"Right now, every day's a foggy day, even a bright sunny day," he told ABC7.
That fog is the result of a condition called macular degeneration.
"Macular degeneration blocks out your central vision. It's like trying to look through your fist," he described. "It makes it a little difficult to read street signs."
But, on this walk, Sullens got some help to find the street signs and his destination from a device more commonly found in cars. He is being trained to use a specialized GPS by therapists at the VA hospital in Palo Alto. The device, known as a Trekker, is adapted for use by the blind.
"What's different about it, is it's about the same size as a regular handheld device, but it's got a tactile keyboard overlay to allow them to access the informaion," explained Laura Koehler with the VA hospital in Palo Alto.
Using his sense of touch Sullens can cycle through a list of options. The GPS figures out where he is and he tells it where he wants to go. He demonstrated how he could get to Borders book store.
"I'm pushing enter to choose Borders bookstore," he said.
"Please head toward Waverly Street crossing Hamilton Avenue," the machine responded.
"And, off I go," said Sullens.
The device gave Sullens the shape and layout of the intersections he was crossing, but he still had to navigate the traffic and red lights using his own hearing and white cane. As he walked further along, the GPS began describing the neighborhood, giving him a chance to learn it the way a seeing person would.
"Union Bank of California, nearby. Palto Alto Sports shop and Toy World, on your left. Michael's Gelato and Cafe, on your right," the GPS stated, indicating various details about the trip.
"It's very freeing to be able to walk down the street and just explore the environment, something we take so for granted," Koehler explained.
The software is geared toward walking, and steers away from freeways and busy expressways that a normal GPS might favor. In about half an hour, Sullens was closing in on his mark.
"You have reached your destination. Borders, on your right," said the GPS.
"It's right here," said Sullens. "And, it's a nice open place to be. Voila!"
Once he masters the technology he will take the device and a new found sense of freedom back to his home in southern California.
"This is letting me out of the bottle, to give me the freedom to walk around my town," he said.