Building on Rhino's powerful 3D modeling capabilities, Orca3D provides marine-specific tools for hull design and fairing, hydrostatics and intact stability, and more. With the Orca3D plug-in, you can conceptualize, model, and analyze your design in a single environment, without the tedious and error-prone task of transferring your design from one program to another, or the need to learn a new user-interface.
The process of hull design is more than simply aesthetics; the hull must meet various other requirements, including overall dimensions, displacement, center of buoyancy, and stability. Therefore, the process of hull design and the analysis of hydrostatics and stability must be closely linked. In Orca3D, the model for these tasks is one and the same; the hull is designed using one or more NURBS surfaces, and these same surfaces are used in the calculation of the hydrostatics and stability properties. In fact, they are so closely linked, that the hydrostatics can be updated in real time, as the hull surface is modified.
Orca3D computes intact hydrostatics at one or more waterlines, or multiple displacement/center of gravity combinations. In addition, at each of these conditions, the righting arm curve may be computed. Computed values include:
Because Orca3D computes the hydrostatic properties based on the surface model, using first principles, there is really no limit to the type of vessel or object that it can analyze. Monohulls, multihulls, vessels with propeller or bow thruster tunnels...basically, anything that floats, or even sinks, can be analyzed with Orca3D.
Graphical output consists of a planar surface inserted at the equilibrium flotation plane, with the LCB and LCF annotated.
Orca3D produces a report that includes tabular data at each flotation condition, as well as plots of appropriate parameters. The report is created and displayed using Microsoft Report Generator; the file may then be printed, or saved in Adobe Acrobat® (pdf) or Microsoft Excel® format. Examples of portions of the output are shown below.
Since Orca3D uses the surface model to compute the hydrostatics and stability, it is very forgiving with regard to the model. The requirements are as follows:
The design of a vessel in Orca3D begins with the hull model. Hull design is a unique combination of artistic expression and engineering analysis, combining to form a creative process to meet the aesthetic and performance requirements of the vessel.
The software that you use to transform the hull from an idea to a 3D computer model should enrich the creative process, with guidance provided by precise and detailed analyses. With Orca3D, you have complete freedom to create any type of hull, beginning with a concept and carrying through to final fairing, while ensuring that the hull meets your target hydrostatic properties.
In Orca3D, the hull is created as a NURBS surface. While Rhino provides many important surface creation and editing tools, Orca3D adds capabilities that are specific to hull design, such as:
Any type of hull and hull feature may be modeled. Hulls may be created as a single surface, or when appropriate, multiple surfaces. Tools like blending, trimming, and filleting provide tremendous capability and flexibility.
|An example of a large commercial ship. This model consists of three surfaces; the hull, the deck, and the transom. Note the integrated bulbous bow, perfectly faired into the main hull, since it is all part of the same surface.|
|Chine hulls are easily modeled and analyzed, with as many chines, knuckles, or style lines as desired.|
|This sailboat model shows the importance of a smooth transition from the stem to the bottom; not just slope continuity, but also curvature continuity. Orca3D makes it simple to ensure this higher degree of fairness.|
In addition to hull fairing tools, Orca3D provides a new tree control to help you to organize your model. It's another view into your layers, but with the addition of individual objects. This makes it easy to name objects, select them, change their properties, and drag them from one layer to another.
Another nice feature of the tree is the ability to quickly focus in on part of the model; simply right-click on a layer, sublayer, or object, and select "Set View Part." The rest of the model will then become hidden.
"How fast will it go?" The Orca3D Speed/Power Analysis module has two different prediction methods: the Savitsky method to predict the speed/power curve for chine hulls, and the Holtrop method to predict the speed/power for displacement hulls. We have integrated the HydroComp Drag Prediction Library, to ensure reliable, accurate results.
Most of the required input parameters are automatically computed from your model, although the user can input or override the values. Results are quickly generated and professionally formatted, and include checks to ensure the validity of the results. Any parameters that are outside of the ranges of the prediction method are flagged.
The results of the analysis are presented in easy-to-read reports, which include a summary of input data, checks of the parameters of your design versus the limits of the analysis method, and performance data versus speed. Plots of various parameters are also included, and the entire report may be printed or exported to Microsoft Excel or PDF.
In addition to predicting the performance, the analysis gives insight into how to improve the performance, with a Drag Reduction Analysis. Four key parameter are evaluated, and recommendations given on adjustments to optimize your design; Planing Beam, Deadrise Angle, LCG location, and Shaft Angle.
The success of any design hinges on its weight and center of gravity. These parameters are fundamental to stability, speed, capacity to carry cargo (whether it be passengers, containers, or weapons), seakeeping performance, etc. Weight and CG tracking therefore must be a fundamental part of any design process.
Cost is another critical factor in the success of a design, and good engineering practice calls for cost considerations to be closely tied to the design process.
Orca3D's Weight/Cost Tracking module adds value to your Rhino model by assigning weight and cost parameters to the objects in the model, and summarizing and presenting the data.
For example, a surface that represents a portion of the hull can be assigned a weight per unit area, and as that surface is modified, the total weight and center of gravity updates automatically. The cost parameter is broken down into material cost and labor cost, and can also be assigned on a per unit area basis. Similarly, curves can be assigned values on a per unit length basis, and solids can have either per unit area or per unit volume values. Also, curves, surfaces, and solids, as well as point objects, can be assigned an absolute value for weight and/or cost, that will not change as the object is modified.
To simplify the process of assigning weight and cost values to your objects, Orca3D includes the ability to create a library of stock materials, and you can assign a stock material to the objects in your model. For example, you might create "5 mm steel plate," with a unit weight per square meter, a material cost per square meter, and a labor/fabrication cost per square meter.