AUTOSAR
Encyclopedia
AUTOSAR is an open and standardized automotive software
architecture, jointly developed by automobile manufacturers, suppliers and tool developers. It is a partnership of automotive OEMs, suppliers and tool vendors whose objective is to create and establish open standards for automotive E/E (Electrics/Electronics) architectures that will provide a basic infrastructure
to assist with developing vehicular software, user interfaces and management for all application domain
s. This includes the standardization of basic systems functions, scalability
to different vehicle
and platform variants, transferability
throughout the network, integration
from multiple suppliers, maintainability
throughout the entire product life-cycle and software update
s and upgrades over the vehicle's lifetime as some of the key goals.
AUTOSAR has been devised to:
As stated in the official website, the goals of AUTOSAR are:
The above mentioned goals are pursued by choosing a software architecture that supports a design model based on component based design. The model is supported by an automated methodology to create the software executable for the ECUs
, starting from the design model and the properties and physical topology of the hardware.
This way the Autosar-projects tries to create a paradigm shift in automotive software development from an ECU based approach to a function based approach.
The application software components are the smallest pieces of application software that still have a certain functionality. The software of an application can then be composed by using different application software-components.
Standardized interfaces for all the application software components necessary to build the different automotive applications are specified in the AUTOSAR-standards. By only defining the interfaces, there is still freedom in the way of obtaining the functionality.
The virtual function bus connects the different software components in the design model. This abstract component interconnects the different application software components and handles the information exchange between them. The virtual function bus is the conceptualization of all hardware and system services offered by the vehicular system. This makes it possible for the designers to focus on the application instead of the infrastructure software.
By using the virtual function bus, the application software components do not need to know with which other application software components they communicate. The software components give their output to the virtual function bus, which guides the information to the input ports of the software components that need that information. This is possible due to the standardized interfaces of the software components which specifies the input and output ports as well as the format of data exchange.
This approach makes it possible to validate the interaction of all components and interfaces before software implementation. This is also a fast way to make changes in the system design and check whether the system will still function.
The Basic Software and Runtime Environment are the technical realization of the virtual function bus in the design model.
The layered architecture is used on every ECU and makes it possible to design a vehicle system without thinking in terms of ECUs. The designers select a number of software components that do not know on which ECU certain software components are installed or hardware is connected. The Runtime Environment makes sure that the software components can communicate with one another or with the hardware, without concern if both components are on different ECUs or not.
This methodology is automated by using tool-chains. All subsequent methodology steps up to the generation of executables are supported by defining exchange formats (using XML) and work methods for each step.
To support the Autosar-methodology, a meta-model
is developed. This is a formal description of all methodology related information, modeled in UML.
This leads to the following benefits:
Core membership only is available for leading car manufacturers and Tier1; the other types of membership are open to other companies as well.
Core members include the PSA Peugeot Citroën
, Toyota Motor Corporation, Volkswagen
, BMW
Group, Daimler AG, Ford Motor Company, Opel
, and automotive suppliers Bosch
, Continental AG
and Siemens VDO
(now Continental AG).
There are a total of 35 corporate members as of September 2005.
The professed goals are modularity
, scalability
, transferability and re-usability of functions to provide a standardized platform for automotive systems. This will enable system wide configuration
and optimization to meet run-time requirements of automotive devices. Many of the low-level components of AUTOSAR (the real time operating system and communications layer) are derived from OSEK
work.
Based on these ideas a meta-model to capture high-level requirements and an implementation to calculate the corresponding latencies on system-level was developed.
Although a meta-model to capture high-level requirements can aid in the development of vehicular systems, there still can be problems to find timing-issues like buffer-overflow or missed deadlines. This is due to non-functional time-delays (e.g., buffering of signals, allocation of memory).
These are problems that the OEMs will have to solve during the implementation of the entire system.
For complex ECUs the situation is different. Here the availability of a common core definition allows efficient re-use of basic functions by application software.
