（注：本文是譯文，Original author: Eckard Bringmann)

In recent years the development of automotive embedded devices has changed from an electrical and mechanical engineering discipline to a combination of software and electrical/mechanical engineering. The effects of this change on development processes, methods, and tools as well as on required engineering skills were very significant and are still ongoing today.
近年來(lái)，汽車嵌入式設(shè)備的發(fā)展已經(jīng)改變了電氣和機(jī)械工程學(xué)科相結(jié)合的軟件和電氣/機(jī)械工程。這一變化對(duì)今天開(kāi)發(fā)流程、方法和工具以及所需的工程技能是非常重要的。

At present there is a new trend in the automotive industry towards model-based development. Software components are no longer handwritten in C or Assembler code but modeled with MATLAB/Simulink™, Statemate, or similar tools.
目前汽車工業(yè)朝著基于模型的方向發(fā)展。軟件組件不再以C或匯編代碼手寫(xiě)，而是用Matlab/Simulink、StimeMe或類似的工具建模。

However, quality assurance of model-based developments, especially testing, is still poorly supported. Many development projects require creation of expensive proprietary testing solutions.
然而，基于模型的發(fā)展，特別是測(cè)試質(zhì)量保證，仍然缺乏支持。許多開(kāi)發(fā)項(xiàng)目需要?jiǎng)?chuàng)造昂貴的專用測(cè)試解決方案。

Reconsider testing procedures in practice. Furthermore, we introduce the test tool “TPT”.
在實(shí)踐中重新考慮測(cè)試程序。此外，我們?cè)谄囶I(lǐng)域引入基于模型的測(cè)試工具TPT” 。

TPT is based on graphical test models that are not only easy to understand but also powerful enough to express very complex, fully automated closed loop tests in real-time. TPT has been initially developed by Daimler Software Technology Research. It is already in use in many production-vehicle development projects at car manufacturers and suppliers.
TPT是基于圖形的測(cè)試模型，不僅容易理解，也足以表達(dá)非常復(fù)雜，完全自動(dòng)化的實(shí)時(shí)閉環(huán)測(cè)試。TPT由戴姆勒軟件技術(shù)研究初步開(kāi)發(fā)，已有許多汽車制造商和供應(yīng)商應(yīng)用到開(kāi)發(fā)的項(xiàng)目中

Motivation
動(dòng)機(jī)
Within only a few years the share of software controlled innovations in the automotive industry has increased from 20 percent to 80 percent, and is still growing. Forecasts claim that software will determine more than 90% of the functionality of automotive systems within the next decade. Consequently the impact of software on the customer and hence on market shares and competition will be enormous.
僅僅在幾年內(nèi)軟件控制的創(chuàng)新在汽車行業(yè)的份額已經(jīng)從20%增加到80%，并且還在增長(zhǎng)。預(yù)測(cè)認(rèn)為，在接下來(lái)的十年軟件將超過(guò)汽車系統(tǒng)的功能90%。因此，軟件即影響了客戶和汽車在市場(chǎng)的份額和競(jìng)爭(zhēng)力。

During recent years the growth of software in the automotive industry led to a development process founded on model based technologies which have many advantages for automotive developments. Firstly model-based technologies such as MATLAB/Simulink, Statemate, MatrixX, or LabView are domain specific and support powerful mechanisms for handling and processing continuous signals and events which are the most important data types in the automotive domain. These model-based technologies allow the development of high-level models that can be used for simulation in very early stages of the development process. This in turn is important since automotive development is an interdisciplinary business with software, electrical, and mechanical engineering aspects inextricably entwined. Graphical models and simulation of such models allows engineers to find a common functional understanding early in the design phase. So, model-based development improves communication within development teams, with customers, or between car manufacturers and suppliers.
近年來(lái)，軟件在汽車工業(yè)中的發(fā)展導(dǎo)致了基于模型的技術(shù)的開(kāi)發(fā)，該技術(shù)對(duì)于汽車開(kāi)發(fā)具有許多優(yōu)點(diǎn)。首先，基于模型的技術(shù)，如Matlab/Simulink、StimeMaT、MatrixX或LabVIEW是特定于域的，并有支持處理連續(xù)信號(hào)和事件的強(qiáng)大機(jī)制，這些信號(hào)和事件是汽車領(lǐng)域中最重要的數(shù)據(jù)類型。這些基于模型的技術(shù)允許用于開(kāi)發(fā)過(guò)程非常早期階段的仿真高級(jí)模型。這很重要，因?yàn)槠嚢l(fā)展是一個(gè)跨學(xué)科的業(yè)務(wù)與軟件，電氣和機(jī)械工程方面密不可分。圖形模型和仿真這樣的模型允許工程師在設(shè)計(jì)階段早期找到對(duì)功能的共同理解。因此，基于模型的開(kāi)發(fā)改善了開(kāi)發(fā)團(tuán)隊(duì)內(nèi)部與客戶之間的溝通，或者改善了汽車制造商和供應(yīng)商之間的溝通。

