Ultrasonic Sensor Layout for Precise Obstacle Avoidance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Self-moving devices face challenges in accurately recognizing obstacles and responding appropriately to avoid collisions, which compromises their safety and efficiency.

Innovation Solution

The implementation of a self-moving device with at least two non-contact obstacle detection modules, positioned on either side of the housing, that transmit and receive detection signals in a time-sharing manner to determine the location of obstacles, allowing the device to adjust its movement and avoid obstacles effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If contact-based obstacle detection is used, then the device can detect obstacles, but it causes collision and safety issues

Engineering Contradiction:
ImprovesafetyVSAvoidcollision
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent replaces mechanical contact-based obstacle detection with non-contact ultrasonic wave detection. The ultrasonic sensor emits sound waves that reflect off obstacles and return to the sensor, allowing the device to detect obstacles without physical contact, thereby eliminating collision hazards while maintaining detection capability

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

2Measurement precision

If multiple ultrasonic sensors are arranged with parallel axes, then the detection coverage is simplified, but the obstacle location recognition precision is reduced

Engineering Contradiction:
Improveobstacle location recognition precisionVSAvoidsensor arrangement complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent employs asymmetric arrangement of ultrasonic sensors with intersecting axes rather than parallel alignment. By positioning the sensors such that their detection axes intersect at a point in front of the device, the system creates overlapping detection zones that enable precise triangulation of obstacle locations, improving measurement precision through geometric asymmetry

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

The patent transitions from one-dimensional parallel sensor alignment to two-dimensional intersecting sensor arrangement. The intersecting axes create a spatial geometry where detection zones overlap in a manner that provides both azimuth and distance information, adding dimensional complexity to the sensor layout while significantly enhancing location recognition precision

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Measurement precision

If ultrasonic sensors are used for obstacle detection, then non-contact detection is achieved, but the obstacle location recognition precision is insufficient

Engineering Contradiction:
Improveobstacle location recognition precisionVSAvoidobstacle detection capability
Core Design Contradiction:
Measurement precisionVSDifficulty of detecting and measuring

Solution Approach 1:

The patent introduces the intersection point of ultrasonic wave axes as a virtual intermediary reference point. By calculating obstacle positions relative to this intersection point using time-of-flight measurements from multiple sensors with intersecting axes, the system achieves precise location recognition. The intersecting geometry creates a natural reference framework that simplifies the mathematical calculation of obstacle positions while maintaining non-contact detection

Inventive Principle:
Principle #24Intermediary (Mediator)

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

This solution enables the self-moving device to accurately recognize obstacles without collision, enhancing safety, improving operational efficiency, and providing a more intelligent and user-friendly experience by ensuring continuous movement and smoother operation.

Implementation Method 1

configured to transmit detection signals and receive reflected detection signals, to detect an obstacle in the moving direction of the self-moving device

Methodology Applied
Scientific EffectUltrasonic reflection: Reflection

Data Source

PatentEP3920002B1Self-moving device and associated obstacle detection method
Publication Date: 2023.12.27 POSITEC POWER TOOLS (SUZHOU) CO LTD
  • EP3920002B1 patent drawingFigure 1
  • EP3920002B1 patent drawingFigure 2
  • EP3920002B1 patent drawingFigure 3(a)

AI summary

The present invention relates to a self-moving device, where the self-moving device includes at least two non-contact obstacle detection modules, respectively located on two side of a housing in a moving direction and configured to transmit detection signals and receive reflected detection signals, to detect an obstacle in the moving direction of the self-moving device; the self-moving device further includes a control module, and the control module turns on each obstacle detection module in a time-sharing manner to transmit the detection signal and turns on each obstacle detection module in the time-sharing manner to receive the reflected detection signal, to obtain detection data; and the control module determines a location of the obstacle according to the obtained detection data, a corresponding identity of the obstacle detection module that transmits the detection signal, and a corresponding identity of the obstacle detection module that receives the detection signal, to control the self-moving device to move and/or turn to avoid the obstacle, and the identities of the obstacle detection modules are related to positions of the obstacle detection modules relative to the housing.