任务图模型中实时任务设计

Real-Time Tasks Design in Task Graph Model

仿真技术的进步推动了实时系统(如核反应堆、军事战场和fly-by-wire系统)的深入研究.用仿真方法解决实时问题,必须首先给出实时系统描述模型.TGM(task graph model)模型是实时系统描述模型之一,其模型最重要的成员是实时任务.使用量化仿真方法定义了实时任务的4种参数,并细分任务为子任务.此方法更易描述实时应用系统,更易构造TGM的执行模型,其层次化的结构更容易进行研究和软件实现.TGM模型及其任务设计已成功地应用于分布式三星实时侦察仿真系统.

The advancement of simulation technology promotes the deep research of real-time systems in urgent need such as nuclear reactor, military field and fly-by-wire systems. According to the simulation approaches, the description model of real-time systems must be presented. Task graph model is one of the description models. The real-time task in TGM model is very important. With the use of quantitative simulation method, the task is defined with four kinds of parameters and subtasks combining a task. By using this method, the real-time systems application can be described easily, the execution model of TGM can be constructed quickly, and its software can be researched and implemented quickly. TGM model and tasks design are successfully applied to the real-time simulation system of three surveillance satellites.