel who will perform the work. The specific tasks to be accomplished, the key person responsible, and the time for completion are outlined below:
Task 1. Choose the computer; Ariel, Wise, and Eckhouse; month 1.
Task 2. Software development; Wise, TBA, supervised by Wise, and
Eckhouse; months 1, 2, and 3.
Task 3. Arrange experimental apparatus; Penny, Probe, and Maulucci;
Task 4. Recruit subjects; Penny; month 3.
Task 5. Modify and/or debug software; Wise and Ariel; month 4.
Task 6. Perform experimental study; Penny, Probe, and Maulucci;
Task 7. Prepare final report; Ariel and Penny; month 6.
4. RELATED RESEARCH OR R&D
a. Recent Developments by Others.
The ability to assess strength and/or to exercise has occupied centuries of thought and effort. Since Milo the Greek lifted a calf each day until the baby grew into a bull, humans have attempted to provide suitable means to determine strength levels and ways to develop and maintain conditioning. However, most exercise equipment is gravity dependent and, therefore, would be ineffective in a weightless environment. Space flight exercise devices have been similar in design and function with many earth-bound devices but have been adapted for reduced-g applications. These devices include treadmills, bicycle ergometers, rowing machines, and other equipment. For purposes of this proposal, attention will be restricted to equipment utilized or proposed for use on shuttle missions and those most recent developments commercially available.
Treadmills have been used on all Russian Salyut space stations, Skylab 4, and Shuttle orbitors . The treadmill currently used as standard exercise equipment on shuttle missions was designed in 1974 . The rolling tread is coupled to a flywheel, brake, and tachometer using pulleys and belts. Speed may be varied at different levels by a rapid onset centrifugal brake. The astronaut provides earth equivalent body weight loading by adjusting a harness and rubber bungee cord arrangement. The treadmill is a passive device so that movement is produced by the astronaut leaning forward and pushing with the legs in a manner similar to running uphill on Earth. The treadmill models used on Skylabs 3 and 4 provided leg forces higher than those produced on a bicycle ergometer, but were below an adequate level demanded for return to 1-g . There are no provisions for regulation nor recording of strength performance data with any of the treadmill units.
Bicycle ergometers have been utilized on shuttle, Skylab, and Russian spacecraft. The U.S. models employ a seat for support in 1-g environments with the head and arms providing counterforces in zero-g settings . On Skylab, the bicycle ergometer was used to provide a quantitative stress level for studies of physiological response as well as the primary off-duty crew exercise apparatus [10,11]. Results from Skylab 2 indicated that while aerobic exercise and cardiorespiratory conditioning could be met through bicycle ergometer in-flight use, sufficient leg strength could not be maintained for 1-g needs . Although the bicycle ergometer models previously used could be controlled by the astronaut’s heart rate, manually, or by computer, strength and/or exercise data were not regulated nor was such data preserved.
Other types of exercise devices for space flight use have been considered. A flight qualified rowing machine is awaiting flight opportunity. This equipment provides foot restraints, since seats are unnecessary in weightlessness, and a cable with handles replaces the oars. Six discrete loads are provided. An internal NASA study found that the rower provided moderately heavy arm and back, but relatively small leg force loads . A “body weight load for isotonic exercise” device employs spring tension to replace the force of the human body in 1-g environments . Using a harness and pulleys, various isotonic exercises such as dips, squats, and chin ups can be performed on this apparatus. Another flight certified device is an isometric dynamometer . The dynamometer utilizes a stain gauge torque element to measure maximal bidirectional isometric shoulder, elbow, knee and hip strength. A stationary locomotion apparatus makes use of a body harness and elastic bungee cords allowing walking, jogging, or jumping in place under a constant load . None of the equipment mentioned above provides either for the regulation of exercise protocols nor the ability to record those parameters.
