Shape Maker. Use of the shear function to modify the hull of the fishing vessel.

Often in the process of designing fishing vessels, it becomes necessary to change the keel inclination angle of the vessel or the inclination of the flat - keel bottom. As a rule, the whole hull should not be changed, but only the part that is close to the bottom. For this, it is most convenient to use the shear function. The rotation function can also be used, but the resultant shape of the frames will be very different from the original. For a shear, it is sufficient to select the shifted elements, the shear center and the shear angle. It is also recommended to set the area of change of lines and surfaces associated with transformable elements.

Fig. 1 Example of changing the keel angle. Only part of the surface is affected.

In Fig. 1 shows the change in the angle of inclination of the keel. For the transformation of the shear, only the lines forming the surface of the keel and the lines of the flat bottom are chosen. In this example, the bottom is flat. As the center of the shear, the point on the mid-frame is selected. All surfaces and lines that are associated with the objects selected for transformation are automatically modified. The area of change of these lines depends on the chosen method of transformation and the number of selected control points. This allows you to quickly change the case and not disturb the smoothness of the surfaces being transformed.

Fig. 2 Changing the angle of the bottom.

 In Fig. 2 shows an example of the change in the angle of the bottom. As lines for transformation, the lines of the flat bottom and the lines of the flat part of the mid-frame and the line of the bilge radius were selected as shown in Fig. 3.

 Fig. 3 Lines selected to change the keel angle.

 As the center of the shear, the point of connection the main surface to the horizontal keel on the midship frame is chosen. With this transformation, the flat part of the bottom remains flat and the tangents in the area of the connection to the flat bottom are also preserved. Also, the shape of the midship - the frame - is naturally transformed.