Layered Tactile Knob Structure for Clear, Stable Haptic Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing tactile presentation devices face challenges in providing a clear and stable tactile sense while minimizing vibration attenuation and maintaining contact area, as materials with high shear and compressive deformation often exhibit significant vibration attenuation.
Innovation Solution
A tactile presentation device with a tactile presentation knob that includes a surface layer and an inner layer, where the surface layer undergoes greater shear deformation and compressive deformation than the inner layer, generating a tactile sense through frictional force changes and voltage signals of different frequencies applied to electrodes, enhancing tactile feedback without significant vibration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a single-material conductive elastic portion is used, then the structure is simple, but it cannot achieve both clear tactile sense and stable tactile strength simultaneously
Solution Approach 1:
The conductive elastic portion is divided into two distinct layers: a surface layer (first conductive elastic portion) and an inner layer (second conductive elastic portion). Each layer has different material properties optimized for specific functions - the surface layer provides clear tactile feedback through higher shear deformation, while the inner layer ensures stable contact through higher vibration transmissibility and compressive deformation capability.
Solution Approach 2:
Different regions of the conductive elastic portion are assigned different material characteristics. The surface layer uses material with higher shear modulus for clear tactile sensation, while the inner layer uses material with higher vibration transmissibility for stable contact maintenance. This local differentiation allows each region to optimize its function.
2Ease of operation
If material with high shear and compressive deformation is used, then tactile feedback is enhanced, but vibration attenuation increases significantly
Solution Approach 1:
The vibration transmission path is segmented into two layers with different damping characteristics. The surface layer accepts shear deformation for tactile feedback generation, while the inner layer with higher vibration transmissibility efficiently transmits the resulting vibrations to the user, minimizing energy loss in the transmission path.
Solution Approach 2:
The inner layer acts as an intermediary between the operation screen and the user's finger. It receives vibrations from the surface layer and efficiently transmits them to the user while maintaining stable contact, serving as a vibration transmission medium that reduces overall system attenuation.
3Shape
If the operation screen has smooth surface for design purposes, then aesthetics are improved, but tactile detection of switch positions becomes difficult
Solution Approach 1:
The patent replaces reliance on mechanical surface features (asperities, unevenness) with an electrostatic-based tactile presentation system. Voltage signals applied to the conductive elastic portion generate electrostatic forces that create tactile sensations on the smooth surface, substituting mechanical texture with electrostatic field effects.
Solution Approach 2:
The system changes the operating parameters of the operation screen by applying time-varying voltage signals to different regions. This creates dynamic electrostatic forces that generate tactile sensations corresponding to switch positions, enabling tactile detection without altering the physical surface geometry.
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 device provides a clear and stable tactile sense by propagating vibrations effectively, maintaining contact area stability, and reducing the impact of operation surface flatness and roughness on tactile feedback.
Implementation Method 1
a voltage generation circuit that generates a first voltage signal of a first frequency and a second voltage signal of a second frequency different from the first frequency... The tactile sense is presented by supplying the first voltage signal and the second voltage signal to generate a frictional force between the operation screen and the tactile presentation knob
Implementation Method 2
The surface layer is set to be subjected to greater shear deformation than the inner layer by an operation of the tactile presentation knob, to generate a vibration by a change in the frictional force
Implementation Method 3
The inner layer is set to have higher vibration transmissibility than the surface layer
Data Source
AI summary
The present disclosure relates to a tactile presentation device that includes a tactile presentation knob placed on an operation screen and for presenting a tactile sense to a user via the tactile presentation knob. The tactile presentation knob includes a conductive elastic portion that includes a surface layer facing the operation screen and an inner layer located on the side opposite to the operation screen, and an operation part that fixes the conductive elastic portion. The surface layer is set to be subjected to greater shear deformation than the inner layer by an operation of the tactile presentation knob, to generate vibrations by a change in the frictional force, and to be subjected to greater compressive deformation than the inner layer by a press of the tactile presentation knob. The inner layer is set to have higher vibration transmissibility than the surface layer.