JPH0695019B2 - Line-of-sight angle detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION a. Field of Industrial Application The present invention relates to a line-of-sight angle detection device, that is, when an observer visually captures a target, the horizontal azimuth angle of the line of sight connecting the observer's eyes and the target. And a device for producing an elevation angle from a horizontal plane.

b. Prior Art FIG. 8 is a perspective view of a visual line angle detection device according to the prior art.

The telescope b having a function of projecting the crosshair a at infinity has a degree of freedom around the rotation axis and the elevation axis. The gantry c supporting the telescope b has a liquid level and a leveling mechanism for horizontally adjusting the line of sight at the time of initial adjustment. The angle scale is visually read using an optical reading device d for depression and elevation. Some devices detect this angle electrically.

The finger north gyro compass unit e is supplied with power from the cable f, detects the azimuth angle from the true north of the line of sight, and transmits it as an electric signal. This device is installed and fixed on the ground with a tripod g, and the cable f is used to supply not only the power supply for the gyro compass but also the power supply for illuminating the crosshairs of the telescope, and for outputting the azimuth angle of the line of sight.

c. Problems to be Solved by the Invention In such a conventional line-of-sight angle detection apparatus, a procedure such as installing a tripod after leveling the ground if necessary, assembling the apparatus, and horizontally adjusting the telescope axis is performed. It is also necessary to wait for the Shihoku Gyro Compass to settle. When moving to another point, you must wait until the Shihoku Gyro Compass stops. As described above, the conventional ones have the problems that it takes time to install, the preparation time is long, and the frequent movement is difficult.

Furthermore, since the observer operates while looking into the telescope, it is not possible to see the entire field of view, and it takes time to search for the target and prompt the telescope for it. Especially, there is a problem that it is difficult to track a moving target.

In order to solve such a problem, the present invention proposes a sight line angle detection device in which a portion of a site looking at a target, an azimuth angle of a sight line, and a depression / elevation angle detection means are incorporated in a helmet. And

d. Means for Solving the Problems The above-mentioned problems are associated with a helmet, a site attached to the helmet that forms an image at an infinite point on the line of sight, and a helmet for detecting the azimuth angle from the magnetic north of the line of sight. A fixed magnetic azimuth transmitter and a tilt angle detector fixed to the helmet to detect the angle of depression and elevation of the line of sight,
The visual line angle detection device is provided with an angle calculation means for calculating the azimuth angle and the elevation angle of the visual line based on the output of the magnetic azimuth transmitter and the output of the tilt angle detector.

e. Action The part of the site that looks at the target, the part of the sensor that detects the azimuth angle of the line of sight, and the angle of elevation from the horizontal plane are attached to the helmet to make it an integral structure, so simply overlay the target on the site image. The line of sight can be determined with. The direction of the line of sight is determined by the magnetic azimuth transmitter and tilt angle detector fixed to the helmet.

f. Embodiment FIG. 1 is a perspective view of a helmet portion of the line-of-sight angle detection device according to the present invention. Helmet 1 worn by the observer
A site 2 for projecting a crosshair to infinity, a magnetic azimuth transmitter 3 for detecting the azimuth angle from the magnetic north of the line of sight, and a tilt detector 4 for detecting the elevation angle from the horizontal plane are respectively attached.

FIG. 2 is a perspective view of a controller part of the visual line angle detection device according to the present invention. The controller 5 supplies necessary power to the helmet side through the cable 6, receives signals from the helmet side and performs signal processing, and displays the azimuth angle from the magnetic north of the line of sight and the elevation angle from the horizontal plane. And has a function of outputting these angles via the cable 8. The controller has a structure that can be operated by the observer by pulling it down from the neck.Power switch 5a, display changeover switch 5b, power ON-OFF and indicator lamp 5c for displaying a failure, and an angle signal for temporary holding. Switch 5d to display on the display, and switch 5f to select whether the transmission of the angle signal is automatic or manual with switch 5e
Etc. are installed. The power supply to the controller 5 is the cable 8
Supplied with.

FIG. 3 shows the optical system of the site section 2. 2a is a light source lamp,
2b is a focusing screen on which the pattern of the cross hairs 2e is printed, 2c is a collimator lens, and 2d is a half mirror. By placing the focusing screen 2b on the focus of the collimator lens 2c, the crosshair 2e is projected at infinity, and an error (parallax) due to the position of the eye E does not occur.

The magnetic azimuth oscillator 3 is a flux gate type magnetic azimuth oscillator. The coil part that detects the geomagnetism is supported by a gimbal structure like a pendulum, and has a structure that detects only the horizontal component of the geomagnetism regardless of the movement of the observer's head. Regarding the azimuth angle, when the sight line of the site is in the magnetic north direction, the output of the magnetic azimuth transmitter is 0 ° (magnetic north).
Are aligned as shown.

Two accelerometers are installed in the tilt detector. When the depression angle is θ, sin θ is obtained from one accelerometer and cos θ is obtained from other accelerometers. From these two values, tan θ Ask for. This is more accurate than measuring with one accelerometer.

FIG. 4 is a diagram relating to the mounting of two accelerometers 4A, 4B in the tilt detector, with axes 4a and 4b being the input axes of the accelerometers and orthogonal to each other. g indicates the direction of gravitational acceleration of the earth. The plane 4c orthogonal to this is a horizontal plane, and the angle formed by this plane and the axis 4a is the depression angle θ. Since the 4A and 4B accelerometers detect the component of gravitational acceleration according to the value of the depression angle θ, the depression angle θ can be obtained by calculating the outputs of the two accelerometers. In this embodiment, the alignment is performed on the helmet so that the sight line of the above-mentioned site and the axis 4a in this figure match.

