Research In Electromagnetic Positioning System For Laparoscope

Abdomen is the important parts of the body that is composed by many organswhich is responsible for digestion. The pelvic diaphragm between entrance and cavity isdivided into abdominal cavity in clinical medicine. The internal organizational structureof abdomen is complex, include a variety of important organ and mainly part of the totaldigestion. Above all, research in Laparoscope operation method is worthy of attention.Laparoscope develops rapidly in recent years in our country. When the camera isput inside human body, the position and orientation cannot be change frequently.Further more the instruments inside human body may interference with each other andcourse losing line-of-sight. It is crucial to introduce a reliable and cost effective mannerto tracking the position and orientation in laparoscope.Based on the analysis of domestic and foreign related researching processing inthis technology, propose a kind of structure which is simple and convenient to trackingthe position and orientation inside human body. This paper mainly consists of followingwork.1. There are many kinds of structure in electromagnetic positioning technology.Select and design a kind of electromagnetic position system extremely suitable forusing in laparoscope.2. Provide efficient mathematical derivation to verify using single3-axis magnetoresistor can determine both position and orientation of the sensor in6degrees offreedom.3. Design the controlling part using MCU STC90C516, which is mainly used forcollecting measuring data of the magnetic resource. Finished the design work ofmagnetic measuring circuit using PROTEL DXP. Using earth’s magnetic field toverify the entire magnetic measuring system.4. Simulating the physics reaction using DC power to excitation magnetic coil.Comparison and analysis of the results using MATLAB to decide the physics sizeof the magnetic coil.5. Construct the magnetic source circuit with DDS synthesizer AD9850,microcontroller chip STC90C516and power amplifier module. AD9850canprovide both AC excitation and DC excitation，different port can support different tracking module.