SimMechanics

What Can You Do with SimMechanics?

SimMechanics is a set of block libraries and special simulation features for use in the Simulink environment. You connect SimMechanics blocks to normal Simulink blocks through special Sensor and Actuator blocks.

The blocks in these libraries are the elements of a platform for modeling mechanical systems consisting of any number of rigid bodies, connected by joints representing translational and rotational degrees of freedom. SimMechanics can represent machines with components organized into hierarchical subsystems, as in normal Simulink models. You can impose kinematic constraints, apply forces/torques, integrate Newton's equations, and measure resulting motions. You saw some of these features at work in the Conveyor Loader demo model.

Glossary Terms    For an explanation of special terms, see Summary of Technical Vocabulary and the Glossary.

Modeling Machines with SimMechanics

SimMechanics extends Simulink with a library of blocks for specifying a mechanical system's components and properties and solving the system's equations of motion. The blocks are similar to other Simulink blocksets, with some properties unique to SimMechanics.

These are the major steps you follow, using SimMechanics, to build and run a model representation of a machine, with forward links to more detailed explanations:

• Specify body inertial properties, degrees of freedom, and constraints, along with coordinate systems attached to bodies to measure positions and velocities.
• Set up sensors and actuators to record and initiate body motions, as well as apply forces/torques.
• Start the simulation, calling the Simulink solvers to find the motions of the system, while maintaining any imposed constraints.
• Visualize the machine while building the model and animate the simulation while running, using the Handle Graphics or virtual reality-based visualization tool.

Modifying the Model

Bodies, Coordinate Systems, Joints, and Constraints