Medical Manipulator Shape Estimation via Movable Sensor

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current medical manipulator systems face challenges in accurately estimating the bent shape of flexible portions within body cavies and controlling the manipulator effectively, leading to potential errors and instability during procedures.

Innovation Solution

A medical manipulator system equipped with shape sensors that move forward and backward along the manipulator channel, calculating longitudinal-direction positional information, and estimating the bent shape of the manipulator based on detected shape information, allowing for real-time control parameter calculation and manipulation control.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If shape sensors are moved forward and backward along the manipulator channel to detect shape information, then measurement precision of manipulator bent shape is improved, but device complexity increases due to additional driving mechanisms

Engineering Contradiction:

Improvebent shape detection precisionVSAvoidshape sensor driving mechanism complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The shape sensor driving portion is designed to serve dual functions: it drives the shape sensor forward and backward along the manipulator channel for shape detection, and simultaneously drives the manipulator itself. This multi-functionality reduces overall system complexity while maintaining high measurement precision through continuous shape monitoring.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent combines the shape sensor driving function with the manipulator driving function into a single integrated driving mechanism. By merging these functions, the system avoids the need for separate driving mechanisms, thereby reducing device complexity while enabling precise bent shape detection through the movable shape sensor.

Inventive Principle:

Principle #5Merging (Combining)

2Reliability

If shape information is continuously updated by comparing detected shapes with previous cycles, then reliability of manipulator control is improved, but loss of time increases due to continuous comparison and updating operations

Engineering Contradiction:

Improvemanipulator control reliabilityVSAvoidtime for shape information updating

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The shape information updating operation is performed selectively rather than continuously. The system compares detected shape information with previous cycle data and updates only when necessary, reducing the time overhead while maintaining control reliability through periodic verification.

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The shape detection and comparison operation continues throughout the manipulator's operation, allowing real-time monitoring and updating of shape information. This continuous action ensures reliability without requiring separate update cycles, as the system constantly tracks manipulator shape changes.

Inventive Principle:

Principle #20Continuity of useful action

3Stability of the object's composition

If high-frequency cut-off filters are applied to control parameters for correction, then stability of manipulator operation is improved, but loss of information increases due to filtering out high-frequency components

Engineering Contradiction:

Improvemanipulator operation stabilityVSAvoidhigh-frequency control information

Core Design Contradiction:

Stability of the object's compositionVSLoss of information

Solution Approach 1:

The control system dynamically adjusts the filtering applied to control parameters based on the operational context. By making the filtering degree adjustable rather than fixed, the system can maintain stability when needed while preserving high-frequency information when it contains useful control data, thus reducing information loss.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The cut-off frequency parameter of the filter is made variable rather than fixed. The system can change the filter parameters adaptively to balance stability and information preservation, allowing high-frequency components to be retained when they contain important control information while still filtering out noise when stability is the priority.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS11478306B2Shape acquiring method and controlling method for medical manipulator

Publication Date: 2022.10.25 OLYMPUS CORPORATION(JP)

AI summary

A medical manipulator system according to the present invention is provided with: a manipulator; a manipulator channel; a route that extends along the manipulator channel; a shape sensor that detects shape information of the manipulator channel; a shape-sensor driving portion that causes the shape sensor to be driven; a manipulator driving portion that causes the manipulator to be driven; a positional-information calculating portion that calculates positional information of the shape sensor on the basis of a driven amount of the shape-sensor driving portion; a shape estimating portion that estimates a bent shape of the manipulator on the basis of the shape information of the manipulator channel and the positional information; a control-parameter calculating portion that calculates a control parameter of the manipulator from the bent-shape information; and a manipulator controller that controls the manipulator on the basis of the control parameter.