Theoretical And Experimental Research On Tuber Electrical Resistance Tomography Technology

Electrical Resistance Tomography(ERT)is an important branch of Electrical Tomography.It is being widely applied in many different fields including petroleum,chemical industry and geological exploration,due to its outstanding advantages like fast,non-disturbance,non-radiation and high performance-price ratio.In this paper,the application of ERT technology has been expanded to the field of agriculture,and the concept of TERT(Tuber Electrical Resistance Tomography)is proposed.The aim of TERT is to monitor the growth state and positional information of plant tuber in a non-radiation and visual way.It also provides a visual detection means and tool for new breed cultivation and Electronic Agriculture.In this paper,the theory and experiment of multi-tuber electrical resistance tomography have been studied.Firstly,a multi-tuber physical field model based on COMSOL Multiphysics was established,and the TERT positive problem of multi-tuber was simulated and studied.Secondly,the image reconstruction algorithm is designed and modified for multi-tuber resistance imaging.Finally,an experimental study was carried out on the TERT-Ⅰ prototype set up by the research group,and the multi-tuber resistance imaging system was established and improved.The main work of this paper includes:(1)The study of the positive problem of multi-tuber electrical resistance tomography.A multi-tuber physical field model was established and analyzed when the field was empty or there were tubers of different numbers,different positions,and different shapes.The corresponding regularities were summarized to lay the foundation for the reconstruction of multi-tuber images.(2)The study of multi-tuber image reconstruction algorithm.The LBP and MNR were introduced into the TERT system,and the imaging results were compared when there were multi-tuber in the field,and the regularity characteristics were summarized.(3)The Images reconstructed by image reconstruction algorithm were reprocessed.More clear soil/tuber distribution images of multiphase medium were obtained after the process of image binarization,mathematical morphology processing and edge extraction.(4)Based on the system analysis of data acquisition feasibility of TERT-Ⅰ prototype,the water medium and the insulating nylon rods were used to replace the soil and tuber respectively to carry on simulation experiments and concrete analysis in order to verify the feasibility and reliability of the multi-tuber image reconstruction algorithm.(5)The real experiment of saturated soil medium and potato tuber was carried out based on the TERT-Ⅰ prototype to verify the reconstruction algorithm of multi-tuber image and the method of data processing.The imaging situation was analyzed when there were tubers of different numbers,different positions,and different shapes in the field in order to verify the feasibility and reliability of multi-tuber imaging.