Kinemetrics, Inc

Kinemetrics' VDAS Field Sensor Station (VFSS) provides a complete Sensor Subsystem that provides a turnkey capability to calibrate and record data from a user specified sensor. Seismic, infrasound, or hydroacoustic data are then transmitted to the VDAS Data Acquisition Center (VDAC). The VFSS is a robust solution intended for 24 hours a day, 7 days a week operation in remote locations where the cost of maintenance demands a high reliability solution.

The VFSS consists of the Q730B digitizer, Global Positioning System (GPS), Wellhead Terminal Unit (WHTU), Authenticator, communications, power, and ground. Kinemetrics' VFSS design relies on state-of-the-art COTS components manufactured in quantity by reputable vendors with a demonstrated ability to support their products.

The Kinemetrics/Quanterra Q730B digitizer is an advanced remote real-time data acquisition system that combines Quanterra's patented technology with industry-standard TCP/IP networking protocols. The Q730B analog front-end incorporates Quanterra's delta-sigma modulator (US Patent 4866442, others pending) and operates at an oversampling rate of 20kHz, with final output sample rates derived from digital signal processing in the DSP module. This A/D technology has outperformed all others in independent evaluation by Sandia National Laboratories.

Based on the commercially proven Q730, the Q730B has been miniaturized and repackaged by Kinemetrics into a rugged borehole package ideally suited to mission-critical application requirements. Not only does the Q730B offer the best dynamic range offered by any borehole digitizer, it also allows complete flexibility in data rate selection, including multiple sample rates and selectable digital filters with specified characteristics.

The Q730B features selectable gain and variable damping. Variable damping is implemented using a solid-state resistor network for precision and repeatability unmatched by motor-driven pots. The digitizer supports communications at speeds from 2400 baud to 38.4 kbps.

The Q730B uses an Aeroantenna to provide the digitizer with the precision timing necessary for precision event location. The GPS processor is contained within the Q730B digitizer, protecting it from environmental extremes for longevity.

Kinemetrics' WHTU provides easy interconnection of the downhole analog, digital, and power cables with the power, ground, and communications elements. The WHTU mounts on the borehole casing with a collar and universal flange that allows the same WHTU design to be used with all casing sizes. The WHTU incorporates a universal mast mount to facilitate sensor removal/installation with the WHTU in place. All WHTU components are made of stainless steel to further minimize maintenance.

The internal connections of the WHTU are watertight even when the WHTU is open to minimize water damage during maintenance actions. Most maintenance actions can be accomplished from the external Maintenance Enclosure that includes test points and a console port for the Q730B and provides secure connections to power, ground, GPS and communications components. Both the WHTU and Maintenance Enclosures are lockable and have intrusion-detection. The WHTU is insulated to protect WHTU electronics from environmental extremes and to reduce temperature variations within the borehole that could adversely impact Long Period (LP) performance.

Kinemetrics has implemented a Vault Enclosure for those installations requiring a below-ground installation. The Vault Enclosure uses the same design principles and components used in the WHTU.

The VFSS includes all internal digital cabling and connections to the GPS antenna. The user is responsible for power cabling and analog cabling from the sensor to the WHTU.

The VFSS was designed to allow easy upgrades to meet the future requirements of the nuclear treaty verification community. The Kinemetrics borehole authenticator is a stand-alone hardware device that is plug compatible with the digitizer and the WHTU. The borehole authenticator is configurable to sign data and verifies commands received from the VDAC. All data and signatures are transmitted from the borehole in Alpha (CD-1) to eliminate verification failures resulting from reconstruction at the Data Center. Commands and signatures are presently implemented in proprietary formats but will be available in CD-2 as that format is defined.

Kinemetrics' VDAS provides communications between sensors and the VDAS Data Acquisition Center (VDAC) using an Intranet concept implemented using only COTS products. Kinemetrics has designed the VDAS as a virtual private network with connectivity achieved using COTS routers. This strategy allows the user to quickly configure adaptive networks that are independent of proprietary data formats and communications schemes.

Data is transmitted using Transmission Control Protocol/Internet Protocol (TCP/IP) Serial Line Internet Protocol (SLIP) protocol. SLIP is an industry standard method of encapsulating IP packets so they can be sent over a modem. The physical communications links can be any combination of dedicated copper; leased line; fiber optic; VHF, UHF or Spread Spectrum radio; or satellite. The COTS routers support half- and full-duplex, multipoint, and multidrop communications on these mediums. Host nation radios can be used in the VDAS since the router is configureable to match the characteristics of the radio.

The use of COTS offers a high degree of reliability and flexibility while supporting varied communication topologies required to meet local topographical, infrastructure and regulatory standards. The application of Internet standard COTS products to nuclear treaty verification leverages on the development resources of a market with millions of users.

Communication repeater designs are available to support extended network topologies and physical connections.

Power and grounding is one of the least considered elements in a data acquisition system, and is often the one item where money is "saved" with inadequate design and equipment. As a system integrator with extensive experience in installations worldwide, Kinemetrics considers power and ground essential to the successful installation and continuous operation of a data acquisition system.

Kinemetrics was the first to use dual-stage transient protection on all inputs to our recorders and is one of the few seismic equipment vendors to have CE certification for our recorders and sensors. We have worked with specialists from other companies to design optimal protection by building protection circuitry into our equipment. Kinemetrics' cable design ensures that our systems are protected from transient damage from lightning or electrostatic discharge (ESD) and to minimize both EMI/RFI emissions and susceptibility. All external connections are protected with double stage transient protectors and grounding straps are provided. Air terminals are provided to minimize lightning damage.

The VFSS can run from AC Power (80-132 and 180-264Vac, 43-63Hz) or from DC power (10-36Vdc). Power designs are available for AC, solar, thermoelectric, and wind-power to meet the station specific needs.

The user provides the appropriate local ground connection and is responsible for protecting external power cabling, and user provided data connections.