中文摘要：

建立了基于超声影像导航的肝癌消融机器人系统误差传递模型．该系统主要由超声影像设备、导航软件子系统、定位装置和穿刺机器人四个模块组成．机器人系统首先通过三维超声重建、术前模型和术中实体的配准以及定位装置和机器人之间的坐标转换将肿瘤的目标靶点转化到机器人坐标系中，然后再控制机器人运动到指定的靶点位置进行治疗．首先分析上述流程，指出误差源．然后，利用齐次变换矩阵的微分矩阵建立靶点映射误差传递模型，并通过仿真实验验证了靶点误差模型的正确性．最后，对系统进行了精度测试实验，实验结果表明该系统的总体误差小于5mm，满足消融治疗肝癌的需求，能有效地提高肝癌的治疗效果．

英文摘要：

An error propagation model of the ultrasound image-guided robot for liver cancer coagulation therapy is established, which consists of an ultrasound imaging machine, a navigation software subsystem, a position tracking unit and a needle-driven robot. Through 3D ultrasound reconstruction, registration between pre-operative model and intra-operative physical body and coordinate-transformation from position tracking unit to robot, the robot system firstly converts the target of tumor into robot coordinate frame, and then it controls the robot to move to the designated position for therapy. The surgery procedure is analyzed firstly, and the error sources are pointed out. Secondly, error propagation model of target mapping is established by differential matrix of homogeneous transformation, and the model is validated by simulation results. At last, precision test for the system is taken, and the result shows that total error of the system is no more than 5 mm, which can meet the need of coagulation therapy for liver cancer and improve the efficacy of liver treatment effectively.