Wearable Optical Sensors for Indirect User-Interface Force Localization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wearable computing devices lack efficient methods to determine the location of a force applied to a user interface without relying on touch-sensitive displays, which can increase complexity and power consumption.
Innovation Solution
The wearable computing device uses optical sensors, such as photoplethysmography (PPG) sensors with LEDs and detectors, to indirectly sense the location of a force applied to a user interface by analyzing optical readings and applying loss functions to estimate the force location, allowing for non-touch sensitive interactions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If touch-sensitive displays are used to determine force location, then user interaction accuracy is improved, but device complexity and power consumption increase
Solution Approach 1:
The patent replaces touch-sensitive display technology with optical sensing technology. Instead of using a touch-sensitive display to detect force location, the system uses optical sensors (LEDs and photodetectors) to detect changes in optical properties of tissue when force is applied, thereby substituting a mechanical/electrical sensing system with an optical sensing system that is simpler and more power-efficient.
Solution Approach 2:
The patent introduces tissue as an intermediary medium between the force application point and the sensors. The optical sensors detect force location indirectly by measuring changes in optical properties (absorption, scattering) of the tissue beneath the force application point, rather than directly sensing the force on the display surface.
2Measurement precision
If touch-sensitive displays are used to determine force location, then user interaction accuracy is improved, but power consumption increases
Solution Approach 1:
The patent replaces the power-intensive touch-sensitive display system with a low-power optical sensing system. The optical sensors consume significantly less power while achieving the same force location determination functionality through non-contact optical measurements of tissue properties.
Solution Approach 2:
The patent utilizes the body's own tissue optical properties as the sensing medium. The tissue itself serves as the sensor by naturally exhibiting changes in optical absorption and scattering when subjected to force, eliminating the need for additional active sensing components that would consume power.
3Measurement precision
If touch-sensitive displays are used to determine force location, then user interaction accuracy is improved, but device size increases
Solution Approach 1:
The patent makes the optical sensing system multi-functional by using the same optical sensors for both force location determination and other physiological measurements. This eliminates the need for separate touch-sensitive display components, reducing overall device volume while maintaining force location accuracy.
Solution Approach 2:
The patent uses tissue as an intermediary that enables force detection without requiring additional hardware layers. By detecting optical property changes in the tissue, the system achieves force location sensing without adding the bulk of touch-sensitive display components.
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 approach reduces the need for touch-sensitive displays, conserves power, and enables a more compact design while accurately determining user interactions, enhancing usability and functionality.
Implementation Method 1
The sensors may include photoplethysmography (PPG) sensors configured to monitor a heart rate of the user when the wearable computing device is worn by the user
Implementation Method 2
sensors which are disposed on the lower side of the housing and are configured to output one or more optical readings when a force is applied to the user interface
Data Source
AI summary
A wearable computing device includes a housing having an upper side and a lower side, where the lower side of the housing is opposite to the upper side of the housing and is configured to be in contact with a body part of a user when the wearable computing device is worn by the user. The wearable computing device further includes a user interface disposed on the upper side of the housing. The wearable computing device further includes sensors, disposed on the lower side of the housing, which output one or more optical readings when a force is applied to the user interface. The wearable computing device further includes one or more processors which determine a location at which the force is applied to the user interface based on the one or more optical readings output by the sensors.