Feedback Scheduling Research And Experimentation Design In Embedded Control System Of Linux

Embedded real-time control system is the integration of computer science and control engineering. It is the special control system in the support of processor. It has been the active research area. It is challenging for system analysis and system design, whether to computer scientist or to control engineer. So far, no the uniform method has been proposed for system analysis and system design. In this thesis, we explored some challenging aspects of embedded control system, such as analyzing and Linux based designing of embedded control system, co-design of control and scheduling, and feedback scheduling.The essence of embedded control system is computer-controlled system. But the difference between embedded control system and computer-controlled system is that embedded control system has no standard hardware interface and no standard software-designing criterion. The guidance and method of embedded control system design that has been concluded can guide our system design to a certain extent.Linux is the operating system that is resource-open, free, cut out freely. Linux embedded will decrease the products' cost greatly. Through researching the framework and running mechanism of Linux kernel, the well-suited control platform can be built and the better designing scheme can guide embedded Linux's development.In the past, control design and task scheduling were treated as two separate issues; in the result, CPU resource had been wasted. So the co-design of control and scheduling has been the very active research area, in order to design task control and scheduling algorithm and make task control and scheduling algorithm running, synchronistical and mutual, when embedded control system running. A double loop of feedback has been released that makes control and scheduling better for synchronous designing and running. From the perspective of control process, a control task can be divided into transient state and steady stale for running separately, which can utilize CPU resource more enough and improve the performance of control system. Still further, combine the divided tasks into optimal scheduling in the restriction of CPU resource, which should improve the performance ofcontrol system much more and can accept more control tasks. The emulating result has indicated that a co-design of control and scheduling algorithm can make system more flexibility, utilize the resource more enough, and gain better control performance.Scheduling model of Feedback that had been released by foreign scholar is fit for large control system, for example, airplane. For the purpose of applying the feedback scheduling in small-embedded products, the framework and model of dynamic proportional feedback scheduling has been released that is fit for small-embedded control system. The model of proportional feedback scheduling should decrease the pre-consumption of CPU resource, decrease the number of control algorithm version and increase the flexibility of control system. The emulation has also indicated that the better control performance has been gained, with the pre-consumption of resource decreased.In order to validate the algorithms' practical application through experimentation, we apply the algorithms in general motion control that has been schemed out multi-loop control system, such as the system of defending swing from the crane. This system has the properties of nonlinear model, real-time and bad environment, the main aim of which makes the cargo moving quickly and locating precisely. We have established the corresponding control platform, analyzed and designed software, hardware, and the algorithm. In the same time, in the basis of the planar control of the system, we have carved up the tasks for a co-design of control and scheduling and for feedback scheduling to exam the original idea.