Model body geometries, inertias, colors, and frames

Model the bodies that comprise your multibody system. Treat each body as a group of rigidly connected solid sections. Represent the solid sections using the Solid block and connect them using Rigid Transform blocks or direct frame connection lines. For an overview of the body modeling steps, see Creating Body Subsystems. For an example showing how to model a body, see Model a Compound Body.

Simscape Blocks

Graphic Marker with graphic properties
Inertia Mass and inertia tensor of solid mass
Solid Solid element with geometry, inertia, and color
Spline Cubic interpolating plane or space curve
Reference Frame Non-inertial reference frame
Rigid Transform Fixed spatial relationship between frames
World Frame Inertial reference frame


smnew Open Simscape Multibody model template and block library
sm_lib Open the Simscape Multibody block library

Examples and How To

Solid Geometries

Model a Solid of Revolution

Use the Revolution shape to model a solid with a constant cross section about an axis.

Model an Extruded Solid

Use the General Extrusion shape to model a solid with a constant cross section along an axis.

Model a Compound Body

Combine solid elements with rigid transforms to obtain more elaborate rigid body geometries.

Frames and Inertias

Add Frames to Solids

Interactively create new solid frames using the Solid block frame-creation interface.

Specify Custom Inertia

Calculate and manually specify the moments and products of inertia for a simple solid.


Modeling and Visualization

Creating Body Subsystems

Workflow steps for modeling rigid body subsystems from individual solid elements.

Simscape Multibody Bodies

Overview of the solid properties common to all rigid bodies. Role of coordinate frames in rigid body subsystems. Software definition of rigid body boundaries.

Solid and Multibody Visualization

Solid block and Mechanics Explorer as visualization utilities for solids, bodies, and multibody subsystems.

Solid Properties

Solid Geometry

Overview of the solid shapes available in the Solid block. Preset shapes, compound shapes, and imported shapes.

Revolution and General Extrusion Shapes

Rules for specifying cross-section coordinate matrices for General Extrusion and Revolution solid shapes.

Solid Inertia

Simscape™ Multibody™ definitions of moments and products of inertia. Parameterizations and approaches for specifying inertia in simple and compound rigid bodies.

Solid Visual Properties

Using solid color parameterizations to manipulate solid opacity and shadow, highlight, and self-illumination colors.


Frames and Frame Transforms

Definition of frame, role of frames in a model, and frame transforms as spatial relationships between frames.

World and Reference Frames

Roles and characteristics of global and local reference frames in a model.

Representing Frames

Using rigid transforms to specify spatial relationships between coordinate frames.


Common Issues with Frame Connections

Modeling practices to avoid when adding or modifying frame connections.

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