Apple Insider reports that Apple is studying how to make the battery in the Apple Watch move to provide haptic feedback to the wearer.
Apple is continuing its efforts to make the Apple Watch thinner, this time to eliminate the need for a separate Taptic engine. Rather than make the engine take up more space, Apple wanted to see if it could allow the battery to double as a source of haptic feedback.
The newly granted patent “Portable Electronic Device with Haptic Device with Moving Battery Element” is the latest in many attempts to reposition the haptic engine. Apple had previously considered a haptic wristband and considered modifying the charging coil to do the same thing.
In each case, the object is the same. Apple is always looking for ways to take the components it can’t live without and make them do more.
“Traditionally, electronic devices include one or more buttons or electromechanical switches for providing input,” the patent application says. “Some devices include a touch sensor or touchscreen for receiving input. However, touch sensors often lack mechanical feedback to alert the user that the input has been registered.”
“The description in this patent application] is directed to a haptic device that moves a battery element to generate haptically perceptible pulses or vibrations along the outer surface of the device,” it continued.
This means having a battery “electrically coupled to the display”, and a “coil assembly” “configured to cause oscillating motion of the battery element parallel to the display to produce a haptic output”.
In addition to potentially eliminating the need for a separate haptic engine to save space on the Apple Watch, Apple could use that space for other reasons. Specifically, Apple notes that the current Apple Watch has “possibly smaller battery elements than if the haptic device were not included, reducing possible battery life.”
Most of the patent filings deal with the physics of the battery and how much it has to move to be effective.
“The less mass a haptic device has, the farther the haptic device may need to move to produce the same haptic output,” it said. “For example, to produce the same magnitude of haptic output, a first mass as large as a second mass can travel twice as far.”
So currently the haptic engine itself takes up space and then takes up more space due to the need to move. “Thus, even if the mass is smaller to accommodate the larger battery element, the additional space required for the haptic device to move the mass may still limit the space available for the size of the battery element.”
“A larger battery element may require a smaller haptic device that may not have enough mass and/or move the mass far enough to produce the desired magnitude of haptic output,” Apple said.
The patent, which attempts to propose a solution to this balance between component size and function, is credited to six inventors, including Erik G. de Jong. Its previous related work includes a patent covering a method of utilizing an Apple Watch strap to provide a hidden battery.