JPH04204112A - Detecting apparatus of speed of change in attitude of moving body - Google Patents

Abstract

PURPOSE:To enable correction of drift of a gyro output by providing an arithmetic means for obtaining a signal by subtracting from the output of a gyro a low-frequency component detected by a low-frequency component detecting means. CONSTITUTION:A yawing angular velocity signal detected by a yawing angular velocity detector 30, which is a gyro of a vibration type equipped for an automobile, is given to a microcomputer 4, with the noise of the yawing angular velocity signal removed by an interface 3. Besides, a wave reception signal of a BS antenna Ant is demodulated to a satellite broadcasting signal in a BS receiver BSR and given to a display BSD, while it is converted into an analog signal BSs therein and given to the computer 4. Azimuth and elevation motor drivers AZD and ELD rotate motors in response to step rotation instruction signals from the computer 4. In the computer 4, a signal is obtained by subtracting from an output of the detector 30 a low-frequency component detected by the computer 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a speed detection device for detecting the attitude change speed of a moving body such as a vehicle, and particularly relates to drift correction of a detection signal.

(Conventional technology) When an antenna on a moving object is always directed toward the radio wave source, tracking (reception tracking) using only a continuous roving method such as conical scanning will not provide sufficient tracking performance for rapid attitude changes of the moving object. If the signal cannot be received due to obstacles such as tunnels or buildings, tracking will not be possible.

Therefore, a technique (gyro tracking) is used in which a gyro detects a change in the attitude of a moving object, predicts and calculates the attitude deviation of the antenna (relative to the radio wave source) due to the attitude change, and corrects the antenna attitude accordingly.

According to this, when there are radio wave obstacles such as tunnels and buildings, the gyro tracking interpolates the tracking between them. Since gyro tracking is feedforward control, gyro tracking alone tends to result in poor reception, but reception tracking such as conical scan corrects gyro tracking errors through feedback control.

One of this type of attitude control device is Japanese Patent Application Laid-Open No. 64-13801.
It is presented in the publication No. In this gyro tracking, the attitude of the moving body is detected by a yaw angle detector and a pitch angle detector, and the attitude of the antenna (azimuth direction and elevation direction) is changed in response to a change in the attitude of the moving body.

There would be no problem if the gyro's output accurately represented the behavior of the moving object, and if the antenna attitude was changed accurately to compensate for the antenna attitude shift with respect to the radio wave source due to this behavior, but there is an error in the gyro's output when fishing on a boat. If this error is so large that it cannot be ignored in terms of tracking accuracy, the antenna attitude will shift by the amount of the error, which goes against the purpose of gyro tracking, and this will instead disturb reception tracking by conical scan or the like.

A typical error factor in a gyro is temperature drift at the zero point (output fluctuation due to temperature when the gyro is operating). To avoid tracking errors caused by this, it is necessary to suspend gyro tracking until the gyro temperature stabilizes.

As a method to eliminate the drift of the gyro output, (1
) Calibrate the gyro output level by the output level when the moving object is stationary. (2) Applying a bypass filter to the gyro output, and (3) Calibrating the gyro output by accurately detecting the angular velocity using another sensor and using the gyro output at that time as the angular velocity. Problem) Drift correction according to (1) above is possible only when the moving body is stationary, and it is not possible to correct the drift that changes while the moving body is moving. In (2) above, there is no guarantee that the behavior change component of the moving object and the drift component will be accurately separated, and there is also the problem that the behavior detection signal is delayed by the bypass filter, the waveform becomes dull, and the response of antenna attitude control becomes low. arise.

Although (3) can be carried out during maintenance such as inspection and repair, it cannot deal with drifts that occur thereafter or drifts that fluctuate.

The present invention aims to correct the drift of the gyro output in real time and without introducing any significant signal delay.

[Structure of the invention]

- (Means for Solving the Problems) The attitude change rate detection device of the present invention includes a gyro (30) that detects the attitude change rate of a moving object; a low frequency component (AJT) of the output (Yis) of the gyro (30); and a signal (YAR; Yas) obtained by subtracting the low frequency component (AJT) detected by the low frequency component detection means (4) from the output (Yas) of the gyro (30).
-AJT);

Note that symbols in parentheses indicate corresponding elements or corresponding matters in the embodiments shown in the drawings and described later.

(Function) There is no delay in the output (Yas) of the gyro (30) due to the low frequency component detection by the low frequency component detection means (4). The detection of the low frequency component (AJT) is delayed with respect to the output (Yis) of the gyro (30), but the detection of the low frequency component (AJT)
), that is, the fluctuation of the drift, is very gradual (low frequency) relative to the attitude change of the moving body (corresponding fluctuation of the gyro output), so this delay does not pose a problem.

Therefore, the obtained signal, that is, the attitude change rate signal (YAR=Yas-AJT) subjected to drift correction, has substantially no delay with respect to the gyro output (Yas) and also has substantially no rounding of the waveform. Since the above-mentioned drift correction is performed continuously (that is, in real time), a detection signal (VAR=Yas-A, JT) with the drift corrected can always be obtained despite fluctuations in the drift.

Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.

(Example) FIG. 1a shows an example of the present invention. This embodiment is an antenna attitude control device incorporating an embodiment of the present invention, which is mounted on the automobile shown in FIG. 2e, and controls the attitude of a BS antenna Ant for receiving geostationary satellite broadcasting. The car is equipped with a yaw angular velocity detector 3, which is a vibration type gyro.
0 is equipped with an analog signal (
yaw angular velocity signal) to the interface 3. The interface 3 subjects the yaw angular velocity signal to electrical processing such as noise removal and amplification, and supplies it to the microphone computer 4 . The microcomputer 4 includes a CPU, RAM, R
This is a computer system that includes electronic circuit elements such as an OM and a system controller, and reads the yaw angular velocity signal after digital conversion.

