Abstract: A method for weighing vehicles moving on a bridge deck pavement is provided. At least one vibration sensor is mounted on a lower side of the pavement to sense low frequency pavement vibrations generated by moving vehicle wheels and propagated in waves in the pavement. Vibration sensor output signals are provided to a computing device. Sensed vibration energy rate is computed and, with signals from vibration sensors mounted at two locations separated by a known longitudinal distance, vehicle speed is also computed. The weight of the vehicle is determined as the product of a calibration coefficient and the ratio of sensed vibration energy rate to velocity. Using vibration sensor signals indicative of wheel generated vibrations in the very near field and summing vibration energy rates computed from these signals during vehicle passage over the vibration sensors the weight of individual vehicles is computed when other moving vehicles are present.

Abstract: A method for weighing vehicles moving on a bridge deck pavement is provided. At least one vibration sensor is mounted on a lower side of the pavement to sense low frequency pavement vibrations generated by moving vehicle wheels and propagated in waves in the pavement. Vibration sensor output signals are provided to a computing device. Sensed vibration energy rate is computed and, with signals from vibration sensors mounted at two locations separated by a known longitudinal distance, vehicle speed is also computed. The weight of the vehicle is determined as the product of a calibration coefficient and the ratio of sensed vibration energy rate to velocity. Using vibration sensor signals indicative of wheel generated vibrations in the very near field and summing vibration energy rates computed from these signals during vehicle passage over the vibration sensors the weight of individual vehicles is computed when other moving vehicles are present.

Abstract: A seismic weigh-in-motion system (12) which utilizes a seismic sensor (32) mounted, off-pavement of the highway prior to the point at which the truck (10) enters the deceleration lane at the truck weighing station. The sensor (32) senses seismic vibrations which are transferred into the ground by the moving truck (10). Signals indicative of these vibrations are transmitted through a fiber optic cable (44) connected to a main processor (42) mounted in the weigh-in station. These vibration signals along with signals proportional to the speed of the truck (determined by speed detecting devices/processes (34, 36)) as the truck moves down the highway is processed in the processor (42) to provide an output which is indicative of the weight of the truck. Additional components such as soil temperature (28) and soil moisture content (30) measuring devices provide additional inputs to the processor (42) to increase accuracy of the system.

Abstract: A tornado warning system having means for monitoring seismic waves of a predetermined frequency range including long-period seismic waves and short-period seismic waves. The seismic waves are associated with and produced in the ground as a result of an approaching tornado. The warning system comprises means for detecting the seismic waves including the long-period seismic waves and the short-period seismic waves and for providing an electrical output indicative thereof. Circuit means are provided for processing the electrical output to provide an output signal indicative of the long-period seismic waves and the short-period seismic waves. Alarm means are provided for receiving the output signal from the circuit means to generate an alarm to warn of the presence of a tornado.

Abstract: A method and apparatus for detecting the seismic signal generated by a tornado and providing timely warning of the tornado's approach. The invention involves the use of a geophone or velocity transducer (3) to detect the seismic surface waves generated by the tornado. The output of the geophone passes to the microchip (4) installed with the alarm system (5) within the building (6). Within the microchip the signal passes through the A/D converter (7), to the band-pass filter (8), and then to the signal-to-noise comparator (9). When the signal-to-noise ratio exceeds a specified level, the switch (10) is closed and the alarm (5) is activated.