A plethora of exercise devices exist for earth-bound use ranging from simple cables, pulleys, and springs through more complex apparatus employing motors, air, hydraulics, etc. For example, various Cybex models provide hydraulic resistance and enjoy widespread use particularly in rehabilitation. However, the equipment provides non-varying isokinetic motion, cannot be calibrated dynamically, uses A/C power, requires high current, and is large. A Cybex model has been used on NASA’s KC-135 aircraft and in the Weightless Environmental Training Facility (WETF) but would seem to be inappropriate for microgravitational sites for many of the reasons mentioned. The Ariel Computerized Exercise equipment provides feedback controlled variable speed functions, but requires A/C power and is too large for spacecraft applications.
In summary, all earth-based equipment are inappropriate for microgravitational use for one or more of the following reasons: (1) function only in normal gravitational environments, (2) use motors, need A/C power, require high current, and/or generate excessive heat, and (3) have excessive weight and/or are prohibitively large in size for use in the confined areas found on spacecraft or Space Stations.
b. Significant Research Conducted by the Principal Investigator.
Dr. Gideon B. Ariel, the principal investigator for this proposed device, has designed equipment for testing and exercising humans, has developed computerized software products, and has designed, developed, and manufactured computerized exercise equipment. The unique amalgamation of academic and professional expertise in human performance, mechanics, and computers are evident in the research and products developed by Dr. Ariel. The hallmarks of his research and the products he has developed are accuracy, quantification, and practicality.
Dr. Ariel had extensive experience in physical fitness and conditioning as an athlete, while participating in two Olympic Games, and in his early academic preparation. In the early 1970s, Dr. Ariel conducted studies assessing human performance criteria and, in addition, produced the first studies on anabolic steroids using trained athletes as Subjects . His findings revealed that statistically significant strength gains resulted from ingestion of an anabolic steroid, and these increases were not merely a placebo effect. Other publications presented results on exercise, training, and athletic performances.
While studying biomechanics in graduate school, Dr. Ariel recognized the lack of and the need for a system to quantify human motion. After receiving his doctoral degree, he combined his biomechanical training with his knowledge of computer programming guiding his small staff in the development of a computerized analysis system. This biomechanical analysis system was based upon Newtonian equations and produced the three-dimensional coordinates of the joints centers of a body. The computerized hardware/software system provided a means to objectively quantify the dynamic components of athletic events replacing mere observation and supposition. For approximately ten years, Dr. Ariel worked with numerous corporations, primarily in product assessment and their subsequent modifications. In addition, he worked closely with the United States Olympic Committee in the quantification of various athletic events and established the biomechanics laboratory at the U.S. Olympic Training facility in Colorado Springs, Colorado. Based upon this foundation of business experiences, programming skills, and awareness of the computer industry’s rapid evolution from large main frames to mini and micro computers, Dr. Ariel has guided the development of his computerized motion analysis system into a product available commercially.
The invention of an computerized exercise machine was a natural evolution of Dr. Ariel’s personal and academic investigations into physical conditioning, motion analysis, computers, and electronic as well as his knowledge of available, non-computerized exercise equipment. Currently three of Dr. Ariel’s patented computerized exercise devices are marketed commercially.
c. Bibliographic References In Support of the Proposal.
 Squires, W.G., Tate, C.A., Raven, P.B., Vailas, A.C., Morgan, W.P. and Bishop, P.A. “Final report – exercise countermeasures project.” Prepared by the Discipline Implementation Team, Johnson Space Center, Submitted October, 1990.
 Thornton, W. and Rummel, J. “Muscular deconditioning and its prevention in space flight.” In: Biomedical Results from Skylab, Chapter 21. Ed. R. Johnston and R. Dietlein. Washington, D.C. NASA, 1977.
 Greenisen, Michael C. “Mechanics, impact loads, and EMG analyses of locomotion on the shuttle treadmill.” NASA DSO Program document. Submitted, Feb. 2, 1990.
 Dudley, G. and Fleck, S. “Strength and endurance training: Are they mutually exclusive?” Sports Medicine, Vol. 4: pp. 79-85, 1987.