Interfaces 3 and 5 are connected to the microcomputer 4, and these interfaces 3,
5, an operation board 22. A BS receiver BSR, an unmass motor driver AZD, and an elevation motor driver ELD are connected.

The radio wave reception signal of the BS antenna Ant reaches the BS receiver, where it is demodulated into a satellite broadcast signal and given to the display BSD, which displays a geostationary satellite television broadcast image. The satellite broadcasting signal is also applied to an interface 5, which converts the radio wave reception signal into an analog signal BSs representing the signal level and provides it to the microcomputer 4. The microcomputer 4 is
The analog signal BSs is digitally converted and read.

Both the azimuth motor driver AZD and the elevation motor driver ELD consist of an electric circuit (motor driver) for selectively flowing forward rotation energizing current and reverse rotation energizing current to the motor, and a computer circuit (controller) mainly composed of a CPU. Each step rotation instruction signal (direction and ten rotation angles) is sent from the microcomputer 4.
In response to this, the motor of each mechanism is energized to rotate by the specified angle in the specified direction, or the microcomputer 4
The motors of each mechanism are energized to rotate at the designated speed in the designated direction in response to a continuous rotation instruction signal (direction and speed) from the rotary encoder 1 of the azimuth mechanism.
48 and elevation mechanism low reencoder 1
Count the electric pulses generated by antenna A.
nt's azimuth attitude (rotational position) data and elevation attitude (rotational position) data are updated by the attitude change due to antenna drive, and the data indicating the antenna attitude at that time is always stored in the azimuth position register AZPR and the elevation position register ELPR. Hold.

FIG. 2a shows a mechanism for supporting the BS antenna Ant and determining its attitude. This mechanism connects the BS antenna Ant to
rotationally driven in the azimuth direction (centered on the first axis Y),
It is a two-axis rotational drive mechanism that rotates in the elevation direction (centered on the second axis X).

The antenna Ant is a flat circular beam antenna with a relatively wide reception range, and is attached to the antenna bracket 110.
is fixed to.

FIG. 3 shows the directivity characteristics of the BS antenna Ant. The vertical axis is the CN ratio, and the horizontal axis is the angle between a perpendicular line passing through the center of the light-receiving surface (circular) of the antenna and a straight line connecting the center and the radio wave source (geostationary satellite). When this angle is about 8'' or less, the CN ratio shows 50% or more of the maximum CN ratio (15 dB).

Referring again to FIG. 2a, the antenna bracket 110
A horizontal shaft 113b (the center of which is the second axis X) is fixed to the angle 113a. The horizontal shaft 113b extends in a direction perpendicular to the drawing, and one end thereof is rotatably supported by a support arm 121a via a bearing (not shown). The support arm 121a is fixed to the rotating table 120. The other end of the horizontal shaft 113b is rotatably supported by another not-illustrated support arm similar to the support arm 121a via a hair ring. The other support arm (not shown) is also fixed to the rotary table 120 at a position symmetrical to the support arm 121a with respect to the cylindrical shaft 116, which will be described later.

The rotary table 120 is roughly a disk-shaped spur gear, and has a guide hole 120h in its center and a gear 120 on its side circumferential surface.
a, and to the fixed base 130 via the bearing 122,
The gear 120a is rotatably mounted around the rotation center axis (first axis) Y of the gear 120a.

A gear 144 is engaged with the gear 120a of the rotary table 120, and this gear 144 is connected to the gear shaft 145 and the reducer 14.
0 and is rotationally driven by an azimuth drive motor 141. The speed reducer 140 and the motor 141 are fixed to a support base 146 that is fixed to the fixed base 130. A rotary encoder 148 is coupled to the gear shaft 145 and generates one electric pulse for each rotation of the gear shaft 145 through a predetermined small angle. This electric pulse is applied to an azimuth motor driver AZD.

A switch 147 for detecting the azimuth home position is installed opposite to the bottom surface of the rotary table 120.
A tapered hole (-point) into which the operator of the switch 147 falls is cut on the lower surface of the switch 147 at a position facing the operator. The switch 147 is open (off) when the operator is pressed on the bottom surface of the rotary table 120, and when the taper hole faces the operator, the operator enters the hole, and the switch 147 is closed (on). : home position detection). While the rotary table 120 rotates once, the operator of the switch 147 enters the taper hole and turns on (home position detection). The open/close signal of the switch 147 is given to the azimuth motor driver AZD and also to the microcomputer 4 via the interface 5.

Referring to FIG. 2b showing an enlarged cross section taken along line IIB-nB in FIG. 2a, inside the reducer 140, the gear shaft 145
A worm wheel 143 is fixed to the worm wheel 143, and a worm 142 that meshes with the worm wheel 143 is connected to the rotating shaft of a motor 141 (FIG. 2a).

When the motor 141 rotates forward, the gear 144 rotates in one direction, and the rotary table 120 rotates in one direction around the first axis Y. That is, the antenna Ant rotates around the first axis Y in the positive direction. When the motor 141 rotates in the opposite direction, the antenna Ant rotates in the opposite direction.

