Hybrid Tomograph

From 01.11.2015, Netrix S.A. realizes the project co-financed by the European Regional Development Fund – ” Hybrid Tomograph for inspection wall moisture and building condition.

Project description

The project assumes the creation of a tomographic system (measuring device and software for interpretation of measurement results) using both impedance tomography and capacitive tomography for the spatial analysis of the degree of moisture in the walls. In addition, the prototype device by using two tomographic techniques will allow analysis of the plate state with particular attention to the blocks of the so-called large plate (test fixation and reinforcement state in concrete walls). The ECIT (Electrical Capacitance and Impedance Tomograph) prototype will allow simultaneous measurement of capacitance and impedance with active surface electrodes. The Hybrid Tomograph will be a modular, compact, configurable device that allows you to work in a variety of measurement systems.

The basic element of the system will be an active measuring electrode containing analog keys and ADC and CDC converters. The active electrodes will be connected to a digital module that performs reading and data transmission to the control module. The control module will provide device configuration, implementation of the measurement cycle, pre-processing measurement data and communication with the computer system, data acquisition and visualization. Tomograph will eventually operate a probe containing 32 active electrodes. The last part of the system is software for image reconstruction. The planned solution will be based on the latest scientific achievements in image reconstruction.

The project will develop and apply new procedures and algorithms in the field of theoretical computer and numerical mathematics. Using neural network, genetic algorithms, approximation theory, topological methods, hybrid algorithms, fuzzy sets, and gradient methods. The developed algorithms will develop methods and concepts in the field of reconstruction and analysis of images and the appropriate form of their presentation.

Purpose of the project

Purpose of the project is to create a hybrid tomographic measuring system (measuring device and software for interpretation of measurement results) using both impedance tomography and capacitive tomography. The tomographic system to be developed as a result of this project will be a novel and innovative solution in the study of dampness and condition determination of buildings, both in terms of the measuring device itself and with the implemented algorithms.

The use of modern tomography techniques as well as intelligent algorithms (eg neural networks) will allow non-invasive and very accurate spatial determinants of humidity. Electrical Tomography is a range of tomography techniques that describe the electrical parameters of an object placed in a measurement space under different names. In the case of electrical capacitance tomography (ECT), this will be an imaging of electrical permeability ε, in the case of impedance tomography (EIT – Electrical Impedance Tomography) is a technique of spatial imaging of conductivity σ. In the above-mentioned types of tomography, there is a generation of electric field due to current excitation (EIT) or voltage (ECT). Due to the other way of acting (excitation), EIT and ECT tomography have not been applied to simultaneous imaging of permeability and conductivity in a single probe.

Although there are many methods of testing brick wall humidity, there is currently no one universal method that can be used in different measuring conditions. Each method has its advantages, disadvantages and conditions that allow it to apply only in the circumstances. The main problem that is currently encountered in the wall moisture tests is the lack of a method to determine its spatial distribution without the need for sampling. The vast majority of available research methods allow to determine the humidity point, so it is possible to obtain only discrete distributions. In the case of indirect methods (thermal imaging camera) it is possible to determine the concentration of water only on the surface of the wall or in its subsurface zone. This is a major problem for thick walls, as the moisture inside the wall is usually a few percent higher than at the surface. The destructive nature of currently used methods requiring sampling, especially in historical objects, is unacceptable. In such cases, you should only use non-destructive methods. The proposed hybrid method, in which the moisture content of construction materials is determined indirectly by the determination of a different physical property (ε, σ), will cause the measurement to be repeated several times without damaging the object. At the same time, the distribution of moisture within the wall will be archived on an IT medium and compared with subsequent research results at any time. The method will, therefore, be very useful for the control and effectiveness of the anti-moisture protection, as well as the effectiveness of accelerated drying particularly thick walls.

Impedance tomography as well as capacitive tomography are relatively new imaging techniques and their development is dynamic. In recent years, they have been applied in various fields, from the refining industry, through the electronics industry to biomedical applications.

Computed tomography has been used in: medicine, eddy current defectoscopy, laminar and turbulent liquid flow detection and control, or in geophysics. The main advantages of the proposed hybrid tomographic system are: non-destructive and non-destructive testing of the object, the possibility of imaging small changes in both permeability and conductivity, as well as the low cost of the measuring device and its operation.

The superiority of the proposed hybrid tomographic system is also based on the application of new innovative procedures and algorithms in the field of theoretical computer and numerical mathematics. The implementation of copyright algorithms to solve the image reconstruction problem will improve the quality (resolution) of the image obtained. Targeted solutions will test and apply algorithms that use neural network, genetic algorithms, fuzzy sets theory, approximation, topological methods, and hybrid algorithms.

The value of the Project is 6 472 397,99 PLN

The contribution of the European Funds is 4 833 136,33 PLN