Piezo Trackpad Haptics Uniform Response

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional trackpads suffer from non-uniform response and inadvertent actuations, leading to inefficient and frustrating user interactions, especially when typing, due to their hinged structure and dome switch mechanisms.

Innovation Solution

An input device with a pressure sensor and haptic feedback mechanism using piezos to detect and quantify pressure, providing uniform haptic feedback and reducing inadvertent clicks by energizing the piezos based on the applied pressure, thereby enhancing user interaction accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a hinged structure with dome switch is used to implement trackpad functionality, then click initiation functionality is achieved, but the response is non-uniform and the upper region is difficult to click

Engineering Contradiction:

Improveclick initiation functionalityVSAvoidresponse uniformity

Core Design Contradiction:

Ease of operationVSManufacturing precision

Solution Approach 1:

The trackpad surface is divided into multiple independent sensing zones with discrete piezoelectric elements distributed across the surface, allowing each region to be independently actuated and sensed, thereby achieving uniform response across the entire surface including the previously difficult upper region

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The mechanical hinged dome switch structure is replaced with piezoelectric actuators and pressure sensors that provide direct electromagnetic-to-mechanical conversion, eliminating the non-uniform mechanical leverage issues inherent in hinged structures and enabling consistent actuation force distribution across the trackpad surface

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Productivity

If conventional hinged trackpad structure is used, then basic cursor control is achieved, but inadvertent actuations occur during typing causing cursor to jump

Engineering Contradiction:

Improvecursor control functionalityVSAvoidinadvertent actuation rejection

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The piezoelectric sensors provide real-time feedback on pressure magnitude and location, enabling the system to distinguish between intentional clicking gestures and inadvertent typing contacts, allowing selective activation of click functions only when pressure thresholds and patterns indicate deliberate user intent

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system monitors multiple pressure parameters including magnitude, duration, and rate of change to differentiate between intentional clicks and inadvertent contacts during typing, using dynamic threshold adjustments based on contextual pressure patterns to prevent false activations while maintaining responsive cursor control

Inventive Principle:

Principle #35Parameter changes

3Measurement precision

If piezos are used for pressure detection and haptic feedback, then uniform haptic feedback and accurate pressure detection are achieved, but device complexity increases

Engineering Contradiction:

Improvepressure detection accuracyVSAvoidpiezo integration complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The piezoelectric elements serve dual functions as both actuators for haptic feedback and sensors for pressure detection, eliminating the need for separate mechanical switch structures and reducing overall device complexity despite the advanced functionality provided

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The pressure sensing and haptic actuation functions are merged into a single integrated piezoelectric system, where the same elements that detect pressure also generate the haptic response, simplifying the overall device architecture by eliminating separate mechanical components for each function

Inventive Principle:

Principle #5Merging (Combining)

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

The solution provides a uniform and accurate haptic feedback mechanism that improves user interaction by reducing cursor jumping and enhancing the overall efficiency of trackpad usage, allowing for precise pressure detection and controlled haptic responses.

Implementation Method 1

one or more piezos configured to detect and quantify an amount of the application of the pressure to the outer surface by the object

Methodology Applied

Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

control the haptic feedback of the pressure sensor and haptic feedback mechanism by energizing the one or more piezos

Methodology Applied

Scientific EffectPiezoelectric effect: Piezoelectric Effect

Data Source

PatentUS10359848B2Input device haptics and pressure sensing

Publication Date: 2019.07.23 MICROSOFT TECHNOLOGY LICENSING LLC

AI summary

Input device haptics and pressure sensing techniques are described. An input device includes an outer surface, a pressure sensor and haptic feedback mechanism, and a pressure sensing and haptic feedback module. The outer surface is configured to receive an application of pressure by an object. The pressure sensor and haptic feedback mechanism has one or more piezos configured to detect and quantify an amount of the application of the pressure to the outer surface by the object, the one or more piezos configured to output a signal indicating the quantified amount of the pressure. The pressure sensing and haptic feedback module is configured to receive the signal from the one or more piezos indicating the quantified amount of the pressure and control the haptic feedback of the pressure sensor and haptic feedback mechanism.