Beschreibung

This tool helps to draw any open, closed, cut,holed 2D cross section, extrude to 3D geometry and then calculatemass moment of inertia properties. These are useful for structuralmechanics and dynamics performance prediction. Mass moment ofinertia is critical for mechanical, rotation, dynamics performanceprediction. Mass moment of inertia may also be termed as rotationalinertia, polar moment of inertia, or the angular mass.

MI properties for a standard shapes can be obtained from a listof table or standard formula. But for irregular shapes andnonstandard sizes, the mass properties are not readily available.This tool allows you to draw any shape, extrude and then calculategeometric and inertial properties for any arbitrary shape.Geometric and MI properties of any regular/ standard shape can alsobe predicted, by taping the cross section.

Draw non intersecting outer by tapping the vertex of your 2Dcross section. Draw your geometry using both free hand and straightlines. You can also create a hole or cut by tapping the vertex ofyour cut or hole. A unit depth of extrusion and unit density isassumed for mass property prediction. Then click “mass MI” tocalculate the mass properties. The default drawing window size is 2m and snap size is 0.02 m. You can change by tapping the settings.You can also edit the X,Y coordinates of the vertex for moreaccurate numeric input. Select your convenient Units. Set thewindow size to the maximum size of your 2D shape. This size can beset to any size from nano meter (10-9) to giga meter (10+9). MassMI Lite tool supports any shape bounded by non-intersecting outerstraight line segments. Draw by tapping the vertex in clock wise orcounter clock wise pattern. Avoid crossing of the boundary. The endpoint can be closed by tapping close end. Clear, Undo, Edit andCloseLoop buttons are useful to start with any shape, edit thevertex to change shapes, add lines, or move lines and or close theboundary.

The mass moment of inertia is a measure of the 'efficiency' ofany shape to resist rotation. Mass MI is the property of a rigidbody that determines the torque needed for a desired angularacceleration about an axis of rotation. Moment of inertia dependson the shape of the body and the axes of rotation.

The geometry of any arbitrary shape can be defined using nonintersecting external boundary lines. The area bounded by theselines is calculated using area integration method. The externalboundary is represented by linear piece-wise straight lines. Ageneral formula for the moments of arbitrary shape bounded bystraight lines is derived leveraging Green’s theorem fortransforming domain to boundary integrals. This formula isimplemented as an algorithm for computing inertial properties.

The tool prediction results for standard shapes are comparedwith Formulas from text book, Numerical Integration solution usingIndustrial FEA solvers. For straight lined boundary based geometrythe prediction accuracy is very high. For curved boundary theaccuracy can be improved by increasing the number of vertex. Butfor arbitrary shapes such as corroded or damaged members, custombuilt sections, 3D printed shapes, complex designs, Mass MI LITE isthe only tool which will help to predict mass properties.

The number of vertices is limited to 14 and functionalities(open, save, import, export, share) are limited to 5 in this freeversion. The Pro version will enable you do draw any shape withvirtually unlimited vertices and functionalities. The Pro versionis fully functional with A, V, m, Ixx, Iyy, Ixy Properties, XYcoordinates, Holes, composite sections, save, data import/export,suggestions and share functionalities.
For additional support or help

Visit: http://apps.atoa.com/index.php/atoa-apps/mass-moment-of-inertia-Lite
mail: MassMILite@apps.atoa.com