Apple is continuing its efforts to make the apple watch thinner, this time hoping to eliminate the independent taptic engine. Instead of letting the engine take up space, apple is studying whether the battery can undertake dual tasks and become a source of tactile feedback.
Apple's newly patented "portable electronic device with mobile battery element tactile device" is the latest of many attempts to relocate the tactile engine. Previously, Apple had considered using a tactile wristband and modifying the charging coil to do the same.
Apple said in the patent that traditionally, electronic devices include one or more buttons or electromechanical switches to provide input, and some devices include a touch sensor or touch screen to receive input. However, touch sensors usually lack mechanical feedback and cannot remind the user that the input has been registered.
The description in this patent application is for a tactile device that can move battery elements to generate tactile pulses or vibrations along the outer surface of the device. This means that there is a battery "electrically connected to the display" and a "coil assembly" configured to induce oscillating motion of the battery element parallel to the display to produce tactile output.
In addition to the possibility of eliminating the need for a separate haptic engine to save Apple watch space, Apple may use the space for other reasons. Specifically, apple pointed out that the current watch battery components may be smaller than when the tactile device is not included, reducing the possible battery life. Most of the patent is about physics, that is, what must be done to the battery and how much it must move to be effective.