Surgical Robot Wrist Joint Segmentation for Motion Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Surgical robot arms face challenges in achieving a wide range of motion and kinematic functionality, particularly at the wrist joint, where certain attitudes are difficult to reach and control, limiting the versatility and precision of surgical procedures.
Innovation Solution
The design incorporates a spherical joint with a Hooke's or universal joint and a pantograph mechanism, allowing for three degrees of rotational freedom and preventing translational freedom, coupled with a control rod that translates laterally to alter the attachment's direction, enabling significant angular deflection and compactness, facilitating close proximity to patients and multiple arm operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a typical robot arm with rigid links and articulations is used for surgical procedures, then the arm can approach the patient in different ways to perform a range of surgical procedures, but certain attitudes in the core of the wrist joint's range of motion are difficult to reach or have poor control
Solution Approach 1:
The wrist joint is divided into multiple independent articulations (first articulation with first range of motion, second articulation with second range of motion). Each articulation is controlled independently by separate actuators, allowing the motion space to be segmented and controlled in a way that avoids singularities and improves controllability across the entire range of motion.
Solution Approach 2:
The patent employs dynamic control of multiple articulations where the actuators can independently adjust the position and orientation of each link. This dynamic coordination allows the system to navigate around difficult-to-reach attitudes and maintain optimal control throughout the range of motion, transforming static joint limitations into dynamically solvable configurations.
2Adaptability or versatility
If the wrist joint is made highly mobile to allow multiple orientations of the end effector, then the arm can perform a wide range of surgical procedures, but the structure becomes more complex and difficult to control
Solution Approach 1:
The complex wrist joint is segmented into multiple simpler articulations, each with a specific range of motion and controlled by a dedicated actuator. This segmentation reduces the complexity of controlling a highly mobile joint by breaking it down into manageable, independently controllable components.
Solution Approach 2:
The multi-articulation wrist joint design provides universal functionality, allowing the end effector to achieve multiple orientations and positions through coordinated motion of several articulations. This multi-functional design consolidates what would otherwise require separate mechanisms into a single integrated wrist assembly.
3Productivity
If multiple robot arms are positioned close to the surgical site to perform procedures, then surgical versatility is improved, but weight-related control issues arise
Solution Approach 1:
The robot arm is divided into multiple modular links connected by articulations, allowing the system to be configured with appropriate link lengths and masses. This segmentation enables optimization of the weight distribution to reduce inertial effects and improve control, particularly when multiple arms operate in close proximity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration enhances the wrist joint's mobility and control, allowing for a wide range of surgical procedures with improved precision and compactness, enabling multiple robot arms to work in close proximity without weight-related control issues.
Implementation Method 1
The design incorporates a spherical joint with a Hooke's or universal joint
Implementation Method 2
The design incorporates a spherical joint with a Hooke's or universal joint
Implementation Method 3
The design incorporates a spherical joint with a Hooke's or universal joint
Implementation Method 4
The design incorporates a spherical joint with a Hooke's or universal joint and a pantograph mechanism, allowing for three degrees of rotational freedom
Data Source
AI summary
A robot comprising an arm extending between a base and an attachment for an end effector, the arm comprising: a first arm part; a second arm part distal of the first arm part; and a joint whereby the first and second arm parts are coupled together, the joint permitting the first and second arm parts to rotate relative to each other about at least two mutually offset axes; a control rod attached to the second part of the arm at a location spaced from the first and second axes, the control rod extending distally of that location along the first arm part; and a drive mechanism for driving the control rod to move relative to the first arm part and thereby alter the attitude of the second arm part relative to the first arm part.