Manipulator Null-Space Coordination for Collision and Singularity Avoidance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current surgical robotic systems face challenges in managing multiple null-space objectives concurrently, leading to interference and cancellation of desired movements, which restricts the range of motion and dexterity of manipulator arms during minimally invasive procedures.
Innovation Solution
A robotic surgical system with a manager system that consolidates multiple null-space objectives using attributes like weighting, scaling, saturation levels, and priorities to achieve desired relationships and behaviors between objectives, allowing for coordinated joint movements that enhance manipulator movement and avoid collisions or singularities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple null-space objectives are managed concurrently without a manager system, then the system can attempt to achieve multiple movement goals, but the objectives interfere with and cancel each other, restricting the range of motion and dexterity of manipulator arms
Solution Approach 1:
The patent introduces a manager system as an intermediary component that receives multiple null-space objectives and consolidates them into a single coordinated command. This manager system processes weighting factors, saturation levels, and priorities to harmonize conflicting objectives, allowing the manipulator arm to achieve multiple movement goals simultaneously without interference or cancellation, thereby improving both range of motion and dexterity
2Reliability
If the system uses a manager system to consolidate multiple null-space objectives, then coordinated joint movements are achieved enhancing manipulator movement and avoiding collisions or singularities, but the system complexity increases
Solution Approach 1:
The manager system serves as an intermediary layer between the control system and the manipulator arm, consolidating multiple null-space objectives into coordinated joint movements. This approach improves reliability by preventing collisions and avoiding singularities through proper objective management, while the modular design of the manager system keeps the added complexity contained and manageable
3Adaptability or versatility
If redundant degrees of freedom are added to the manipulator arm to increase range of motion, then more null-space objectives can be achieved, but the mechanical complexity and cost increase
Solution Approach 1:
The patent changes the control parameters by introducing a manager system that processes weighting factors, saturation levels, and priorities for null-space objectives. This software-based approach enables the manipulator arm to achieve enhanced range of motion and multiple objectives without adding mechanical complexity, as the solution lies in the control algorithm rather than in additional mechanical degrees of freedom
Data Source
Figure 1A
Figure 1B
Figure 2~3
AI summary
Devices, systems, and methods for providing commanded movement of an end effector of a manipulator concurrent with a desired movement of one or more joints of the manipulator according to one or more consolidated null-space objectives. The null-space objectives may include a joint state combination, relative joint states, range of joint states, joint state profile, kinetic energy, clutching movements, collision avoidance movements, singularity avoidance movements, pose or pitch preference, desired manipulator configurations, commanded reconfiguration of the manipulator, and anisotropic emphasis of the joints. Methods include calculating multiple null-space movements according to different null-space objectives, determining an attribute for each and consolidating the null-space movements with a null-space manager using various approaches. The approaches may include applying weighting, scaling, saturation levels, priority, master velocity limiting, saturated limited integration and various combinations thereof.