Laparoscopic Robot Tip Vibration Suppression via Feedforward Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Robotic medical systems face challenges in minimizing vibration at the instrument tip during laparoscopic surgery, as traditional approaches either require a 'soft' robotic arm with low natural frequency and high damping ratio or a 'stiff' arm with high natural frequency, both of which come with engineering difficulties and limitations.
Innovation Solution
A robotic medical system is configured with sensors and actuators to actively control instrument tip vibration by measuring real-time parameters and generating control signals to suppress unwanted vibrations, using a feedforward control model to predict and mitigate upcoming vibrations, thereby maintaining precise control without altering the robotic arm's natural frequency or damping ratio.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a soft robotic arm with low natural frequency and high damping ratio is used, then vibration at the instrument tip is reduced, but the robotic arm becomes less stiff and harder to control precisely
Solution Approach 1:
The system dynamically changes the control parameters of the robotic arm by adjusting impedance parameters in real-time. During vibration suppression, the system modifies the stiffness and damping parameters of the control model to counteract vibrations without physically altering the robotic arm's structural stiffness, thus resolving the contradiction between vibration reduction and positioning precision.
Solution Approach 2:
The system uses sensors to detect vibrations at the instrument tip and feeds this information back to the controller. The controller then adjusts the robotic arm's impedance parameters in real-time based on the detected vibration characteristics, creating a closed-loop feedback system that suppresses vibrations while maintaining the arm's inherent stiffness for precise positioning.
2Manufacturing precision
If a stiff robotic arm with high natural frequency is used, then positioning precision is improved, but vibration at the instrument tip increases
Solution Approach 1:
The system transitions from a static robotic arm design to a dynamic control approach where impedance parameters are continuously adjusted. The robotic arm maintains its stiff structure for positioning precision, but the control system dynamically modifies the effective stiffness and damping through impedance control to suppress vibrations at the instrument tip during surgical operations.
Solution Approach 2:
The control system changes the effective mechanical parameters of the robotic arm through software-based impedance control. By adjusting the damping and stiffness parameters in the control model, the system can suppress high-frequency vibrations generated by the stiff arm structure without compromising the positioning precision that the stiff structure provides.
3Object-affected harmful factors
If the robotic arm structure is modified to reduce vibration, then vibration control is improved, but the device complexity and redesign requirements increase
Solution Approach 1:
The system replaces mechanical modifications to the robotic arm structure with a software-based impedance control system. Instead of physically redesigning the arm to reduce vibrations, the system uses sensors and controllers to dynamically adjust control parameters, substituting mechanical redesign with intelligent control algorithms that suppress vibrations through real-time parameter adjustment.
Data Source
AI summary
Robotic medical systems can control vibration of an instrument tip. A robotic medical system can include a robotic arm, a sensor positioned on the robotic arm, and one or more processors. The robotic medical system can be configured to receive an input specifying a target position of the robotic arm. In accordance with the input, the robotic medical system can provide first actuation signals to cause movement of at least a portion of the robotic arm. During the movement, the robotic medical system can receive sensor signals from the sensor. The robotic medical system can generate processed signals based on the received sensor signals and generate control signals according to the processed signals. The robotic medical system can provide second actuation signals based on the first actuation signals and the control signals so that a vibration of the robotic arm is suppressed.