Thesis: Signal processing and development of ultrasonic defect reconstructi

The research institute Swerim provides applied research within mining engineering, process metallurgy and materials and manufacturing engineering, mainly for the mining, steel and metals industry. Swerim has 190 co-workers in two locations in Sweden - Luleå and Stockholm.

The thesis work will consist of a literature study, analysis of ultrasonic data, develop a code for volume reconstruction from ultrasonic data. The analysis will be performed in the Matlab environment.

The results will be in the form of a technical report and an oral presentation.

Performing thesis work at Swerim will give you the experience of working as a researcher in a stimulating environment with modern laboratories, in a team with skilled researchers developing tomorrow’s technologies for industry. You will have the possibility to meet and connect with industrial partners and to understand their needs and interest. Swerim rewards the student with 50 000 SEK for an approved master thesis (30hp).

Goal
Develop a general/generic code with GUI for 3D volume reconstruction from ultrasonic data. This will be carried out by both theoretical and experimental analysis

Background
Ultrasonic testing (UT) is non-destructive method for evaluation of material properties and defect characterization in the metal industry. There are several different UT-techniques that is used at Swerim, such as Laser ultrasound, EMAT and immersion UT. By performing a number of point measurements in a 2D plane, from which the data can be summed together from the reflected ultrasonic waves into a 3D representation. Synthetic aperture focusing technique (SAFT) is a way to increase the signal-to-noise ratio (SNR) from defect indications

Thesis description
1. Literature study on SAFT techniques and methods for defect size determination and volume reconstruction.
2. Signal processing using Matlab of data acquired from ultrasonic measurements.
4. Develop a Matlab class (built upon already existing) and GUI for volume reconstruction using SAFT.
5. Report and examination.

We are looking for you that are at the end your Master of Science studies, preferably in Programming/Computer science/ Engineering physics. Strong interest in signal processing, developing software and coding is an advantage. We want you to be able to take own initiatives, be comfortable with addressing challenging problems, and have good communications skills in both written and spoken English.

Location and time
The thesis work will be performed at Swerim in Kista with a proposed start in early 2021.

Contact
Mikael Malmström, Senior Researcher, Mikael.Malmstrom@swerim.se, +46 (0)70 226 38 88