The guide hole 120h of the rotary table 120 is connected to the cylindrical shaft 116.
passes through the rotary table 120, and is movable in the direction in which the first axis Y extends with respect to the rotary table 120. Although not shown, a groove parallel to the first axis Y is carved on the side peripheral surface of the cylindrical shaft 116, and a groove parallel to the first axis Y is formed in the guide hole 120h of the rotary table 120. There is a rail-shaped protrusion, and this protrusion allows the cylindrical shaft 116 to move in the direction in which the first axis Y extends with respect to the rotary table 120, but cannot rotate around the first axis Y. be. Therefore, the turntable 12
0 rotates around the first axis Y, the cylindrical shaft 1
16 also rotates around the first axis Y.

A bin 117 is fixed to the upper end of the cylindrical shaft 116, and the link arm 11 is rotatably attached to the bin 117.
The lower ends of 5 are joined. The upper end of the link arm 115 is rotatably connected to a pin 112 fixed to the angle 111 of the bracket 110.

The placket 110 is attached to the horizontal axis 11 from the angle 113a.
3b in the horizontal direction perpendicular to the extending direction (perpendicular to the plane of the paper in FIG. 2a), so when the cylindrical shaft 116 moves upward in FIG. 2a, the antenna Ant
rotates counterclockwise (rotates upward) about the horizontal axis 113b, and when the cylindrical shaft 116 moves downward, the antenna Ant rotates clockwise (rotates downward).

On the outer peripheral surface of the lower half of the cylindrical shaft 116, a gear 116a, which is not spiral-shaped but ring-shaped, is carved. Each of the crests and troughs of the ring-shaped gear 116a is parallel to the direction perpendicular to the first axis Y. A gear 154 meshes with this ring-shaped gear 116a.

Referring also to FIG. 2c, which shows a large cross-section taken along the line NC-NC in FIG. 1a, the gear shaft 155 of the gear 154 has a
0 worm wheel 153 is fixed. A worm 152 meshing with a worm wheel 153 is connected to a rotating shaft of an elevation drive motor 151 (FIG. 2a). The speed reducer 150 and the motor 151 are fixed to a support base 146 that is fixed to the fixed base 130.

When the elevation drive motor 151 rotates forward, gear 1
54 rotates clockwise in FIG. 2a to form the cylindrical shaft 11.
6 moves upward, and the antenna Ant rotates clockwise (rotates upward). When the motor 151 rotates in the opposite direction, the antenna A
nt rotates counterclockwise (rotates downward).

The link arm 11 is moved upward and downward by the cylindrical shaft 116.
5 is applied with a rotational force about the bin 117, and the link arm 115 rotates about the bin 117. During this rotation, so that the rotation of the link arm 115 is not hindered,
A groove 118 is cut into the upper end of the cylindrical shaft 116, as shown in FIG. 2d.

As described above, the gear 154 meshes with the gear 116a of the cylindrical shaft 116, and each of the peaks and valleys of the gear 116a forms a ring that goes around the side circumferential surface of the cylindrical shaft 116. Since it is parallel to the first axis Y, the cylindrical shaft 116 is not restricted in rotation by the gear 154 and rotates about the first axis Y both when the gear 154 is stationary and when it is rotating. It can rotate, and this rotation itself causes the cylindrical shaft 116 to turn into gear 15.
It does not go up or down with respect to 4.

Referring to FIG. 2c, a cam plate 156 is fixed to the gear shaft 155 of the gear 154. As shown in FIG. This cam plate has a step on its outer peripheral edge.

An upper limit switch 158 is provided on the outer peripheral surface of this cam plate 156.
and the lower limit switch 159 are facing each other, and when the elevation rotation angle of the antenna Ant is within a predetermined range, the operators of the switches 158 and 159 are opposite to the cam plate 1.
Since it faces the small radius outer peripheral surface of switch 15
8.159 are both open (off). When the antenna Ant rotates clockwise and reaches the clockwise rotation mint position (upward limit), the taber surface of the cam plate 156 that switches from the small radius outer circumferential surface to the large radius outer circumferential surface presses the operator of the switch 158. Switch 158 is turned closed (on). When the antenna Ant rotates in the direction of the half-hour hand and reaches the limit position (downward limit) of rotation in the direction of the half-hour hand, the Taber surface of the cam plate 156 that switches from the small radius outer circumferential surface to the large radius outer circumferential surface presses the operator of the switch 159. This turns switch 159 closed (on). switch 15
The opening/closing signals of 8 and 159 are from the elevation driver E.
The signal is applied to the LD and also to the microcomputer 4 via the interface 5.

A rotary encoder 157 is connected to the worm 152, and the rotary encoder 157 is connected to a rotary encoder 157.
Generates pulsed electrical pulses.

This electric pulse is generated by the elevation motor driver ELD.
given to.

As described above, the reducer 140 and the motor 141 for rotationally driving the antenna Ant around the first axis Y, and the horizontal axis 113b (, the second axis ), a reducer 150 and a motor 151 are both mounted on the fixed base 130
Since the motors 141 and 151 are fixed to
No sliding connection means are required for supplying power to the .

Referring to FIG. 2a, the converter Conv is attached to the antenna bracket 110 and converts the 12 GHz band satellite broadcast radio waves received by the antenna Ant into I GHz band B.
Convert to S-IF. The converted signal is transferred to the cable 16
1 to the rotary joint 160 and to the BS receiver BSR (FIG. 1a).

