# A Novel Eddy Current Testing Error Compensation Technique Based on Mamdani-Type Fuzzy Coupled Differential and Absolute Probes

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## Abstract

**:**

## 1. Introduction

## 2. Related Work

#### 2.1. Lift-Off in ECT

_{a}, y

_{a}) and rotated by an angle. The transformation of p into x’, y’ is given by

#### 2.2. Air-Coils for ECT Measuring Lift-Off

#### 2.3. Mamdani-Type Fuzzy vs. Sugeno-Type Fuzzy

## 3. Methodology

#### 3.1. Architecture of the Proposed Error Compensation Eddy Current Testing (ECECT) System

#### 3.2. Proposed Probe Design

#### 3.3. Proposed Mamdani Fuzzy Logic Method in ECT Measurement

#### 3.3.1. Rules of Fuzzy Logic

#### 3.3.2. Surface Viewer for Fuzzy Logic

## 4. Experimental Setup

## 5. Experiments and Results

#### 5.1. Industrial Probe Measurement Result

#### 5.2. Hybrid Differential and Absolute Probe

#### 5.3. Hybrid Differential/Absolute Probe with Fuzzy Logic

#### 5.4. ANOVA Analysis Result

_{1}= +0.32833 − 0.089417 × (X

_{1}+ 0.74817) × (X

_{2}+ 0.34180) × X

_{3}

_{1}: Output Peak; X

_{1}: Frequency; X

_{2}: Depth Defect; X

_{3}: Coating Thickness.

## 6. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 3.**The views of Eddy Current Probe: (

**a**) Front View; (

**b**) Top View; (

**c**) Side View; (

**d**) Bottom View.

**Figure 4.**The Simulink Block Diagram Model for ECECT. (1) Input source, (2) Conditioning process, (3) Fuzzy logic process and feedback, (4) Output display.

**Figure 7.**Designing of ECECT Drive Circuit.1: AC signal; 2: Absolute Probe; 3: Buzzer; 4: Differential Probe; 5: ATMEGA 2560 microcontroller; 6: LCD Display; 7: Computer.

**Figure 8.**SFECT System Components Setup. 1: Computer; 2: ATMEGA 2560 microcontroller; 3: Absolute and Differential probe combining; 4: LCD display; 5: Function generator; 6: Calibration block.

Author | Technique Software or Hardware | Sensor Type | Research Area |
---|---|---|---|

[30] | Time domain analysis and frequency domain analysis based on differential responses | Pick-up coil is located orthogonally in the center at the bottom of the excitation coil | Reducing the lift-off problem and classify the defects. |

[12] | Measuring the defect dimension based on the slope of the linear curve of the peak value | Hall sensor | Reducing the lift-off noise for detection of the defect depth or width |

[31] | Hough transform was used | Coil | Investigating the lift-off effect in the normalized impedance plane |

[32] | The theory of the linear transformer | GMR | Measuring the thickness of a metallic non-ferromagnetic plate |

[33] | Normalisation technique | Coil | Minimise lift-off impact. It could be utilized to measure metal thickness and for microstructure analysis. |

[34] | Analytical model that describes the inductance | Air-cored coil | The sensor phase signature analysis reveals that liftoff is independent for the testing plate. |

[35] | Introducing a novel Permeability measurement approach | Coil | Investigating the phenomenon of conductivity invariance with a controlled lift-off for magnetic plates. |

Rules | Differential Probe | Absolute Probe | Depth of Defect |
---|---|---|---|

1 | lowdefect | Lowliftoff | normaldefect |

2 | depthdefect | Lowliftoff | dangedefec |

3 | depthdefect | mediumliftoff | baddefect |

4 | depthdefect | highliftoff | baddefect |

5 | dangerdefect | lowliftoff | dangerdefect |

6 | dangerdefect | mediumliftoff | dangerdefect |

7 | dangerdefect | highliftoff | baddefect |

8 | lowdefect | mediumliftoff | baddefect |

9 | lowdefect | highliftoff | baddefect |

Frequency (kHz) | Differential Probe (%) | Absolute Probe (%) | |||||
---|---|---|---|---|---|---|---|

1 mm | 2 mm | 3 mm | 0.5 mm | 1 mm | 1.5 mm | 2 mm | |

4 | 2 | 5 | 10 | 20 | 10 | 5 | 2 |

10 | 10 | 20 | 25 | 65 | 40 | 20 | 5 |

20 | 20 | 60 | 80 | 100 | 65 | 45 | 15 |

Liftoff (mm) | Error from (Yin & Xu, 2016) (%) | Error from ECECT (%) |
---|---|---|

zero | 0.23 | 0.10 |

1.5 | 0.64 | 0.50 |

3 | 1.36 | 0.40 |

4.5 | 1.63 | 0.87 |

Source | Sum of Squares | df | Mean Square | F Value | p-Value Prob > F |
---|---|---|---|---|---|

Model | 78.81 | 3 | 26.27 | 146.08 | <0.0001 |

A-Frequency | 2.88 | 1 | 2.88 | 16.01 | 0.0002 |

B-Depth Defect | 67.17 | 1 | 67.17 | 373.51 | <0.0001 |

C-Coating Thickness | 8.76 | 1 | 8.76 | 48.72 | <0.0001 |

Residual | 10.07 | 56 | 0.18 | ||

Cor Total | 88.88 | 59 |

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**MDPI and ACS Style**

Abdalla, A.N.; Ali, K.; Paw, J.K.S.; Rifai, D.; Faraj, M.A.
A Novel Eddy Current Testing Error Compensation Technique Based on Mamdani-Type Fuzzy Coupled Differential and Absolute Probes. *Sensors* **2018**, *18*, 2108.
https://doi.org/10.3390/s18072108

**AMA Style**

Abdalla AN, Ali K, Paw JKS, Rifai D, Faraj MA.
A Novel Eddy Current Testing Error Compensation Technique Based on Mamdani-Type Fuzzy Coupled Differential and Absolute Probes. *Sensors*. 2018; 18(7):2108.
https://doi.org/10.3390/s18072108

**Chicago/Turabian Style**

Abdalla, Ahmed N., Kharudin Ali, Johnny K. S. Paw, Damhuji Rifai, and Moneer A. Faraj.
2018. "A Novel Eddy Current Testing Error Compensation Technique Based on Mamdani-Type Fuzzy Coupled Differential and Absolute Probes" *Sensors* 18, no. 7: 2108.
https://doi.org/10.3390/s18072108