Introduction to Rapid SysML Simulation Debugging

Introduction to Rapid SysML Simulation Debugging
1. Common Issues
*Incorrect or incomplete SysML model
**To execute action you require tokens in all action inputs
**State does not stays active if transition from state has no trigger or guard
**No signals on sent / accept event actions
**Parametric diagram constraint block parameters are not connected
*Elements in the model are not the same as in the diagram
**Deleted symbol from diagram but not from the model (use Ctrl + D)
**Copy pasted symbol in diagram.. Element is still the same
*No classifier behavior is assigned
*Classifier behavior is assigned but execution is not in context
*Variable names does not match
2. Common Time Issues
*Time parameters are not specified
*Clock does not start
*No duration constraints - time is based on animation speed
*Chart refresh rate is too high
3. Animation
4. Breakpoints
5. Runtime Value Monitoring, Watch Pane
6. Console pane
7. Rule #1 - Large Simulation - Fast Debugging!

[@BruceDouglass]

Very nice, as usual. I would only add to your last point by recommending modelers do highly frequent execution during model creation, every few minutes to ensure that defects don't get entered into the model in the first place. The far more common - and painful - approach is to spend days to weeks entering model elements and only at the end beginning to execute. It is far better to execute every few minute during model creation and avoid the difficulty of tracking down many hidden defects. I recommend to my staff that they go no more than 30 minutes between demonstrating model correctness through execution.

[@MBSEExecution]

Thank you Dr Bruce for the great adition.

[@brettany_renee_blatchley]

Bumper Sticker Computer Science: Never Write a Big Program. (Create big programs by incrementally creating & testing small programs that combine into The Big Program.)

[@MBSEExecution]

Well said!

[@brettany_renee_blatchley]

Along the lines of "divide & conquer," I had had a couple nasty issues lately that I spent a lot of time chasing. Finally, in each case, I prepared a bare-bones (toy) example to share with 3DS support, and in that process of isolating the issue/feature/model-fragment, I found my issues disappeared. THIS told me that the feature in question basically works, but there was something in my larger model that was causing the issue. Knowing this, I looked to see what could be different between the toy and the real model, and between this and altering the toy in controlled ways, I was led to the problem in each case.

[@MBSEExecution]

Thank you for sharing great example!