Location Algorithm And Implementation Technology Based On Interactive Infrared Whiteboard

Interactive electronic whiteboard as an electronic product with strong interactivity is mainly integrated with broadband display technology and electronic whiteboard control technology,and supports users to write and control the computer through a touch mode.At present,interactive whiteboard is widely applied in such fields as multimedia teaching,videoconferencing and military exercise.Along with technological development,electronic whiteboard has continuously-increased size and is developed from the traditional single touch towards the multi-touch direction.In the field of large-size electronic whiteboard,infrared electronic whiteboard quickly occupies the large-size electronic whiteboard market by virtue of such advantages as low cost,long life,convenient installation,easy maintenance and more recognizable touch points.At present,the hardware technology of infrared whiteboard is quite mature and the main factor restricting the development of infrared whiteboard is software.Large-size infrared multi-touch technology is deeply researched in the paper.,especially on the location algorithm.The research results show that compared with the common infrared whiteboards in the market,there are disadvantages such as single scanning mode,accuracy of eliminating ghost points and coordinate solving algorithms,optimization of no response time on the premise of realizing the accuracy of the algorithm and serial communication.In order to solve such problems,the two innovations and following work are mainly concerned in the paper:(1)A location algorithm based on multi-angle scanning mode was also proposed in the paper;when the infrared electronic whiteboard system operates the four-point touch identification,the location algorithm can quickly and accurately eliminate the “ghost focus” and obtain the coordinates of the real touch point under the precondition of limited hardware resources,thus improving system accuracy and response rate on the basis of traditional location algorithm.(2)For multi angle scanning,there are fewer infrared rays.On the basis of new location algorithm,it is proposed in the paper to compensate the boundary dead zone and an improved method for scanning in key areas,reducing the error caused by the system,thus further improving algorithm accuracy and response rate.(3)STM32F103ZET6 chip based on ARM Cortex M3 architecture is taken as the control core of the infrared electronic whiteboard,and USB HID protocol is adopted for development to upload the coordinate information and the command information obtained thereby to PC through USB control unit,and then PC makes corresponding response operation after receiving the information,thus realizing the fast communication between the infrared electronic whiteboard and PC,namely plug and play,and the man-machine interaction function under the WIN7 system.