However, the converter Co fixed to the bracket 110
Since nv rotates around the first axis Y and the horizontal axis 113b together with the antenna Ant, the signal line and power receiving line of the converter Conv and the BS receiver BSR in the fixed part
It is necessary to connect the signal line and the feed line through a sliding connection means.

In this embodiment, since the elevation rotation range of the antenna Ant about the horizontal axis 113b only needs to be 360 degrees or less, the electric cable 161 consisting of the signal line and the power receiving line of the converter Conv is relatively flexible. In addition to being highly flexible, the shaft has a length that allows for rotation of 360 degrees or more, and the wire is connected to the rotary joint 160 by passing through the thick part of the cylindrical shaft 116. The rotary joint 160 has a BS receiver BS
An electrical cable 162 from R is connected, and this rotary joint 160 connects cables 161 and 16.
The two leads to be electrically connected to each other are electrically connected to each other despite relative rotation about the first axis Y.

With respect to the rotation of the antenna Ant about the horizontal axis 113b, the cable 161 swings approximately about the bin 117.

Thus, in this embodiment, only one set of sliding connection means (port to tally joint 160) is used.

The elevation drive motor 151 of the elevation mechanism (150, 151) rotationally drives the drive gear 154, but since the cylindrical shaft 116 reciprocally driven by the drive gear 154 slides with respect to the rotary table 120, the rotary table 1
20 and an azimuth mechanism (144,
140°141) is the elevation mechanism (150°1
51) and is not driven by the elevation mechanism (1
50,151). The objects supported by the elevation mechanism (150, 151) are essentially the BS antenna Ant, the BS converter Conv, the link arm 115, and the cylindrical shaft 116, and since the load is small, the inertial force is small, and the second axis (X) is Centered on B
Azimuth driving and elevation driving of the S antenna Ant can be performed at relatively high speed, and positioning can be performed with relatively high precision.

Referring to FIG. 4, the operation board 22 has an antenna A.
nt azimuth data (hereinafter referred to as azimuth data), elevation (downward)
Corner data (hereinafter referred to as elevation data).

LC for displaying reception level and various messages
D (Two-dimensional liquid crystal display board)23. A START key 24 for instructing automatic attitude control of the antenna 30.
Stop (STOP) key 25 for instructing to stop automatic attitude control of antenna Ant. Up key (U key) for manual attitude control 26. Down key (D key) 27
．． A right key (R key) 28 and a left key (L key) 29 are provided.

FIG. 5 shows an outline of the control operation of the microcomputer 4. A power supply circuit (not shown) is connected to the vehicle battery when the vehicle ignition key is in the engine operating position (ignition key switch on).
A predetermined voltage is applied to each part of the electric circuit shown in FIG. 1a. Note that a battery voltage is also applied to the motor drivers AZD and ELD for energizing the motor.

When a predetermined voltage is applied to itself, the microcomputer 4 executes "system initialization" (from subroutine 1' onwards, the words "step" and "subroutine" are omitted in parentheses, and only the numbers assigned to them are written). , internal register.

The timer, counter, etc. are set to the contents determined in the standby state (initial state), and a signal specifying non-operation (de-energization) is set to the output boat. Additionally, an internal timer of 9°amsee is started, and the timeout of the timer (9,
The internal interrupt process (FIG. 1b) that is activated upon completion of timing of 6m5ec is enabled. Then, "initialization of antenna posture" is executed. In this case, the antenna Ant is set at the home position (switch 147 on) in the azimuth direction and at the limit position (downward limit position: switch 159 on) of half-hour hand direction rotation (downward rotation) in the elevation direction. Set the posture origin and register the posture register (azimuth position: register AZPR).
/Elevation position: Clear register ELPR).

Furthermore, since internal interrupt processing (Fig. 1b) is enabled, when the internal timer of 9.6m5ec times out, the internal interrupt processing shown in Fig. 1b is executed, and 9.6m5ec is
Since the internal timer of 5ec is restarted, the internal interrupt processing shown in FIG. 1b is repeated every 9.6a+sec thereafter.

When the microcomputer 4 receives the Ready signal from both motor drivers AZD and ELD, the microcomputer 4 outputs 5T.
A loop is formed to execute the manual operation process of step 4 (hereinafter referred to as S) until the ART key 24 is turned on.

The manual operation process will be explained with reference to the flowchart shown in FIG. When the U key 26 is operated, the microcomputer 4 proceeds from S30 to 331, where it turns on (closes) the upper elevation limit switch 158.
/ Check OFF (open). If the switch 158 is on (closed), the attitude of the antenna Ant in the elevation direction is at the upper limit of the elevation angle, and further upward movement is impossible. Instructs the driver ELD to execute a 15 step upward shift process. Further, when the D key 27 is operated, the process advances from 333 to 334, where it is checked whether the lower elevation limit switch 159 is on (closed) or off (open). If the switch 159 is on (closed), the attitude of the antenna Ant in the elevation direction is at the lower limit of the depression angle, and no further downward movement is possible.
5 to elevation motor driver ELD, 1s
Instructs execution of jep downward shift processing.

When the R key 28 is operated, the microcomputer 4 proceeds from 336 to 337, where it instructs the azimuth motor driver AZD to shift to the right by 15 steps (clockwise rotation: forward rotation), and presses the L key 29. If there is an operation, the process proceeds from 338 to 339, where the azimuth motor driver AZD is instructed to shift left by 15 steps (rotation in the direction of the half-hour hand: reverse rotation).

Referring to FIG. 6 again, the MicroNinputer 4
Motor driver AZD in S40.

