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The purpose of this paper is to develop the method of generating assembly sequences, which can be used in the shipbuilding industry. The method must take into account the assumptions specific for assembly processes of large-size steel ship hulls, among others, a large number of connections, multi-stage and parallel assembly, set priority relations between connections.

The assembly sequence is presented as a directed acyclic graph, whose vertices are mutually uniquely assigned to connections on a hull structure. The minimization of the number of unmet priority precedence of performing connections has been proposed as a criterion of optimization. The genetic algorithm has been proposed as a method to solve problems.

The proposed method allows to model the acyclic assembly process of welded structures and find solutions minimizing the objective function even for very complex problems. Because of this, the method has a chance to be used in shipbuilding.

Mathematical formulation of priority assumptions is quite laborious. The possibility of partial automation of this process should be considered. Due to the complexity of the problem, a relatively simplified objective function has been proposed. In assembling a hull, additional criteria should be taken into account. It is the direction of further research.

The method can be successfully used in shipbuilding and in planning the production of other steel welded structures, among others, tanks, components of bridges, offshore structures. Examples of calculations were performed on an actual structure of a hull fragment.

A new way of coding the acyclic serial-parallel sequence was designed. The proposed method allows to analyse the sequence using the graph theory. Original, two-part crossover and mutation operators for assembling sequence were proposed.

The purpose of the paper is to develop a method of automatic classification of the components of the assembly units. The method is crucial for developing an automatic ship assembly planning tools. The proposed method takes into account the assumptions specific for shipbuilding technology processes: high complexity of structures, difficult expert-based classification of components, fixed priority relations between connections resulting from geometrical constraints and demands of welding processes.

The set of ex post determined liaisons and assembly sequences constitutes the database of structures which have been made-up earlier. The components classification problem is solved using matrix coding of graphs. Information in such form is stored in the database. The minimization of number of cycles in the graph of classes sequence and minimization of diversity of classes within all constructions has been proposed as criteria of optimization. The genetic algorithm has been proposed as a solution method.

The proposed method solves the problem of components’ classifications. It allows setting the pattern of priorities between classes of various connections. This gives a chance to determine the relationship constraints between the connections of new structures for which assembly sequences are not established.

Mathematical formulation of the database is quite laborious. The possibility of partial automation of this process should be considered. Owing to the complexity of the problem, a relatively simple objective function has been proposed. During a ship hull assembly, additional criteria should be taken into account, what will be the direction of further research.

Automatic classification of components is dedicated for implementation in shipyards and similar assembly systems. Tests performed by the authors confirm efficiency of presented method in supporting management of the database and assembly of new structures planning. Suggested activity-oriented approach allows for easy conversion of any assembly unit structure to the form of a matrix.

The new approach for components classification according to its assembly features distinguishes the proposed method from others. The use of nilpotent matrix theory in an acyclicity of graphs analysis is also a unique achievement. Original crossover and mutation operators for assembly sequence were proposed in the article.

Marking and inspecting are key steps in hull structure construction. However, currently most marking and inspecting operations are still carried out manually, which leads to low assembly efficiency and quality. This paper aims to solve these problems through the application of digital technology: the optical projection and machine vision.

First, the assembly process model of hull construction is established in 3D design environment. Second, the process information is presented to workers in a virtual form through optical projector, which provides accurate guidance for the manual operation. On this basis, the workers can complete welding and assembly operations readily. Finally, the machine vision method is used to check the assembly results, which can decrease the subjective errors.

A rapid and accurate assembly positioning for hull structure construction is realized based on optical projection, which can avoid the pollution caused by the marking machine and the error caused by human.

This paper combines the advantages of optical projection and machine vision to the field of shipbuilding. The shortcomings of the traditional marking and inspection methods is effectively solved, which may provide a new way for enhancing the assembly efficiency and quality.

IT is indeed an honour to appear before you to address you on the subject “American Methods of Aircraft Production.” We in America have long held the Royal Aeronautical Society in high regard, amply justified by the excellence of its published papers and the example it has set in organisation and in the conducting of an aeronautical society. Indeed, a few years ago when several of us in America decided that we, too, should have an aeronautical society, we planned our own organisation very largely on yours. We are very much pleased that the relationship which has existed between your Society and the Institute of the Aeronautical Sciences in America throughout the brief career of the latter has been so close and friendly and I can assure you that we intend to do everything possible on our part to continue this highly desirable condition.

THE ZMC‐2 hull is 149 ft. 5 in. long from bow to stern, and 52 ft. 8 in. in maximum diameter. Its covering consists of 0•0095 in. thin Alclad alloy sheets sewn together by the Aircraft Development Corporation riveting machine. Each of the rings of sheet metal composing the hull surface has the shape of the frustum of a cone; together the cones closely approximate the curvature of the hull. There are 142 such conical surfaces from bow to stern.

This paper overviews work on a computer based consultation system, which uses artificial intelligence principles, and has been designed to aid the non‐specialist engineering designer or production engineer in the domain of design for assembly.

CAREFUL inspection and maintenance of hulls and floats is of the utmost importance, as a forced or heavy landing with a hull or float which is in a doubtful seaworthy condition might easily result in the total loss of the sea‐plane.

Hull block assembly is a vital task in ship construction. It is necessary to obtain the actual poses of the assembly features to guide further block alignment. Traditional methods use single-point measurement, which is time-consuming and may lead to loss of key information. Thus, large-scale scanning is introduced for data acquisition, and this paper aims to provide a precise and robust method for retrieving poses based on point set registration.

The main problem of point registration is to find the correct transformation between the model and the scene. In this paper, a vote framework based on a new point pair feature is used to calculate the transformation. First, a special edge indicator for multiplate objects is proposed to determine the edges. Subsequently, pair features with an edge description are noted for every point. Finally, a voting scheme based on agglomerative clustering is implemented to determine the optimal transformation.

The proposed method not only improves registration efficiency but also maintains high accuracy compared to several commonly used approaches. In particular, for objects composed of plates, the results of pose estimation are more promising because of the compact pair feature. The multiple ship longitudinal localization experiment validates the effectiveness in real scan applications.

The proposed edge description performs a better detection for the edges of multiplate objects. The pair feature incorporating the edge indicator is more discriminative than the original template, resulting in better robustness to outliers, noise and occlusions.

Examines the development of courses in robotics and advanced automation at UK universities and describes the relationship between industry, research and the courses. Looks in detail at undergraduate courses offered by the universities of Hull, Bristol, Plymouth and Leeds Metropolitan university. Describes the pioneering postgraduate course at Cranfield University. States that the collaboration between these universities and industry and the support this collaboration provides has been essential for the viability of the courses. Concludes that the future is bright for these courses so long as they are well presented to potential students and the industrial sector remains committed.