Who I am
I am Alexander Alexanov, naval architect and marine software designer. I am author and developer of Shaper Maker software. More than 30 years I use Shape Maker for hull lines fairing. Hundreds of different ship hulls was faired during thees years. At same time it helps to continuously improve Shape Maker software functionality. Some secrets of my hull fairing technology I would like to share on the web site.
Why I do this
Sculptural surfaces are a mathematical tool used to modeling surfaces of objects that cannot be presented as a combination of cylinder surfaces, cones, and spheres. Such objects include blades of turbines, wings and hull of airplanes, hull surface of cars and ships. In contrast to the traditional drawing of surface sections and solving the tasks of descriptive geometry manually on the floor, the use of sculptural surfaces greatly facilitates and automates the designer's work. At the same time modelling of sculptural surfaces demands completely other approaches and methods at designing of surfaces of complex form. With all the variety of mathematical methods of surfaces modeling for almost any of them it is possible to define general rules and approaches.
The ease and simplicity of working with sculptural surfaces is just an illusion. Modeling programs give us a happy opportunity not to go deeply into mathematical details in the formation of surfaces, but knowledge of the physical fundamentals of surface behavior will significantly simplify hard work on their assignment and smoothing.
Why I use Shape Maker
Friend of mine found nice and simple program for hull lines fairing. He said he spent just few minutes and hull lines was ready. Only one remark - he is not ship designer or shipbuilder, he is IT specialist. I had spent some evenings surfing in Internet and found a lot of videos with examples of hull lines fairing in different programs. Some of this programs especially design for hull surface modeling, some of them even universal mechanical CADs. So lines fairing is so simple that everyone can do it in any CAD software with NURBS surfaces tools, but in reality it is not true.
If you think you can download some software from internet and in few minutes make hull of your dream - this site and the software is not for you. Most of such programs lets users use classic mathematical methods of surface modeling such us for example - cross sectional design. Results of such methods perfectly correct from mathematical points of view, but in reality can't meet designer's expectations.
Shape Maker has quite unique tools that help's user to make surface he want to make, but not what software dictate. Another great opportunity with Shape Maker - same model from initial design to production. User just change model during design process. For my opinion Shape Maker has best tools for surface quality checking. I can speak a lot about it, but if you want, you can try it yourself here.
History of creation and evolution of the program Shape Maker
The first studies on the application of parametric curves and surfaces were started in the middle of the 80s of the last century at the Department of Applied Mathematics of Gorky Polytechnic Institute in Russia. The start of using a parametric representation of curves for modeling the shape of frames was the first step to automate the smoothing of the ship's surface. As a result, there was a system called Pirs, which was based on the method of kinematic change of the shape of the frames ship along the ship’s hull. The sections of Bezier curves, which were connected together, were used as the functions of the description of the veneer. Despite a number of restrictions it was a well-functioning system, which functioned on the Soviet analogue of the computer PDP-11 of the company Digital Equipment Corporation. The system was used in a number of industrial enterprises of the shipbuilding industry.
In 1991, the IGS (Interactive Graphics Systems) company initiated the development of the Apirs system. It was the first system that used parts of the Bezier surfaces to describe the ship's surface. The system initially had the possibility of topological links between the surface patches and changes in the shape of the patches when the shape of the boundary lines changed. Unlike the existing CAD systems, Apirs did not use orthogonal sections of the hull as boundary lines of surface sections. The shape of the hull changed when the control points of the surface polygon changed, and the sections were dynamically recalculated each time the surface changed. At first, this way of defining the surface shape was very unusual for designers. Despite this fact, the method gave a lot of advantages for a more correct and natural formation of the ship's surface. The Apirs system has been used in many design offices. The method of surface formation was so successful that the system was used even to smooth the shape of the surfaces of submarines and GeV. The system was developed on the basis of computers IBM PC under MS DOC and had an advanced graphical interface. The language of the project implementation was C. The development was conducted almost until 1995 and in subsequent versions of the mathematical apparatus Beziers was replaced by B-spline curves and surfaces.
In 1998, the Nizhny Novgorod company SeaTech (Russia) started the development of a new system of SeaSolution on the basis of the Apirs system. SeaSolution had a Windows interface. C++ was used as the main programming language. SeaSolution has acquired a more developed topology, improved interface and additional possibilities of displaying graphical information. An OpenGL graphics package was used as a visualization tool. For a long time SeaSolution was used to produce faired surface for production workshop documentation and the unfolding of sheets of shell plates. The surface of SeaSolution was transferred to the systems of steel workshop documentation in the format IGES. This format assumes a mathematically accurate representation of the surface without further improvements and changes. In this case, all surface smoothing defects are reflected in the final shape of the case. Several hundred hulls of sea going vessels during this period were smoothed by orders of the Norwegian shipyards.
The high accuracy of the hull assembly and the requirements for surface smoothing allowed to develop a unique vessel surface quality control system. SeaSolution was the first system that allowed not to check the quality of lines by printing a drawing on a large scale. All surface smoothing defects were visible directly in the smoothing process. During this period, most of the work performed in SeaSolution was the final smoothing of the surface for the production of hull workshop documentation. The initial data was the preliminary surface received from the designer of project.
Only C++ is used in the development of the new system. This allowed to get away from a lot of restrictions imposed by C language and significantly accelerate the development of the project. Shaper Maker supports the latest versions of the Windows operating system, has an improved window interface and enhanced User menu functionality. At the same time, the main functions of the system and continuity of the interface were preserved. The main focus of the new development is on the use of the system for surface formation in the initial stages of the project, the interface with different calculation modules and support for the project versions. The system provides the ability to import and visualize the results of the hull CFD calculation. Visualization of the free wave surface, distribution of pressures on the hull of the vessel and stream lines together with the hull of the vessel enables more accurate changes in the hull shape for further optimization. The system of storage of all variants of a surface gives not only representation about stages of formation of a surface, but also allows to use all variants of a surface as a prototype for a new vessel. The wide range of body transformation features makes it easy to change the surfaces of previous projects to quickly create a prototype of a new hull. The undeniable advantage of Shape Maker is that the same model is used from the initial stage of the project to the construction of the finished vessel.
Picture above show on of very first version of the software for hull form modeling.