1 5 step right shift 1s + ep left shift by ELD.

Wait for a 15-step up shift or a 5-lep down shift to be executed, and at 341, the motor driver AZ
D. Read Az data and EL data transferred from ELD. Furthermore, in S42, the reception level B S
s@: Read and store in register L1, and in 343, Az data, EL data, and reception level BSs of register L1 are displayed on LCD 23.

The microcomputer 4 includes S4 and S5 (Figure 5).
, when the 5TART key 24 is turned on, S
In step 5, "initial search JS5" shown in FIGS. 7a, 7b, and 7c is executed.

[The contents of the initial search JS5 will be explained with reference to FIGS. 7a, 7b, and 7C.First, the concept of the initial search JS5 will be explained with reference to FIG. While monitoring the BSs, change the attitude of the antenna Ant in the elevation direction from the position indicated by the data in the register ELS, first upward by 10' (10 steps), then from the position indicated by the data in the register ELS,
20" (20 steps) downwards, then register EL
It changes from the position +11° indicated by the data in S to the upper limit position, and finally from the position -216 indicated by the data in the register ELS to the lower limit position. Each step 16 is changed one step at a time, and each one step change scans one rotation in the azimuth direction.

One rotation scan in the azimuth direction is also changed in steps of 1 degree. For each step drive in the azimuth direction,
Also, for each step drive in the elevation direction, the received signal level BSs of the receiver BSR is read, and it is checked whether it is equal to or higher than the threshold value 782 for determining whether reception is possible, and if it becomes equal to or higher than TH2, then Initial search JS5 ends.

To explain more specifically with reference to FIG. 7a, first, it is checked whether the data in the register ELS indicates the elevation origin (0) (s5oa). In this embodiment, the register ELS is allocated to an area of the memory in the microcomputer 4, so when the computer 4 is powered off, the next time the computer 4 is powered on, the contents of the register ELS will be zero data. It has become.

In this case, "In the system initialization JSI, the attitude of the antenna Ant is the origin (azimuth position: 0, elevation position: 0). Therefore, in this case, the computer 4 instructs the elevation driver ELD to The driver ELD instructs the elevation drive to the midpoint (the midpoint between the upper and lower limits). In response to this instruction, the driver ELD drives the antenna Ant to the midpoint of the elevation, and provides position data of the midpoint of the elevation (EL data) to the computer 4.The computer 4 writes this position data (midpoint) to the register ELS (S5
0b).

"Register E when proceeding to initial search J (35)"
When the LS has data other than the origin, this means that the antenna drive below "Initial Search J (S5)" has already been executed once since the power was turned on to the system shown in Figure 1, and for example, The elevation position when the reception level is suitable is written in 513a, which will be described later.In this case, the data in the register ELS is not updated.

Next, in 350, the Az data at that time is stored in registers A1 and A2, and the EL data is stored in register E2.
Then, ELS+10 is stored in register E1.

After this, the reception level is read at 352. When the value is equal to or higher than the predetermined level THI, the microcomputer 4 immediately returns to the main routine from S53 (ends the initial search);
If it is less than 354, the process proceeds to step 354 and the attitude of the antenna Ant is changed. In this attitude change, first, if the soil elevation upper limit switch 158 is not on and the elevation position E2 has not reached the upper limit El of the first search area, the process proceeds from S54 to 555a-hS56, where the elevation motor driver It instructs ELD to shift up by 1 sleep and increments the value of register E2 by 1 at 357. Upon receiving the shift end signal from the motor driver ELD, the microcomputer 4 executes [azimuth scanning] AZS.

[In azimuth scanning JAZS, first read the received signal level BSs (358), check whether it is TH2 or higher (359), and if it is TH2 or higher, "
Finish "Initial Search".

If it is less than 782, it is checked whether the azimuth home position switch 147 is on (home position), and if it is not on, the azimuth position A2 is set to 1'' left of the initial position (Az data when entering "initial search JS5"). (362), if not, instructs the driver AZD to shift by 15 steps to the right, and increments the current azimuth position data A2 by 1 (364). Return to 35B again and repeat the above while monitoring the reception level. When the home position switch 147 is turned on, the antenna is rotated once in the azimuth direction to the left (361). This is to avoid continuous clockwise rotation of two or more rotations.

Azimuth scan (AZS) rotates once in the right direction (from A1 to A
l-1: To be exact, when the clockwise rotation from A1 to A1 becomes one rotation, it returns to 352 and 15te in the elevation direction.
Perform a p-up shift.

Reference is now made to Figure 7b. In this way, register E
From the LS elevation position to the position 10@ above (if the upper limit is reached by then, the upper limit will be reached), even if the azimuth direction is searched in the first area around the entire circumference, the reception level B
If Ss does not become TH2 or more, then register ELS
In order to search from the elevation position of 206 to the lower position, first instruct the register ELS to shift downward to the elevation position 365), then in 550b, the Az data at that time is stored in registers A1 and A2.
and store the EL data in register E2, ELS-20
is stored in register E1. Then, every time the motor is driven down by 15 steps in the elevation direction, a search (AZS) in the azimuth direction is performed. In this case, the reception level BSs is read every time it is shifted to the right by 15 steps in the azimuth direction, and every time it is shifted down by 15 steps in the elevation direction, and if it is TH2 or higher, the initial search ends there, but the register ELS is Even when searching the second small area at 120° from the elevation position, the reception level BSs
is not TH2 or more, the right half of Fig. 7c (S66
-AZS), the third small area from the elevation positioner 116 of the register ELS to the upper limit is searched. If the value is still not greater than TH2, the fourth small area from the elevation position t-21' of the register ELS to the lower limit is searched in the process shown in the left half of FIG. 7c (S67 to AZS).

