三自由度绳驱动RCM机构设计

摘要

RCM(Remote Center of Motion)机构是一种利用机构实现固定虚拟转动中心的机构。在微创外科手术中，由于切口的限制, 套管针需要绕着插入点进行转动或移动，RCM机构就可以为手术工具提供一个相对固定的插入点。这种机构结构简单、控制方便、成本低，可以提高外科手术的安全性。

基于以上的应用背景，本文开始介绍了三自由度绳驱动RCM机构的定义、优点和基本原理等，从自由度的定义和计算等初级理论开始，逐步深入分析了经典的两种RCM机构的构型及双平行四杆型远程运动中心机构的运动原理和等比同向传动型远程运动中心机构的运动原理，综合了绳驱动的原理和优点。着重阐述了三自由度绳驱动RCM机构样机的零件设计过程、装配过程。最终实现了用钢丝绳驱动RCM机构末端执行器绕虚拟远程运动中心二维转动，并可沿着自身轴线进行插入运动。机构具有结构简单，体积小，重量轻，控制方便和成本低廉等优点。

关键词：远程运动中心绳驱动机构设计手术机器

Title Three Degrees of Freedom Rope RCM Driven Mechanism Design

Abstract

RCM (Remote Center of Motion) is a kind of organization with which virtual fixed rotation center can be implemented. In minimally invasive surgery, because of the limitations of the incision, tracer has to rotate or move with the inserting point in due to the cut position. However, RCM can provide surgery tools a relatively fixed inserting point. The organization has brief architecture, convenience control, and low cost. RCM can increase the safety level of surgeries.

Based on the above background, this paper begins from the definition and advantages of the three degrees of freedom cable-driven RCM institutions, then I will introduce the basic principle of cable-driven RCM organization, analyzes the motion principles of the classic organization, which are bi-parallel pole tetrad remote-center-motion organization and the same direction moving remote-center-motion organization, and synthesizes the principle and strongpoint of cable-driven organization. This paper will be focuses on the three-degree-of-freedom cable-driven the RCM institutions prototype part design, assembly process. At this project, designing process, assemble process and testing process of 3 Degree-of-Freedom cable-driven RCM organization sample is expatiated. Through the driving moment estimation and steering gear selection, 2D rotation of the steel cable-driven RCM organization end round virtual remote motion center is finally implemented. And it has inserting motion along its own axes. The organization has many specialties, such as, simple architecture, small volume, and low weight.

Keywords: remote sports center cable-driven mechanical design surgical robot

目录

1.前言 (1)

1.1课题目的及背景 (1)

1.2国内外研究 (1)

1.3论文构成 (4)

2.绳驱动 RCM 的基本原理 (6)

2.1概述 (6)

2.2自由度的定义、计算及三自由度的优点 (6)

2.3 RCM 机构的定义及优点 (7)

2.4三自由度绳驱动RCM机构组成及基本原理 (7)

2.5本章小结 (8)

3.三自由度绳驱动RCM 机构分析 (10)

3.1概述 (10)

3.2两种典型的RCM 机构分析 (10)

3.2.1双平行四杆型RCM机构分析 (10)

3.2．2等比同向传动型RCM机构分析 (13)

3.3特殊的等比同向传动型RCM机构——绳驱动RCM机构分析 (15)

3.4本章小结 (17)

4.三自由度绳驱动RCM 机构组成的设计和选择及零件装配 (19)

4.1概述 (19)

4.2轴承外套的设计 (19)

4.3轴的设计 (20)

4.3.1轴的材料 (22)

4.3.2轴的结构设计 (23)

4.3.3轴的计算 (26)

4.4联轴器的设计 (35)

4.4.1.联轴器类型的选择 (36)

4.4.2联轴器扭矩的计算 (36)

4.4.3联轴器最大转速的校核 (37)

4.4.4联轴器轴孔直径的协调 (37)

4.4.5.联轴器相应部件安装精度的规定 (37)

4.4.6联轴器其他必要的校核 (38)

4.5机械臂的设计 (39)

4.6舵机的选择 (40)

4.7零件的装配 (44)

4.7.1装配的过程 (44)

4.7.2零件装配中存在的问题及解决办法 (49)

4.8本章小结 (51)