在商用车辆自动变速器功能/软件开发中的试验策略

Test Strategy in the Function/Software Development of Automatic Commercial Vehicle Transmissions

商用车辆的自动变速器为企业和驾驶员带来许多好处。企业可从降低燃油消耗、增加有效负载及减少维修费用等方面获益[1]。而驾驶员则提高了舒适性和安全性。这就是为什么自动变速器在商用车领域市场份额不断扩大的缘故。随着建立在软件基础上的功能日趋复杂和客户及市场需求的不断增加,在误差成本、质保和公平交易方面的危险也随之增加。为提高竞争力和满足客户在质量和成本方面不断增加的要求,有必要建立一个有效的试验策略。功能和软件试验的挑战在于应用合适的试验策略在增加复杂程度的同时确保质量,而不明显增加成本并满足越来越短的“时间就是市场”的需要。有效开发基于软件的电子系统的先决条件是定义试验方法,使得试验可在关键的研发阶段进行。本文的第一部分叙述了ZF在经典功能/软件开发中常用试验方法。第二部分探讨了现代化开发手段下的更多细节和附加的试验方法。两种试验方法相互比较,采用有用的误差在环评价它们的效率。准备投入生产的产品则同时采用上述两种方法进行开发。

Automatic transmissions for commercial vehicles offer advantages for both the fleet owner and the driver. The fleet owner benefits from lower consumption, increased payload and reduced maintenance costs . For the driver, advantages emerge in the area of comfort and safety. That＇s why the market share in automatic transmissions is continually rising in the commercial vehicle sector. The growing complexity of software-based functions and the increasing market and customer require- ments, however, are resulting in greater risks with regard to error costs, warranties and fair dealing. To improve competitiveness and to meet the customers＇ consistently increasing quality and cost requirements in the area of software-based functions, an efficient test strategy is necessary. The challenge for function and software testing is to ensure quality in the case of increasing complexity by applying a suitable test strategy, without considerably increasing costs in the process, as well as reacting to shorter and shorter ＂time to market＂ requirements. The prerequisite for efficiently developing software-based electronic systems is a defined test method in which tests are performed during decisive development phases. The first section of this article describes a test method as it is used at ZF in classical function/software development. The second section explores in more detail an additional test method taking into consideration modern development methods. The two test methods are compared and their efficiency assessed using the available error loops. Products ready for production are developed using both of these methods.