 McDonaugh, M. and Davies, C. “Adaptive response of mammalian skeletal muscle to exercise with high loads.” European Journal of Applied Physiology, Vol. 52: pp. 139-155, 1984.
 Michel, E.L., Rummel, J.A., Sawin, C.F., Buderer, M.C., and Lem, J.D. “Results of Skylab medical experiment M171: Metabolic activity.” In: Biomedical Results from Skylab. Chapter 36. Ed. R. Johnston and R. Dietlein. Washington, D.C. NASA, 1977.
 Walker, J., Greenisen, M., Cowell, L.L., and Squires, W.G. “Astronaut adaption to 1 G following long duration space flight.” Presentation at the 21st International Conference on Environmental Systems sponsored by the Engineering Society for Advancing Mobility Land Sea Air and Space, San Francisco, CA, July, 1991.
 Rummel, J.A., Michel, E.L., Sawin, C.F., and Buderer, M.C. “Metabolic studies during exercise: the second manned mission.” Aviation, Space, and Environmental Medicine, Vol. 47: pp. 1056-1060, 1976.
 Thornton, W. “Status review of flight exercise hardware, Johnson Space Center 1990”. NASA document. October 15, 1990.
 Johnson, R.S. “Skylab medical program overview.” In: Biomedical Results from Skylab. Chapter 1. Ed. R. Johnston and R. Dietlein. Washington, D.C. NASA, 1977.
 Moore, T.P. “The history of in-flight exercise in the U.S. Manned Space Program.” Proceedings of NASA sponsored Workshop on Exercise Prescription for Long-Duration Space Flight, Houston, Texas, 1989.
5. RELATIONSHIP WITH PHASE II OR OTHER FUTURE R/R&D
The ultimate result envisioned from the proposed project is a computerized, feedback-controlled, portable, battery-powered, hydraulic dynamometer which can be used in earth- and microgravitational environments. Phase I addresses only one of the essential components, namely the feasibility of using a portable, battery-powered computer and implementing operational software for earth-fixed use. During Phase II, attention will be extended to several areas including: (1) developing a specialized Controller board which will fit within the designated computer and will be enhanced to allow additional analog input devices; (2) designing a frame which will be light-weight and compact. Special attention will focus on versatility in order to maximize the number and variety of exercises; (3) selection of a portable computer with provisions for an internal expansion slot for inclusion of the Controller board; (4) design of a smaller and lighter hydraulic valve, pack, and cylinder assembly with consideration for use of flight qualified materials; (5) extensive software development will include more extensive graphics, data storage and evaluation features, different exercise options, such as a “performance target” and “fatigue” modes, and optional computer/operator interface devices, such as a mouse, trackball, or other pointing device; and, (6) consideration of calibration procedures in zero-g conditions.
6. POTENTIAL COMMERCIAL APPLICATIONS
The proposed equipment has commercial potential for use in any restricted-space area, such as submarines, homes, offices, and many medical and rehabilitative facilities. Another important feature of commercial value is the portability of the device which could expand the service opportunities for therapists in the areas of physical and occupational rehabilitation. The ability to transport a compact, portable exercise device to a patient’s location within a hospital or convalescent facility would enhance on-site therapeutic procedures. This could be particularly important for those individuals whose immobility would prohibit receipt of such services.
Commercialization of products emerging from research conducted at Computerized Biomechanical Analysis, Inc. is of interest to the company. Currently, the corporation derives royalties from previous research efforts and will aggressively pursue the marketing of the device proposed for this grant. Spin-off products based on the proposed equipment may be appropriate for children as well as for the elderly. During Phase I, contacts will be initiated to determine interest in Phase III commercialization of the proposed Computerized Portable Dynamometer.
