» Software in Tractors: Aspects of Development, Maintenance and Support «

Transcription

1 Session: Information Technology for Agricultural Machines» Software in Tractors: Aspects of Development, Maintenance and Support «Dipl.-Ing. Rainer Hofmann, AGCO GmbH, Germany

2 Development of Software is like building a Cathedral

3 Structure (1) General aspects of software engineering (in agricultural machines) (2) Software applications in tractors an overview (3) Economical requirements for software (4) Software development process (5) Maintenance of software (6) Software as a product (7) Integration across manufactures ISOBUS and other standards (8) Conclusions

4 1) General aspects of software engineering in tractors Software controls all vital functions of agricultural machines Technical innovation is driven by software Software is key and core competence in agricultural machinery companies Manufacturers intellectual property in software engineering is a key factor Quality of software defines the quality of a machine Tractors and other agricultural machines are safety critical systems Time, cost and quality have to be balanced >> Software can be easily and quickly modified << Software engineering is defined by its validation process Software does not create parts cost Software is a product in general

5 2) Software applications in tractors Areas of software applications in tractors 1. Basic (tractor) control functions 2. Human machine interface (HMI) 3. Automatic functions 4. Data management 5. Service and support

6 2) Software applications in tractors Basic control functions (tractor) Engine Transmission Hydraulic spool valves and power lift Power train (4-WD, diff.lock) PTO Steering Brake systems Electrics (lighting, washer, ) HVAC Optimisation of mechanical functions: Efficiency = Load sensing Ease of operation Flexibility of production Supervision to reduce wear and prevent damage Diagnostic and calibration

7 2) Software applications in tractors Human-Machine Machine-Interface (HMI) Dashboard Graphical display systems (terminal) Operator panels (armrest) Multifunction levers Warning and error indication External or remote operation Identification of driver to a machine Ergonomic and intuitive operation Driver focus on main or critical function Simple operation / easy to learn option for manual optimisation of tractor functions via menu setups

8 2) Software applications in tractors Automatic Functions Engine transmission management Headland management (automatic operation sequence) Automatic steering via GPS / camera / sensors Implement process control Precision farming process control Optimisation for unskilled drivers Driver focus on main or critical function Intuitive and context sensitive operation of parallel processes

9 2) Software applications in tractors Data acquisition and logging Machine (load, condition, performance, position..) Agricultural working process Driver and labour hours (chemical) substances and material flow Office Software Documentation / Plant Production Precision Farming Fleet management Accounting Data Management Legal requirements for traceability of food production Economic traceability and optimisation Driver is not owner of the process

10 2) Software applications in tractors Service and Support Diagnostic systems (off board) Flash download and parameterize the system at assembly line Field programming systems for software and parameter update Reduce downtime and costs for service Tracking of machine during life cycle Increase flexibility in production Logistic handling of software as a ( mechanical ) part Prevent manipulation e.g. speed control, engine power

11 2) Software applications in tractors Electronic architecture of a top end standard tractor

12 2) Software applications in tractors Complexity Network 4 (CAN) Busses 20 ECUs Software per ECU Multifunction armrest: Dashboard: Main tractor-ecu: Vario-Terminal: Terminal with Linux OS: > 90 % C-Code; 50 % Development by OEM 50% Development by suppliers lines of code (50 files) lines of code (94 files) lines of code(230 files) lines of code lines of code (OS) and lines of code (application)

13 3) Economical requirements for software design Challenges for software design Low volumes of components Differentiation of products Short life cycles of electronic hardware components: μ-processor, memory, Long life cycle of machines in production: years and of spare parts: years Safety critical system: hazards as machine operation and in public road traffic Security against manipulation: e.g. speed control or engine power Costs of hardware decrease in time compared to performance, but add to each tractor Reusability of software is an economic must

14 3) Economical requirements for software design Strategies and Solutions Hardware independence Increasing number of software modules per microprocessor Integration of software modules from (different) suppliers in an (any) ECU Network topology Real-Time operating system Generic software modules Generic communication protocols inside microprocessor units = Virtual bus system and on bus networks (CAN) Definite and detailed software design and verification processes Software version control system

15 3) Economical requirements for software design ECU software architecture ECU Real-Time Operating system Application Software 1 Application Software 2 Internal virtual bus system (GD) Application Software n External bus system (CAN,..) Basic Software: I/O Interface Network communication management (CAN, ) Core Software Microcontroller Hardware Microcontroller

