Most smartwatches constantly pester their wearers about appointments, e-mails, or even calories they have left to burn. Aisen Caro Chacin, who teaches physical computing at the Parsons New School for Design in New York, has built one that doesn’t blast stressful reminders. Hers instead subtly augments her chronoception, or sense of time. Called Scent Rhythm, the wrist piece releases fragrances that she associates with waking up, being active, relaxing, and sleeping. “Olfaction and chronoception are both chemical senses, so I thought it would be interesting to map them onto one another,” Chacin says. Here’s what makes her watch tick.