7. COMPANY INFORMATION
Computerized Biomechanical Analysis, Inc. was established in 1971 to quantify human (the “Bio”) movement using the Newtonian equations of motion (the “mechanical”). Many of the early research investigations involved product assessment and design improvements for sporting goods companies, including golf balls and clubs, tennis rackets and balls, skis and ski boots, basketballs, softballs, as well as the shoes and apparel of various sports. Primary consideration was given to task analysis and performance expectations developed from quantification of empirically secured activity data. Subsequent product developments, improvements, and/or modifications were derived from actual human performance characteristics rather than estimated needs or current fads. Additional biomechanical studies include studies of violin performances, ballet, feminine hygiene products, feline and equine locomotion, hand writing, and numerous forensic investigations posed both by defense and prosecution. In addition, a major software project was sponsored by IBM.
The company and its staff have demonstrated their expertise in devising and conducting research inquires under vendor contract dictates as well as in independent, in-house initiatives. Project management begins with problem identification, proceeds through experimental formulation, data collection and reductions, interpretation of results, and formulation of prototypes, where needed, or of product alteration recommendations. The researchers at Computerized Biomechanical Analysis, Inc. possess the academic credentials and creative imaginations as illustrated in their individual and collective abilities at performing innovative tasks. In addition, understanding and enhancing human performance is a special interest of the company and each of its employees.
Extensive computer and peripheral hardware are available to the research scientists at Computerized Biomechanical Analysis, Inc. Computer systems currently in use include IBM models XT’s and AT’s, AST models 286, 386, and 486, Toshiba models T1600/40, T5100, and 1000SE. Monochrome and color, both EGA and VGA, monitors are utilized for different applications. Color, near-letter quality, and laser printers are available. A variety of languages are available to program developers so that each project can be executed in the most efficient and appropriate language for the specific need. Commercial application software programs including word processors, spreadsheets, data base managers, CAD/CAM, AutoCad, and graphic designs are frequently used for data reductions, for enhanced report presentations, and specialized board and product design and layout.
Ancillary hardware includes Kistler, AMTI, and Bertec force platforms, preamped electrodes for EMG data acquisition, and video cameras for motion analysis. Special customized software was developed at Computerized Biomechanical Analysis, Inc. for data collection, storage, and processing.
8. KEY COMPANY PERSONNEL
GIDEON B. ARIEL, Ph.D.
Ph.D. Exercise Science University of Massachusetts 1969-72
M.S. Exercise Science University of Massachusetts 1966-68
B.S. Physical Education University of Wyoming 1963-66
D.P.E. Physical Education Wingate College (Israel) 1958-60
United States Olympic Committee; Chairman and founder of Biomechanics Committee for Sports Medicine, 1976-84
Adjunct Professor – Hahnemann Univ., 1977-present
Adjunct Professor – University of California-Irvine, Department of Neurology, 1979-present
Adjunct Professor – University of Massachusetts, 1974-76
Assistant Professor – University of Massachusetts, 1972-75
Post Doctorate Research Associate-University of Massachusetts, 1974-76
Instructor – University of Massachusetts, 1968-70
Research and Teaching Assistant – University of Massachusetts, 1967-72
Computerized Biomechanical Analysis, Inc. – Founder and Vice President, 1971-present. A corporation dedicated to innovative research and product development.
Ariel Dynamics, Inc. – Founder and President, 1981-present. A corporation to manufacture and market exercise equipment. Minimal activity currently due to licensing agreement with Ariel Life Systems, Inc.
Ariel Performance Analysis, Inc. – Founder and President, 1986-present. A corporation to manufacture and market motion analysis equipment. Minimal activity currently due to licensing agreement with Ariel Life Systems, Inc.
Ariel Life System, Inc. – Founder and President, 1990-present. A corporation to manufacture and market exercise equipment and motion analysis system.
1. Variable resistance exercising device. No. 665,459, March 17, 1981.
2. Programmable variable resistance exercise. No. 4,354,676, October 19, 1982.
3. Passive programmable resistance device. No. 4,544,154, October 1, 1985.
Ariel, G.B. “The effect of knee joint angle on Harvard Step Test performance.” Ergonomics, Vol. 12: pp. 33-37, 1969.
Ariel, G.B. “Effect of anabolic steroids on reflex components.” Journal of Applied Physiology, Vol. 32: pp. 795-797, 1972.
