Overview

This document provides a high-level overview of the different components that make up Ansys Behavior Execution Engine for SysML v1.

Delegates and delegate modules

A delegate is a Java interface or class that represents a one-to-one correspondence between itself and a block in your model. A delegate class contains custom code that implements the properties and operations of a block. This code is executed when the opaque expressions in state machines are evaluated at simulation runtime. Though any arbitrary Java code may exist inside a delegate, you reap the true benefit of Behavior Execution Engine when you use delegates to integrate the analytical rigor of physics-based analysis tools to precisely drive state machine transitions in a simulation.

Collectively, all delegates used for a particular analysis tool are referred to as a Delegate Module.

Behavior Execution Engine also enables you to have two or more delegate implementations for any given block. Depending on the application, these implementations may contain entirely different logic or even use different analysis tools. You may then specify which implementation to use for each Instance Specification by applying the appropriate stereotype. For more information, see the Stereotypes help topic.

For a comprehensive guide to developing delegates and using them in your simulations, see Developing Delegates.

Reports and utilities

Model validation report

The model validation report runs a validation process against your state machines and the model elements referenced within them. This checks whether the opaque expressions that reference properties and operations are in agreement with their corresponding blocks and delegates, and that they are compatible with Behavior Execution Engine. The validation process looks for naming inconsistencies, invalid access usages, incorrect return types, and many other issues.

When the process is finished, it presents you with a list of detected errors and warnings in your default text editor. Each error and warning in the report is paired with the ID and qualified name of the offending element in your model. Use this tool early and often when developing your simulations to identify issues all at once, so you can correct them prior to execution. You can find the model validation report in the Diagnostics page.

The model validation report will not always catch everything that could go wrong with your simulation. Sometimes there may be a configuration error or a bug in the delegate code that causes your simulation to fail at runtime. In this case, the best place to look is in the simulation log file.

For more details, see the Model Validation help topic.

Delegate availability report

The delegate availability report shows the canonical Java class names of the delegate and delegate modules that the current simulation will load. This report helps to verify that the delegate modules have been deployed correctly and do not conflict with each other when multiple modules are loaded together. In addition, it shows the qualified name of the block each Java class represents. You can find the delegate availability report in the Diagnostics page or in the Actions menu.

Block usage report

The block usage report lists all properties and operations currently in use by the state machines defined within your simulation. With this information, you can identify missing state machine elements or determine whether or not an element is referenced incorrectly. You can find the block usage report in the Diagnostics page.

Delegate code generator

The delegate code generator utility generates Java interfaces and classes based on your model that are compatible with the Behavior Execution Engine delegate architecture. You can find the delegate code generator in the Code Generation page.

For more details, see the Delegate Code Generation help topic.

Runtime code generation

As your simulation executes, Behavior Execution Engine automatically generates default delegate implementations for model types that do not require custom implementation.

Model libraries

Behavior Execution Engine includes three model libraries: a required base for all simulations, a geometry core that you can extend for specific domains, and a helper for connecting to the STK application.

Balloon Ride reference application

Behavior Execution Engine includes a sample reference application depicting a simplified one-dimensional hot air balloon ride. This sample will help you understand how the pieces of Behavior Execution Engine fit together without having to deal with complicated physics or to integrate external tools. You can find the SysML project and the associated delegate source code in the \samples\balloonRide directory of the installation. You can open the Behavior Execution Engine Installation Directory directly from the Windows Start menu or Taskbar search box.

Tutorials

The Behavior Execution Engine tutorials will guide you through applying the above concepts to create and utilize a complete Behavior Execution Engine simulation from the ground up. The tutorials are broken up to give you the flexibility to practice individual concepts without having to step through everything from the very beginning.

For more details on SysML v1 simulation tutorials, see the SysML v1 Simulation Tutorials.