Master the art of paitron-ing!
Navigate the tutorials: From Digital Model to Results Evaluation, your learning experience awaits…
Formalize the System
1 | Digital Model
Welcome to the paitron tutorial series!
In this video, we will introduce you to our example system: the power supply of an Arduino Uno Rev3, which will be central to your journey throughout this tutorial series.
The Arduino Uno Rev3 is an open-source microcontroller board, making it an ideal reference system to help you grasp the power and potential of paitron in the context of functional safety analysis.
Did you know?
Along with paitron, to illustrate the use of paitron, example projects such as the “Arduino” example project are provided.
These examples are located in the “Model Libraries” folder and visible in the project explorer of the paitron GUI. Detailed documentation about this example can be found in the project folder in “01 Documentation.”
A publication on the Arduino Uno Rev3 analysis with paitron is available here.
2 | Formalize the system
These videos tackle the system formalization. The formalization is needed to decide which variables need to be considered for the analysis, and to specify the relevant scenarios and effects.
- System domains:
- When a range is assigned to an output variable in the “Domains” tab of the system editor, it is strongly recommended that it covers all the real number values – from minus infinity to plus infinity.
- On the other hand, the use of infinite values is not recommended for input variables, as this can often lead to failed simulations.
2. Effects Status Indication: If an effect is marked as inactive in the “Effects” tab of the system editor, it will be denoted with an “_” underscore. Only active effects will be considered later in the generated report.
Beyond the Basics
Automated Output Domain Detection:
Paitron offers a feature that enables automatic suggestion of output domains. To utilize this functionality, navigate to the bottom left of the system editor and click on “Detect Output Domains.” In the ensuing pop-up, utilize the checkbox on the left to specify the output variables for which you wish paitron to execute automatic detection.
Did you know?
In the Domains editor under the “Domains” tab, the use of “-inf” or “min” translates to negative infinity. Similarly, the use of “inf”, “+inf” or “max” is translated into positive infinity.
3 | Analysis Specification
Ready, specify, analyze!
- Analysis option:
- Located at the bottom of the paitron GUI, the “Analysis Options” facilitate the reuse of previously generated failure-injected models and abstraction results if the variables and their domains remain consistent from a prior system analysis.
- After updating the formalized scenarios or effects, you can reuse the failure-injected models and abstraction results. However, note that after updating the simulation model, it is necessary to repeat error injection, as the existing failure models are not automatically updated.
2. Derating: In the “Component Failure Rates” tab of the “FMEDA Excel Sheet,” the stress-dependent factor in the last column (column “AK”) defaults to 1 when information for its calculation is absent. Additionally, some components may lack calculations for the operating conditions factor. In these cases, users are required to provide and justify this information.
Beyond the Basics
Advanced component definitions:
Simplify your workflow by letting paitron handle component definitions. In the System parts editor, click “Configure Parts” within the “Configure Analysis” window.
Use “Reload from Model” to import specifications from the simulation model’s netlist. Alternatively, employ the “Detect using BOM” option to seamlessly import component information from a selected file on your computer.
Did you know?
You can use common keyboard shortcuts like Copy and Paste in the System Parts Editor for quick and intuitive editing.
4 | Results Evaluation
This section covers the analysis results and possible changes the user can make to the results.
1. FMEDA Manager: Components, along with their respective failure modes and failure rates, entered in the FMEDA Manager are exclusively accessible within the corresponding report.
2. FMEDA Analysis Workbook: Within the “Components Sheet” tab of the FMEDA analysis workbook, users can modify failure rates, failure modes, and designate a component’s safety relevance for the analysis. While paitron automatically populates this sheet, users have the flexibility to make revisions. It is essential to note that the failure rates and failure modes employed by paitron adhere to industrial standards; therefore, user modifications in the FMEDA sheet are at their own risk.