1. Exploring Variation Mechanisms
in the
Automotive Industry

2. Introduction
 Today car manufacturers produce large no. of Customized
Cars to meet customer demands & to support after market
services.
 But it is impossible to anticipate all configuration at
design time.
 Therefore they focus their attention to “Software Product
Line Method” rather than production line method

3. Software Production Line Method
 Focus on the methods & tools required to create similar
product based on a collection of software assets.
 Objectives:
 Increase the ability to re use software
 To meet customization requirements
 Vital Aspect:
“Variability Management”
The combination of assets to form a single, possibly, unique
product

4.  Variant Handling:
Ability to modify a system without making a big impact on
the system or imposing a need to restructure the design.
Eg:
Inside Lighting System depend on the installed doors
in the car.

5.  Variability:
Is defined in the architecture through variation points, or a
specific place in the architecture at which a feature can
take one of two or more shapes.
 Variability Sources:
 In Function
 In Data
 In Technology
 In Control Flow
 In Environment
 In Quality

6. 4 Variation Patterns
Pattern E.g. of Mechanism Binding Time Usage
Product Configuration Pre-build Implementation during
Architecture management, the architecture &
Derivation Generators design phase
Compilation Compiler Switches Pre-build Compiler flags will
resolve to one binary
output
Linking Binary Replacement Pre-build Linkage with library/
binaries to produce
one binary output
Runtime Adoption during start up Post-build Uses inline code to
condition on variable resolve variability at
runtime.

7. AUTOmotive Open System
ARchitecture (AUTOSAR)
 An open & standardized architecture for the automotive
industry.
 Jointly developed by the largest companies within the
industry together with 3rd party suppliers & tool
developers.
 Aim to improve the way electronic equipment is
developed, increase safety, performance & environmental
friendliness.

8.  Modules introduce in the standard
 UML Meta Models
 Annotated Meta Model
 Extended Meta Model
 4 patterns describe in the standard,
 Aggregation Value Standard
 Association Value Standard
 Attribute Value Standard
 Property Set Value Standard

9. What is a Quality Tree??
 Way of assessing & categorizing variant patterns used in
an organization.
 Leaf nodes represent strength &weaknesses discovered
during the implementation.
 Provide,
 Guidance for the architect when making decisions for how
to manage variability.
 Good overview of the characteristics of one specific
pattern.

10. Mainly Focus
Focus on key elements required to
support run time variability using the
AUTOSAR 4 .0 Standard through
developing a prototype.

11. Research Method
There are 3 subsections,
 Case setting
 Data source.
 Process

12. Case Setting
 Problem based on the Volvo Car’s preconceptions for
managing variability to implement a variant mechanisms
for run – time variability.
 There are three stages in development that variants are
used today at Volvo Cars. They are,
 compilation mechanisms
 local parameterization
 distributed parameterization.

13. Data Sources
Sources Type Advantages Limitations
Volvo cars Document, architecture Valuable information Restricted by
component specification based on refined confidentiality
specification domain knowledge. agreement.
Primary
Sources Volvo cars Document Valuable information Draft document,
run-time ,architecture based on refined may change.
variability specification domain knowledge. Restructured by
specification confidentiality
agreement.
Software Regular discussions 10 year of hand- on Data is
architect at architect experience interpreted twice.
Volvo cars at Volvo cars
Secondary AUTOSAR Documents and UML Publicly available. Difficult to
Sources 4.0 meta-models Thorough and with address all
specification examples. relevant sections.

14. Process
Under this step we can divided the implementation into
three phases.
 C Implementation - Written entirely in C
 CAN-bus Implementation - Written entirely in C
 AUTOSAR Implementation - Developed using
AUTOSAR complaint tools.

15. To assess the specification provided by Volvo cars.
 First phase-:
Intentionally avoided any use of “AUTOSAR”. Consequently this made it possible
to discover what was required of the variant before making the prototype more true
to the automotive environment.
 Second phase-:
Findings from the first phase were used to further refine the implementation towards
the automotive industry.
 Third phase-:
Based on the findings with some limitations from the previous phases.
The company started the development based on the following premises and
requirements.
 As much as possible takes place run-time.
 A solution must be independent from the data it is supposed to pass.
 Data used by a services does not have to be stored on the ECU where the service running.

16. Research Data
 The results outlined in this slides are coming from a
prototype implementation of a run – time variability
pattern.
 Publisher-subscriber which is a mechanism for
components, during application execution, to subscribe to
state updates generated by another component, the so
called publisher.
 Volvo Cars' specification in its current state does not
require subscription to take place in run-time.

17. Implementation
Phases

18. Phase 1: C Implementation

19. Phase 2: CAN-bus Implementation

20. Phase 3: AUTOSAR Implementation

21. Quality Scenarios learnt during
Implementation

22.  Highlighted aspects derived during the
development:
 Subscription
 Multiple Publishers
 Push & Pull Strategies
 Register Parameters of Interest
 Local & Global configuration files
 Parameters in an AUTOSAR environment

23. Analysis
 Quality Tree

24. Automotive Industry
 Following factors have introduced for the motivation of
variability in AUTOSAR.
 Establish a common language to enable suppliers and
manufactures to work together.
 Use to avoid redundancy between artifacts.
 It provides a basis for basic software product line.