SimMechanics Release Notes

Known Software and Documentation Limitations

This section describes known software and documentation problems in Version 1.1.

Platform Limitations

The SimMechanics virtual reality visualization has some platform limitations, as described below.

Virtual Reality Toolbox Viewers

• The default viewer functions on UNIX/Linux platforms, but only with virtual reality code written in the VRML 2 standard.
• The blaxxun Contact plugin viewer works only on Windows platforms. It can read virtual reality code in both VRML 1 and VRML 2 formats.

Saving SimMechanics Models

You cannot save a SimMechanics model while the model is paused. If you want to save it, stop the model simulation first.

Changing Block Properties

You cannot change SimMechanics block properties at the command line.

Configurable Subsystems Limitation

Simulink configurable subsystems work with SimMechanics blocks as long as all of the block choices have consistent port signatures.

Unsupported Nonvirtual Subsystems

For Iterator, Function-Call, Triggered, and While Iterator subsystems cannot contain SimMechanics blocks.

Currently Unsupported Simulink Features and Tools

Certain Simulink features and tools are currently not functioning with SimMechanics blocks or SimMechanics models.

Adjoining Coordinate Systems After Undeleting a Body

If you delete a Body, then undo the delete, and this Body references Adjoining coordinate systems (CSs) on neighboring Bodies, the restored Body's CS references that were to Adjoining CSs are reset to the World CS. Fix this bug by immediately updating the diagram after the undelete. Select Update diagram from the model Edit menu, or enter Ctrl-D at the keyboard.

Inactive Body Actuator Causes MATLAB to Crash

You can apply a force and/or torque to a body with a Body Actuator by selecting the appropriate dialog check boxes. If you clear both check boxes, however, MATLAB crashes when you begin the simulation. Either apply an actuation signal or eliminate the inactive Body Actuator from your model.

Virtual Reality Visualization

The presentations of virtual reality visualization in the SimMechanics User's Guide assume that you are using the new default viewer. Consult the Virtual Reality Toolbox documentation for instructions on using the optional blaxxun Contact 4.4 plugin viewer for Web browsers. You must use the plugin viewer if you want to view virtual reality scenes written in the VRML 1 format.

Rendering and Animation Bugs

These are sporadic minor problems with the blaxxun plugin viewer:

• If the machine is not initially visible in the browser, try closing the browser and restarting, or try the browser's Refresh or Reload buttons.
• When you update a diagram, the virtual reality scene might not update as it should. Click the browser's Refresh or Reload buttons to update the scene manually.

Internet Explorer Bugs

Microsoft Internet Explorer sometimes malfunctions while viewing a virtual scene through the blaxxun plugin viewer.

• You sometimes see a nonfatal console error dialog while viewing a virtual scene. Click on OK in this dialog if you see this error.
• Microsoft Internet Explorer 6 sometimes fails if you use it as the default browser for virtual reality. Restart the visualization from the Mechanical Environment Settings dialog if this happens.

Upgrading from an Earlier Release