The Robot That Rolled Sideways
The robotics club had only one week left before the regional contest, and their robot, Biscuit, had a serious problem. Every time it was instructed to roll straight forward, it drifted toward the left, as if some invisible force were nudging it along. By Tuesday afternoon, it had bumped into the same wall four separate times.
Devon, the club captain, stared at the code on his laptop and insisted that he had read every line without finding a single mistake. Priya, who usually stayed quiet during meetings, suggested that perhaps the code was fine and the robot itself was the trouble. She crouched beside Biscuit and spun each wheel with her finger. The right wheel turned smoothly, but the left wheel made a faint scratching sound and stopped much sooner.
"Something is rubbing," she said.
Devon frowned. He had been so certain that the problem was his programming that he had never examined the machine itself, and he felt a little embarrassed. Even so, he handed Priya the screwdriver.
She removed the wheel and discovered a long strand of hair wrapped around the axle, wound so tightly that it dragged against every turn. It took her less than one minute to cut it free.
They placed Biscuit at the starting line and pressed the button. The robot rolled forward in a perfectly straight line and stopped an inch from the wall.
Devon laughed and admitted that he had spent three whole days repairing the wrong thing. Priya reminded him that his code was the reason the robot moved so precisely once the wheel was fixed, because the team had needed both. On Saturday, they traveled to the contest together, with Biscuit riding carefully in a box on Priya's lap.