Optical 3-Axis Sensor Using Geometric Shape Projection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional multi-axis sensors, particularly two-axis systems like joysticks, face issues with durability and sensitivity, where they either fail under high forces or are unresponsive to low forces, and are difficult to clean and disinfect, especially in medical settings, due to mechanical wear and protective rubber components.

Innovation Solution

An optical, adaptive three-axis sensor system that projects a geometric shape onto an image sensor, allowing for real-time adjustment to desired input forces and movement ranges, using a projection unit connected to a force-absorbing element, which calculates X, Y, and Z coordinates based on distortion, enabling high-resolution output signals and easy cleaning.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If conventional mechanical sensor systems are designed to be robust for high forces, then durability is improved, but sensitivity to low forces deteriorates

Engineering Contradiction:
ImprovedurabilityVSAvoidsensitivity
Core Design Contradiction:
StrengthVSMeasurement precision

Solution Approach 1:

The patent replaces mechanical sensor systems with an optical system consisting of a projection unit, image sensor, and evaluation unit. This substitution eliminates mechanical wear and tear while maintaining the ability to detect forces across a wide range, from very low to very high forces, thereby resolving the contradiction between durability and sensitivity.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If protective rubber components are added to prevent ingress of foreign matter, then reliability is improved, but ease of cleaning deteriorates

Engineering Contradiction:
Improveprotection against foreign matterVSAvoidcleaning and disinfection
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

By replacing the mechanical sensor system with an optical system, the patent eliminates rubber bellows and protective rubbers that are difficult to clean. The optical components can be easily cleaned and disinfected, especially important for medical applications, while maintaining protection against foreign matter through the sealed design of the projection unit and image sensor.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Ease of manufacture

If mechanical sensor systems are used, then ease of manufacture is improved, but productivity deteriorates due to wear and tear

Engineering Contradiction:
ImprovemanufacturabilityVSAvoidoperational lifespan
Core Design Contradiction:
Ease of manufactureVSProductivity

Solution Approach 1:

The patent replaces mechanical sensing mechanisms with an optical system that has no moving parts subject to wear. The projection unit projects a geometric pattern onto a target, and the image sensor captures the pattern. This eliminates mechanical wear and tear entirely, significantly extending the operational lifespan while maintaining ease of manufacture through standardized optical components.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

4Measurement precision

If optical systems with light sensors are used, then measurement precision is improved, but device complexity increases

Engineering Contradiction:
Improveposition determination accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent uses a single image sensor to measure positions in three-dimensional space (X, Y, Z coordinates) by analyzing the distortion of a projected geometric pattern. This multi-functional approach allows the system to achieve high measurement precision while avoiding the complexity of multiple separate sensors or complex mechanical structures, as the evaluation unit processes the pattern distortion to extract all spatial information.

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

The system provides high accuracy, resistance to wear, and adaptability to varying user forces, ensuring reliable operation across different applications with improved cleaning and disinfection capabilities, and increased resolution through image analysis and interpolation.

Implementation Method 1

A light source (e.g. LED or laser) is assigned to the projection unit; for example includes the projection unit itself the light source

Methodology Applied
Scientific EffectLight projection: Light

Implementation Method 2

forces acting on the force absorption produce an inversely exponential deflection of the projected image on the image sensor

Methodology Applied
Scientific EffectForce absorption: Deformation

Data Source

PatentEP3345068A1Device and method for determining the position of a force-absorbing element in three axes
Publication Date: 2018.07.11 BUCHHOLD NIELS

AI summary

A device for determining the position of a force-absorbing element (2) in three axes comprises a high-resolution image sensor (6), a movement support (4) which is arranged opposite the image sensor and is connected to the force-absorbing element (2), a projection device (3) which is connected to the movement support (4) and projects, onto the image sensor, a predefined geometric shape (10) which is positioned and distorted according to an x/y/z inclination of the movement support. A computing device (7) derives, from the position and distortion of the geometric shape (10), high-resolution x/y/z coordinates for further processing.