A novel single-ring absolute optical shaft encoder is designed by studying the encoding principle of traditional absolute optical shaft encoder in this paper. The description of the orientation algorithm of the encode...A novel single-ring absolute optical shaft encoder is designed by studying the encoding principle of traditional absolute optical shaft encoder in this paper. The description of the orientation algorithm of the encoder is specified, and an example for explaining the orientation arithmetic is given, which indicates that the theory of the encoder works. The visual interface to acquire signals of CCD is shown with VB,which provides reliable foundation to process data. The effective factors of measurement precision of the encoder are analyzed.展开更多
A constructive method was presented to design a global robust and adaptive output feedback controller for dynamic positioning of surface ships under environmental disturbances induced by waves, wind, and ocean current...A constructive method was presented to design a global robust and adaptive output feedback controller for dynamic positioning of surface ships under environmental disturbances induced by waves, wind, and ocean currents. The ship's parameters were not required to be known. An adaptive observer was first designed to estimate the ship's velocities and parameters. The ship position measurements were also passed through the adaptive observer to reduce high frequency measurement noise from entering the control system. Using these estimate signals, the control was then designed based on Lyapunov's direct method to force the ship's position and orientation to globally asymptotically converge to desired values. Simulation results illustrate the effectiveness of the proposed control system. In conclusion, the paper presented a new method to design an effective control system for dynamic positioning of surface ships.展开更多
This paper presents a vehicle navigation and monitoring system scheme based on GIS/GPS/GPRS. The whole system consists of vehicle terminal and monitoring center, the monitoring center and the monitoring terminal compr...This paper presents a vehicle navigation and monitoring system scheme based on GIS/GPS/GPRS. The whole system consists of vehicle terminal and monitoring center, the monitoring center and the monitoring terminal comprises a communication server, communication server is only responsible for data storage and forwarding, the monitoring functions are completed by the monitoring terminal. Therefore, after the map matching, control terminal is performed on the device display to achieve real-time monitoring of vehicle location. The monitoring terminal can also be parameters of the moving vehicle accurate location, velocity and state the necessary query and transmission scheduling control instruction to carry out scientific scheduling and management, and improve operation efficiency. If the vehicle encountered an unexpected condition, harm or left the restricted area, it also can send alarm information to the monitoring terminal, and then the terminal can receive assistance and support in time.展开更多
文摘A novel single-ring absolute optical shaft encoder is designed by studying the encoding principle of traditional absolute optical shaft encoder in this paper. The description of the orientation algorithm of the encoder is specified, and an example for explaining the orientation arithmetic is given, which indicates that the theory of the encoder works. The visual interface to acquire signals of CCD is shown with VB,which provides reliable foundation to process data. The effective factors of measurement precision of the encoder are analyzed.
文摘A constructive method was presented to design a global robust and adaptive output feedback controller for dynamic positioning of surface ships under environmental disturbances induced by waves, wind, and ocean currents. The ship's parameters were not required to be known. An adaptive observer was first designed to estimate the ship's velocities and parameters. The ship position measurements were also passed through the adaptive observer to reduce high frequency measurement noise from entering the control system. Using these estimate signals, the control was then designed based on Lyapunov's direct method to force the ship's position and orientation to globally asymptotically converge to desired values. Simulation results illustrate the effectiveness of the proposed control system. In conclusion, the paper presented a new method to design an effective control system for dynamic positioning of surface ships.
文摘This paper presents a vehicle navigation and monitoring system scheme based on GIS/GPS/GPRS. The whole system consists of vehicle terminal and monitoring center, the monitoring center and the monitoring terminal comprises a communication server, communication server is only responsible for data storage and forwarding, the monitoring functions are completed by the monitoring terminal. Therefore, after the map matching, control terminal is performed on the device display to achieve real-time monitoring of vehicle location. The monitoring terminal can also be parameters of the moving vehicle accurate location, velocity and state the necessary query and transmission scheduling control instruction to carry out scientific scheduling and management, and improve operation efficiency. If the vehicle encountered an unexpected condition, harm or left the restricted area, it also can send alarm information to the monitoring terminal, and then the terminal can receive assistance and support in time.