If the reception level BSs does not become equal to or higher than TH2 even after completing the search for this fourth small area, it means that an appropriate reception level was not obtained even though the entire range of antenna postures was searched.

Therefore, in this case, proceed from 554d to 555d and L
``Unreceivable'' is displayed on the CD 23 and the process returns to 83 of the main routine (FIG. 5).

"In the initial search JS5, the reception level BSs is the predetermined value 78.
When searching for the attitude of antenna Ant that is 1 or more, the fifth
In S6a of the figure, the yaw angular velocity Yas detected by the yaw angular velocity detector 30 is read. Then, the content AJT of the drift correction value register AJT is subtracted from the yaw angular velocity Yas, and the difference is written into the speed register YAR (S6b). Then, the data YAR of the speed register YAR (the sign specifies the motor rotation direction, and the absolute value of the numerical value specifies the speed)
Transfer to azimuth motor driver AZD (6C)
.

The drift correction value register AJT contains “
The drift amount AJT calculated in internal timer interrupt processing J 3200 is written. First, in the system initialization JSI of FIG. 5, the 9.6m5ec timer is started and the [internal timer interrupt processing] 5200 to be executed in response to the timeout of this timer is enabled, and the first
The [internal timer interrupt processing J 3200 shown in FIG.
Executed with ec.

The contents of "internal timer interrupt processing J 5200" for calculating the drift correction amount AJT will be explained with reference to FIG. 1b.

Proceeding to this, Micro Convenience Store 1 and 4 are 9.6
The m5ec timer is restarted L (201), and the detection output Yas of the yaw angular velocity detector 30 is digitally converted and read (3202). Next, the read value Yas is written to the accumulator register yy (0) (3203), and 1 is written to the operation execution count register j (S204). Then, first perform the first low-pass filtering operation (32
05).

Next, the contents of register J are incremented by 2 (32
06), a second low-pass filtering operation is performed using the first calculated value (S205). Next, the contents of register j are incremented to 3 (3206), the low frequency component yy(2) obtained in the second calculation is written to the drift correction amount register AJT (S208), and the main routine (interrupt processing Go back to the previous step).

The above-mentioned low frequency component, that is, the drift correction amount AJT(yy
Output Y of the yaw angular velocity detector 30 for calculating (2))
As reading of as is performed at a cycle of 9.6m5ec,
The sampling frequency of the above-described low-pass filtering process is 104 Hz. The multiplication coefficients for the low-pass filtering operation are marked outside the block in Figure 1b.

A calculation diagram of the above-described low-pass filtering process is shown in FIG. 1C. The delay time of the delay device shown in FIG. 1C is 9.6 m5ec.

Based on the values of the multiplication coefficients shown in FIG. 1b and the sampling frequency described above, the cutoff frequency is set at 0.05 Hz in this embodiment. This results in 0.0
A fluctuation component of 5 Hz or less (with a period of 20 seconds or more), that is, a drift component, is obtained as A J T (y Y (2)).

As mentioned above, AJT is data indicating the amount of drift component, and azimuth motor driver AZD has YAR=Y
a s - A J T or yaw angular velocity detector 30
The value obtained by subtracting the drift component from the detected value is transferred.

The azimuth motor driver AZD rotationally biases the azimuth motor 141 so as to rotationally bias the antenna Ant to the right when the sign of the data YAR is negative (the car rotates counterclockwise) and to the left when the sign is positive. The antenna Ant monitors the pulses generated by the rotary encoder 148.
The iUt control of the azimuth motor 141 is performed so that the rotational speed of the azimuth motor 141 matches the speed designated by the MAR.

Azimuth motor dry data YAR with S6c/<AZ
When the data is transferred to D, the microcomputer 4 starts a T1 timer (internal timer), although it is not shown in the drawing. And S6c.

314, 317, etc., repeatedly with a period T1, 313. When returning to S6a from S16 or 317, wait for the T1 timer to time out, and when the time has elapsed, proceed to 36a.

Microcomputer 4 receives the reception level BS at the next 310.
Read s and write to register L1, antenna Ant
After reading Az data and EL data indicating the attitude of the motor driver AZD and ELD, these data are displayed on the LCD 23.

(I) 513 compares the reception level BSs at this time, that is, the value of the register L1, with the predetermined level THI, and as long as the value of the register L1 is equal to or higher than the predetermined level 781, S 6 a-4S 6 b-* S 6 c-=S8→
By repeating the loop S10→S13→S6a→..., the yaw angular velocity Ya detected by the yaw angular velocity detector 3o
Attitude control processing (1) of the antenna Ant based on s is executed.

That is, while the reception level BSs is equal to or higher than the first set value THI, if there is a change in the yaw angular velocity Yas, the attitude of the antenna Ant is corrected by the amount corresponding to the change. While this is continuing, if the 5TOP key 25 is turned on, this is read in S8 and 83 (83) of the flow shown in FIG.
Return to standby state).

The above-mentioned loop (S6a-=S6b-*) executes control for changing the attitude of the antenna Ant in conjunction with changes in the yaw angular velocity Yas when the reception level BSs is high.
S6cmh38-=S10→S13→S6a→...)
, the reception level BSs, that is, the register L1
When the value of becomes less than the predetermined level THI, the microcomputer 4 detects this in S13, and changes from 313 to 314.
Step 1, "reception tracking" S14 is executed. When this is completed, the reception level BSs is further read (15) and compared with the reception lower limit level TH2, which is lower than the th level THI (16). At 316, when the reception level BSs is less than the reception lower limit level TH2, the microcomputer 4
The process advances to step 7 and a "tracking search" S17 is executed.