16 3) Economical requirements for software design Interchangeability of software modules ECU C Module Module ECU B Basic Software Module Module Module Core Software Microcontroller Hardware Microcontroller Basic Software Module Core Software Microcontroller Hardware Microcontroller Module Module ECU A Basic Software External bus system (CAN,..) Core Software Microcontroller Hardware Microcontroller

17 4) Software development process V-Model: design and validation cycle - Tractor function Requirements Definition Vehicle Testing - Field test - Fleet test - Hardware - Software architecture - Network topology Basic Design System Testing (HIL, Network) - Test bench - Tractor integration - Network integration - Module - Control algorithm - Simulation Specific Design Integration Test (ECU) - Debugger - Code tester - Simulation - C-coding - Code generation Component Implementation Component Test

18 4) Software development process Quality Management of Software: Design Requirements Definition Basic Design Specific Design Risk analysis Functional specification FMEA Software specification Network and communication layout Manual code generation Simulation, rapid prototyping and C-code generator Component Implementation

19 4) Software development process Quality Management of Software: Validation Diversification of test methods and persons: Modul level - manual and automatic test: Debugger, Emulator, Hardware-in-the loop: simulation and stimulation Automatic code test tools Integration level in tractor: Validation of functionality Validation of FMEA Field test Fleet test Component Test Integration Test (ECU) Vehicle Testing System Testing (HiL, Network)»Does a modification of 1 line of code require the full test cycle?«

20 5) Maintenance of software Maxim of software updates Update of one module has to be consistent to any other module in any other ECU in the network of a tractor for the whole life cycle!

21 5) Maintenance of software - update process Software version control for ECU update Hardware - ID Hardware - ID Bootloader Flash - ID Bootloader Flash - ID Applikationssoftware ID Applikationssoftware ID Applikationssoftware - 2 ID Applikationssoftware - 2 ID Applikationssoftware - n - ID Applikationssoftware - n - ID Parametersatz - ID Parametersatz - ID Hardware - ID Bootloader Flash - ID Applikationssoftware ID Applikationssoftware - 2 ID Applikationssoftware - n - ID Parametersatz - ID Hardware - ID Bootloader Flash - ID Applikationssoftware ID Applikationssoftware - 2 ID Applikationssoftware - n - ID Parametersatz - ID Hardware - ID Bootloader Flash - ID Applikationssoftware ID Applikationssoftware - 2 ID Applikationssoftware - n - ID Parametersatz - ID Identification of hard- and software of each ECU and each module in a tractor

22 5) Maintenance of software - update process Software update Data base contains all relevant software modules Label is defined as a tested combination of soft- und hardware-versions Update means flashing all modules and ECUs to achieve a higher or lower level Update of a single ECU or module is not possible

23 6) Software is a product in general Modular architecture in software und communication (generic protocol) Identification and registration of individual software equipment of a customer tractor Commercial release process for a software update on dealer level Protection against copy Organisation, administration and logistic processes

24 7) Integration across manufacturers - ISOBUS Standards, the way to handle complex electronic structures: the automotive approach: the agricultural machinery approach: ISOBUS ISO AUTomotive Open System ARchitecture

25 7) Integration across manufacturers - ISOBUS Manufacturer.. Manufacturer C Manufacturer B Manufacturer A Manufacturer.. Manufacturer C Manufacturer B Manufacturer A Manufacturer.. Manufacturer C Manufacturer B Manufacturer A Manufacturer.. Manufacturer C Manufacturer B Manufacturer A Manufacturer.. Manufacturer C Manufacturer B Manufacturer A Manufacturer.. Manufacturer C Manufacturer B Manufacturer A

26 7) Integration across manufacturers - ISOBUS An approach for further manufacturer integration Anwender-Plattform ISOBUS e.v. Membership for manufacturers, associations, suppliers, test institutes Platform for electronic engineering Coordination of industrial introduction of electronic standards Development of test tools and test scenarios and documentation (data base) Organisation and performance of workshops, plugfests and certification tests Coordination of technical enhancements Training

27 8) Conclusions Growing increase of Functionality of software: Automatic control of machines and processes Field robotic Complexity of software: Number of modules and their interdependencies Integration of machine networks and data linkage to office software Engineering efforts and expenses: for design and development of software for test and validation of software for administration and support of software in production und service

28 8) Conclusions possible approaches Think in processes Improve methods for absolute encapsulation of software modules Functional safety : improve robustness of software Extension of standards e.g. ISOBUS (ISO 11783) Establish models and platforms for software development processes between manufacturers Establish economic platforms for software cooperation between OEM and suppliers Open source systems or at least open architecture