Mechanical engineering student Alexander Holthaus and Randy Coffman, of Adaptive Sports Center, stroll the harbor at Morro Bay. Click on the photo to see a gallery.
With the majestic Morro Rock providing a scenic backdrop, mechanical engineering senior Alexander Holthaus slowly drifts from shore on a stand-up paddleboard powered by a man in a wheelchair.
The man in the chair is not disabled, but the senior project he sponsored will be used to help several people who visit his Adaptive Sports Center in Shaver Lake.
“There’s a lot of interest from our spinal cord injury groups and our amputees to go out on a paddleboard rather than a kayak,” said Randy Coffman, executive director of the center, which provides year-round adaptive recreation in the Central Sierra Nevada.
Coffman was at the center, he said, when someone from Cal Poly’s College of Engineering visited and asked if he had any projects for seniors. “And I said, ‘I have a whole bunch of them.’”
Each fall, students are paired with senior projects they will work on the entire school year. This year, Coffman’s Paddleboard for All Persons was one of more than 40 projects presented to seniors in the Mechanical Engineering Department. A team of seniors took on the challenge, including Holthaus, Sean Yueh, Garrett Holmes and Garett Jones.
“I love projects that are outdoor-focused,” Holthaus said. “And I love the fact that our project is going to directly help someone.”
Not just one, though. A significant feature of the project is that it can be used by a number of people with different disabilities and levels of mobility – something that will come in handy at Adaptive Sports.
For Coffman’s customers, kayaking sometimes causes friction against their skin, leading to blisters. While there are currently adaptive paddleboards on the market, they often feature parts that are fixed onto the board – and they cost around $7,000 apiece.
“The expense of the commercial board has just gotten beyond the reach of most adaptive sports centers,” Coffman said.
The one designed at Cal Poly can be adjusted and modified for each user. Instead of drilling holes into a board and bolting a chair, which limits its usage and buoyancy, the students created a pontoon that attaches to a paddleboard with Velcro straps. A wheelchair or even a rail for standing can then be strapped to the pontoon.
“You could probably put a lawn chair on there and strap it down,” said mechanical engineering lecturer Sarah Harding, who advised the team.
The pontoon width itself is adjustable to match the balance and skill level of the users.
“Mostly it’s going to be amputee or paraplegic users,” Holthaus said. “That’s the primary customer base of the nonprofit. They’re working with a lot of veterans that have come back with combat injuries.”
The project posed several challenges to the students.
“There’s a lot of layers in this project,” Harding said.
Aside from machining, the students used Harding’s 80-year-old Singer sewing machine to piece together Velcro. George Leone, the retired manager of the Cal Poly aero hangar – and a longtime surfboard maker – helped with some of the composites.
“Making fiberglass was like nothing we’ve ever experienced before,” Holthaus said.
The students also created a ramp that wheelchair users can employ to get on the board.
“The ramp will make it so you don’t have to pick up wheelchair users and put them on the board,” Harding said.
Student creation will help wheelchair users enjoy paddleboarding.
Afterward, Coffman took it to Shaver Lake. There, Holthaus said, the student creation will help others enjoy the outdoors – and get some valuable upper body exercise.
“It’s a way to go out and experience something that’s difficult to do if you’re a wheelchair user.”
A few weeks later, Coffman said the center had already used the paddleboard in one of its programs, and it worked, "Perfectly."