Ariel, G.B. and Saville, W. “Anabolic steroids: physiological effects of placebos.” Medicine and Science in Sports, Vol. 4: pp. 124-126, 1972.
Ariel, G.B. “The effect of anabolic steroid upon skeletal muscle contractile force.” Journal of Sports Medicine and Physical Fitness, Vol. 13: pp. 187-190, 1973.
Ariel, G.B. “Computerized biomechanical analysis of human performance.” In: Mechanics and Sport, The American Society of Mechanical Engineers, Vol. 4: pp. 267-275, 1973.
Ariel, G.B. “Computerized biomechanical analysis of the knee joint during deep knee bend with heavy load.” In Biomechanics IV. Edited by R.C. Nelson and C.A. Morehouse, Fourth International Seminar on Biomechanics, Pennsylvania State University, 1973.
Ariel, G.B. “Prolonged effects of anabolic steroid upon muscular contractile force.” Medicine and Science in Sports, Vol. 6: pp.62-64, 1974.
Ariel, G.B. “Shear and compression forces in the knee joint during deep knee bend.” In: XXth World Congress in Sports Medicine Handbook, Melbourne, Australia, 1974.
Ariel, G.B. “Method for biomechanical analysis of human performance.” Research Quarterly, Vol. 45: pp. 72-79, 1974.
Ariel, G.B. “Computerized biomechanical analysis of athletic shoe.” Vth International Congress of Biomechanics Abstracts, Jyvaskyla, Finland, pp. 5, 1975.
Ariel, G.B. “Computerized biomechanical analysis of human performance.” In: Biomechanics of Sport. Ed. Thomas P. Martin, State University of New York at Brockport, pp. 228-229, 1975.
Ariel, G.B. and Maulucci, R.A. “Neural control of locomotion – a kinetic analysis of the trot in cats.” In: Neural Control of Locomotion. Ed. R.M. Herman, et.al., Plenum Publishing Corp., pp. 759-762, 1976.
Ariel, G.B. “Elementary biomechanics.” In: Therapeutics Through Exercise. Ed. D.L. Lowenthal, et.al., Grune and Stratton, pp. 99-102, 1979.
Ariel, G.B. “Human movement analysis.” Applied Ergonomics, Vol. 11: pp. 61-62, 1980.
Ariel, G.B. “Resistive Training.” Clinics in Sports Medicine, Vol. 2 (1): pp. 55-69, 1983.
Ariel, G.B. “Biofeedback and biomechanics in athletic training.” In: Biofeedback and Sports Science. Ed. J.H. Sandweiss and S.L. Wolf, Plenum Publishing Corp., pp. 107-145, 1985.
Ariel, G.B. “Body Mechanics.” In: Injuries to the Throwing Arm. Ed. B. Zarins, J.R. Andrews, and W.G. Carson, W.B. Saunders, Co., pp. 3-21, 1985.
Ariel, G.B. “Biomechanics of exercise fitness.” In: Encyclopedia of Medical Devices and Instrumentation. Ed. J.G. Webster, John Wiley & Sons, pp. 387-392, 1988.
Ariel, G.B. “Biomechanics.” In: Scientific Foundations of Sports Medicine. Ed. Carol C. Teitz, B.C. Decker, Inc. Chapter 12, pp. 271-297, 1989.
Dr. Gideon B. Ariel, the principal investigator for the proposed project, is the Vice President and founder of Computerized Biomechanical Analysis, Inc. Dr. Ariel is employed full time at Computerized Biomechanical Analysis, Inc. and will continue in this capacity during the Phase I and Phase II periods encompassed by the proposed project. Currently, he has allocated no time commitments for other projects in which he would function as the principal investigator during the Phase I and II portions of the proposed project.