It reduces time to market through component re-use and reduces costs by validating systems and software designs up front prior to implementation. Consequently models are often treated as part of the requirements specification, since the models illustrate the required functionality in an executable manner. Model-based development provides a development process from requirements to code, ensuring that the implemented systems are complete and behave as expected. Model-based development allows segregation of concerns; technical aspects such as fixed-point scaling (i.e. the transformation of floating-point algorithms to fixed-point computations), calibration data management, and the representation of signals in memory are separated from the core algorithms thereby keeping the models as lean as possible.
通過(guò)在執(zhí)行之前驗(yàn)證系統(tǒng)和軟件設(shè)計(jì)，減少了通過(guò)組件重用的市場(chǎng)時(shí)間，并降低了成本。因此，模型通常被視為需求規(guī)范的一部分，因?yàn)槟Ｐ鸵钥蓤?zhí)行的方式說(shuō)明所需的功能?；谀Ｐ偷拈_(kāi)發(fā)提供了一個(gè)從需求到代碼的開(kāi)發(fā)過(guò)程，確保實(shí)現(xiàn)的系統(tǒng)是完整并按照預(yù)期的行為?；谀Ｐ偷拈_(kāi)發(fā)允許分別關(guān)注各技術(shù)方面，例如定點(diǎn)縮放（即浮點(diǎn)算法到定點(diǎn)計(jì)算的轉(zhuǎn)換）、校準(zhǔn)數(shù)據(jù)管理和存儲(chǔ)器中信號(hào)的表示與核心算法分開(kāi)。因此，保持模型盡可能精煉。

Model-based testing in practice
基于模型的實(shí)踐檢驗(yàn)
Along with the growing functionality and the introduction of model-based development processes, the demands on quality assurance have also increased. In terms of testing, model-based development enables system engineers to test the system in a virtual environment when they are inexpensive to fix, i.e. before the code is actually implemented or integrated on the final hardware (which is called ECU or electronic control unit). However, in practice there are just a few testing procedures that address the automotive domain-specific requirements of model-based testing sufficiently. The applied test methods and tools are often proprietary, ineffective and require significant effort and money. about 15 years ago testing embedded devices comprised primarily of four well-understood areas: (1) electromagnetic compatibility (EMC tests), (2) electrical tests (e.g. short-circuit, creeping current, stress peaks), (3) environmental tests (i.e. testing under extreme climate conditions), and (4) field tests (on proving ground or the road).
隨著功能的不斷增多及基于模型的開(kāi)發(fā)過(guò)程的引入，對(duì)質(zhì)量保證的需求也增加了。在測(cè)試方面，基于模型的開(kāi)發(fā)使系統(tǒng)工程師能夠在虛擬環(huán)境中對(duì)系統(tǒng)進(jìn)行測(cè)試，即可低成本地糾正錯(cuò)誤，因?yàn)檫@個(gè)糾正發(fā)生在代碼實(shí)際實(shí)現(xiàn)或集成到最終硬件（被稱為ECU或電子控制單元）之前。然而，在實(shí)踐中，只有少數(shù)測(cè)試程序能夠滿足基于模型測(cè)試的汽車領(lǐng)域的特定要求。應(yīng)用的測(cè)試方法和工具通常是專有的，無(wú)效的，需要大量的努力和金錢(qián)。大約15年前測(cè)試嵌入式設(shè)備主要包括四個(gè)領(lǐng)域：（1）電磁兼容性（EMC試驗(yàn)），（2）電氣試驗(yàn)（例如短路、蠕動(dòng)電流、應(yīng)力峰值）、（3）環(huán)境試驗(yàn)（即極端氣候條件下的測(cè)試）和（4）現(xiàn)場(chǎng)試驗(yàn)（試驗(yàn)場(chǎng)或道路）。

Requirements for automotive MBT
汽車MBT要求
The term ‘model-based testing’ is widely used today with slightly different meanings. In the automotive industry it is normally used to describe all testing activities in the context of model-based development projects.
“基于模型的測(cè)試”這個(gè)術(shù)語(yǔ)如今被廣泛使用，意義略有不同。在汽車工業(yè)中，它通常用來(lái)描述在基于模型的開(kāi)發(fā)項(xiàng)目的環(huán)境中的所有測(cè)試活動(dòng)。

