Abstract: A multipoint data collection system uses multiple parallel data buses connecting a central controller to addressable sensor interfaces to permit any sensor to be connected to a central controller over any one of the data buses. Both ends of each data bus are connected to the central controller, allowing sensor interfaces to be addressed even if all data buses are cut. Faults on a data bus and defective sensor interfaces may be bypassed through one or more bypass buses that may be addressably switched into use as desired.

Abstract: A multipoint data collection system uses multiple parallel data buses connecting a central controller to addressable sensor interfaces to permit any sensor to be connected to a central controller over any one of the data buses. Faults on a data bus may be bypassed, or multiple sensors monitored simultaneously in real time, through the use of the parallel data buses. Digital address signals and analog data are transmitted on the same data bus, distinguished from one another by restricting the voltage range of the analog data to voltages above the voltage corresponding to a digital zero and below the voltage corresponding to a digital one.

Abstract: An apparatus for monitoring a vibrating structure, such as a bridge, uses multiple motion sensors spaced along the structure, each of which produces an analog raw data signal which is then filtered in anti-aliasing filters to remove substantially all frequency components of the signal above a selected cutoff frequency, f.sub.co. The filter outputs are connected to addressed inputs of an analog multiplexer which then multiplexes the signals in response to a channel address clock which repeatedly generates a sequence of channel addresses to scan the data input channels at the multiplexer corresponding to the addresses in the sequence. The complete sequence of addresses is repeated at a frequency of at least twice the cutoff frequency to obtain substantially simultaneous samples from the sensors so that data from different sensors may be correlated. The multiplexed signal is then converted to digital form and stored.

Abstract: A mechanical-to-electrical transducer arrangement wherein a combination of signal preamplifier and programmable analog signal processing circuitry is disposed immediately adjacent the transducer's sensor cell where low losses a low noise coupling into the signal path can be achieved. The programmable analog processing includes differentiation, filtering, integration, amplification and elective disconnection of the sensor cell to enable rapid transient signal recovery. Provisions for generation of transducer identification code and test signals in the processing circuitry and communications by way of a two wire time shared communication path is included.