Major Bug Fixes for SimMechanics 2.0

This document describes major bug fixes for SimMechanics 2.0.  Click on a problem area listed below to read how it has been fixed.

Accelerator code now builds once
Command line interaction with models
Handle Graphics animation freeze
Handle Graphics animation from a subsystem
Inactive Body Actuator not allowed
Joints connected to Bodies connected to Gear Constraints
Saving SimMechanics models while simulation is paused
Undeleting a Body no longer resets Adjoining coordinate systems to World

Accelerator code now builds once

When you run a model in Accelerator mode, the necessary code is now generated only once. Version 1.1 of SimMechanics worked with Accelerator mode, but rebuilt the necessary code every time the model was started in that mode.

Command line interaction with models

The Simulink sim and model commands allow you to run models from the command line, including models with SimMechanics blocks. model allows execution of intermediate phases of a simulation and was broken in earlier versions of SimMechanics. The sim command is equivalent to the Start button. See the Simulink User's Guide and the section on simulating dynamic systems.

Handle Graphics animation freeze

Handle Graphics visualization in earlier versions of SimMechanics froze if you made an incorrect Handle Graphics change while a model was running. This bug is now fixed.

Handle Graphics animation from a subsystem

In earlier versions of SimMechanics, Handle Graphics animation did not always properly update if the model was started from a subsystem. This bug has been fixed.

Inactive Body Actuator not allowed

You can apply a force and/or torque to a body with a Body Actuator by selecting the appropriate dialog check boxes. But you can no longer unselect both check boxes and leave the Body Actuator inactive. You must select force or torque actuation, or both, before closing the dialog.

Joints connected to Bodies connected to Gear Constraints

The Gear Constraint in earlier versions of SimMechanics sometimes resulted in errors if the Bodies to which the Gear Constraint was connected were in turn connected to the third, common Body by certain Joints. The Gear Constraint now works with any type of Joint connected to the common, third Body.

Saving SimMechanics models while simulation is paused

If you pause a SimMechanics model while it is running, you can now save it. Simulink disallows use of Save as for paused models, however.

Undeleting a Body no longer resets Adjoining coordinate systems to World

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 no longer reset to the World CS but remain correctly set to the Adjoining CSs.