Abstract: Apparatus and method is provided for performing detailed mine detection over variable terrain. An articulated robotic scanner comprises an articulated arm mounted to any vehicle such as a robot. One or more mine detectors mounted at the end of the arm. The arm operates autonomously to repetitively sweep the mine detector in ever forward advancing side-to-side arcs over the terrain. The vehicle can operate autonomously or be tele-operated. The position of the mine detector is monitored and known with respect to a known coordinate system. Sensors measure their position relative to the ground and relative to known co-ordinates of the mine detector. A controller determines the relative position of the ground and the mine detector and dynamically adjusts the mine detector's position to maintain a constant separation over variable terrain without ever contacting the ground or objects thereon.
Type:
Grant
Filed:
March 8, 1999
Date of Patent:
December 25, 2001
Assignee:
Minister of National Defence of Her Majesty's Canadian
Government
Inventors:
Yogadish Das, Kevin Russell, Nenad Kircanski, Andrew Goldenberg
Abstract: The present invention relates generally to the use of polyaryletherketone-based thermoplastic materials in high pressure, high temperature, production logging applications. A polyaryletherketone resin bonded with glass fibers is formed into a housing for formation evaluation sensors permanently located downhole. The housing is constructed by any of the following processes: filament winding, fiber placement, or compression molding or injection molding. When used in a production well, the housing encloses the formation evaluation sensors and protects the sensors from borehole fluids. Housing properties can be modified with changes in materials added to the resin in order for the housing to function as casing or coiled tubing. This would allow wireline or logging-while-drilling conveyed sensors passing through the casing or coiled tubing to sense the formation and borehole fluid properties.
Abstract: The present invention provides an apparatus and a method for determining the position of a first element relative to a second element. The apparatus includes a magnet being attached to the first element. First and second sensing devices are adapted to detect a magnetic flux density produced by the magnet and responsively generating first and second signals. The apparatus also includes a controller for receiving the first and second signals and responsively determining the position of the first element relative to the second. The present invention enables continuous calibration during the normal operation of the machine.
Abstract: An electro-optic voltage sensor comprises a voltage divider connected to an electric line and to ground and having two insulative compartments separated by an intermediate electrode connected to a Pockels cell. The intermediate electrode supplies to the Pockels cell a reduced voltage derived from the voltage supplied by the electric line to the voltage divider. Each insulative compartment comprises a homogeneous dielectric block with a thickness dependent on the division ratio of the voltage divider. The electro-optic voltage sensor has a very high safety level vis a vis the risk of strong short-circuits combined with mechanical and thermal stability guaranteeing great accuracy of operation and great reliability without special maintenance requirements.