Automotive: Software Defined Vehicles

Reference Architecture: The Data Engine

The modern car generates 25GB of data per hour. The challenge is moving it to the cloud without bankrupting the company on 4G costs.

The Culture War: Mechanical vs Software

The fundamental friction in automotive is not technical; it's cultural.

• Hardware Culture (The Default): "We bend metal. Once the die is cast, making a change costs $50M. Plan everything for 5 years." (Waterfall).
• Software Culture (The Invader): "Code is fluid. Deploy every day. Fail fast." (Agile). Result: When you force Agile on a Hardware culture, you get "Water-Scrum-Fall"—2 week sprints that result in zero releasable code for 3 years.

The Protocol War: CAN vs Ethernet

Your architecture is defined by how bits move.

• Legacy (CAN Bus): Reliable, but slow (1 Mbps). It's a broadcast network—everyone shouts, everyone listens. Great for brakes; impossible for 4K video.
• Modern (Automotive Ethernet / SOME/IP): Service Oriented. You don't "shout"; you "subscribe".
  • Rationality: You cannot build an SDV on CAN. If your architecture is primarily CAN-based, you are building a "Smart Feature Phone", not a Smartphone.

The Vendor Trap: Gray Box vs Black Box

• Black Box (Traditional): You buy an ESP (Electronic Stability Program) from Bosch. It saves lives. You cannot read the code. You cannot patch the code. If it bugs out, you file a ticket and wait 6 months.
• Gray Box (Modern Partnership): You co-develop. You own the IP for the "Secret Sauce" (e.g., Regenerative Braking feel), while the vendor supplies the commodity drivers.
• In-House (Tesla/BYD): You write everything.
  • Rationality: Do not attempt In-House unless you have $10B in cash. The validation costs alone will bankrupt you.

Regulatory Reality: ISO 26262 & ASIL

Software Engineers love "Move Fast and Break Things." ISO 26262 says: "If you break things, you go to jail."

ASIL Ratings (The "Panic" Metric)

• QM (Quality Managed): The radio. If it crashes, user is annoyed. -> Agile is fine.
• ASIL-B: The Dashboard. If it freezes, user is confused. -> Rigorous Testing.
• ASIL-D: The Brakes. If it fails, user dies. -> Formal Methods. Zero Trust.

[!CAUTION] The Integration Lie: Vendors will sell you "ASIL-D Certified Linux". There is no such thing. The process is certified, not the binary. You still own the liability.

Execution Evidence

Decision Matrix: The Zone Architecture

Moving from 100 ECUs to 3 Zone Controllers.

Interactive Analysis: The "Make vs Buy" for OS