Piezoelectric Transducers for Tactile Feedback and Gesture Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Portable electronic devices with touch-sensitive displays face challenges in providing both tactile feedback and detecting contactless gestures without increasing component costs or complexity.
Innovation Solution
Incorporating a plurality of piezoelectric patch transducers beneath the display, which can switch between tactile feedback mode and object detection mode, using the same transducers to provide tactile feedback and detect contactless positions via acoustic signals, and processing these signals to determine three-dimensional gestures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If separate components are added for contactless gesture detection, then detection capability is improved, but device complexity and cost increase
Solution Approach 1:
The piezoelectric patch transducers are designed to perform multiple functions: they provide tactile feedback when the user touches the display and detect contactless gestures when the user's hand is near the display but not touching it. This multi-functionality eliminates the need for separate detection components, reducing device complexity while maintaining enhanced adaptability.
Solution Approach 2:
The system dynamically switches the transducers between two operational modes based on detected touch conditions. When touch is detected, the transducers operate in tactile feedback mode. When no touch is detected but the hand is nearby, the system switches to object detection mode to identify contactless gestures. This dynamic mode switching enables a single component to adapt its function based on operational context.
2Ease of manufacture
If piezoelectric patch transducers are used for both tactile feedback and object detection, then component cost is reduced, but functional complexity increases
Solution Approach 1:
A single type of piezoelectric patch transducer is used for both tactile feedback and contactless gesture detection, eliminating the need for multiple different components. This universality reduces manufacturing cost while the controller manages the functional complexity by switching between modes.
Solution Approach 2:
The controller dynamically configures the transducers' operational mode based on touch detection status. This dynamic control allows the same hardware component to serve different functional purposes at different times, reducing the need for multiple specialized components and lowering overall system cost.
3Adaptability or versatility
If transducers operate in object detection mode continuously, then contactless gesture detection is available, but energy consumption increases
Solution Approach 1:
The system dynamically adjusts transducer operation based on contextual conditions. The transducers operate in tactile feedback mode during normal touch interaction, then switch to object detection mode only when no touch is detected but the hand is nearby. This dynamic mode switching ensures contactless gesture detection is available when needed while minimizing energy consumption during normal operation.
Solution Approach 2:
The controller periodically monitors touch status and switches transducer modes accordingly. Rather than continuous operation in detection mode, the system uses periodic checking of touch conditions to determine when to activate contactless gesture detection, reducing overall energy consumption while maintaining availability when required.
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
Enables enhanced user interaction with tactile feedback and contactless gesture detection without additional components, improving user interface functionality while maintaining cost-effectiveness.
Implementation Method 1
a plurality of piezoelectric patch transducers disposed beneath the display
Implementation Method 2
each of the plurality of piezoelectric patch transducers is driven with a varying voltage to produce an ultrasonic signal that is output to the uniquely associated acoustic port
Implementation Method 3
provide acoustic detection of a contactless position of an object relative to the device
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An electronic device (100) includes a touch-sensitive display (118), and a plurality of piezoelectric patch transducers (210) disposed beneath the display. A controller (212) is configured to switch each of the transducers between a tactile feedback mode to provide tactile feedback via the touch-sensitive display, and an object detection mode to provide acoustic detection of a contactless position of an object (218) relative to the device. The object is free of contact with the device at the contactless object position. Using the same transducers to provide tactile feedback and object detection provides these features without additional costs associated with adding further components. A microphone (130) of the device can receive ultrasonic signals (f1,f2), emitted from the transducers and via associated acoustic ports (214), and the device can process the received signals to determine a contactless three-dimensional gesture that is performed, for example above the display.