|
|
     |
|
|
|
by Christen Opsal
The team of University of Minnesota-Duluth industrial engineering students who took first place in the American Society of Mechanical Engineers (ASME) 2001 International Student Design Contest may owe their win to their strict adherence to a fundamental principle of innovation: Keep it simple, stupid. Then-seniors Joseph Higgins and Michael Anderson triumphed in the face of a complicated problem with extensive contest specifications and competitors with sophisticated-looking devices because they persisted in their quest to solve the problem in the simplest way they could find.
The Challenge
The problem was anything but simple. Student members of ASME from around the world were asked to "design and demonstrate a well-tested, cost-effective, and reliable prototype apparatus which would allow a quadriplegic (someone with total or near total paralysis from the shoulders down) to cast accurately a fishing lure using a specified rod and reel."
According to the contest statement, while quadriplegics have access to sip-and-puff technology for wheelchairs and other everyday assistive devices, "a definite need still exists for outdoor sports equipment which integrates sip-and-puff technology for control of the device." The problem asked ASME student members "to demonstrate the potential of mechanical and electronic technologies to meet the recreational needs of a part of the disabled population."
In recent years, others have attempted to solve this problem. A fishing rod and reel for people with disabilities is available, but it still needs to be cast by someone with full use of their arms. Several other devices are available for people who have the use of one arm. But a rod-and-reel system that allows a quadriplegic to cast a fishing line and reel using only the mouth remained undeveloped until the ASME design contest organizers decided to make a contest out of it.
The Contest Rules
As though the problem itself wasn't enough of a challenge, ASME added some further criteria to define how it was to be solved.
The "specified rod and reel" turned out to be the "Snoopy Catch' Em Kit," available at Wal-Mart stores. Higgins notes that for the UM-D team this one rule was the most difficult to follow. He says the problem would have been easier to solve if the use of a more sophisticated rod and reel had been permitted. But that also may have exceeded the team's budget for contest supplies. They went through six Snoopy rod-and-reels!
The original problem required contestants to use sip-and-puff technology to control of the fishing rod and reel, but contest organizers later modified this rule because sip-and-puff sensors are expensive. In adaptive devices, sip-and-puff sensors trip switches that open and close electrical circuits, powering the device. Contest organizers decided that the fishing rod-and-reels entered in the contest could begin with the switches--in effect, rendering the sip-and-puff sensors "implied."
The switches were to be located on a control box connected to the rod and reel by an electrical cable. The control box could not contain any batteries or other power sources. The device itself, however, could be powered by no more than five electromagnetic devices including motors or solenoids, (magnetic devices that charge a coil to drive a piston upwards). To encourage of use of "inexpensive and robust off-the-shelf technology," contest organizers recommended a motor available at Radio Shack.
Excluding the rod and reel, the entire device had to fit into a Popular Mechanics 16-inch toolbox prior to its assembly. Higgins says that by the final competition, they could have fit three of their devices in the box.
At the contests, team members had to fasten their device to a pole mounted on a mock "dock"--a square platform of plywood. Then, one team member, seated on the dock, had to cast the device using only the control box. Each team got two tries at three targets marked on the floor in front of the dock. The line connected to the lure had to be fully retrieved by the reel after each cast. The "lure," a 40mm x 60mm cloth bag filled with 20g of sand, was provided for each team. The score was based on the distance between the lure and the target. The team with the lowest combined score would be declared the winner.
The Winning Device
As Higgins and Anderson experimented with different ways to solve the problem, they kept trying to translate their complicated ideas in simple terms. According to Higgins, "There's got to be an easier way" became their mantra. "Some ideas just didn't make sense."
They finally designed a device powered by a solenoid and directed with three switches. It took four steps to cast and retrieve the device. (See photo.) Pressing button #1 (closing circuit #1) engages the solenoid. Pressing button #2 (closing circuit #2) brings the rod back. Releasing button #1 (opening circuit #1) releases the solenoid, sending the rod forward in a casting motion. Once a fish has been caught, pressing button #3 (closing circuit #3) reels it in.
The team's device actually went through two incarnations. The first clunky, inefficient version was demonstrated at the seven-state regional competition held in March 2001. Higgins says it resembled "a spider web of duct-taped wires." The streamlined model that Higgins and Anderson brought with them to the finals in New York City last November was downright primitive in contrast to some of the other 12 devices. One team's device used a digital camera to "sight" the targets. A team of students from India--the only international team to make it to finals--attached a telescope to their device for the same purpose. Other devices cast "underhand" or to the side. One even utilized custom-made gears.
Remarkably, all the devices that made it to finals worked well. But the two guys from Duluth still topped them all with a score of 218. The runner-up, Old Dominion University of Virginia, had 242. The last place team, New Mexico State University, scored a whopping 1318.
What's Next?
Higgins and Anderson hope to eventually market their device. In the meantime, they will replace the Snoopy rod-and-reel and continue to simplify. The device still has to be adapted for use by quadriplegics or others with limited use of their limbs through "sip-and-puff" sensors, head paddles, or a voice-activated computer program. And there's still the problem of how to get the fish off the hook. Maybe ASME will make that the next design problem.
FOR MORE INFORMATION:
www.asme.org/students/Competitions/designcontest/2001/Y2001index.html
www.tecsol.com.au/SwitchSuckBlow.htm
www.geocities.com/higginsj3
