Crane Hook IMU Detects Plumb Deviation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing crane systems face challenges in accurately detecting unsafe, out-of-plumb conditions of lifting hooks, especially when the crane boom is long, elevated, or subject to wind, leading to potential equipment damage and injury.

Innovation Solution

A sensing device equipped with an inertial measurement unit (IMU) that includes a gyroscope, accelerometer, and magnetometer, which measures the pitch and yaw of the crane hook relative to a plumb position and activates an alert if the deviation exceeds a predetermined limit.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If visual identification by experienced crane operators is used to detect overloaded crane boom, then operator expertise can be utilized, but accuracy deteriorates when boom is long, elevated, or subject to wind

Engineering Contradiction:
Improvevisual identification capabilityVSAvoiddetection accuracy of out-of-plumb condition
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The patent replaces the mechanical/visual inspection method with an electronic sensing system. An inertial measurement unit (IMU) with accelerometer, gyroscope, and magnetometer is mounted on the hook to automatically detect and measure hook orientation and out-of-plumb conditions, eliminating reliance on human visual judgment and providing precise quantitative measurements even in difficult conditions.

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

Solution Approach 2:

The patent introduces an intermediary sensing device between the hook and the operator. The IMU unit acts as a mediator that directly measures hook orientation and communicates out-of-plumb conditions to the operator through visual or audible alerts, bridging the gap between the physical hook position and human perception.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If third party instructions are relied upon for out-of-view loads, then operator safety is maintained, but response time and accuracy deteriorate

Engineering Contradiction:
Improvesafety of out-of-view operationsVSAvoidresponse time for detecting unsafe conditions
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The sensing device enables the hook system to monitor and report its own status automatically. The IMU unit continuously tracks hook orientation and independently generates alerts when out-of-plumb conditions are detected, eliminating the need for third-party riggers to visually monitor and communicate load position, thereby reducing response time and improving safety.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent implements a feedback mechanism where the IMU sensor continuously monitors hook position and provides real-time information back to the operator through visual or audible alerts. This closed-loop feedback system enables immediate detection and response to unsafe conditions without relying on external observers.

Inventive Principle:
Principle #23Feedback

3Device complexity

If simple alert systems are used for hook deviation, then system complexity is reduced, but measurement precision and reliability deteriorate

Engineering Contradiction:
Improvesensing system structureVSAvoidhook deviation detection accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent combines multiple sensing technologies (accelerometer, gyroscope, magnetometer) into a single integrated IMU unit mounted on the hook. This merging of three separate sensors into one compact device provides comprehensive orientation measurement (pitch, roll, and yaw) while maintaining relatively simple system architecture and enabling precise detection of hook deviation from plumb position.

Inventive Principle:
Principle #5Merging (Combining)

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 sensing device effectively detects deviations from the plumb position, providing real-time alerts to operators and riggers, thereby enhancing safety and preventing accidents by ensuring proper alignment of the crane hook during lifting operations.

Implementation Method 1

The inertial measurement unit comprises an electronic gyroscope adapted to measure orientation of the hook and obtain orientation data

Methodology Applied
Scientific EffectGyroscope: Gyroscope

Implementation Method 2

The inertial measurement unit further comprises an accelerometer adapted to measure orientation of the hook and obtain orientation data

Methodology Applied
Scientific EffectAccelerometer: Accelerometer

Implementation Method 3

The inertial measurement unit comprises a magnetometer adapted to measure changes of the hook relative to magnetic north

Methodology Applied
Scientific EffectMagnetometer: Magnetometer

Data Source

PatentEP3787993B1Sensing device for a crane
Publication Date: 2025.05.28 BEDGOOD THOMAS
  • EP3787993B1 patent drawingFigure 1
  • EP3787993B1 patent drawingFigure 2
  • EP3787993B1 patent drawingFigure 3

AI summary

A sensing device for a crane for detecting unsafe operating conditions including an inertial measurement unit for measuring pitch and yaw of a hook of a crane attached to a load. The inertial measurement unit is adapted to measure deviation of the hook of the crane from a plumb position and activate an alert element if the deviation of the hook exceeds a predetermined limit.