Guo Xiaojun

Feature points based image registration between endoscope image and the CT image

According to the special requirements of the minimally invasive surgical robot system, combined the CT images of the lesion site of the patient with the data implied in minimally invasive surgical robot, proposed a new fast feature point based local image registration method, can realize the registration for feature points on special tissue and general tissue. This algorithm introduces Euclidean distance between feature points as the measure of image registration; select the ICP algorithm framework to quickly solve the registration transformation function. Through testing of medical images, experimental results show that the algorithm can match the overall structure of the image information but also align the interested physiological anatomy position of image. Registration results are very satisfactory. This method is a fast, accurate and robust medical image registration method.

Study of input-output stability rule of elastic motion of flexible manipulator arm

The necessary and sufficient condition of input-output stability of control system and its significance to the desigan and control application of flexible manipulator arm are described in the place,then the necessary and sufficient condition of input-output stability is simplified to make the criterion simple and easy. It is pointed out in the end that the input-output stability criterion may be used to analyse the effect of end position addition mass and drive joint rotary inertia and mode rotary inertia on the input-output stability of control system of flexible manipulator arm.

Notice of Retraction Route chart of the effect of the end position addition mass on the parameter change of flexible manipulator arm

The dynamic model of flexible manipulator arm having addition mass block on its end position is deduced in the first place, then several parameters of flexible manipulator arm impacted by its end position addition mass are enumerated, the effect of the end position addition mass on the parameters is exploded through route chart, it is favorable to subsequent analysis and computation that program calculation illustrates that the effect of the end position addition mass on the parameters is not more complex than the description by the formulas.

The study of robot actuator control based on fuzzy algorithm

The actuator control system of teleoperation surgical robot requires high precision, fast response, strong anti-interference and as much as possible no overshooting. Aimed at these characters, combined with new developments of modern control theory and introduced Fuzzy Adaptive control theory to make the PID parameters to fulfill real-time adaptive adjustment. The purpose is to improve the dynamic and the anti-interference and to restrain the system overshoot performance of the actuator control system. The mathematical model of the controlled system was established by theoretical analysis. The simulation and the comparison with the conventional PID control proved the feasibility and effectiveness of the proposed algorithm.