Robotic Vacuum Sonar Waveguides for Dead Zone Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing SONAR systems for robotic vacuums face challenges in target resolution due to multipath interference and 'dead zones' caused by ground-plane reflections, leading to difficulties in navigating environments with multiple targets and varying floor types.

Innovation Solution

The implementation of a SONAR system with waveguides for emitters and receivers to direct signals effectively, minimizing Fresnel interference and optimizing transmitter-receiver spacing to improve target resolution and reduce 'dead zones', along with the use of various transducer types such as open-type PZT, closed-type PZT, and piezoelectret films to enhance signal clarity and robustness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If traditional SONAR systems are used without waveguides, then the system structure is simpler, but target resolution deteriorates and dead zones increase due to multipath interference

Engineering Contradiction:
Improvetarget resolutionVSAvoidsystem structure
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

Waveguides are introduced as intermediary structures between the transducers and the environment. These waveguides direct the acoustic signals along specific paths, preventing multipath interference by controlling signal propagation. The waveguides act as mediators that shape and direct the acoustic field, improving target resolution while managing the complexity through structured signal control.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Volume of moving object

If transducers are placed close to the ground plane, then the system occupies less vertical space, but dead zones increase due to ground-plane reflections

Engineering Contradiction:
Improvevertical space occupationVSAvoiddead zone reduction
Core Design Contradiction:
Volume of moving objectVSMeasurement precision

Solution Approach 1:

The system employs asymmetric waveguide designs with different flare angles for upward and downward directions. This asymmetry allows the waveguides to direct signals preferentially in desired directions while minimizing reflections from the ground plane. The asymmetric structure enables close placement to the ground while maintaining detection capability by controlling the acoustic field distribution.

Inventive Principle:
Principle #4Asymmetry

3Adaptability or versatility

If multiple transducers are used to improve coverage, then target detection capability improves, but the number of multipath interference paths increases

Engineering Contradiction:
Improveenvironmental coverageVSAvoidmultipath interference
Core Design Contradiction:
Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The system divides the acoustic field into distinct segments using multiple waveguides, each with specific directional characteristics. By segmenting the signal paths and assigning different waveguides to different spatial zones, the system achieves comprehensive environmental coverage while managing multipath interference through structured path separation. Each waveguide segment controls its own signal paths independently.

Inventive Principle:
Principle #1Segmentation

4Speed

If waveguides with large flare angles are used, then signal directionality improves, but the waveguide length and system complexity increase

Engineering Contradiction:
Improvesignal directionalityVSAvoidwaveguide length
Core Design Contradiction:
SpeedVSLength of stationary object

Solution Approach 1:

The waveguides are designed with moderate flare angles that provide sufficient directionality without requiring excessive length. Rather than using very large flare angles that would create long waveguides, the system employs optimized moderate angles that achieve adequate signal directionality in a compact form factor. This partial action approach balances directionality requirements with space constraints.

Inventive Principle:
Principle #16Partial or excessive action

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 solution enhances target resolution and reduces 'dead zones' in SONAR systems, allowing for more accurate navigation and obstacle detection in complex environments, while also providing the ability to determine floor types and minimize multipath interference.

Implementation Method 1

SONAR emitters and receivers thereon. The SONAR system comprises a waveguide or horn provided for each of the emitters and receivers

Methodology Applied
Scientific EffectAcoustic wave propagation: Sound

Implementation Method 2

the use of various transducer types such as open-type PZT, closed-type PZT, and piezoelectret films

Methodology Applied
Scientific EffectPiezoelectric effect: Piezoelectric Effect

Data Source

PatentEP2753954B1Sonar system for an autonomous vehicle
Publication Date: 2018.08.08 IROBOT CORP
  • EP2753954B1 patent drawingFigure 1
  • EP2753954B1 patent drawingFigure 2
  • EP2753954B1 patent drawingFigure 3

AI summary

A SONAR system for use with a robotic vacuum having SONAR emitters and receivers thereon. The SONAR system comprises a waveguide or horn located in front of the emitters and receivers that can improve the overall target resolution and reduce the number of "dead zones" where targets are not easily resolved.