Halbach Array Haptic Actuator for Dual-Axis Feedback

Solution Overview

Problem

Current haptic technologies face limitations in providing efficient dual-axis tactile feedback, particularly in wearable devices, as they often rely on single-axis actuators that fail to deliver localized and nuanced vibrations effectively across both x-axis and z-axis directions.

Innovation Solution

A haptic actuator design incorporating a Halbach array of permanent magnets and interleaved coils within a housing, coupled with flexure members and a controller, allows for movement along both x-axis and z-axis directions, enabling dual-axis haptic feedback through controlled magnetic fields and Lorentz forces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If single-axis actuators are used, then device complexity is reduced, but haptic feedback capability is limited to one direction

Engineering Contradiction:

Improvehaptic feedback capabilityVSAvoidactuator structure

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent combines multiple coil assemblies (first and second coil assemblies) with a shared magnet assembly into a single integrated dual-axis haptic actuator. This merging approach enables both x-axis and z-axis haptic feedback capabilities while reducing overall device complexity compared to using separate single-axis actuators.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The magnet assembly serves multiple functions by interacting with different coil assemblies to generate haptic feedback in multiple directions. The same magnet assembly can be actuated by different coils to produce vibrations along both x-axis and z-axis, making the actuator structure universal and multi-functional.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Manufacturing precision

If dual-axis actuators are implemented, then localized and nuanced vibrations are improved, but magnetic leakage increases

Engineering Contradiction:

Improvevibration localizationVSAvoidmagnetic leakage

Core Design Contradiction:

Manufacturing precisionVSObject-generated harmful factors

Solution Approach 1:

The patent extracts and separates magnetic field management into distinct components: ferritic shields are specifically introduced to contain and direct magnetic fields, preventing magnetic leakage while maintaining the dual-axis vibration capability. This extraction approach isolates the magnetic field management function from the actuation function.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

Ferritic shields act as intermediary elements between the magnet assembly and the external environment. These shields mediate the magnetic field by containing it within the actuator structure, preventing harmful magnetic leakage while allowing the magnetic field to effectively actuate the coils for precise vibration localization.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Measurement precision

If multiple coils are used for dual-axis control, then haptic precision is improved, but energy consumption increases

Engineering Contradiction:

Improvehaptic control precisionVSAvoidcoil energy consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent inverts the conventional approach by using a shared magnet assembly that is actuated by multiple coils, rather than using multiple independent magnet assemblies. This inversion allows the same magnetic field source to be controlled by different coil configurations, achieving dual-axis precision while reducing total energy consumption through shared magnetic components.

Inventive Principle:

Principle #13The other way round (Inversion)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This design enhances the capability to provide localized and nuanced vibrations, enabling more effective communication of information through tactile feedback, such as message alerts with varying durations and types, while reducing magnetic leakage and improving efficiency compared to single-axis actuators.

Implementation Method 1

A haptic actuator design incorporating a Halbach array of permanent magnets and interleaved coils within a housing, coupled with flexure members and a controller, allows for movement along both x-axis and z-axis directions, enabling dual-axis haptic feedback through controlled magnetic fields and Lorentz forces.

Methodology Applied

Scientific EffectLorentz force: Lorentz Force

Implementation Method 2

A haptic actuator design incorporating a Halbach array of permanent magnets and interleaved coils within a housing, coupled with flexure members and a controller, allows for movement along both x-axis and z-axis directions, enabling dual-axis haptic feedback through controlled magnetic fields and Lorentz forces.

Methodology Applied

Scientific EffectMagnetic field interaction: Magnetic Field

Data Source

PatentUS10671166B2Electronic device including Halbach array based haptic actuator and related methods

Publication Date: 2020.06.02 APPLE INC

AI summary

An electronic device may include a haptic actuator. The haptic actuator may include a haptic actuator housing, at least coil carried by the haptic actuator housing, and a Halbach array of permanent magnets movable within the haptic actuator housing responsive to the at least one coil. The electronic device may also include a controller coupled to the at least one coil.