Design Of Camera Pan And Tilt Controller Based On Internet

In recent years, as more and more attention is focused on social safety, the development of video surveillances is rapid. The range of applications becomes wide and video surveillances go to various fields. In order to expand the scope of monitoring and improve the monitoring of vision, the pan and tilt can be used, which means to put a camera on a pan and tilt and to control the pan and tilt rotating. At the same time, the parameter of the camera lens can be controlled. On the other hand, the scope of monitor become large little by little, the need of remote monitor increase, and remote monitor based internet is very fit the requirement.In this paper, a camera pan and tilt system based internet is designed, include mainly two parts:servo control system and internet interface system. The servo control system consist a permanent magnet synchronous motor and a power supply inverter, which is controlled by dignital vector control scheme in DSP TMS3201f2407. The vector control scheme can convert a three-phase synchronous motor in a static coordinate system as a DC motor, through PARK/CLARK coordinate transformation. So the position presise of servo system can be increased. The ENC28 J60 of Microchip is uesed in the internet interface as the core ciucut, it is an ethernet controller with 28 pin, SPI interface and is compatible with IEEE802.3 protocol. A gateway is designed by transplanting a simplified transport control protocol/internet protocol (TCP/IP) in embedded system TMS3201f2407, which can not only compelte the gateway, but also simplify the system, decrese the cost. An embedded web server established in the system, so the user can visite the pan and tilt just through IE explorer.At last, a control circuit of servo system has been designed based on DSP TMS3201f2407. Using this control system, the SVPWM and vector control algorithm was achieved. The position control loop was turned to reality. The experiments show that this scheme can satisfy the needs of camera pan and tilt. On the other hand, a WEB server was achieved base on the simplified TCP/IP protocol in TMS3201f2407 chip, which can be visited easily far away.