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Recent development of laser scanning device increased the capability of representing rock outcrop in a very high resolution. Accurate 3D point cloud model with rock joint information can help geologist to estimate stability of rock slope on-site or off-site. An automatic plane extraction method was developed by computing normal directions and grouping them in similar direction. Point normal was calculated by moving least squares (MLS) method considering every point within a given distance to minimize error to the fitting plane. Normal directions were classified into a number of dominating clusters by fuzzy K-means clustering. Region growing approach was exploited to discriminate joints in a point cloud. Overall procedure was applied to point cloud with about 120,000 points, and successfully extracted joints with joint information. The extraction procedure was implemented to minimize number of input parameters and to construct plane information into the existing point cloud for less redundancy and high usability of the point cloud itself.

It is very important to measure and diagnose the state of knife and strip cutting face in real time in the side trimming process due to improvement of quality of strip trimming face. In this study, a diagnosis system for knife and strip cutting face was developed. Two CCD cameras facing each other are mounted at the delivery side (the entry of the bur masher roll) of the side trimmer. This system offers the operator the diagnosis result of state of knife and strip cutting face. With the help of the developed system, the knife breakage has been detected 100% and bad quality of trimming face is significantly decreased. Using CCD cameras, an on-line diagnosis system which can determine knife breakage and bad quality of trimming face in real time is developed in trimming. A diagnosis algorithm determining the state of the strip cutting face is also developed by calculating characteristic values and image processing based on the images of the strip cutting face obtained from CCD camera.

The influence of the flow phenomenon of the cooling nozzle affecting the rod temperature and the factors affecting the cooling efficiency were examined through experiments and numerical analysis. The optimal conditions featuring excellent cooling efficiency can be deduced in the future by analyzing the flow conditions and design conditions.

Extensive width reduction of slabs is an important technology for achieving continuous production between the steelmaking and hot rolling processes. However, the vertical horizontal rolling process has many disadvantages, e.g., large width deviations and less efficient width reduction. This study was carried out to investigate the deformation of slab by sizing press with two steps die. To do it, dog-bone and camber are discussed in width sizing process considering the deformation behavior according to the deviation of anvil velocity and the deviation of initial slab temperature. In this paper, the various causes of the sizing press phenomena are mentioned for the purpose of understanding of rolling conditions. As a result, the optimal anvil shape having a minimum-forming load is obtained by FE-simulation and ANN.

A finite element-based approach is presented for the prediction of the thermal behavior of the strip occurring in the finishing mill during hot strip rolling. The approach, which is fully coupled and three dimensional, is described in detail. The validity of the proposed approach is examined through comparison with measurements. Then the capability of the approach to predict the detailed aspects of the thermal behavior is demonstrated through an application to revealing the effect of an edge heater.

Investigated via a series of finite element process simulation is the effect of diverse process variables on some selected non-dimensional parameters characterizing the thermo-mechanical behavior of the strip in hot strip rolling. Then, on the basis of these parameters an on-line model is derived for the precise prediction of roll force and roll power. The prediction accuracy of the proposed model is examined through comparison with predictions from a finite element process model.

The present work introduces a new type of numerical analyzing method: the contact element method with two relative coordinates (CEM). The main characteristic of the procedure is elements meshing on the basis of the contact length between objects and that each element has two relative coordinates. The ordinary expression of this procedure is DX[CXY(i)]=DY[CYX(i)]. Through this method, the CEM function of the 20-high Sendzimir mill and the deflection function expression of every roll are obtained. A computational software SM4SM for the Sendzimir mill has been developed, by which the deflection condition of rolls S, O, I, and A can be obviously seen. The results obtained by CEM have also been compared to that by the finite element method.

A three‐dimensional and integrated, Eulerian finite element based model is presented for the prediction of temperature, sliding velocity gradient and pressure of roll groove in the hot rod rolling. The model is comprised of basic finite element models, which are incorporated into an iterative solution procedure to deal with interdependence between the thermo‐mechanical behavior of the workpiece and that of the roll. The capability of the model to reveal detailed aspects of the complex interaction between the workpiece and the roll groove is demonstrated through a series of process simulations.

Automated visual inspection promises to play an important role in the factory of the future. A prototype automatic computer vision inspection system was developed for the Quick Turnaround Cell (QTC) at Purdue University. The objective of the QTC project is to integrate design, process planning, cell control, and inspection functions into a manufacturing system that quickly produces parts using little operator knowledge and intervention. This paper focuses on the vision inspection module of the QTC project. To achieve a truly flexible automated visual inspection system, an interface between computer vision processes and CAD databases is an essential step. A design-feature based representation which includes dimensions and tolerances of the part is introduced as the part specification. A 3-D boundary representation CAD model is generated from the high level description. An interface system that understands the geometric shape of the part based on the CAD model generates a vision data base which serves as a front end to the inspection planning system. This planning system automatically generates inspection and recognition procedures from the design data. The recognition planning subsystem uses rules to select the important vision features from the given CAD data base, generates a list of simultaneously visible features, and suggests appropriate matching constraints. The inspection planning subsystem interprets each engineering specification of the part and provides proper inspection procedures. The on-line inspection subsystem executes programs based on the planning results and returns information about the part based on all the dimensions which are measured to subpixel accuracy. Thus, after the design cycle, parts can be throughly inspected with no technical decisions or programming required. Finally, results of experiments produced by the current implementation of the system are illustrated.