ORONO – University of Maine engineering students received more than just class credit for their senior projects this year – they received the satisfaction of helping others through their designs.

Projects included a wheelchair accessible pontoon boat, a computer workstation for the disabled, and a Stirling cycle engine affordably priced for classroom demonstrations.

“We always are doing something new,” said Herb Crosby, UM mechanical engineering professor. “What we prefer doing is something to help someone.”

The 29 mechanical engineering students have been working on their projects for the last two semesters and showed them off at the senior design exposition Wednesday.

Each team receives $200 from the university to put toward its project. For additional funding, “they had to rely on the good will of industry,” Crosby said.

The teams also have mentors who provide the students with outside knowledge, Crosby explained. Some of these mentors are even the inspiration behind the design. Doug Sewall, 56, of Orono was diagnosed with polio when he was 6 years old and has had limited use of his legs ever since.

Using the design of Sewall’s hand-powered bicycle as the basis for the watercraft, the six-member water bike team built a wheelchair accessible pontoon boat that is so stable it’s almost impossible to overturn. The boat’s portability and handling also were concerns, but Sewall’s input helped the team develop effective solutions.

“I rode it and I thought they did a great job,” Sewall said. “I was really impressed with how easy it pedals and how maneuverable it is.”

The team plans to donate the boat, which contains about $1,000 worth of materials, to Paul Stern. Stern teaches adaptive water sports classes to disabled persons and also acted as a mentor to the team.

“The workmanship as well as the thought that they put into this is impressive,” Sewall said.

The mentors volunteer their time, but it’s well worth it, according to Bill Lynch who assisted two teams who are working to restore a Lombard Log Hauler engine and drive train.

“This is a good experience for them because it prepares them for what they’re going to encounter in real life,” Bill Lynch said. Lynch is the chairman of the Maine Forest and Logging Museum in Knox, which Crosby said is the home of the only publicly owned Lombard Log Hauler in the state.

This is the second year that students have worked on the old steam-powered log hauler. The machine was patented by a Waterville man in 1901 and has crawler treads and skids in front for steering.

“This will hopefully be running someday, but it’s a major, major project,” Crosby said.

Though the fourth team had plans of creating a Stirling engine for use on the back of a canoe, they ended up with an engine model that can be built relatively inexpensively and used in classroom demonstrations to show thermal dynamic principles.

“The design is quite simple,” said senior mechanical engineer Dave Smart. The team used a bike speedometer from Wal-Mart and other inexpensive parts to measure the engine’s efficiency.

“We don’t know of anyone in the country that can do what this one is doing – measure the efficiency,” Crosby said.

A Maine author, who requested that her name not be used, provided inspiration for another project. She suffers from dysautonomia, a condition in which blood flow is impeded and forces her to stay in a prone position most of the time. Last summer, the author went to the university to see if someone there could help her.

“She really can’t use her [computer] lying down,” Crosby said. The team designed a computer work station that includes a robotic arm and a seat that moves up and down that allows her to literally work while she’s flat on her back. They plan to give their invention, which would sell for about $2,000, to the author later this week.

“This project could impact the 800,000 people with this disability, if not more people around the world,” team member Matt Tassinari said.

For mechanical engineers, senior projects are a graduation requirement, and as a UMaine tradition are almost always “new and different,” Crosby said. “The strength of this program is the making it work part.”