The Plus Safety Case Framework (SCF) presents a structured argument to support the claim that Plus ADS is engineered to meet best practice standards for public road deployment.  The argumentation is a hierarchical structure of claims and supporting claims over several levels.  Each level contributes to the narrative providing core pillars, key arguments, argument efficacy, and detailed claims.  At the foundation of the structure are a series of evidences to support each detailed claim.  

The Plus SCF structure is built upon five pillars that cover the development lifecycle of the Plus ADS - Understand, Design, Develop, Prove and Deploy.  

• The Understand pillar presents Plus’ use of structured process and analysis to ensure quality and completeness. 

• The Design pillar demonstrates how safety and performance attributes are engineered into the design of the Plus ADS. 

• The Develop pillar details the robust test and validation methodology. Testing is conducted at numerous levels from simulation to test bench to vehicle testing on closed course and public road environments.

• The Prove pillar outlines the processes around data driven continuous improvement. The stages of data collection, processing, curation and the derivation of training data and performance metrics are included.

• The Deploy pillar confirms the proficient management of Plus software releases, development and production programs. 
  

The supporting evidences are quantifiable metrics, plans, reports and other methods for presenting the safety performance relevant attributes.  Individual evidences often support a number of detailed claims.  Each evidence has an assigned stakeholder, status and traceability.