A provisional patent on the device, which has drawn interest from Concept2, a manufacturer of indoor rowers, was recently filed by the Capstone group. (Photo by Matthew Modoono/Northeastern University.) A provisional patent on the device, which has drawn interest from Concept2, a manufacturer of indoor rowers, was recently filed by the Capstone group. (Photo by Matthew Modoono/Northeastern University.)

A provisional patent on the device, which has drawn interest from Concept2, a manufacturer of indoor rowers, was recently filed by the Capstone group. (Photo by Matthew Modoono/Northeastern University.)

Physical therapists at Spaulding Rehabilitation Hospital, Boston, spurred student-researchers at Northeastern University to develop a modified ergometer that can be used by patients affected by spastic paraplegia to perform unaided exercise.

The device, dubbed the “power row,” was the subject of a senior cap­stone project under the direc­tion of Sandra She­fel­bine, an asso­ciate pro­fessor of mechan­ical and indus­trial engi­neering, according to a media release from Northeastern University. Team mem­bers com­prised Mar­garet Bergson, Robert Grif­fith, Jenna Hor­mann, Chris Parfitt, and Nikita Shah.

The project grew out of a problem-??solving meeting between the young engi­neers and the phys­ical ther­a­pists at the Spaulding Reha­bil­i­ta­tion Hos­pital in Boston. The problem, the phys­ical ther­a­pists told the stu­dents, was that some two dozen patients living with a med­ical con­di­tion known as spastic para­plegia lacked suf­fi­cient motor con­trol of their legs to return to the starting posi­tion after taking each stroke on their rowing erg. Trainers had to push patients for­ward using the handle bar on the back of the their seat, applying up to 130 pounds of force to over­come their inability to flex their legs. The solu­tion, both par­ties agreed, was to design a motor­ized device that would allow the patients to exer­cise in their own homes without a trainer’s assistance.

After designing three original concepts, the group of five students settled on a pro­to­type that uti­lizes a gear system to trans­late torque from a brush­less ser­vo­motor to a cap­stan, which moves the seat.

According to the media release, the students proposed that their final design offers two key advantages. First, the device remains under­neath the erg, which is said to allow the system to operate without inter­fering with the rower’s workout. Second, the ser­vo­motor allows for flex­i­bility in speed and torque, which can be changed based on the size and ability of the rower.

The students assert that Spaulding patents will soon begin using the retro­fitted rowing machine, and offer feed­back. Even­tu­ally, the students note in the media release, they will seek to modify additional ergs for the facility, and estimate the cost of the modification at approx­i­mately $100 per machine.

A pro­vi­sional patent for the device was recently filed by the five students, according to the university media release. The filing is said to have drawn interest from Concept2, a man­u­fac­turer of indoor rowers.

“A device like ours does not cur­rently exist in the market,” Shah says in the media release. Shah recently grad­u­ated with a bachelor of science degree in mechan­ical engi­neering, and says the device is in demand by both people with para­plegia and their trainers.

[Source: Northeastern University]