Optical Force Sensor Arrangement With Deformable Reflective Surface

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing sensor arrangements for robotic applications lack sufficient resolution and are fragile, making them inadequate for precise force sensing and manipulation.

Innovation Solution

A sensor arrangement with an elastically deformable wall and a light source and image sensor configuration that uses optical image recognition to infer forces through a sensitive light pattern, featuring a base portion, a top portion with a reflective surface, and a light source arrangement to emit structured light.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If traditional sensor arrangements are used for force sensing in robotic applications, then the device structure is simple, but the measurement precision and resolution are insufficient

Engineering Contradiction:

Improveforce sensing resolutionVSAvoidsensor arrangement structure

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces traditional mechanical force sensors with an optical measurement system. Light sources project structured light patterns onto the measurement surface, and image sensors capture the reflected light. When forces are applied to the measurement surface, the surface deforms elastically, causing corresponding deformations in the reflected light pattern. This optical approach achieves high-resolution force sensing without the mechanical complexity and fragility of traditional force sensors.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent utilizes the elastic deformation parameter of the measurement surface as an intermediate parameter for force measurement. Instead of directly measuring force with mechanical sensors, the system measures the dimensional changes (deformation) of the measurement surface under applied forces. The light pattern deformation directly reflects the surface deformation, providing high-resolution force information through optical parameter changes rather than mechanical parameter changes.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If traditional force sensors are used, then the device structure is simple, but the reliability and fragility are poor

Engineering Contradiction:

Improvesensor durabilityVSAvoidoptical system structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces fragile mechanical force sensors with a robust optical system. The measurement surface itself becomes the sensing element, eliminating the need for separate mechanical sensors that are prone to failure. The optical components (light sources and image sensors) are positioned to view the measurement surface, creating a reliable system where the measurement surface's elastic deformation is directly observed through light reflection, significantly improving durability while maintaining simplicity.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Measurement precision

If the measurement surface is made more sensitive to force, then the measurement precision improves, but the device becomes more fragile

Engineering Contradiction:

Improveforce detection sensitivityVSAvoidmeasurement surface durability

Core Design Contradiction:

Measurement precisionVSStrength

Solution Approach 1:

The patent changes the material parameter of the measurement surface to an elastic material that can undergo reversible deformation. This elastic measurement surface is designed to deform in response to applied forces within its elastic limit, allowing repeated measurements without permanent deformation or damage. The light pattern deformation accurately reflects these elastic deformations, providing high sensitivity while maintaining the strength and durability of the measurement surface.

Inventive Principle:

Principle #35Parameter changes

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 sensor arrangement provides high-resolution, sensitive force inference capable of detecting force direction and shape, with a force map comprising multiple force vectors, enabling accurate robotic manipulation.

Implementation Method 1

Light reflected at the reflective surface yields a pattern on the image sensor that depends on forces applied on the measurement surface

Methodology Applied

Scientific EffectReflection: Reflection

Implementation Method 2

a top portion comprising an elastically deformable wall, the top portion being mounted on the base portion such that the top portion and the base portion define an interior space

Methodology Applied

Scientific EffectElasticity: Elasticity

Data Source

PatentUS12578242B2Sensor arrangement for sensing forces and methods for fabricating a sensor arrangement and parts thereof

Publication Date: 2026.03.17 MAX PLANCK GESELLSCHAFT ZUR FOERDERUNG DER WISSENSCHAFTEN EV

AI summary

The disclosure relates to a sensor arrangement for sensing forces, including a measurement surface and optical detection of reflected light. The disclosure relates further to corresponding fabrication methods.