"How am I going to take all this chalkboard stuff I planned to do and robotics stuff and make it work?" Everbach asked himself.
But for the easygoing junior, once he had decided to become an engineer, it was just another problem to solve. Doing anything else "never even occurred to me," he said. "I wanted to do engineering and it never seemed that blindness should ever stop me."
The result has been a project that has required enough gadgetry - some of it high-tech but much of it jury-rigged out of toys - to fuel a James Bond movie. In the end, the plotline of Dahmm's success at Swarthmore comes off more as a buddy flick, as supportive mentors including Everbach, his classmates, and even a trusty dog named Fathom all work on the fly to figure out something none of them knew two years ago.
"I really can't do it without these people," said Dahmm, 20, although he quickly added, "What I'm trying to figure out is, how can I do it without these people."
Doors are opening
Engineering isn't a field that traditionally had many blind workers, but that is changing as technology opens doors, said Melanie Brunson, executive director of the American Council of the Blind.
No one keeps track of the numbers, but Dahmm said he met a blind engineer who works for the Army Corps of Engineers in New York and another at Purdue University.
"There are role models out there," he said.
Dahmm and his mother trace his unwavering determination to the maternity ward.
Twenty years ago, Dahmm and his twin brother, Ethan, were born three months premature and grossly underweight. They were treated with pure oxygen under white lights that caused retinal detachment in both brothers and that led to even more severe ailments - cerebral palsy, epilepsy, and blindness for Ethan.
Their mother, Cynthia Murray, 55, said a nurse told her Hayden "would never be a rocket scientist."
"I was beyond livid," Murray recalled. "I will never forget that. I was so angry that somebody wanted to predict where my kids were going." At the time, a doctor also said Ethan would likely spend his life in a vegetative state.
Both twins vastly exceeded the grim early expectations. Although Ethan uses a wheelchair and has verbal and cognitive difficulties, he attends Overbrook School for the Blind and "can recite poetry better than anyone I know," said his adoring younger-by-two-minutes brother.
Ethan's disabilities have caused Hayden to reflect on his own struggles in a different light. "Living with Ethan has taught me to appreciate everything," he said.
Though Hayden was legally blind, art was an early passion. His love of cartooning and the publicity he received in The Inquirer for his white-porcelain, plunger-hurling, crime-fighting comic book hero fueled his initial dream of becoming a Disney animator.
But the ensuing years brought loss and disappointment. Their father died of a heart attack when the twins were 12. And Hayden was losing his vision, first in his right eye and then, near the end of high school, in his left as well.
"When he got to the point where he couldn't see to do artwork, it was hard for him to admit," his mother said. "But he has such a great perspective he didn't bemoan it. He said, 'OK, I'm going to focus elsewhere.' "
Elsewhere was science and engineering, geared toward solving environmental problems "with a direct application to the community in a way that could benefit people," he said.
Dahmm's ability to excel even while going blind astounded his teachers.
"He's a sponge. He just learns stuff," marveled John Tierno, a Springfield High guidance counselor. "He took five [Advanced Placement] courses in his senior year and had the best grades in every class."
Starting college with no vision was "a little anxiety-producing," Dahmm said. "I was bumbling around with a cane. I didn't even know braille that well."
Also challenging was "how to bring engineering into Hayden's world by hearing and touch," Everbach said.
Over the next two years, a village of helpers - engineers at Drexel and Penn, Swarthmore students, even Everbach's son - came up with solutions that went beyond the screen reader on Dahmm's computer.
They made Lego models and developed plastic pieces equipped with braille notation that represented electrical voltage and current sources. Using the models, Dahmm could visualize diagrams drawn on the blackboard.
They also created a gadget that enables numerical data to be converted to a series of sounds, which Dahmm can listen to and translate back into data. Others take notes for him and translate homework problems.
"They're 'the homework whisperers,' " Dahmm said.
But Dahmm also needed one last element to complete the equation: his guide dog, Fathom, a yellow Lab/golden retriever with soft fur and amber eyes that he acquired last year and adores. Dahmm and his dog share a double room on campus, where Fathom sleeps underneath his companion's bed.
He calls Fathom "the best roommate on campus," adding, "It would be creepy if any other roommate, when you come back from the bathroom, runs circles around you and licks your face."
Dahmm seems to have little doubt that he and Fathom will find new adventures when he earns his degree in 2015.
"This is the best time to be blind," he said with characteristic optimism. "If you go back to Louis Braille or Helen Keller, they didn't have screen readers. The best career option was to be a beggar on the street. I'm grateful I'm able to witness this wave of technology and have the potential to contribute to it."