Crane Unused Hook Vibration Control via Resonance Filtering

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cranes face challenges in reducing vibrations of unused hooks during load transportation, which can lead to contact with wire ropes or booms, affecting transportation efficiency and safety.

Innovation Solution

A crane system equipped with a hook detection unit, resonance frequency calculation, and a filter unit that generates a control signal to attenuate vibrations of unused hooks using notch filters, thereby reducing resonance frequency components and minimizing vibrations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the crane transports a load using the boom and wire rope, then the load can be moved to the desired position, but the unused hook vibrates due to resonance frequency, causing it to contact with the wire rope or boom

Engineering Contradiction:
Improvetransportation efficiencyVSAvoidvibration of unused hook
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The control device calculates the resonance frequency of the unused hook in advance and generates a filter control signal by removing the resonance frequency component before the vibration occurs. This preliminary filtering action prevents the harmful vibration from developing during load transportation.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The invention converts the harmful resonance vibration into a controllable parameter by calculating the resonance frequency and using it to design the filter control signal. By understanding and utilizing the resonance characteristics, the system eliminates the harmful effect rather than simply suppressing it.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

2Stability of the object's composition

If the operator performs manual operation to cancel the vibration of the load, then the load can be stabilized at the predetermined position, but the transportation efficiency is reduced due to the complexity of the operation

Engineering Contradiction:
Improvestability of load positionVSAvoidtransportation efficiency
Core Design Contradiction:
Stability of the object's compositionVSProductivity

Solution Approach 1:

The control device automatically detects the resonance frequency of the unused hook and adjusts the control signal accordingly. This closed-loop feedback mechanism eliminates the need for manual operator intervention while maintaining load stability, thereby improving transportation efficiency.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The crane system performs self-regulation by automatically calculating the resonance frequency and generating the appropriate filter control signal without requiring external operator input. This automation stabilizes the load position while maintaining high transportation efficiency.

Inventive Principle:
Principle #25Self-service

3Adaptability or versatility

If the crane uses multiple hooks for different operations, then the versatility is improved, but the unused hook causes vibration and potential contact with structural components

Engineering Contradiction:
Improvemulti-hook functionalityVSAvoidvibration from unused hook
Core Design Contradiction:
Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The control device identifies which hook is unused in advance and calculates its resonance frequency before transportation begins. The filter control signal is prepared beforehand to specifically target and eliminate the vibration of the identified unused hook, allowing multiple hooks to coexist without interference.

Inventive Principle:
Principle #10Preliminary 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 system effectively reduces vibrations of unused hooks, preventing contact with wire ropes or booms and enhancing transportation stability and efficiency.

Implementation Method 1

a calculation unit that calculates a resonance frequency for the wire rope suspending the detected unused hook among the plurality of wire ropes

Methodology Applied
Scientific EffectResonance: Resonance

Implementation Method 2

a filter unit that generates a filter based on the resonance frequency, and generates a second control signal by filtering the first control signal using the filter

Methodology Applied
Scientific EffectNotch filter: Filter (electronic)

Data Source

PatentEP3766822B1crane
Publication Date: 2024.11.20 TADANO LTD
  • EP3766822B1 patent drawingFigure 1
  • EP3766822B1 patent drawingFigure 2
  • EP3766822B1 patent drawingFigure 3~4

AI summary

This crane is provided with: a operable function unit which at least includes a boom; an operation unit which receives an operation input for operating the operable function unit; an actuator which drives the operable function unit; a generation unit which generates a first control signal for the actuator on the basis of the operation input; a plurality of wire ropes; a plurality of hooks suspended from a leading end section of the boom by the plurality of wire ropes, respectively; a hook detection unit which detects, from among the plurality of hooks, an unused hook suspending no load; a calculation unit which calculates a resonance frequency for a wire rope, among the plurality of wire ropes, that suspends the detected unused hook; a filter unit which generates a filter on the basis of the resonance frequency and generates a second control signal by filtering the first control signal using the filter; and a control unit which controls the actuator on the basis of the second control signal.