Surgical Robot End Control With a Virtual Remote Center
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for controlling surgical robots are limited to translation and rotation around a physical remote center of motion, requiring inconvenient preoperative and intraoperative adjustments, which hinders precise and safe surgical operations.
Innovation Solution
A method is provided to control the position and orientation of a surgical robot by establishing a virtual remote center of motion, allowing translation and rotation around this point, and using a master-slave control system to achieve precise surgical instrument movements through inverse kinematics calculations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional methods use a physical remote center of motion with dedicated parallelogram configuration, then the surgical robot can translate and rotate around the remote center of motion, but the preoperative and intraoperative adjustment of the position of the remote center of motion is inconvenient and requires additional translational mechanisms
Solution Approach 1:
The patent replaces the physical mechanical remote center of motion with a virtual remote center of motion defined by coordinate transformation algorithms. The control system uses mathematical models to calculate the position and orientation of the end effector relative to the virtual remote center, eliminating the need for physical adjustment mechanisms while maintaining the same surgical functionality.
Solution Approach 2:
The patent changes the parameter representation from fixed physical coordinates to dynamic virtual coordinates that can be adjusted through software parameters. The remote center of motion position is defined by controllable parameters in the coordinate system rather than fixed mechanical structures, allowing flexible adjustment without physical reconfiguration.
2Manufacturing precision
If conventional methods use fixed physical remote center of motion, then the control system is simpler, but the surgical precision and flexibility are limited due to inability to easily adjust the remote center position
Solution Approach 1:
The patent transforms the static physical remote center of motion into a dynamic virtual remote center that can be repositioned and reoriented during surgery. The virtual remote center coordinates are calculated in real-time based on surgical requirements, allowing the system to adapt to different surgical scenarios while maintaining precise control of the end effector.
Solution Approach 2:
The patent creates a universal control method that can handle multiple surgical configurations and remote center positions through a single coordinate transformation framework. The same control algorithm works for different instrument types, robot configurations, and surgical sites, eliminating the need for dedicated mechanisms for each scenario.
3Measurement precision
If the surgical robot uses master-slave control model with sensors at joints, then the motion information can be measured and mapped to slave hand, but the control accuracy of end position and orientation is insufficient for high-precision surgery
Solution Approach 1:
The patent implements a feedback mechanism where the actual position and orientation of the end effector are continuously measured and compared with the desired position and orientation calculated from the virtual remote center control. The control system uses this feedback to adjust the robot joint movements, ensuring high-precision control of the end effector position and orientation during surgery.
Data Source
AI summary
A control method for the location and the orientation of a surgical robot end, and a control method for a surgical robot. The control method for the location and the orientation of a surgical robot end comprises establishing a remote center point, and dragging a surgical robot, causing an end to move above the remote center point, the remote center point being a virtual fixed point about which an end of a surgical instrument rotates when turning past a target location; connecting a surgical instrument to an instrument base of the surgical robot; controlling the surgical instrument to pass the remote center point; obtaining an expected Cartesian speed of an end of the surgical instrument, calculating a target speed for each axis of the surgical robot, and controlling movement of each axis of the surgical robot according to the target speeds.