Parallel Mobile Coil Mechanism for Large-Workspace Magnetic Navigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current magnetic manipulation systems for clinical applications face challenges in achieving three-dimensional motion with multiple coils due to large sizes and weights, leading to design complexity and limited control bandwidth, and struggle with real-time computation of composite magnetic fields.
Innovation Solution
A magnetic manipulation system utilizing a robotic parallel mechanism with at least three electromagnets and electromagnetic coils, actuated by a current control unit and equipped with a 3D position sensor, allows for dynamic magnetic field generation and control in a large workspace, using soft iron cores and low magnetic permittivity materials to maintain structural integrity and mobility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If stationary electromagnetic coils are used to generate magnetic fields for manipulation, then magnetic force and torque can be applied to medical devices, but the system complexity and fabrication difficulty increase when the workspace size is enlarged to match human body dimensions
Solution Approach 1:
The patent transforms stationary coils into mobile coils that can move dynamically within the workspace. The coil assembly is mounted on a robotic manipulator with multiple degrees of freedom, allowing the coils to be positioned dynamically to match the target location in the large workspace, thereby avoiding the need for a fixed complex stationary coil structure covering the entire workspace
Solution Approach 2:
The system divides the workspace into multiple regions that can be sequentially accessed by the mobile coil assembly. Instead of using one large complex stationary system, the patent segments the manipulation task into multiple positions, with the coil assembly moving to each position as needed, reducing the complexity at any given location
2Area of stationary object
If stationary electromagnetic coils are enlarged to cover a large workspace, then the workspace coverage is improved, but the control bandwidth is reduced due to increased inductance
Solution Approach 1:
By making the coils mobile rather than stationary and enlarged, the system maintains small coil dimensions (preserving high control bandwidth) while achieving large workspace coverage through dynamic repositioning. The robotic manipulator enables the small coils to access different locations, effectively covering a large workspace without the inductance penalty of large stationary coils
Solution Approach 2:
The patent adds the spatial dimension of movement to the coil assembly, transforming the problem from a two-dimensional planar manipulation (limited by coil size) to a three-dimensional solution where the coils can move to different positions and orientations, effectively expanding workspace coverage without increasing coil dimensions
3Force
If permanent magnets are used to create dynamic magnetic fields, then the magnetic field strength is improved, but the control bandwidth is reduced due to large inertia and limited motion range
Solution Approach 1:
The patent replaces permanent magnets with electromagnetic coils that are moved by a robotic manipulator. This substitution allows for stronger magnetic fields (through controlled current) while maintaining high control bandwidth, as the electromagnetic system can be controlled more rapidly than mechanical permanent magnet systems with large inertia
4Speed
If mobile electromagnetic coils are used instead of stationary coils, then the control bandwidth is improved and safety is enhanced by ability to switch off field, but the design complexity of positioning mechanism increases
Solution Approach 1:
The robotic manipulator serving as the positioning mechanism is a universal system that can position the coil assembly in three-dimensional space with multiple degrees of freedom. This multi-functional manipulator handles both positioning and orientation tasks, reducing the need for separate specialized positioning mechanisms for each degree of freedom
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
Enables precise navigation and control of magnetic devices in a large 3D workspace with improved control bandwidth and safety, as the system can generate desired magnetic fields and switch them off, overcoming the limitations of stationary coil and permanent magnet systems.
Implementation Method 1
a current control unit and a robotic parallel mechanism are configured to generate desired dynamic magnetic fields in desired positions within a workspace to control a magnetic device
Implementation Method 2
the electromagnetic coils having soft iron cores, wherein the currents supplied by the control unit is configured to generate dynamic magnetic field in the soft iron core's linear region
Data Source
AI summary
A magnetic manipulation system and method for moving and navigating a magnetic device in a body are provided. The system includes a robotic parallel mechanism having at least three electromagnets and at least three electromagnetic coils coupled to the at least three electromagnets, respectively. The electromagnetic coils are actuated to keep the electromagnets in static conditions or move the electromagnets along a desired trajectory, a current control unit supplying currents to the electromagnetic coils which have soft iron cores. The currents supplied by the control unit are configured to generate dynamic magnetic field in the soft iron core's linear region. The current control unit and the robotic parallel mechanism are configured to generate desired dynamic magnetic fields in desired positions within a workspace to control a magnetic device, and a three-dimensional position sensor is configured for performing a close loop control of the robotic parallel mechanism.