Touch Display Acceleration Sensor With Fingertip Force Simulation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing technologies face challenges in precisely measuring and comparing the effectiveness of haptic feedback on touch displays due to variations in mass, actuator forces, surface deflection, and user fingertip forces, lacking a standardized tool to accurately determine the acceleration of touch display surfaces.

Innovation Solution

A sensor unit is designed to measure the acceleration of touch display surfaces with an adjustable counterforce simulating fingertip force, comprising a housing, a contact element, a biasing spring, and an acceleration sensor, allowing precise and reproducible measurement of surface movements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If an accelerometer is used to measure vibration of a rotating shaft with a shaft rider biased by a coil spring, then low frequency vibration can be measured, but the device becomes complex and difficult to adapt for touch display surface acceleration measurement

Engineering Contradiction:
Improvevibration measurement capabilityVSAvoiddevice structure complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies the copying principle by creating a simplified sensor unit that replicates the essential measurement function of complex vibration monitoring devices. Instead of using a shaft rider with coil spring and accelerometer assembly, the patent uses a contact element with biasing element that copies the force application mechanism, combined with a simplified accelerometer arrangement that only measures surface acceleration directly without the complex intermediate structures.

Inventive Principle:
Principle #26Copying

2Reliability

If the mass of moving display parts is increased to improve haptic feedback effectiveness, then haptic feedback performance improves, but the actuator forces required increase and the system becomes less efficient

Engineering Contradiction:
Improvehaptic feedback effectivenessVSAvoidactuator energy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies parameter changes by using the sensor unit to precisely measure acceleration and thereby characterize the dynamic response of the touch display surface. This enables optimization of the relationship between actuator forces and resulting surface acceleration, allowing the system to achieve effective haptic feedback with optimized energy consumption by adjusting operational parameters based on measured acceleration characteristics.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If the surface deflection is increased to enhance haptic feedback, then user perception improves, but the forces required from actuators increase and the display structure may be damaged

Engineering Contradiction:
Improvehaptic feedback perceptionVSAvoiddisplay structure integrity
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent applies feedback by using the sensor unit to measure the actual acceleration and dynamic response of the touch display surface during operation. This measurement feedback enables the control system to adjust actuator forces in real-time, ensuring that surface deflection remains within safe limits while still providing perceptible haptic feedback, thereby preventing structural damage while maintaining user perception.

Inventive Principle:
Principle #23Feedback

4Adaptability or versatility

If different actuator forces are applied to achieve desired surface movement, then haptic feedback performance varies, but it becomes difficult to compare and specify effectiveness across different displays

Engineering Contradiction:
Improvehaptic feedback performance rangeVSAvoideffectiveness comparison capability
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent applies universality by designing a standardized sensor unit that can be applied to measure acceleration on any touch display surface regardless of the specific actuator forces or display configuration. This universal measurement tool enables precise comparison and specification of haptic feedback effectiveness across different displays, eliminating the difficulty of comparison caused by varying actuator forces.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 precise and standardized measurement of touch display surface acceleration, facilitating the comparison and optimization of haptic feedback performance across different displays.

Implementation Method 1

a biasing element configured to press the contact element against the touch display surface

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

an acceleration sensor configured to determine the acceleration of the touch display surface

Methodology Applied
Scientific EffectAcceleration: Accelerometer

Data Source

PatentEP4352592B1Acceleration sensor for touch display surfaces
Publication Date: 2025.11.12 HARMAN BECKER AUTOMOTIVE SYST GMBH
  • EP4352592B1 patent drawingFigure 1
  • EP4352592B1 patent drawingFigure 2
  • EP4352592B1 patent drawingFigure 3

AI summary

The invention relates to a sensor unit configured to determine an acceleration of a touch display surface, the sensor comprising: - a housing, - a contact element movably mounted along a first axis and configured to come into contact with the touch display surface, wherein the contact element is moved along the first axis when coming into contact with the touch display surface, - an acceleration sensor movably mounted in the housing at least along the first axis, - a biasing element located on one side of the acceleration sensor and configured to bias the acceleration sensor in one of the 2 directions along the first axis, wherein the contact element is movably mounted on the other side of the acceleration sensor opposite the biasing element and is coupled to the acceleration sensor to move the acceleration sensor against the bias of the biasing element in the other of the 2 directions along the first axis when contacting the touch display surface.