Research On Key Technologies Of Automatic Inspection For Building Facilities Based On Tracked Mobile Robot

With the process of urbanization,functional building facilities such as tunnels,pipe galleries and warehouses have become the basic components of modern cities.Due to fundamentality and inclusiveness of these building facilities,it may cause huge inconvenience of daily life in modern cities once an accident happened for flaws in structures.Therefore,it is vital to monitor the structure and equipments of building facilities all day and seamlessly.A monitoring system with mobile inspection has been formed.Automatic inspection technology based on mobile robots has been developed which effectively solves the challenges brought by the wide distribution of building facilities,the complex internal structure,the diversity of defects and lesions and the harsh working environment.However,the current automatic inspection technology based on mobile robot still faces some problems such as lack in robot crawling ability,autonomous navigation and visual detection of defects which should be solved.Based on the above background,research on key technologies of automatic inspection for building facilities based on tracked mobile robot is proposed.On the basis of understanding the current situation and development trend of related technologies at home and abroad,the scheme of automatic inspection technology for building facilities based on tracked mobile robot is brought forward.General planning of system and mechanical design of the tracked mobile robot are completed.Key technologies which include motion control,autonomous navigation and positioning of tracked robot and visual detection of structure and lesions in building facilities are focused.Meanwhile,the system of automatic inspection technology for building facilities based on tracked mobile robot are developed.Related experiments are carried out to verify the feasibility and effectiveness of the methods developed in this paper.This paper presents the following contributions:In Chapter 1,the significance of comprehensive building facilities and automatic inspection is discussed.The current situation and development trend of automatic inspection technology for building facilities at home and abroad are summarized.The problems and corresponding countermeasures with automatic inspection technology for building facilities based on robot and research directions of the paper are analyzed.The research content and chapters of the paper are arranged simultaneously.In Chapter 2,the theory of robot kinematics,automatic positioning and navigation and machine vision is analyzed to settle the necessary theoretical foundation for the research of motion control,autonomous navigation and positioning of the tracked robot and visual detection of structure and lesions in building facilities.At the same time,general planning of system is completed after clarifying the functions and goals of automatic inspection system for building facilities based on tracked mobile robot.Key technologies to be solved are summarized.In Chapter 3,the research on motion control,positioning and navigation technology of tracked robot is introduced.The kinematics model of robot and mathematical model of RGB camera,depth camera and IMU are built.Parameter of stair structure can be measured by the image alignment and LSD and Sobel edge detection algorithm.Automatic stair climbing technology based on a multi-source information fusion is completed.At the same time,speedometer information and IMU information are fused by Extended Kalman Filtering,which can improve accuracy of positioning and navigation in building facilities.In Chapter 4,the research of structure and lesion detection technology based on machine vision is introduced.The method of SIFT matching and structure from motion is used to stitch images and get point cloud image which are taken during automated inspection.Point cloud image retaining the depth information of the building facilities.At the same time,lesion in building facilities is segmented by improved U-Net network.The result of segmentation can achieve the goal of crack detection.In Chapter 5,based on the theories and technical achievements developed in the above chapters,key hardware and software modules are developed by adopting a distributed architecture and modular design strategy.The system of building facilities automatic inspection based on tracked mobile robot is complete.And it is used for related experiments including stair-climbing,autonomous positioning and navigation and visual inspection in structure and lesion detection to confirm the feasibility and effectiveness of the technologies and system developed in this paper.In Chapter 6,the research content of this paper is summarized and the further research works are also forecasted.