Flexible-Arm Boring Machine for Arbitrary Cross-Section Excavation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional rock tunnel boring machines are limited to excavating circular cross-sections, making them inflexible and inefficient for projects requiring diverse or changing cross-sectional shapes, leading to increased costs, resource wastage, and prolonged construction periods under complex geological conditions.

Innovation Solution

A robot-supported multi-cutterhead boring machine with a flexible-arm system, utilizing coupled torques of multiple cutterheads and an intelligent robot arm to adjust cutterhead positions and postures, enabling excavation of tunnels with any cross-sectional shape while reducing stress on key components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a conventional circular boring machine is used for excavation, then the structure is simple and reliable, but the excavation cross-section is limited to circular shape and cannot adapt to diverse cross-section requirements

Engineering Contradiction:
Improvecross-section adaptabilityVSAvoidboring machine structure
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The cutterhead is divided into multiple independent cutter units that can be individually positioned and controlled. Each cutter unit can be adjusted to different positions and angles, allowing the formation of various cross-sectional shapes including rectangular, horseshoe-shaped, and other customized sections, thereby resolving the contradiction between adaptability and structural simplicity

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The boring machine employs dynamic adjustment mechanisms that allow real-time modification of cutterhead configuration. The cutter units can be dynamically repositioned during operation to adapt to different excavation requirements, enabling the machine to transition between various cross-sectional shapes without requiring complete redesign, thus improving adaptability while maintaining operational simplicity

Inventive Principle:
Principle #15Dynamics

2Adaptability or versatility

If the excavation cross-section is determined early in the project, then the boring machine can be optimized for that specific shape, but it becomes difficult to change cross-section later and reduces flexibility for different project requirements

Engineering Contradiction:
Improvecross-section changeabilityVSAvoidconstruction efficiency
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The system enables dynamic reconfiguration of the cutterhead arrangement during excavation operations. Multiple cutter units can be independently adjusted to different positions and orientations, allowing the boring machine to switch between various cross-sectional shapes mid-project, thereby maintaining high productivity while achieving cross-section adaptability

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The boring machine allows continuous adjustment of geometric parameters such as cutter spacing, cutter angle, and cutter depth. By changing these parameters, the machine can transform the excavation cross-section from one shape to another without interrupting operations or requiring complete redesign, thus resolving the contradiction between changeability and productivity

Inventive Principle:
Principle #35Parameter changes

3Productivity

If a single cutterhead structure is used, then the device complexity is low, but the working efficiency is limited and large reactive torque is generated requiring increased component size and thickness

Engineering Contradiction:
Improveexcavation efficiencyVSAvoidcutterhead structure
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The single cutterhead is segmented into multiple independent cutter units, each capable of operating independently or in coordination. This segmentation allows for more efficient rock breaking and excavation by distributing the cutting action across multiple points, thereby improving productivity without requiring excessive increases in individual component size

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The multiple cutter units are arranged and controlled to generate counterbalancing reactive torques that offset each other. By coordinating the rotation directions and speeds of different cutter units, the system reduces the net reactive torque on the boring machine, allowing for more efficient operation without requiring oversized components to handle excessive torque loads

Inventive Principle:
Principle #8Anti-weight (Counterweight)

4Ease of manufacture

If the boring machine is designed for a specific cross-section, then the structure can be optimized for that shape, but it causes increased project cost when excavating diverse cross-sections due to extra excavation and backfilling requirements

Engineering Contradiction:
Improvecross-section formationVSAvoidmaterial and resource waste
Core Design Contradiction:
Ease of manufactureVSLoss of substance

Solution Approach 1:

The boring machine is designed with universal cutterhead configuration capabilities that can form multiple cross-sectional shapes including circular, rectangular, horseshoe-shaped, and customized sections. This multi-functionality allows a single machine to handle diverse project requirements without requiring extra excavation or backfilling operations, thereby reducing material waste and project costs while maintaining ease of cross-section formation

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentEP3872299B1Robot-supported flexible-arm boring machine capable of excavating tunnel with arbitrary cross section
Publication Date: 2023.10.25 CHINA RAILWAY ENGINEERING EQUIPMENT GROUP CO LTD
  • EP3872299B1 patent drawingFigure 1~2
  • EP3872299B1 patent drawingFigure 3~4
  • EP3872299B1 patent drawingFigure 5

AI summary

Disclosed is a robot (4)-supported flexible-arm boring machine capable of excavating a tunnel with any cross-section, comprising a cutterhead and cutter system (1) and a main beam (6). A rear portion of the main beam (6) is connected to a front portion of a rear gripper (8) by means of a thrust cylinder (7); a rear portion of the rear gripper (8) is connected to a rear support (9); and a front portion of the main beam (6) is flexibly connected to the cutterhead and cutter system (1) by means of a robot (4).