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Power transmission for gastrointestinal microsystems using inductive coupling
Ma Guanying1, Yan Guozheng, He Xiu
1Institute of Precise Engineering & Intelligent Microsystems, Shanghai Jiaotong University, Shanghai, PR China. maguanying@sjtu.edu.cn
Physiological Measurement
|February 27, 2007
Summary
This study explores wireless power transmission for gastrointestinal microsystems using inductive coupling. Optimized systems achieved 170 mW power with 1.3% efficiency, meeting power needs for some diagnostic devices.
Area of Science:
- Biomedical Engineering
- Robotics
- Wireless Power Transfer
Background:
- Advancements in robotic capsules and microrobots for gastrointestinal disease diagnosis necessitate reliable powering solutions.
- Wireless power transmission is crucial for the practical implementation of these miniature medical devices.
- Inductive coupling offers a promising approach for powering ingestible microsystems.
Purpose of the Study:
- To investigate and optimize a wireless power transmission system for gastrointestinal microsystems.
- To analyze the impact of coil misalignment on power transfer efficiency.
- To evaluate different circuit topologies and coil configurations for improved power delivery.
Main Methods:
- A two-coil inductive coupling system was designed and analyzed.
- Coupling coefficients were measured under various axial, lateral, and pitch misalignments.
- Power transmission efficiency was optimized by adjusting tuning capacitors and transmission frequency.
- Serial resonant circuit (SRC) and parallel resonant circuit (PRC) topologies were compared.
- A multi-receiving coil structure was proposed to address orientation issues.
Main Results:
- The system demonstrated stable DC power reception up to 170 mW.
- A peak efficiency of 1.3% was achieved under optimal conditions.
- The serial resonant circuit (SRC) showed greater adaptability compared to the parallel resonant circuit (PRC).
- The multi-receiving coil structure helped mitigate orientation indetermination problems.
- Achieved power levels are sufficient for certain gastrointestinal microsystem applications.
Conclusions:
- Wireless inductive power transfer is feasible for gastrointestinal microsystems.
- Optimization of tuning capacitors and frequency significantly improves power transmission efficiency.
- SRC topology and multi-receiving coil designs enhance system performance and robustness.
- The developed system can provide adequate power for specific diagnostic microsystems.
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