M. Ann Penny, Ph.D.
Ph.D. Exercise Science University of Massachusetts 1973-77
M.S. Exercise Science University of Massachusetts 1968-73
B.S. Health and Phys- University of North Carolina 1962-66
President-Computerized Biomechanical Analysis, Inc. 1974-present
Vice President and Treasurer-Ariel Dynamics, Inc. 1981-present
Vice President and Treasurer-Ariel Performance
Analysis System, Inc. 1986-present
Confidential and/or proprietary research was the primary corporate involvement and, thus publications based on studies conducted by Dr. Penny were severely restricted. In the role of primary or co-investigator, the following representative sample of research investigations conducted by Dr. Penny includes: (1) feminine hygiene products, (2) feline and equine locomotion, (3) specialized forensic projects related to product liability, (4) quantification of numerous Olympic athletic events, and (5) extensive product evaluation and subsequent design specification. Her participation and involvement began at project inception, continued through data collection, and culminated with the preparation of the final report. Her insight, academic preparation, and efforts were, and continue to be, invaluable and irreplaceable.
PUBLICATIONS AND PRESENTATIONS
Wolf, S. L., Ariel, G. B., Saar, D., Penny, M.A., and Railey, P.A. “The effects of muscle stimulation during resistive training on performance parameters.” American Journal of Sports Medicine, Vol. 14(1): pp. 18-23, 1986.
Ariel, G.B., Saar, D., and Penny, M.A. “A computerized formation analysis of the women volleyball world cup championship in Japan, 1981.” presented at American College of Sports Medicine conference, Montreal, Canada, May, 1983.
Saar, D., Ariel, G.B., Penny, M.A., and Saar, I. “Aerobic adaptation to work and fatigue training modes on the computerized exercise system.” In: New Horizons of Human Movement, Vol. 3: pp. 171, Seoul Olympic Scientific Congress, Korea, 1988.
Ariel, G.B., Penny, M.A., Saar, D., and Railey, P.A. “Cardiovascular and muscular adaptation to training utilizing a computerized feedback-controlled modality.” In: New Horizons of Human Movement, Vol. 3: pp. 167, Seoul Olympic Scientific Congress, Korea, 1988.
Ariel, G.B., Penny, M.A., Saar, D., and Selinger, A. “Computer-controlled strength training program for the U.S. national women’s volleyball team.” In: New Horizons of Human Movement, Vol. 3: pp. 171, Seoul Olympic Scientific Congress, Korea, 1988.
Ariel, G.B., Saar, D., Wolf, S., Penny, M.A., and Railey, P.A. “The effects of muscle stimulation during dynamic resistive training on performance parameters.” In: New Horizons of Human Movement, Vol. 3: pp. 162, Seoul Olympic Scientific Congress, Korea, 1988.
JEREMY WISE, Ph.D.
Ph.D. Physics University of Massachusetts 1972-78
B.S. Physics Cornell University 1964-69
Jensen, D. Kreisler, M., Lomanno, F., Poster, R., Rabin, M., Smart, P. Wise, J, and Dakin, J. “A Computer Controlled Pulser System.” Nuclear Instruments and Methods, 1980.
Wise, J., Jensen, D., Kreisler, M., Lomanno, F., Poster, R., Rabin, M., Way, M., and Humphrey, J. “A High Statistics Study of Lambda Beta-Decay.” Bulletin of the American Physical Society, Vol. 23, No. 4: pp. 546, 1978.
Lomanno, F., Jensen, D., Kreisler, M., Poster, R., Rabin, M., Way, M., Wise, J., and Humphrey, J. “Measurement of Polarization in Inclusive Lambda Production at 28.5 Gev/c.” Bulletin of the American Physical Society, Vol. 23, No. 4: pp. 600, 1978.
Wise, Jeremy “Holography on a Low Budget.” American Journal of Physics, Vol 40: pp. 1866, 1972.
Dr. Wise has worked for Computerized Biomechanical Analysis, Inc. since 1978 and is currently the Director of Software Development. In addition to his exceptional computer programming skills, Dr. Wise has academic knowledge and laboratory experience in physics, high energy physics, mathematics, and electronics. During his tenure with the applicant corporation, he has been significantly involved in the development of extensive proprietary software. His services and his direction of the TBA graduate student programmer for the proposed project are essential.
