Research Of Multi-DOF Force Feedback Technology

With the development of sensor and computer technology, the research of haptic interaction is getting more and more attention. As an important part of haptic interaction, force feedback technology is widely used in various fields, such as virtual reality, UAV and teleoperation robots. Abroad research of force feedback technology started very early and many mature commercial force feedback equipments and extensible software platforms are developed. However, compared to abroad research, domestic research is still in early stage, not only reflected in design of hardware and mechanical, but also in software system design which is lack of generic, expansibility and modularization.In order to solve these problems, this thesis designs a new multi-DOF force feedback system including structure, hardware and software design. The end of the new force feedback equipment has multi degrees of freedom, including 3 translations,3 rotations and 3 grasping. Hardware design focuses on data acquisition of photoelectric encoder and motor control. In addition, it also realizes the serial communication with computer. Software design consists of detection and control software and virtual reality software. Detection and control software achieves the interaction between force feedback equipment and computer. Virtual reality software is utilized to build the virtual environment. The multi-DOF force feedback system has the feature of simple decoupling, large workspace, high accuracy, generic and extensible software.Key work and innovations of the thesis are divided into four points. (1) The structure design realizes automatical decoupling the freedom of translation and rotation by mechanism which can avoid complex software decoupling. (2) In hardware design, differential circuit is used to enhance the interference immunity of photoelectric encoder signals. As the MCU’s coprocessor, CPLD is introduced to improve the speed of data processing in hardware system. (3) In software design, modularization is utilized to build the detection and control software which has an interface of data communication with virtual reality software. So that the software can be compatible with multi virtual reality software including CHAI-3D. (4) Position measurement and calibration experiments can illustrate the high accuracy of this force feedback system.