(n) "Reception tracking" with reference to Figures 8a and 8b.
The contents of S14 will be explained.

First, the concept will be explained with reference to FIG.

FIG. 11 is a conceptual diagram showing a scanning position developed in a plane when the antenna is conically scanned over a minute range.

This conical scanning of a minute range rotates the main beam of the antenna Ant (1 → 2 → 3 → 4 → 5 → 6 → 7 → 8 → 1 →
...), and if the target radio wave source is at the center of rotation of the antenna beam, the reception level will be constant during this rotation (scanning), but if the target radio wave source is deviated from the rotation center of the beam, the reception level will be constant. This method takes advantage of the phenomenon in which the maximum value appears as a result of fluctuations during scanning. In Figure 11, the squares are in the elevation direction (U/D) and in the azimuth direction (R/L).
), each point 1°2.3,4,
5, 6.7 and 8 are the projection points of the main beam (center) of the antenna Ant. 0 is the rotation center of the antenna beam (direction in the attitude just before starting scanning), and the arrow indicates the shift direction of the attitude of the antenna Ant. show. Further, it is assumed that there is an isotropic antenna (isotropic pyroelectric wave source) at point a. Hereinafter, "reception tracking" S14 from a state where the antenna Ant is directed to point 0 will be explained with reference to FIGS. 8a and 8b and FIG. 11.

1), drive the antenna Ant from the starting point 0 to the point 157
0 to 573), the reception level was memorized at point 1 (S
84) After that, shift 2 steps in the azimuth direction and shift 1 step downward in the elevation direction to direct to point 2. 374) Store the reception level BSs at point 2 (384)
.

2) 6 Next, shift one step to the azimuth direction cloth.

Shift 2 steps downward in the elevation direction and direct to point 3 375) Store the reception level at point 3 (S84)
.

3) First, shift one step to the left in the azimuth direction.

Shift 2 steps downward in the elevation direction and direct to point 4 (376) Store the reception level at point 4 (3114)
).

4) Next, shift 2 steps to the left in the azimuth direction.

Shift one step downward in the elevation direction to point toward point 5 (577) Store the reception level at point 5 (384)
.

5) 8th, shift 2 steps to the left in the azimuth direction.

Shift one step in the elevation direction to point 6 578) Store the reception level at point 6 (384)
.

6) Next, shift one step to the left in the azimuth direction.

Shift 2 steps in the elevation direction to point 7 579) Store the reception level at point 7 (384)
.

7) 9 Next, shift one step to the right in the azimuth direction.

Shift 2 steps in the elevation direction and direct to point 8 (380) Store the reception level at point 8 (S84)
.

As described above, one conical scan is completed, and the reception levels BSs of all points (8 points) are written in the registers FOR1 to FOR8.

8) 0 Next, the reception levels from point 1 to point 8 are compared to find the point with the highest reception level (S87-91).

9), and determine the attitude of the antenna Ant so that the center of rotation of the antenna beam is aligned with the obtained maximum point (39
2).

When point a shown in Fig. 11 is the position of the radio wave source, the magnitude of the reception level is as follows: point 1> point 2> point 8> point 3> point 7> point 4> point 6> point 5 Therefore, the highest point of reception level is point 1. Therefore, the attitude of the antenna Ant is set so that the directional center of the antenna beam is aligned with point 1.

As mentioned above, in the reception tracking J314, one cycle of conical scanning of a minute range is performed around the center axis (point 0) of the original antenna beam, and the highest point of the reception level is detected. The attitude of antenna Ant is set so that the central axis of the antenna beam is placed at Attitude control is performed in such a manner that the antenna Ant moves together with the source, and the antenna Ant tracks the radio wave source.

In addition, since S6a, S6b, and S6c are executed immediately before the above-mentioned single conical scan and attitude setting (II) (see Fig. 5), the above-mentioned attitude control (I) is performed while (II) is being repeated. is also being executed.

When one conical scan and attitude setting (n) described above are completed, the reception level is not necessarily equal to or higher than THI. When the reception level becomes TH1 or higher with conical scanning and attitude setting (II), only the above-mentioned attitude control (I) is executed, but if the reception level becomes 782 or higher with conical scanning and attitude setting (n) as well, then If not, the microcomputer 4 executes "tracking search" S17.

(m) "Tracking search" 317 in Figures 9a and 9b
FIG. 12 is a schematic diagram for explaining the processing concept of "tracking search" 317.

Referring to these drawings, S]00 is the initial setting, and the state in which the antenna Ant is directed to the dot shown in FIG. 12 is assumed to be when TSC=0.

1) Check whether the TSC value is 4 or less at 3101.

As long as the TSC value is 4 or less, proceed to 3102 5102
Check the status of the switch 158, and if it is not on, 51
At 03, the motor driver ELD is instructed to shift up by one step. This is the scan from points 0 to 5 in FIG. If the TSC value is 5 or more in 5101, the process advances to 5104.

2) Check whether the TSC value is 54 or less at 5104. As long as the value of TSC is 54 or less, the process advances to 5105 and instructs the motor driver AZD to shift right by 1 step. This is the scan from points 5 to 55 in FIG. 31
If the TSC value is 55 or more in 04, the process advances to 5106.

