Apple is working on ways to move the battery in the Apple Watch to provide haptic feedback to the wearer. Apple is continuing its efforts to make the Apple Watch thinner, this time in hopes of removing support for the standalone Taptic engine. Rather than letting the engine take up space, Apple is looking into whether the battery can do double duty as a source of haptic feedback.
Apple’s newly awarded patent for “Portable Electronic Device with Mobile Battery Element Haptic Device” is the latest in a long line of attempts to relocate the haptic engine. Apple has previously considered using a haptic wristband and has considered modifying the charging coil to do the same thing.
Traditionally, electronic devices include one or more buttons or electromechanical switches for providing input, and some devices include a touch sensor or touch screen for receiving input, Apple said in the patent. However, touch sensors often lack mechanical feedback to alert the user that the input has been registered.
The description in this patent application is for a haptic device that moves a battery element to generate tactilely perceptible pulses or vibrations along the outer surface of the device. This means there is a battery “electrically connected” to the display and a “coil assembly” that is configured to induce 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 potentially use that space for other reasons. Specifically, Apple notes that the current watch battery elements may be smaller than when the haptic device is not included, reducing possible battery life. Much of the patent is about the physics of what has to be done to the battery and how much it has to move to be effective.