TECHNICAL NOTE: A LOW COST PRESSURE SENSOR FOR LONG-TERM UTERINE CONTRACTION MONITORING

Authors
M. YOUSEFI NAJAFABADI 1
B. bastani 2
H. ABRISHAMI MOGHADAM 2
S. GHARIBZADEH 3
Z. ASGARI 4
1 islamic azad university khomeini shahr
2 K.N.Tossi university of technology
3 Amirkabir university of technology
4 Tehran university of medical sience
Abstract
Home Uterine Activity Monitoring (HUAM) has demonstrated to be of great value for preventing preterm labor in recent years. In this research, a low cost monitoring device for non-invasive monitoring of the uterine activity in pregnant women is presented. The new device has been designed based on an inductive Colpitz oscillator and vertical displacement of a ferrite core in a coil. The resulting frequency of the oscillator is proportional to the pressure in the external surface of the abdomen. This frequency is measured by the portable monitor. A low-power static random access memory (SRAM) provides long-term data storage. The proposed sensor for detecting uterine contractions has light weight, high stability and low cost. This sensor is very simple to manufacture and use for long-term ambulatory monitoring of the uterine activity. Furthermore, this sensor can be calibrated using software. Other features of the sensor are, resolution of 0.13 mmHg, repeatability close to 96% and input range from 0 to 95.32 mmHg.

Keywords

The Modares Journal of Electrical Engineering
Volume 6, Issue 1
December 2006
Pages 85-93