Partnership with a Tier-1 for Migration of an ECU Application Software to MBD Approach

 
Our customer is a tier-1 supplier of automotive ECUs for hybrid and combustion engine vehicles.

Business Challenge

Our customer has a working automotive ECU control software for one of the vehicle applications developed using conventional coding. There is a growing demand in the market for systems & devices which are compact, customizable, durable and easily maintainable. Owing to this factor, the customer wanted to migrate to the model based design paradigm.

Essentially, the customer was looking for a technology partner with experience in:

• Engineering approach that supports all stages of development with ease of verification & validation. This results in a system that works seamlessly across different environments.
• The approach should be in sync with the existing system with conventional C code.

Embitel’s Solution

Since our team was tasked with migrating an existing system to the MBD paradigm, we first performed a joint analysis and study of the existing systems with the customer’s team. We analysed the different components of the application software and identified the following approach for migration to MBD:

• Model Based Development approach for the development of the application software.
• Development and use of the custom-built Simulink library blocks to match the existing software functions.
• Use of script where the existing application software (.c/.h) files are processed to generate Model and Data Dictionary templates.
• Fixed point modelling.
• Matching the Model Based Development software functionality with the earlier software functionality by Auto code generation using Embedded coder tool.

Development steps in the migration process:

• Scripts are run on the .c/.h files of the existing application modules post which Data Dictionary and model template are generated. The model template consists of the Simulink function subsystems blocks.
• The C code is analyzed, and model is grown by implementing the C function logic inside the Simulink function subsystem block.
• The data dictionary is updated with the data properties similar to the existing system and model is prepared for code generation.
• Model is verified by compiling and upon successful verification code is generated.
• The auto-generated code is compared with the existing C code and reviewed by the customer.
• Post verification, the code is integrated with the existing system where the auto code generated files replaces the .c/.h files of the existing system.
• The MBD integrated software is tested to match the functionality of the existing system.

Embitel’s Impact

• The MBD approach helped to develop the application software system that is easily configurable and
  maintainable to support future changes.
• The use of scripts reduced the development time significantly and also the manual errors intervention during the data dictionary creation.
• We used the Standard library blocks for the PID controllers, inputs filters, n-D lookup tables etc., thereby reducing the development time significantly.
• Model simulation testing helped to identify the issues early.

Tools and Technology

• Matlab
• Simulink
• Stateflow
• Embedded coder
• NXP’s S32 Design Studio for Power Architecture