Vehicle Controller

Lunar Rover

technology

enables

quadriplegics

to drive cars

In 1972, a paraplegic named Tom Wertz saw Apollo astronauts driving the Lunar Rover with just one handusing a T-bar. After test-driving a rover himself he realized that if such technology could be adapted to automobiles, it would help handicapped people become more independent. NASA and the Department of Veterans Affairs agreed, and contracted with Johnson Engineering, Boulder, Colorado to implement Wertz' idea. Roughly ten years after Wertz witnessed Apollo's lunar exploration, Johnson installed a

prototype UnistikTM vehicle control in a Ford van.

Johnson designed a two-axis joystick that controls the vehicle's steering wheel, brake, and accelerator pedal. It allows the driver to control the vehicle through small, low-force hand motions, from any position.

The Unistik Controller was designed for C-5 quadriplegics, such as Wertz, who have spinal cord lesions at the fifth cervical vertebra. People with such severe injuries have very limited use of their upper extremities; they are able to move their hand only a few inches to either side. The joystick is ideal because it has a very low control resistance.

Unistik driving is simple. Moving the stick forward accelerates the vehicle, to the rear slows it down, and

left or right turns the steering wheel in the proper direction. Moving the joystick to the two o'clock position. for example, will yield an accelerating turn to the right. Another joystick controls turn signals and headlights. A push of a button deactivates the Unistik, returning the van to normal operation. Thus, both handicapped and able-bodied people can use the same vehicle.

Unistik also provides a platform for the evaluation of intelligent vehicle systems. The computer that controls its driving functions can receive input through a human-operated joystick, or from radar, laser, radio, and other sensor technologies. Unistik thereby enables research that will help all of us drive more safely on tomorrow's highways.

Human Tissue Stimulator

Physics Laboratory of Johns Hopkins University, Howard County, Maryland, and with the sponsorship of NASA's Goddard Space Flight Center.

The HTS is based on Goddarddeveloped technology employed in NASA's Astronomy Satellite-3. It incorporates the same nickel cadmium battery, telemetry, and command systems used in the satellite, but reduced to microminiature proportions so that the implantable element is the size of a deck of cards (shown above, lower left-hand corner of photo). In contrast to earlier stimulating devices-which require cumbersome, externally-carried power packs or have very limited lifetimesthe HTS is totally implantable.

The HTS includes a tiny rechargeable battery, an antenna, and electronics to receive and process commands. It reports on its own condition via telemetry, a wireless process wherein instrument data is converted to electrical signals and sent to a receiver where the signals are

translated into usable information.

Once implanted, the HTS can send electrical pulses through wire leads to targeted nerve centers or to particular areas of the brain. A control console (shown above) allows a physician to monitor and program the HTS, for example to alter the character and strength of the electrical impulses to address particular conditions such as intractable pain. The implant's nickel cadmium battery can be recharged through the skin, eliminating the need for frequent surgical replacement.

The benefits of the HTS can be swift and remarkable. The first implant, in 1983, involved a female patient who had severe involuntary movement disorders associated with multiple schlerosis. Several hours after surgery, the stimulator was applied to a part of the thalamus, a small region of the brain. The patient's tremors vanished-even though moments

earlier she had been unable to guide a cup of coffee to her lips.

Another implant was used to treat a man who for several years had suffered excruciating pain in his left arm, caused by a wrist injury in a fall. Implanted under his left arm, the HTS was connected by wire leads to electrodes on the brachial plexus, a group of nerves that link the spinal cord with the injured arm. When the stimulator was activated, the patient reported immediate relief from the pain.

Although the initial implants were successful, extensive testing is required before the HTS can be made available for general use. Within the next few years, Pacesetter Systems expects to produce commercial programmable neural stimulators based on the HTS.

an electrical current to separate fluid components and prevent interference from other compounds in the solution.

In the mid-1960s, NASA's Ames Research Center sponsored development of an automated electrophoresis device for the weightless environment of space. Designed for use on a monkeycarrying spacecraft to provide information on blood behavior in zero gravity, it never reached flight status. In 1972, a modified system was planned for use in the Skylab space station to study possible changes in astronauts' blood during long-term weightlessness. Although it did not fly in space, it was used in simulated weightlessness studies at Ames. Because the project had produced considerable advanced technology,

Recognizing the MLM's commercial potential, McDonnell Douglas converted the technology into a timesaving system for medical analysis called the AutoMicrobic System (AMS).

Instead of the petri dish customarily used to prepare cultures, AMS employs test kits-disposable, plastic cards approximately the size of a playing card, with each card containing from 16 to 30 wells that each hold a different chemical substance. There are two types of cards: identification cards and susceptibility cards. A body fluid sample is injected into the identification card and organisms in the sample react with the chemicals in

the wells. Mounted in trays, the cards are placed in the AMS' incubator/ reader module. Scanning each well once an hour, the system "reads" the reactions taking place, compares them with information in the computer, and identifies the organism-or gives a negative report when no organism is present. This data is reported on a display screen and printout.

Once an organism is identified, the body sample goes into the susceptibility card-whose wells contain a number of different antibiotics. This card is similarly inserted into the system for computer examination, to determine which antibiotic is most effective against the organism. The entire process takes from four to 13 hours, compared with two to four days for culture preparations. AMS can handle up to 240 specimens at one time.

In addition to enabling microbiology laboratories to furnish guidelines for antimicrobial treatment within one day of specimen collection, the AMS also minimizes human error, reduces technician time, and increases lab output. Beyond its medical uses, the AMS can serve in food processing and other industry laboratories for such applications as detection and identification of organisms during incoming, inprocess, and finished goods

inspections; identification of biological indicators in sterilization processes; and in-plant environmental testing.

Spinoffs include a portable firefighting module, protective clothing for workers in hazardous environments, fire-retardant paints and foams, fireblocking coatings for outdoor structures, and flame-resistant fabrics. Perhaps the farthest-reaching is the breathing apparatus worn by firefighters throughout the U.S. for protection from smoke inhalation injury.

In 1971, in response to concerns expressed by many of the nation's fire chiefs, NASA began the first concerted effort to improve firefighter breathing systems, which had not changed appreciably since the 1940s. The traditional breathing system was heavy, cumbersome, and so physically taxing that it often induced extreme fatigue. Many firefighters decided not to use the equipment, electing to brave the smoke rather than risk collapse from heat and exhaustion. As a result, smoke inhalation injuries increased.