Research Of VxWorks In Three-dimensional Optical Deformantion Measurement System

Due to the effect of wave stress, temperture and internal environment, the sailingship’s deformations will emerge. Because of the deformations, attitude angles betweenthe peripheral equipments and the reference center change. Before the peripheralequiments receive the parameters which are from the Center Attitude HeadingReference System, the parameters need be corrected. According to advantages of opticalcollimation and videometrics, the three-dimensional optical deformantion measurementsystem can acquire images and obtain the three-dimensional deformation angles. Theprimary works of the computer used in the deformantion measurement system are asfollows: image acquisition, data handing, net-communication, system controling. It isone of the key elements to select a suitable computer and a suitable operating system inorder to achieve highly efficient measurement. According to the applications ofdeformantion measurement system, module of deformantion measurement is desigened.At the same time, VxWorks(RTOS) is introduced, and the cross-developmentenvironment is built in order to research the VxWorks. The main contents of thisdissertation are as follows:1. The multi-tasks of deformantion measurement system are analysed and themodule of deformantion measurement is desigened. The form and theory of thethree-dimensional optical deformantion measurement system are analysed. According tocharacteristics of the interal date and tasks, after comparing some types of embeddedcomputer and operating system, the handware and software of the deformantionmeasurement module is desigened. PC/104is selected as the processing computer andVxWorks is selected as the operating system. Then VxWorks development environmentis built after configurateing BSP and loading the operating system.2. Based on the PC/104handware, the real-time characteristics of VxWorks ismeasured and analysed. According to multi-task characteristics of VxWorks, usingclock of handware, a method is designed to measure the real-time characteristics. Bythis method called timestamp method, the task switching time is measured and analysedin multi-task environment, semaphores task communication mechanism and additioncomponents condition. As well as, interrupt real-time of VxWorks is tested, and someguidances is put forward aim at developing tasks of the deformantion measurementsystem.3. To meet the requirement of three-dimensional deformations measurement,function of net-communication based on VxWorks is achieved. According to networkcharacteristics of VxWorks, the designs of the network communication is given basedon TCP and UDP. Meanwhile, the method is given in order to measure time delay andreliability of TCP and UDP network communication. And time delay influence of date bytes and frequency is measured and analysed. According to the result, thedeformantion measurement module depended on application can selected the suitablenet-communication mode.