By using two accelerometers as in this embodiment, it is possible to obtain linearity over a range of depression and elevation angles of about 90 ° and reduce the influence of inclination around the line of sight.

Another embodiment of the arrangement of the accelerometers shown in FIG. 5 in order to obtain good linearity over the entire range of depression and elevation and to suppress the error that occurs in depression and elevation when tilted around the line of sight (when the head is tilted). There is. g is the direction of gravitational acceleration, and 4c is the horizontal plane.
When the sight line of the site is placed horizontally, the input shaft 4a of the accelerometer 4A for detecting the elevation / depression angle is arranged at about 45 ° to the horizontal. As a result, good linearity can be obtained over the entire range of 0 ° to 90 °. However, if it is left as it is, an error will occur in the output of the accelerometer 4A when tilted around the line of sight. This tilt is corrected using the output of the accelerometer 4B in which the input shaft 4b is arranged so as to be orthogonal to the line of sight.

FIG. 6 shows a functional block diagram of an embodiment of the line-of-sight angle detection device according to the present invention.

The output of the magnetic azimuth oscillator 3 is converted into a signal by the signal conversion circuit 9 and sent to the arithmetic circuit 10. Two identical feedback type accelerometers 4A and 4B are attached to the tilt detector 4,
These outputs are signal-converted by the accelerometer signal conversion circuit 11 and taken into the arithmetic circuit 10. The arithmetic circuit 10 is composed of a microprocessor and a memory, and calculates a magnetic azimuth angle, a depression angle from two accelerometer outputs, and the like. Reference numeral 12 is a deviation correction setting circuit for correcting an error of the magnetic azimuth oscillator (correction difference), and the correction calculation is performed at 10. Reference numeral 13 is an interface circuit for displaying the calculated angle on the display 14 and sending it as a digital signal to the outside. The required power supply for each part is created by the power supply circuit 15.

FIG. 7 shows an embodiment in which a display is used for the site section. In this example, a small CRT 16 is used instead of the focusing screen 2b playing card 2a in FIG. 3, so that the azimuth angle, the elevation angle, etc. of the captured target can be displayed in addition to the image of the crosshair 2e. Further, by using the output angle signal to control the night-vision camera so that the line of sight of the night-vision camera and the line of sight of the present device coincide with each other, it can be used for projecting an image for nighttime use. Based on the same principle, it is possible to display various information such as distance information to the target obtained by other means, in a serious manner.

g. Effect of the invention It is easy to handle and move, and it can be used in any place regardless of topography. Moreover, the preparation time can be shortened by using a flux gate type magnetic azimuth transmitter and a feedback type accelerometer which have a short start-up time as the sensor.

Furthermore, since the entire field of view can be seen, a target searching instantaneous operation is possible, and it is easy to track a moving target.

[Brief description of drawings]

FIG. 1 is a perspective view of a helmet part of a line-of-sight angle detection device according to the present invention, FIG. 2 is a perspective view of a controller part of the line-of-sight angle detection device according to the present invention, and FIG. Optical system model diagram, FIG. 4 is a conceptual diagram showing an example of arrangement of accelerometers, FIG. 5 is a conceptual diagram showing another example of arrangement of accelerometers, and FIG. 6 is a visual line angle detection device according to the present invention. 7 is an optical system model diagram of the site portion in an embodiment using a small CRT for the site portion, and FIG. 8 is a perspective view of a visual line angle detecting device according to the prior art. 1 ... Helmet, 2 ... Site, 3 ... Magnetic azimuth transmitter, 4 ... Tilt detector, 5 ... Controller, 6 ... Cable, 7 ... Indicator, 8 ... Cable, 9 ... Signal conversion circuit, 10 ... Arithmetic circuit, 11 ... accelerometer signal conversion circuit, 12 ... error correction setting circuit, 13 ... interface circuit, 14 ... indicator, 15 ... power supply circuit, 16 ... small CRT.

Front page continuation (72) Inventor Shoichiro Shirasaka 2-16-46 Minami Kamata, Ota-ku, Tokyo Tokyo Keiki Co., Ltd. (72) Inventor Mamoru Kimura 2-16-46 Minami-Kamata, Ota-ku, Tokyo Tokyo, Inc. Inside the instrument (72) Inventor Yasuaki Sakaide 2-16-46 Minami-Kamata, Ota-ku, Tokyo Tokyo instrument inside (56) References JP-A-60-42734 (JP, A) JP-A-61-226827 (JP) , A) JP-A-2-232508 (JP, A) JP-A-3-32944 (JP, A)

Claims (3)

[Claims] 1. A helmet, a site attached to the helmet for forming an image at an infinite point on a line of sight, and a magnetic azimuth transmitter fixed to the helmet for detecting an azimuth angle from magnetic north of the line of sight. , Inclination angle detector fixed to the helmet to detect the elevation angle of the line of sight, and directing the azimuth angle and the elevation angle of the line of sight based on the output of the magnetic azimuth transmitter and the inclination angle detection angle. A line-of-sight angle detection device comprising an angle calculation means. 2. A magnetic azimuth oscillator of fluxgate type is used as said magnetic azimuth oscillator.
The line-of-sight angle detection device described. 3. The line-of-sight angle detection device according to claim 1, wherein the inclination angle detector is a feedback type accelerometer.