Automotive software
Automotive software refers to any software, , related to automotive industry specific products or services.- See also :* Microsoft Auto* Infotainment* Telematics* *...
architecture, jointly developed by automobile manufacturers, suppliers and tool developers. It is a partnership of automotive OEMs, suppliers and tool vendors whose objective is to create and establish open standards for automotive E/E (Electrics/Electronics) architectures that will provide a basic infrastructure
Infrastructure
Infrastructure is basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function...
to assist with developing vehicular software, user interfaces and management for all application domain
Application domain
In Microsoft's Common Language Runtime , an application domain is a mechanism used to isolate executed software applications from one another so that they do not affect each other...
s. This includes the standardization of basic systems functions, scalability
Scalability
In electronics scalability is the ability of a system, network, or process, to handle growing amount of work in a graceful manner or its ability to be enlarged to accommodate that growth...
to different vehicle
Vehicle
A vehicle is a device that is designed or used to transport people or cargo. Most often vehicles are manufactured, such as bicycles, cars, motorcycles, trains, ships, boats, and aircraft....
and platform variants, transferability
Transferability
This page is about transferability in chemistry. Transferability in economics also exists.Transferability, in chemistry, is the assumption that a chemical property that is associated with an atom or a functional group in a molecule will have a similar value in a variety of different circumstances...
throughout the network, integration
System integration
In engineering, system integration is the bringing together of the component subsystems into one system and ensuring that the subsystems function together as a system...
from multiple suppliers, maintainability
Maintainability
In engineering, maintainability is the ease with which a product can be maintained in order to:* isolate defects or their cause* correct defects or their cause* meet new requirements* make future maintenance easier, or* cope with a changed environment...
throughout the entire product life-cycle and software update
Software Update
Software Update is a software tool by Apple Inc. that installs the latest version of Apple software on computers running Mac OS X. It was originally introduced to Mac users in Mac OS 9. A Windows version has been available since the introduction of iTunes 7, under the name Apple Software Update....
s and upgrades over the vehicle's lifetime as some of the key goals.
AUTOSAR has been devised to:
- Pave the way for innovative electronic systemsElectronic SystemsElectronic systems are groupings of electronic circuits and components which are designed to accomplish one or more complex functions. Examples include telecommunication systems, computer systems, power distribution systems, radar systems, electronic music systems, and many others.Electronic...
that further improve performance, safety and environmentalNatural environmentThe natural environment encompasses all living and non-living things occurring naturally on Earth or some region thereof. It is an environment that encompasses the interaction of all living species....
friendliness - Be a strong global partnership that creates one common standard: "Cooperate on standards, compete on implementationImplementationImplementation is the realization of an application, or execution of a plan, idea, model, design, specification, standard, algorithm, or policy.-Computer Science:...
" - Be a key enabling technologyTechnologyTechnology is the making, usage, and knowledge of tools, machines, techniques, crafts, systems or methods of organization in order to solve a problem or perform a specific function. It can also refer to the collection of such tools, machinery, and procedures. The word technology comes ;...
to manage the growing electrics/electronics complexity. It aims to be prepared for the upcoming technologies and to improve cost-efficiencyCost EfficiencyCost efficiency , in the context of parallel computer algorithms, refers to a measure of how effectively parallel computing can be used to solve a particular problem...
without making any compromise with respect to quality - Facilitate the exchange and update of software and hardwareHardwareHardware is a general term for equipment such as keys, locks, hinges, latches, handles, wire, chains, plumbing supplies, tools, utensils, cutlery and machine parts. Household hardware is typically sold in hardware stores....
over the service life of the vehicle
As stated in the official website, the goals of AUTOSAR are:
- Implementation and standardization of basic system functions as an OEM wide "Standard Core" solution
- Scalability to different vehicle and platform variants
- Transferability of functions throughout network
- Integration of functional modules from multiple suppliers
- Consideration of availability and safety requirements
- Redundancy activation
- Maintainability throughout the whole "Product Life Cycle"
- Increased use of "Commercial off the shelf hardware"
- Software updates and upgrades over vehicle lifetime
The above mentioned goals are pursued by choosing a software architecture that supports a design model based on component based design. The model is supported by an automated methodology to create the software executable for the ECUs
Electronic control unit
In automotive electronics, electronic control unit is a generic term for any embedded system that controls one or more of the electrical systems or subsystems in a motor vehicle....
, starting from the design model and the properties and physical topology of the hardware.
This way the Autosar-projects tries to create a paradigm shift in automotive software development from an ECU based approach to a function based approach.
