Haptically-enabled system with braking

#One embodiment of the present invention is directed to an actuator. More particularly, one embodiment of the present invention is directed to a drive circuit for an actuator used to create vibrations on a haptically-enabled device.

#Electronic device manufacturers strive to produce a rich interface for users. Conventional devices use visual and auditory cues to provide feedback to a user. In some interface devices, kinesthetic feedback (such as active and resistive force feedback) and/or tactile feedback (such as vibration, texture, and heat) is also provided to the user, more generally known collectively as “haptic feedback” or “haptic effects.” Haptic feedback can provide cues that enhance and simplify the user interface. Specifically, vibration effects, or vibrotactile haptic effects, may be useful in providing cues to users of electronic devices to alert the user to specific events, or provide realistic feedback to create greater sensory immersion within a simulated or virtual environment.

#Haptic feedback has also been increasingly incorporated in portable electronic devices, such as cellular telephones, smartphones, portable gaming devices, and a variety of other portable electronic devices. For example, some portable gaming applications are capable of vibrating in a manner similar to control devices (e.g., joysticks, etc.) used with larger-scale gaming systems that are configured to provide haptic feedback. Further, devices such as smartphones use haptic effects to cause “buttons” on a touchscreen to feel like their mechanical counterparts when selected by a user.

#FIG. 1 is a block diagram of a haptically-enabled system in accordance with one embodiment of the present invention.

#FIG. 2 is a partial perspective view of an ERM embodiment of the actuator of FIG. 1 in accordance with one embodiment of the present invention.

#FIG. 3 is a circuit diagram of an actuator drive circuit in combination with the actuator of FIG. 1 in accordance with an embodiment of the present invention.

#One embodiment is a drive circuit that provides a programmable shorting load across an actuator/motor. The activation of the shorting load when the actuator is spinning brakes the actuator by stopping the spinning after a relatively short time duration without the need to apply a reverse polarity voltage.

#FIG. 1 is a block diagram of a haptically-enabled system 10 in accordance with one embodiment of the present invention. System 10 includes a touch sensitive surface 11 or other type of user interface mounted within a housing 15, and may include mechanical keys/buttons 13. Internal to system 10 is a haptic feedback system that generates vibrations on system 10. In one embodiment, the vibrations are generated on touch surface 11.

#The haptic feedback system includes a processor or controller 12. Coupled to processor 12 is a memory 20 and an actuator drive circuit 16, which is coupled to an actuator 18. Actuator 18 can be any type of Direct Current (“DC”) motor, and in one embodiment is an Eccentric Rotating Mass (“ERM”) actuator. Processor 12 may be any type of general purpose processor, or could be a processor specifically designed to provide haptic effects, such as an application-specific integrated circuit (“ASIC”). Processor 12 may be the same processor that operates the entire system 10, or may be a separate processor. Processor 12 can decide what haptic effects are to be played and the order in which the effects are played based on high level parameters. In general, the high level parameters that define a particular haptic effect include magnitude, frequency and duration. Low level parameters such as streaming motor commands could also be used to determine a particular haptic effect. A haptic effect may be considered “dynamic” if it includes some variation of these parameters when the haptic effect is generated or a variation of these parameters based on a user's interaction.