Robotic Work Tool Boundary Mapping Under Poor Signal Reception

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Robotic work tools, such as lawnmowers, face challenges in maintaining high accuracy and operation in areas with insufficient signal reception, leading to errors in boundary definition and navigation, especially when using satellite or beacon navigation systems.

Innovation Solution

The system employs a controller configured to determine boundary points and their variance, creating an inner envelope using intersections of tangents for variance circles, and utilizes optical navigation sensors with SLAM to record features and correct boundary inaccuracies, allowing the robotic work tool to operate accurately even in areas with poor signal reception.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Extent of automation

If satellite or beacon navigation systems are used to define boundaries, then the robotic work tool can operate autonomously in the work area, but navigation accuracy deteriorates in areas with insufficient signal reception

Engineering Contradiction:
Improveautonomous operationVSAvoidnavigation accuracy
Core Design Contradiction:
Extent of automationVSMeasurement precision

Solution Approach 1:

The patent introduces physical markers (intermediaries) placed at boundary locations to mediate between the satellite/beacon navigation system and the robotic work tool. These markers provide reference points that can be visually detected by the robotic tool, supplementing the signal-based navigation system and improving positioning accuracy in areas where satellite or beacon signals are insufficient.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent combines multiple navigation approaches: satellite navigation, beacon navigation, and visual marker recognition. By merging these different navigation methods, the system maintains autonomous operation while improving navigation accuracy across the entire work area, including areas with poor signal reception.

Inventive Principle:
Principle #5Merging (Combining)

2Measurement precision

If physical markers are placed along the boundary to define the work area, then navigation accuracy improves, but installation complexity and time increase

Engineering Contradiction:
Improveboundary definition accuracyVSAvoidinstallation complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent uses simple, inexpensive physical markers that can be easily placed and removed. These markers don't need to be permanent installations but serve as temporary reference points during boundary definition, reducing both cost and installation complexity while maintaining accuracy.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The system creates a digital copy or map of the physical boundary markers and work area. This digital representation allows the robotic tool to navigate using the captured boundary information without requiring continuous physical marker presence, simplifying installation while maintaining navigation accuracy.

Inventive Principle:
Principle #26Copying

3Device complexity

If the robotic work tool traverses the boundary to record positions, then the boundary can be defined virtually, but time consumption increases

Engineering Contradiction:
Improveboundary definition simplicityVSAvoidboundary definition time
Core Design Contradiction:
Device complexityVSLoss of time

Solution Approach 1:

The patent performs preliminary traversal and boundary recording during an initial setup phase. By completing the boundary definition work beforehand, the system establishes a virtual boundary map that enables rapid autonomous operation without repeated boundary traversal, reducing time consumption during actual work operations.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system continuously refines and updates the boundary information during initial traversal, capturing position data at multiple points along the boundary. This continuous data collection creates a more accurate virtual boundary representation, reducing the need for re-traversal and improving overall efficiency.

Inventive Principle:
Principle #20Continuity of useful action

Data Source

PatentEP4075229B1Improved installation for a robotic work tool
Publication Date: 2024.05.22 HUSQVARNA AB
  • EP4075229B1 patent drawingFigure 1A
  • EP4075229B1 patent drawingFigure 1B
  • EP4075229B1 patent drawingFigure 2A~2C

AI summary

A method for use in a robotic work tool system (300) comprising a robotic working tool (200), the robotic working tool (200) comprising a signal navigation device (290), wherein the method comprises: determining (515) a location of at least one boundary point (BP); determining (525) a variance of the location(s); and to determining the boundary (320) based on the variance of the location(s) utilizing the innermost of the variance(s).