Abstract
Waist circumference as an estimate value of the visceral fat is measured for the diagnostic criteria of the metabolic syndrome. At the medical examination, waist circumference is usually measured with tape measure manually. Thus, obtained values should include non-neglective error. Additionally, the values of waist circumference will be personal information not to be known to others and it is also discomfort for women that someone touches their abdomen area. From this point, we have developed the new system for the non-contact measurement of abdominal cross section and waist circumference using a laser displacement meter. In this system, the laser displacement meter was attached at the waist level on the fulcrum which turned around the body segment. By the measured distance between the body surface and the laser sensor, the length from the center of the platform to the body surface was calculated by every small angle of 0.72degree so as to calculate the waist circumference and an abdominal cross-section. The designed system consists of pulse motor driving controller, distance measurement amplifier and the personal computer system for the operation of measurement and the graphical indication of data. The subjects were stood at a standstill position at least three seconds on the platform during the measurement. For the evaluation of the accuracy of the system, the five known circumferences with seven different cross-sections were measured. The linear correlation between the measurement value and the known data (y=1.0002x, R2=0.9998) was obtained within the 0.6% error range. The measured waist circumferences (60 to 100 cm) by 34 subjects were compared to manually obtained values. The differences were about 2-3 cm (within 3.5% error range of circumference).
