Research And Implementation Of Open Motion Controller Software System Based On μC/OS-Ⅲ

Currently, Internet of Things technology has been widely applied in security, logistics,manufacturing industry and so on, which uses RFID tags as its carrier and effectivelypromotes China’s industrial structure adjustment and informatization. As one of the coretechnologies of RFID packaging equipment, the motion controller has a significant impact onthe performance and production efficiency of the system. This paper analyzes the architectureof motion controller based on DSP and focuses on its open software system, includingembedded real-time operating system, motion control algorithms and interactive interface.The main contents of this paper are as follows:1. On the basis of requirements analysis, a system architecture consisting of PC andmotion controller card is designed. It applies a hardware solution which uses DSP as coreprocessor and FPGA as coprocessor, while the software system employs the embeddedreal-time operating system μC/OS-III and interactive interface based on Qt.2. Describing the architecture and features of μC/OS-III, its task status andpriority-based scheduling algorithm are analyzed thoroughly. Taking the strong real-timerequirements of the motion controller into account, the interrupt handling strategy based ondeferred post method is explored. The μC/OS-III transplantation to DSP and design of bootprocess is achieved later on.3. With analysis of the trapezoidal velocity planning algorithm, an improved algorithmin view of trigonometric functions is proposed against the jerk mutation problem of traditionalS-curve velocity planning, which is verified by simulation. Besides, in allusion to theinterference problems of control system in practical application, an improved incremental PIDalgorithm based on low-pass filter is proposed and its Simulink model is designed. Simulationresults show that the algorithm has better anti-interference performance.4. Based on introduction of features of cross-platform graphics library Qt, therequirements of interactive interface are concerned and two design principles are proposed:cross-platform and open. The design and implementation of major functional modules in theWindows OS is completed, and then the communication mechanism and data frame encapsulation is discussed.Finally, with the built of an experiment platform, the μC/OS-III run experiment,real-time test and the DC motor control experiment are carried out. The controller performs3026times task switching per second and its interrupt latency time is1.361μs. The resultsshow that the motion controller and its software system have good real-time performance andcontrol performance.