Design model
The AUTOSAR-standard enables the use of a component based software design model for the design of a vehicular system. The design model uses application software components which are linked through an abstract component, named the virtual function bus.The application software components are the smallest pieces of application software that still have a certain functionality. The software of an application can then be composed by using different application software-components.
Standardized interfaces for all the application software components necessary to build the different automotive applications are specified in the AUTOSAR-standards. By only defining the interfaces, there is still freedom in the way of obtaining the functionality.
The virtual function bus connects the different software components in the design model. This abstract component interconnects the different application software components and handles the information exchange between them. The virtual function bus is the conceptualization of all hardware and system services offered by the vehicular system. This makes it possible for the designers to focus on the application instead of the infrastructure software.
By using the virtual function bus, the application software components do not need to know with which other application software components they communicate. The software components give their output to the virtual function bus, which guides the information to the input ports of the software components that need that information. This is possible due to the standardized interfaces of the software components which specifies the input and output ports as well as the format of data exchange.
This approach makes it possible to validate the interaction of all components and interfaces before software implementation. This is also a fast way to make changes in the system design and check whether the system will still function.
Software architecture
To make a component based design possible, the AUTOSAR-project uses a layered architecture that ensures the decoupling of the functionality from the supporting hardware and software services.- Basic Software Layer: the Basic Software is standardized software that does not have any functionality but offers hardware-dependent and hardware-independent services to the layer above (the Run Time Environment). This is realized through the use of Application Programming InterfaceApplication programming interfaceAn application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...
s. This layer itself is not entirely hardware independent but makes the upper layers hardware independent.
- Runtime environment: handles the information exchange between the application software components and connects the application software components to the right hardware. This layer decouples the application software components from the hardware as well as the application software components from themselves.
- Application Layer: the application layer is the only layer that is not composed of standardized software, it is also the layer where the actual functionality is situated. The layer is composed of application software components that interact with the run time environment.
The Basic Software and Runtime Environment are the technical realization of the virtual function bus in the design model.
The layered architecture is used on every ECU and makes it possible to design a vehicle system without thinking in terms of ECUs. The designers select a number of software components that do not know on which ECU certain software components are installed or hardware is connected. The Runtime Environment makes sure that the software components can communicate with one another or with the hardware, without concern if both components are on different ECUs or not.
Methodology
The AUTOSAR-project created a methodology that can be used to create the E/E system architecture starting from the design-model. This approach uses 4 steps:Step 1: Input Descriptions
The input description step contains three descriptions:- Software Components: This description is independent of the actual implementation of the software component. Among the necessary data to be specified are the interfaces and the hardware requirements.
- System: The system topology (interconnections between ECUs) need to be specified together with the available data busses, used protocols, function clustering and communication matrix and attributes (e.g. data rates, timing/latency, …).
- Hardware: The available hardware (processors, sensors, actuators, …) needs to be specified together with the signal processing methods and programming capabilities
Step 2: System Configuration
This step distributes the software component descriptions to the different ECU. This is an iterative process where ECU-resources and system-constraints are taken into account. For example, there needs to be checked whether the necessary communication-speeds are met.Step 3: ECU-configuration
In this step, the Basic Software and the Run Time Environment of each ECU is configured. This is based on the dedication of the application software components to each ECU.Step 4: Generation of Software Executables
Based on the configuration of the previous step, the software executables are generated. For this step, it’s necessary to specify the implementation of each software component.This methodology is automated by using tool-chains. All subsequent methodology steps up to the generation of executables are supported by defining exchange formats (using XML) and work methods for each step.
To support the Autosar-methodology, a meta-model
Meta-Object Facility
The Meta-Object Facility is an Object Management Group standard for model-driven engineering. The official reference page may be found at OMG's website.- Overview :...
is developed. This is a formal description of all methodology related information, modeled in UML.
This leads to the following benefits:
- The structure of the information can be clearly visualized
- The consistency of the information is guaranteed
- Using XML, a data exchange format can be generated automatically out of the meta-model and be used as input for the methodology.
- Easy maintenance of the entire vehicular system
Members
There are four types of membership for AUTOSAR:- Core (founding) members
- Premium members
- Associate members
- Development members
Core membership only is available for leading car manufacturers and Tier1; the other types of membership are open to other companies as well.
