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ABSTRACT
In surgery, surgical instruments are essential tools. In recent years, non-invasive
and minimally invasive surgeries are replacing many standard surgical approaches. In
cardiac surgery, dedicated non-invasive surgical instruments are needed. Meticulous and
reliable are needed in non-invasive clamps and tweezers. Theirs performance
requirements are block the vascular, but cannot damage the vessels’ walls in surgery. In
addition to the influence of ratchet of the head of hemostat, the best values of clamping
force must be chosen for achieving to block the blood and not damage the vessels’ walls.
Otherwise it will appear in the surgical to bleed, even to result in death duo to bleeding.
Currently foreign each hemostat is marked with clamping force values, which
allows doctors to decide what a reasonable choice for clamping blood vessels to stop
bleeding in order to ensure safe operation, reliable and effective. But in domestic
enterprises and hospitals, medical clamp jaw pressure measurements remain in the
artificial stage. Inspectors implement of the visual inspection and testing according to
structural and functional characteristics of the product.
Using modern new sensor technology, the subject provides reliable testing program
and studies how to more accurately measure the various types of medical hemostats’
clamp force. A measuring system of clamping force of hemostats has been developed in
the project. In hardware, FSR sensors (Force Sensing Resistor) of Interlink Electronics
company, 1121 voltage divider and PhidgetInterfaceKit 8/8/8 data acquisition
equipment of Phidgets company have been used. PhidgetInterfaceKit 8/8/8 data
acquisition equipment are been connected to PC (Personal Computer) by USB
(Universal Serial Bus). In software, some modules have been achieved, such as data
acquisition, system calibration, storage and retrieve of results of calibration, jaw
pressure measurement, label printing and report printing of measurement results. Then
two methods for calibrating have been discussed, and the one of the two has been
determined. Finally repeatability and reliability of the system have been verified. The
biggest repetitive difference of the same hemostat is 3.20g. At the same time, according
to some experiments it has been proved that JZ XAA040 hemostats are fit for veins for
bleeding Etc. The measurement system can provide a reference for manufacturers,
inspectors of surgical instrument and clinicians. The whole project will further enhance