Latest research finds real-world applications

New device stops table saw kickback
“Imagine being hit by a two-by-four going 60 to 100 miles per hour,” says Steve Nackers. That’s how he and fellow UW–Madison undergraduate engineering student Brandon Ripley describe kickback, a common hazard of table-saw operation they hope to overcome with a new electro-mechanical safety device.

In kickback, a piece of wood binds in a table saw during cutting, catches on the blade, and is then shot from the saw at bone-braking speed. Nackers and Ripley’s device senses the telltale strain that develops as a board catches in the saw, and it shuts down the blade before the board can fly.

Originally designed for the 2002 Schoofs Prize for Creativity and the Tong Prototype Prize competitions – earning third place in both – the device is now being patented by the Wisconsin Alumni Research Foundation (WARF).

Most table saws are already outfitted with anti-kickback devices, say the students, both avid woodworkers. These gadgets usually consist of a guard mounted over the blade, with teeth to contain a board should it begin to take flight. But the guards can interfere with cutting operations and scratch the wood; in fact, they often create such a nuisance that people remove them, risking harm to themselves and others.

In designing their anti-kickback device, Nackers says, “We went with physics, rather than a containment approach.” To measure the physical forces involved, they placed strain gauges on a saw blade’s motor mount, and then sawed through everything from plywood and treated lumber, to two-by-fours and particleboard.

Kickback, they observed, produces a distinct fingerprint – a slight drop in strain followed by a pronounced spike. When their device detects this signature, it signals the motor to shut down, applies a brake to the blade, and brings the blade to a complete halt, all within one-tenth of a second. At the same time, they noted little evidence that the device caused unnecessary stops of the saw.

Given its capacity to ensure safety without interfering with normal cutting operations, the device should strongly appeal to table-saw users, the pair says. They’re also betting its high-tech approach will induce a fair amount of “table-saw envy.”

“People tend to like electronic gadgets in general,” says Nackers. “You’re more likely to go gawk at your neighbor’s new table saw if it has the latest anti-kickback system.” And, he hopes, buy one yourself.

Measuring the sickness factor of colds
Got a cold? A new questionnaire developed by UW–Madison doctors to evaluate the severity and functional impact of the common cold experience could help.

Even though hundreds of remedies have been developed to treat cold symptoms – stuffed-up noses, scratchy throats, nagging coughs – no well-developed survey instrument exists that measures the severity of all the problems affecting cold sufferers, says Bruce Barrett, a UW–Madison family medicine professor.

Barrett, who in 1998 was designing his own study to determine the effectiveness of the herbal remedy echinacea to treat colds, decided to develop his own. “I needed to look at outcomes affecting patients,” he says, “and I needed something to measure that.” What he required, he explains, was a “validated illness-specific quality-of-life instrument.”

So, he invited area cold sufferers to his office and asked them to list all their symptoms, describe the most bothersome ones, and explain how colds had affected their daily lives, including job performance, relationships and normal activities. To his surprise, he says, the study participants reported not just biological symptoms, but also problems coping with daily activities.

With the help of cold sufferers and research focus groups, Barrett and his colleagues developed a questionnaire called the “Wisconsin Upper Respiratory Symptom Survey.” The survey asks those with colds to rate the severity of 32 different physical and psychological symptoms, as well as the impact the illness has on 10 daily activities, such as sleeping, thinking clearly and interacting with others. In addition, cold sufferers describe how they feel today, compared to yesterday.

Answers to these questions, Barrett says, could enable cold sufferers to chart changes in symptoms; doctors to determine if patients might have something other than a cold; and medical researchers, like himself, to compare the effectiveness of alternative treatments.

Barrett continues to research and develop the survey, which is licensed by the Wisconsin Alumni Research Foundation. He is currently looking for research participants in the area who are coming down with colds. Those interested can call (608) 576-9276.

Toning the tongue
Consider the tongue: It may not be the biggest muscle in our body, but it plays a major role in our health. To keep the tongue in shape, biomedical engineering undergraduates at UW–Madison have invented a device that gives this muscle a workout and also helps physicians measure its strength. The results could help the 15 million adults who have health problems related to swallowing.

As people age, the strength of their mouth muscles, like any other muscle in the body, deteriorates. This atrophy can lead to swallowing problem, which then can lead to pneumonia, malnutrition, dehydration and even sleep apnea, says JoAnne Robbins, UW–Madison medical professor and associate director of the Geriatrics Research, Education and Clinical Center at the William S. Middleton Memorial VA Medical Center in Madison. (Robbins had originally suggested the students create a state-of-the-art device that’s both diagnostic and therapeutic.)

But exercise, as it does with other muscles, can rebuild tongue strength and muscle mass, says Robbins. Being able to measure this strength, she adds, is equally important for diagnostic purposes.

While such devices are already on the market, most rely on a small, air-filled bulb. This bulb, however, punctures easily and can slide around the mouth, making both exercise and taking accurate measurements difficult.

The students’ device, on the other hand, uses a custom-fit mouth guard that includes two sensors that detect levels of pressure when a wearer lifts his tongue to the roof of the mouth. This data is transmitted to a portable box, which provides digital and audio feedback. While the digital readout is mainly for medical staff, the audio cues can help patients recognize when they’ve reached a particular goal, says Angela Hewitt of Chetek, Wis., one of the student inventors. The students spent about $240 to develop the prototype.

Last November, the tongue-toning device was one of 16 projects to compete at the annual Collegiate Inventors Competition, sponsored by the National Inventors Hall of Fame. The UW–Madison project may not have placed, but the Wisconsin Alumni Research Foundation has filed a patent on it.