Excavator Bucket Control With Entry-Prohibited Surface Limits

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing working machines face issues where the leading end attachment, such as a bucket, may deviate from its intended action due to pressure confinement, structural rattling, or swaying, leading to excessive excavation beyond the target work surface.

Innovation Solution

A working machine with a controller that includes an operation control part for semi-automatic operation and an operation restriction part to prevent the attachment from exceeding a set entry prohibited surface, ensuring the bucket maintains proximity to the target work surface by restricting its movement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If semi-automatic control is executed to make the work surface come closer to the target work surface, then excavation precision is improved, but the attachment may unintentionally advance beyond the target work surface due to pressure confinement, structural rattling, or swaying

Engineering Contradiction:
Improveexcavation precisionVSAvoidattachment position control reliability
Core Design Contradiction:
Manufacturing precisionVSReliability

Solution Approach 1:

The system performs preliminary actions by setting an entry prohibited surface at a position spaced from the target work surface before the attachment reaches it. The operation restriction part is activated in advance to prevent the leading end attachment from approaching beyond this pre-set boundary, thereby avoiding excessive excavation before it occurs.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The entry prohibited surface acts as an intermediary boundary between the work surface and the target work surface. The operation restriction part uses this intermediate boundary to control the attachment's movement, preventing direct contact with the target work surface while still allowing precise excavation work to be performed.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of operation

If the attachment is allowed to move freely to perform work, then operational flexibility is improved, but the leading end attachment may excessively excavate beyond the target work surface

Engineering Contradiction:
Improveattachment operation flexibilityVSAvoidwork surface precision
Core Design Contradiction:
Ease of operationVSManufacturing precision

Solution Approach 1:

The system dynamically adjusts the operation restriction based on the attachment's position. The operation restriction part monitors the position of the leading end attachment and applies restrictions only when necessary to prevent exceeding the entry prohibited surface, while allowing free movement within safe boundaries. This dynamic approach maintains operational flexibility while ensuring precision.

Inventive Principle:
Principle #15Dynamics

3Manufacturing precision

If operation restrictions are imposed to prevent excessive excavation, then excavation precision is improved, but the complexity of the control system increases

Engineering Contradiction:
Improveexcavation precisionVSAvoidcontrol system complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The control system is segmented into distinct functional parts: the operation control part for semi-automatic control, the operation restriction part for boundary enforcement, and the manipulation part for user input. This segmentation allows each part to perform its specific function independently, making the overall system more manageable and easier to implement despite the added complexity.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP4692462A1Work machine
Publication Date: 2026.02.11 KOBELCO CONSTR MASCH CO LTD
  • EP4692462A1 patent drawingFigure 1
  • EP4692462A1 patent drawingFigure 2
  • EP4692462A1 patent drawingFigure 3

AI summary

Provided is a working machine (1) that achieves prevention of excessive excavation by a leading end attachment to a position deeper than a target work surface. The working machine (1) includes an operation control part and an operation restriction part. The operation restriction part executes an operation control of controlling an operation of an attachment (30) so that a work surface (73) comes closer to a target work surface (71) set in advance when a manipulation part receives a control instruction manipulation given thereto. The operation restriction part restricts, under no execution of the operation control, the operation of the attachment (30) to prevent a bucket (33) from approaching the target work surface (71) beyond an entry prohibited surface (72) set at a position spaced from the target work surface (71) in an opposite direction to a direction in which the work surface (73) comes closer the target work surface (71).