The Development Of Servomechanism Based On The Embedded Real-time Operating System

The servomechanism is one of the automatic control systems,and it is applied into lots of fields. With the development of the computer and power electronic technology,the servomechanism develops very quickly. The real-time operating system is added into the control system along with the control system's function developing. The control system's response must be finished in dead-line time. The control system matches up every section according to certain order, and usually runs by paralleling multitask. In this paper, the real-time operating system is added into the control system to control the chair on the boat. The system controls the chair adjusting continually with the boat, in order to add comfort to the passenger in the chair. The study of this paper can improves the people's quality of life and has some value. The hardware of the system is designed based on recommending the sections and the theory of the servomechanism. The system selects DC servo as the execute component by comparing with AC servo. Transistor amplifier and DC servo are used as speed ring. the computer is acted as the adjuster of position, and the transfer function is designed. The PID control algorithm is selected in this system based on analyses several algorithms. The system selects selsyn as the monitor of position feedback. The system controls the output of DC according to the error value that the feedback signal from the selsyn is compared with the input. Because the embedded real-time operating system is one new operating system, in this paper its characters, actuality and evaluating indicator are sum up in brief. Several real-time operating systems are used at present is introduced in this paper. The cost is taken into account and the system usesμC/OS-Ⅱ. The kernel of μC/OS-Ⅱ is analysed .The task management , the time management , ISR, inter task communication (signal, message and massage mail box)are introduced. According to the real-time and multitask of the real-time operating system, the system is divided into several sections. The tasks are created and PRI is defined. In this paper, limited position of software is realized because the chair's range is limited.The PID control algorithm is translated into program.。After design of the whole system,it is simulated and tested on the stand. The signal from the machine of sine is replaced for the signal of collection, and the system is run and debugged to test the hardware and software. Every question is answered in the fact, and the system works well, and requirements on performance indices are met satisfactorily. In the end of this paper, questions to worked out in the future are proposed. The character of this paper is that the embedded real-time operating system is applied in the traditional design of servomechanism. The multitask is attempered and controlled in real time. In other words, the two systems are attempered and controlled in real time according to PRI. It has value about the embedded real-time operating system.