Core members include the PSA Peugeot Citroën
PSA Peugeot Citroën
PSA Peugeot Citroën is a French manufacturer of automobiles and motorcycles sold under the Peugeot and Citroën marques. Headquartered in the 16th arrondissement of Paris, PSA is the second largest automaker based in Europe and the number eight in the world.-History:In December 1974 Peugeot S.A....
, Toyota Motor Corporation, Volkswagen
Volkswagen
Volkswagen is a German automobile manufacturer and is the original and biggest-selling marque of the Volkswagen Group, which now also owns the Audi, Bentley, Bugatti, Lamborghini, SEAT, and Škoda marques and the truck manufacturer Scania.Volkswagen means "people's car" in German, where it is...
, BMW
BMW
Bayerische Motoren Werke AG is a German automobile, motorcycle and engine manufacturing company founded in 1916. It also owns and produces the Mini marque, and is the parent company of Rolls-Royce Motor Cars. BMW produces motorcycles under BMW Motorrad and Husqvarna brands...
Group, Daimler AG, Ford Motor Company, Opel
Opel
Adam Opel AG, generally shortened to Opel, is a German automobile company founded by Adam Opel in 1862. Opel has been building automobiles since 1899, and became an Aktiengesellschaft in 1929...
, and automotive suppliers Bosch
Robert Bosch GmbH
Robert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
, Continental AG
Continental AG
Continental AG, internally often called Conti for short, is a worldwide leading German manufacturer of tires, brake systems, vehicle stability control systems, engine injection systems, tachographs and other parts for the automotive and transport industries. The company is based in Hanover, Germany...
and Siemens VDO
Siemens VDO
VDO , is a manufacturer of information and cockpit systems, navigation, telematics, communication and audio systems, and control and fuel systems....
(now Continental AG).
There are a total of 35 corporate members as of September 2005.
The professed goals are modularity
Modularity
Modularity is a general systems concept, typically defined as a continuum describing the degree to which a system’s components may be separated and recombined. It refers to both the tightness of coupling between components, and the degree to which the “rules” of the system architecture enable the...
, scalability
Scalability
In electronics scalability is the ability of a system, network, or process, to handle growing amount of work in a graceful manner or its ability to be enlarged to accommodate that growth...
, transferability and re-usability of functions to provide a standardized platform for automotive systems. This will enable system wide configuration
Configuration
The term configuration has several meanings.In computing it may refer to:* Computer configuration or system configuration* Configure is the output of Autotools and used to detect system configuration...
and optimization to meet run-time requirements of automotive devices. Many of the low-level components of AUTOSAR (the real time operating system and communications layer) are derived from OSEK
OSEK
OSEK is a standards body that has produced specifications for an embedded operating system, a communications stack, and a network management protocol for automotive embedded systems...
work.
Implementers
According to the AUTOSAR-paradigm "Common standard, concurring implementations", several software suppliers offer software implementations of the AUTOSAR standard. Some of the suppliers of AUTOSAR standard software are:- ArcCore - (Arctic Core - open source AUTOSAR).
- BoschRobert Bosch GmbHRobert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
(CUBAS) - BoschRobert Bosch GmbHRobert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...
(iSolar) - Continental Engineering Services - (CES , AUTOSAR Center)
- dSPACE (SystemDesk, TargetLink)
- EB / ElektrobitElektrobitElektrobit Corporation is a Finnish company headquartered in Oulu.Elektrobit, EB is an engineering company in Wireless and Automotive businesses...
(EB tresos AutoCore) - ETASETAS GroupThe ETAS Group designs and markets development and diagnostic tools essential to both development and service of automotive electronic control units .- Business :...
(ASCET, INCA, INTECRIO, RTA) - EXITE ACE VFB(http://www.extessy.com)
- Freescale (Freescale AUTOSAR Software)
- Geensoft AUTOSAR Builder
- KPIT Cummins Infosystems LimitedKPIT CumminsKPIT Cummins is a product engineering and IT consulting company providing solutions and services to the Manufacturing, Automotive, Industrial Equipments, Utilities and Semiconductor companies. It is headquartered in Pune India and has offices in 11 countries including the United Kingdom, China,...
