Technologies


Polygraph Sensor Simulation and Testing System

Reference#: P01178


Polygraph testing invloves the measurement of four physiological responses: blood volume in the arim; respiration rate and volume in the thoracic and abdominal areas; and skin conductivity. Automated polygraph scoring algorithms have been developed to assist polygraph examiners to evaluation polygraph examinations. Each algorithm is designed for use with a specific signal interface usit because differences exist in the way that sensor signals are processed and sampled between different polygraph scoring systems. A method is needed to quantify the differences between different equipment.

JH/APL has developed a polygraph simulation system which will accept pre-recorded data from previous polygraph tests and convert the data into appropriate pressure variations representing changes in blood pressure and respiration, and conductivity variations in skin conductivity. The polygraph simulation system allows the same set of physiological sensor outputs to be consistently reproduced. The JH/APL technology replaces the polygraph sensros with a simulator which is capabile of recreating realistic, raw polygraph sensor data in a consistent, repeatable manner. In addition, this system can support the generation of simple test signal should the analysis warrant it. The simulation system is capable of recreating the same raw sensor data inputs to each singal interface unit consistently. Also, since digitized polygraph data are available, a comparison of that data and processed data from each of the units is possible. This technology provides flexibility and allows for thorough analysis of the differences between signal interface units and an understanding of how the raw sensor inputs are processed. The invention may also allow the units to be calibrated and will also have uses in the training of polygraph examiners.

CONTACT:
Mr. J. E. Dietz
Phone: (443) 778-2782
ott-techmanager5@jhuapl.edu