Modeling And Redesign Of The Control Unit Of Colonoscope

As the technology of endoscope advances, colonoscopy has been widely used in clinical diagnosis and treatment of diseases of the colon. The emergence of the electronic colonoscope makes the operation of colonoscopy change from two-man method to one-man method. However, the traditional control unit of colonoscope is not able to meet doctors’ needs of single-hand operations in one-man colonoscopy. In order to solve this problem, this thesis proposes a new approach to redesign human-machine interactive products based on ergonomics and the axiomatic design theory, which is called time-domain method. With this new method, a redesigned control unit and a redesigned bending control mechanism of the bending section is presented. The redesigned control unit that has all the basic functions is capable of fulfilling one-hand operation needs, it is more efficient and easy to use. This thesis presents the whole redesign process with the following steps.First, based on ergonomics and anthropotomy, the principles of human hand motion and the manipulation force of fingers during grip is analyzed. Second, treated as an serpentine robot, the kinematic model of the bending section of colonoscope is built by the D-H approach. Through kinematic analysis of the bending section, the relationship between the input motion (rotation angles of knobs on the control unit) and the output motion(bending angles of the bending section) is achieved. Third, a new redesign method of human-machine interactive products is proposed, which is based on ergonomics and axiomatic design theory. With this new method, a redesigned control unit which has all the basic functions and the capacity of fulfilling one-hand operation needs is presented. Finally, based on Chinese anthropometry and hand posture during manipulation of the control unit, a16-DOF3D model of human hand is built. Based on the3D model and SolidWorks platform, the virtual interaction between hand and the new control unit is animated. Both the virtual and physical results verify the effectiveness of the new control unit.