The print edition of The Economist came out with an interesting article on mobile haptics last week, which is now available online. It points out that the iPhone lacks what little haptic feedback a normal phone provides in favor of a touch screen, and notes that Samsung’s SCH-W559, not yet available in North America, will utilize an active haptic display. That product uses Immersion’s VibeTonz technology, which I haven’t felt. Although the vibration signal is said to be “very precise,” I find vibration motors to be heavy and bulky and always having a weaker transient response and resolution than other actuation methods. But the first generation of mobile haptics is already getting by with unbalanced motors, so it seems to make some sense to try to refine them until other actuators hit the market.
The article also interviews Vincent Hayward of McGill University’s Center for Intelligent Machines who has been developing skin stretching techniques to simulate tactile stimuli normal to the contact area. I saw him present his “THMB” system at the Enactive conference in Montreal, and it looked damn cool. (“Looked” not “felt,” because again… no demo. Maybe I’ll make an appointment to walk over there one of these days and check it out.) It’s a MEMS, positioned on the device to be felt by the tip of the thumb (essentially the same place as Sony’s scroll wheel).
Speaking of which, I recently read about Sony’s own moble vibrotactile platform, which it calls the TouchEngine—an extremely thin vibration actuator made out of piezoelectric film. But it’s not for the thumbtip; it’s installed on the back of the device, and sits in contact with the user’s palm.