Abstract: A laser control apparatus that controls a laser device acquires state data from the laser device indicating the state of the laser device every time a specific preset event occurs, such as the generation of a fixed number of discharge pulses, for example, and transmits this data to a monitor terminal. The monitor terminal transfers the received state data to a server device via a communication channel. In the server device, a database is updated and output data is generated based on the transferred state data. This output data is input to a display terminal via a communication channel, and is displayed on the display terminal.

Abstract: The pulsed laser control system comprises a plurality of controllers (2) through (6) for controlling devices (21) through (30) constituting the pulsed laser apparatus (1); parallel communication lines (P1) to (P4) for parallel connection of the plurality of controllers (2) through (6); an Ethernet (S) for serial connection of the plurality of controllers (2) through (6); parallel communication line (PP) for parallel connection between the external apparatus (10) and the main controller (2); and an Ethernet (SS) for serial connection between the external apparatus (10) and the main controller (2); wherein the parallel communication lines (P1) to (P4) and (PP) transmit signals for which realtime performance is required. With this construction, even if design changes are frequently made to a pulsed laser apparatus, the changes can be made easily and with little expansion space. Moreover, management of the devices constituting the pulsed laser apparatus can be easily performed.

Abstract: A laser device which repeats a cycle of burst mode operation in each of which continuous oscillating operations for continuously pulsatively oscillating laser light by a prescribed number of times and stopping operations for stopping the pulsative oscillation for a prescribed pausing time are alternately executed, controls the power supply voltage of the laser device so that each output energy of the pulsative oscillation can become coincide with a target value, finds the difference between the output voltage of each pulse and the target value at every pulse and, for a pulse for which the difference exceeds tolerance limits, corrects and updates the power supply voltage value stored in the voltage data table means corresponding to the pulse number of the pulse and the measured oscillation pausing time by using the control gain of a control gain setting means set in the block corresponding to the pulse number and the measured oscillation pausing time and the difference, so as to always make the pulse energy of

Abstract: The present invention discloses a system and a method for transmitting data in a shield machine and for calculating the filling amount of a void by detecting the distance to the natural ground. The system and the method are capable of transmitting analogue signals or signals of relatively high frequencies with reliability, enabling an unskilled operator to accurately detect buried articles and accurately carry out the back-filling work. Therefore, an optical rotary joint (100) is disposed between a rotary cutter head (10) and a non-rotary shield body (2) to count time taken to detect the peak value of a reflected signal larger than a standard value or time taken to detect the zero cross position present prior to the peak value. In accordance with the counted time, the distance between the antenna and the natural ground is calculated and displayed. Then, the void volume is calculated in accordance with the distance so that a target value of the back-filling amount is set.

Abstract: A position measuring apparatus easily and accurately detects the position of an underground excavator, such as a shield excavator, during the underground excavation, and particularly the position thereof on a horizontal plane. The position measuring apparatus comprises a transmitter (10) including at least two cable loops (10a, 10b) which generate AC magnetic fields; a receiver (30) which detects the AC magnetic fields and produces signals representative of the detected fields; and a computing unit (60) which identifies the signals with respect to the originating cable loop and which calculates the position of the underground excavator (20). The two cable loops (10a, 10b) are substantially perpendicular to each other. The receiver (30) includes two magnetic field detecting elements (S.sub.1, S.sub.2) which are substantially perpendicular to each other. The receiver (30) is rotatably driven so as to maintain the magnetic field detecting elements (S.sub.1, S.sub.

Abstract: A method and an apparatus for performing measurement by a resistivity method in order to detect the thickness of a sludge layer on the outer periphery of a shield machine. A Wenner electrode row (14) on the outer periphery of the machine is used to measure reference resistivities to thereby detect certain resistivities in the depth direction of the natural ground and the sludge layer thickness. At the same time, a dipole electrode row (16) is used to measure voltage distributions in the depth direction of the natural ground and in the direction of the arrangement of the electrodes. The ratios of the values measured by the measurement dipole electrodes to those measured by the reference Wenner electrodes are calculated, and their distribution is charted. When mutually equal values in the distribution map are connected together by continuous curves, a contour-pattern image is obtained, which enables a configuration of the collapse of natural ground to be determined.

Abstract: An apparatus for detecting a position of an underground excavator in tunneling the earth measures automatically: a three-dimensional position of the excavator relative to a predetermined reference position, or three-dimensional positions of a pair of underground excavators relative to each other. The excavators are disposed in opposite ends of a tunnel to be dug, and dig the tunnel toward each other.

Abstract: In the present invention, a first and a second projector means projecting rotating laser beams rotating at a predetermined period are disposed at two predetermined fixed points, respectively. A first, a second and a third photodetection means are disposed on a moving body to detect the photodetection timings with which laser beams are detected, and to detect photodetection height positions of the rotating laser beams. The rotating angles of the two rotating laser beams from the reference azimuth are calculated on the basis of the outputs from the first, second and third photodetection means, and the positions and heights of the respective photodetection means are calculated from these data. Thus are the position and attitude angle of the moving body are measured with high accuracy, and these data are displayed on a real-time basis.