The Design Of Wireless Pen Interactive System

With more and more multimedia has been used for business and teaching applications, the conventional mice and other low-end remote products applied as the key communication devices for display, are lack of writing convenience, smoothness and limit scope of usage, which make users cannot derive, calculate, record and append notes instantly.Aiming at solving actual problems which appeared in multimedia applications, the thesis designed a wireless pen interactive system which is more humanized. It can fulfill the mankind writing habit, strengthen the interaction between both users and audiences. The so called wireless pen--“Smart pen” is valuable for marketing spreading.Based on investigating wireless gesture track identification technology worldwide, the wireless pen interactive system designed by this thesis utilizes wireless chip CC2541, transports data through Bluetooth Low Energy protocol—BLE. It has less power consumption, better performance and strong adaptability. The system also utilizes a sensor chip MPU6050,which highly integrats both an accelerator and a gyroscope in one chip.To do so, it helps to decrease the difference between axes effectively,and reduce the area of PCB.The chip has a data processing unit which benefits for data fusion to calculate attitude information.Furthermore, with a upper computer display software, the system has enriched the functions and been used more easily.(1) Analyzing the current status of relevant products and studies and comparing with several common wireless gesture track identification technology, author has analyzed both advantages and disadvantages, chosen an inertia sensor positioning plan, and determined the research contents.(2) Comparing with main trend wireless communication protocols and combined with practical application requirements, author has chosen BLE as communication protocol, CC2541 as system core chip, MPU6050 as sensor chip, and quaternion method for attitude calculation as well.(3) Designed the schematics of RF communication, sensor, power management, interaction, clock and other modules of the transmitter, accomplished the PCB design and hardware welding, and debugged it at the same time.(4) Developed the system software in IAR EW for 8051,to make the transmitter accomplished functions like data collecting, processing and wirelee sending, and make the receiver accomplished functions like wireless receiving, HID communication and attitude calculation optimization;deigned the upper computer display system software in Visual C++, to provide a writing and drawing friendly environment.(5) Accomplished the combined test of functions of both hardware and software, tested the effect when used the system software and upper computer software together, and verified the usable of both the hardware and software.