9. SUBCONTRACTS AND CONSULTANTS
MOCO, inc., a small business biomedical research firm in Massachusetts, will be a subcontractor to this proposal (see attached letter of agreement). The company was established for the purpose of conducting research in human performance using the principles of mathematics, control theory, and computer and information science. The scientists at MOCO have performed extensive and diverse investigations aimed at understanding normal human functioning and at identifying and explaining abnormal behavior. MOCO, inc. will contribute seven days of consulting to this project at $300.00 per day. Ruth A. Maulucci, Ph.D. and Richard H. Eckhouse, Jr., Ph.D., the two principal employees at MOCO, inc. will serve as the named consultants. No logistic problems are anticipated, since MOCO, inc. has other projects involving performance sites in Arizona requiring several visitations during the period covered by this proposal.
Ruth A. Maulucci holds both a Masters and a Ph.D. degree in Computer and Information Science as well as a Masters degree in Mathematics. Dr. Maulucci is an information scientist with expertise in human performance and rehabilitation who has worked and published in the areas of biological signal processing, feedback and adaptation in the central nervous system, biomechanics and applications of optimal control theory, and mathematical modeling of biosystems. Her role in this project will be to advise on the design of the experimental paradigm and on the methods of feedback training. Her specific qualifications for this role are as follows. She has developed and is marketing a computerized workstation consisting of integrated feedback training programs for upper extremity control and balance. This workstation was developed under a Phase I and II SBIR grant from the Department of Health and Human Services. She has conducted a longitudinal experiment to study the maturational kinematic characteristics of upper extremity movement. In another study, she investigated the relationships between biomechanical and EMG parameters in normal adult males. Currently Dr. Maulucci is conducting an empirical study of reaching and locomotion under a Phase II NASA SBIR grant to determine the characteristics of the upper and lower extremities pertinent to the design of optimal workspaces for astronauts.
Richard H. Eckhouse, Jr. holds a Ph.D. degree in Computer Science and a Masters in Electrical Engineering. With more than 25 years of experience, Dr. Eckhouse is a nationally recognized authority, particularly in the areas of computer architecture, operating systems, and physiological instrumentation. He has worked in academia and industry, and is on the editorial board of several professional journals. He has published more than 30 articles in refereed journals as well as written several graduate textbooks which are used internationally. Dr. Eckhouse will assist in the hardware and software design decisions of this project.
John D. Probe holds a Masters degree in Engineering in Bioengineering and will serve as a consultant for the experimental portion of the proposed project. Until recently, Mr. Probe was employed by Lockheed Engineering and Sciences Company where he was assigned as an Engineer in the Anthropometry and Biomechanics Laboratory at the NASA Johnson Space Center in Houston, Texas. His work at NASA included data collection and analysis for validating NASA’s KC-135 research aircraft for “hyper-gravity” flights utilizing aircraft accelerometers and a portable data acquisition system; designed, implemented, and supervised testing in the Weightless Environment Training Facility (WETF) to determine IVA foot restraint reaction forces for a specified upper extremity workload; and served as the lead engineer for structural modifications of the Underwater Dynamometry System to prevent loosening of the dynamometer inside the waterproofed enclosure following extended use. Mr. Probe will work with Drs. Penny and Maulucci in preparing the experimental apparatus for the proposed project as well as assisting Dr. Penny in the experimental data collection. He will expend ten days effort on the project at $300.00 per day. No logistic problems are anticipated, since Mr. Probe spends approximately one day a week at the applicant site. Mr. Probe’s employer, Ariel Life Systems, Inc., has agreed to his participation in the project (see attached letter). There is a close business relationship between the two corporations since Ariel Life Systems currently manufactures and markets a product for which Computerized Biomechanical Analysis holds the patent and, it is anticipated that this company would be receptive to pursuing the proposed device during Phase III.