- MathWorks (Simulink/Stateflow/Embedded Coder)
- MecelMecelMecel Mecel is a software and systems consulting firm, specializing in the automotive industry. The company has offices in Gothenburg and has approximately 120 employees.- History :...
(Mecel Picea) - Mentor Graphics (Mentor Graphics VSx Platform)
- NECNEC, a Japanese multinational IT company, has its headquarters in Minato, Tokyo, Japan. NEC, part of the Sumitomo Group, provides information technology and network solutions to business enterprises, communications services providers and government....
Electronics (NEC AUTOSAR MCAL for V850V850The Renesas Electronics V850 is a 32-bit RISC CPU core architecture for embedded microcontrollers originally developed and manufactured by NEC, succeeded by V850 variants named V850ES, V850E, and V850E2 which run uClinux. Compilers available for it include the GNU Compiler Collection, IAR Systems...
platform) - OpenSynergy(http://www.opensynergy.com)
- pulse-AR Tool
- Renesas ElectronicsRenesas Electronicsis a Japanese semiconductor manufacturer. It is based in Tokyo and has manufacturing, design and sales operations in around 20 countries. Renesas is one of the world's largest manufacturers of semiconductor systems for mobile phones and automotive applications. It is the world's largest...
- (Renesas Electronics MCAL AUTOSAR package) - SYSGOSYSGOSYSGO AG is a German company oriented in embedded software since its founding in 1991. The company is focused on the basic software building blocks for embedded systems used in critical environments such as airplanes, medical instruments or industrial automation...
(PikeOSPikeOSPikeOS is a microkernel-based real-time operating system made by SYSGO AG. It is targeted at safety and security critical embedded systems. It provides a partitioned environment for multiple operating systems with different design goals, safety requirements, or security requirements to coexist in a...
RTOS) - Tata ElxsiTata elxsi- Introduction : is a technology-led design services company and part of the $70 billion Tata Group. Headquartered in Bangalore and with a global delivery footprint through offices and centers in India, the US, the UK, Japan and Germany, Tata Elxsi is a company focused on delivering outsourced...
(http://www.tataelxsi.com/htmls/pds/pds_autosar.htm) - Time Partition Testing - model based testing of AUTOSAR components. cf. PikeTec
- Vector Informatik GmbHVector InformatikVector Informatik develops software tools and components for networking of electronic systems based on the serial bus systems CAN, LIN, FlexRay, MOST, Ethernet and SAE J1708 as well as on CAN-based protocols such as SAE J1939, SAE J1587, ISO 11783, NMEA 2000, ARINC 825, CANaerospace, CANopen and...
Timing
AUTOSAR lacks information about timing requirements in its meta-model. On the one hand there are high-level requirements like end-to-end latencies that specify temporal behaviour of the system on the logical abstraction of system functions. On the other hand there exist timing relevant implementation details of the system-level.Based on these ideas a meta-model to capture high-level requirements and an implementation to calculate the corresponding latencies on system-level was developed.
Although a meta-model to capture high-level requirements can aid in the development of vehicular systems, there still can be problems to find timing-issues like buffer-overflow or missed deadlines. This is due to non-functional time-delays (e.g., buffering of signals, allocation of memory).
These are problems that the OEMs will have to solve during the implementation of the entire system.
Efficiency
Tailored-fit systems can be designed to be more efficient than software built from ‘plug-and-play’ software components. Hence small systems designed according to the AUTOSAR standard need more memory and more computing power. The extra cost of the ECU resources is a major issue in the highly cost-driven automotive business.For complex ECUs the situation is different. Here the availability of a common core definition allows efficient re-use of basic functions by application software.
Too much standard
During the standard creation process, many participants – OEMs as well as tier-one companies – lobbied and managed to get functions and elements established as a part of the standard that not all the members of the Autosar consortium were interested in. This bloats the standard’s definition at the expense of clarity. The consequence will be that many suppliers offer different subsets of the standard definitionFurther reading
External links
- Official website
- Chip vendors facing up to AUTOSAR challenge in AutomotivedDesign Europe
- AUTOSAR Group on Xing
- About AUTOSAR AUTOSAR auf der Renesas Homepage