Formed by players previously core members of advanced sensor and solid state actuator group at Lockheed Martin's corporate lab, Active Signal Technologies Inc specializes in R&D of devices and systems based on piezoelectric, magnetostrictive, and electrostrictive materials for next-generation military and medical applications. The firm has developed a device to assess traumatic brain injury based on acoustic characterization of cerebral perfusion. For over a decade, the device - Brain Acoustic Monitor (BAM) - has been tested at R Adams Cowley Shock Trauma Center Device also tested for concussion detection at the Air Force Academy in parallel with neuro-psychological evaluation as well as being evaluated in the San Antonio Military Medical Center (SAMMC) for returning wounded warriors with head injuries. BAM testing for sports concussion assessment in college and high school athletes has also been initiated by the University of Virginia Brain Injury & Sports Concussion Institute. At its most fundamental principle of operation, device,is a brain stethoscope with a display. Although not audible by conventional or electronic stethoscopy, arterial pulse waves entering the brain produce predictable deformation of the skull that can be detected by sensors closely coupled to the skin of the forehead. Normal signals will appear as a normal arterial waveform while distorted waveforms are associated with some anomaly in brain physiology, generally temporary as with mild traumatic brain injury. Over the course of its development, this system has evolved from a laboratory signal analyzer to a hand held PDA system Several other devices have been developed using these "smart materials" and associated technologies as well; these devices run gamut from power dense drivers for control surface actuation in unmanned aircraft to a noise immune stethoscope to meet high fidelity cardiovascular sound auscultation requirements as well as noise-immune operation.
