Conventional development approaches for safety-critical software (the process chain depicted at top in the illustration) allow for testing of software behavior, functionality, and reliability only after a system has been integrated in a vehicle.

With model-based development (the process chain shown at the bottom), the functionality of a safety-critical application can be tested at a very early stage of the product creation process — i.e. in the planning phase, long before a vehicle prototype has been built. The testing methods used here deliver much more robust results than the most comprehensive empirical tests, and they make statements like the following valid: “The control unit software in Active Brake Assist will never initiate a partial or complete emergency braking maneuver in a safe driving situation.”