Automotive model-based development has specific characteristics that require the use of dedicated model-based testing approaches. The characteristics of, and the resulting requirements for model-based testing are discussed below.
基于汽車模型的開(kāi)發(fā)具有特定的特性，需要使用基于模型的專用測(cè)試方法。下面討論了基于模型的測(cè)試的特性以及由此產(chǎn)生的需求。

Test automation
測(cè)試自動(dòng)化
Automotive systems usually interact with a real-world environment which is under continual control of the embedded system. Thus the whole system is not only a piece of software, but a complex construction that consists of software, hardware, electrical, mechanical, and/or hydraulic parts. The development of such a system requires the co-design of software and hardware components. Consequently an iterative process is needed with a considerable number of interim releases of the integrated system. Thoroughly testing these interim releases is crucial to ensure that requirements inconsistencies and design or implementation faults can be uncovered as early as possible. This means that the same tests have to be repeated again and again over the development cycle. Test automation is therefore essential as the manual test workload over many iterations would be at best expensive and likely not practical, leading to less than thorough quality assurance standards.
汽車系統(tǒng)通常與嵌入式系統(tǒng)持續(xù)控制下的現(xiàn)實(shí)環(huán)境相互作用。因此整個(gè)系統(tǒng)不僅是一個(gè)軟件，而是一個(gè)復(fù)雜的工程，包括軟件、硬件、電氣、機(jī)械和/或液壓件。開(kāi)發(fā)這樣一個(gè)系統(tǒng)需要軟件和硬件組件的協(xié)同設(shè)計(jì)。因此，系統(tǒng)集成需要相當(dāng)多的迭代過(guò)程。徹底測(cè)試這些臨時(shí)版本是保證盡早發(fā)現(xiàn)設(shè)計(jì)要求矛盾或?qū)嵤┕收?。這意味著，在開(kāi)發(fā)周期內(nèi)同樣的測(cè)試必須一遍又一遍的重復(fù)。在多次迭代，手動(dòng)測(cè)試工作量巨大且質(zhì)量難以保證的情況下有必要采用測(cè)試自動(dòng)化。

Systematic test case design
系統(tǒng)測(cè)試設(shè)計(jì)
For many reasons automotive model-based developments usually consist of complex functionality. The systems interact with physical components that have a complex behavior which depends on many variables. Controlling such components also introduces complex controller functionality. Secondly the electrical, mechanical, and hydraulic components can fail and the embedded system has to detect such failures and compensate for them in a very robust way, as far as technically possible. The implementation of code to handle all such failure modes is a significant portion of the system software.
出于許多原因，基于汽車模型的開(kāi)發(fā)通常包括復(fù)雜的功能。系統(tǒng)與具有許多變量相關(guān)的復(fù)雜行為的物理組件交互?？刂七@樣的組件還引入了復(fù)雜的控制器功能。其次，電氣、機(jī)械和液壓元件可能會(huì)失效，并且嵌入式系統(tǒng)必須檢測(cè)這些故障并以非常穩(wěn)健的方式對(duì)它們進(jìn)行補(bǔ)償，實(shí)現(xiàn)所有這樣的故障模式的代碼是系統(tǒng)軟件的重要組成部分。

Readability
可讀性
Automotive model-based testing is a collaborative work between testers, system engineers, and programmers. All of these experts have different perspectives on the system, different skills and experiences, and provide important information for the identification of suitable test cases: system engineers know about the possible pitfalls of the application domain, programmers know about the complexity of algorithms and their risk of faults, and testers know about coverage and combination issues, boundary tests, robustness tests and others methods that have to be considered in the test implementation.
基于汽車模型的測(cè)試是測(cè)試人員、系統(tǒng)工程師和程序員之間的協(xié)作工作。所有這些專家對(duì)系統(tǒng)、不同的技能和經(jīng)驗(yàn)都有不同的觀點(diǎn)，并且為識(shí)別合適的測(cè)試用例提供了重要的信息：系統(tǒng)工程師知道應(yīng)用領(lǐng)域可能的缺陷，程序員知道算法的復(fù)雜性，故障風(fēng)險(xiǎn)，測(cè)試人員知道在測(cè)試實(shí)現(xiàn)中必須考慮的覆蓋和組合問(wèn)題、邊界測(cè)試、健壯性測(cè)試和其他方法。

The principle of model-based development is to use models as a “common language” comprehensible to all engineers involved in the development. Hence model-based testing should be readable and comprehensible by all of these experts too and not just by a few testing specialists.
基于模型的開(kāi)發(fā)原則是使用模型作為一種“通用語(yǔ)言”，讓所有參與開(kāi)發(fā)的工程師都能理解。因此，基于模型的測(cè)試應(yīng)該對(duì)所有專家具有可讀性和可理解性，而不僅僅只由少數(shù)測(cè)試專家才能理解。