3) Check at 3106 whether the TSC value is 64 or less. As long as the value of TSC is smaller than 65, the process advances to S]07, and the state of the switch 159 is checked in S]07, and if it is not on, the motor driver ELD is instructed to shift down by one step in S]07. This is the scan from points 55 to 65 in FIG. If the TSC value is 65 or more in 3106, the process advances to 5109.

4) Check whether the TSC value is 164 or less at 5109. As long as the value of TSC is 164 or less, the process advances to 3110 and instructs the motor driver AZD to shift left by 1 step. This is the scan from points 65 to 165 in FIG. 3109 and the TSC value is 165 or more, 31
Proceed to 11.

5) Check whether the TSC value is 174 or less at 5lll. As long as the TSC value is 174 or less, proceed to 5112, check the state of the switch 158 in 5112, and if it is not on, take one step to the motor driver ELD in 5113.
Instructs to shift up. This is the point 165-1 in Figure 12.
75. 3111 and TSC value is 175
In the above cases, proceed to 3114.

6) Check whether the TSC value is 224 or less at 5114. As long as the value of TSC is 224 or less, the process advances to 3115 and instructs the motor driver AZD to shift right by 1 step. This is points 175-225 in Figure 12 (previous point 5)
This is a scan of If the TSC value is 225 or more in 5114, the process advances to 5116.

7) As long as the value of TSC is 229 or less in 5116, the process advances to 5117, and the state of the switch 159 is checked in 5117, and if it is not on, the motor driver ELD is instructed to shift down by 1 step in 511g. This is point 2 in Figure 12.
25 (previous point 5) to point 230 (previous point 0).

8) When the TSC value is 230 or more in 5116, and when the shift is completed by instructing the shift as described above, execute 5120 to read the reception level, and in 3121 if it is TH2 or more. If it is TH2 or more, the process returns to the main routine (FIG. 5).

If it is less than 782, the reception level BSg is read again in 3123, and in 5124 it is checked whether it is higher than the second set value TH2.
Update the value of C to a value larger by 1 and proceed to Sl Old.

By the above processing of 5lot-3125, reception level B
Until Ss becomes equal to or higher than the second set value TH2, as shown in FIG.
3. ...230(0) in this order, and it is checked whether the reception level has become TH2 or higher at each point. 230 points with less than 782
When reaching (b=0), that is, returning to the original starting point, "TSC is reset to 0 at 3119, and the same search scan is performed because it is turned on again.

During such a search scan, each time a point is reached,
3122 is the motor energizing parameter set (S6a, S6
b, the same as the contents of S6c) is executed, and the yaw angular velocity Y
Since the attitude change corresponding to as is executed, the position of the base point (b=o) does not change while there is no change in the attitude of the vehicle, but
When there is a change in the attitude of the vehicle, the base point automatically shifts accordingly, but the search scanning range (FIG. 12) with respect to the base point does not change.

For a leap whose radio waves are blocked by an obstacle, the above-mentioned "search scan" S17 is repeated, and if the attitude of the vehicle changes during that time, the base point of the search scan is shifted in conjunction with the change. Therefore, when the radio wave is interrupted, the search scan of the locus shown in Fig. 12 is repeated with the position of the beam center axis of the antenna just before that as the base point (b = 0: Fig. 12) until the radio wave is received. If there is a change in the vehicle's attitude during that time, the reference point will shift in conjunction with the change in attitude of the vehicle.

To summarize here, (1) While the reception level BSs is equal to or higher than the second level TH1, the antenna A
nt's attitude is changed.

(II) When the reception level BSs is less than THI and more than TH2, in addition to (1) above, a conical scan and an antenna attitude change to the optimum pointing direction obtained thereby are performed. (m) When the reception level BSs is less than the second level TH2, in addition to the above (1), a tracking search (FIG. 12) is performed over a wider range than the conical scan.

In the above embodiment, the microcomputer 4 calculates the low frequency component, that is, the drift component AJT by low-pass filtering calculation, and the yaw angular velocity detector 3 calculates the low frequency component, that is, the drift component AJT.
Yaw angular velocity signal YAR-Ya obtained by subtracting the drift component AJT from the output Yas of 0 to remove the drift component.
AJT is obtained, but such signal YAR is sent to an equivalent electric circuit (
(analog filter).

From the above description of the embodiments, it will be easily understood that the present invention can be applied not only to a yaw angular velocity detection gyro, but also to a roll angular velocity detection gyro and a pitch angular velocity detection gyro.

〔Effect of the invention〕

As described above, according to the present invention, the low frequency component detection means (4)
There is no delay in the output (Yas) of the gyro (30) due to the detection of low frequency components by the gyro (30). Low frequency component (AJT)
Although the detection of is delayed with respect to the output (Yas) of the gyro (30), the fluctuation of the low frequency component (AJT), that is, the fluctuation of the drift, is delayed relative to the attitude change of the moving object (the corresponding fluctuation of the gyro output). This delay is not a problem since it is very gradual (low frequency).

Therefore, the obtained signal, that is, the attitude change rate signal (YAR=Yas−T) subjected to drift correction, has substantially no delay with respect to the gyro output (Yas) and also has substantially no rounding of the waveform. The above drift correction is performed continuously (that is, in real time), so
Despite drift variations, a drift-corrected detection signal (VAR=Yas-AJT) is always obtained.

[Brief explanation of the drawing]

FIG. 1a is a block diagram mainly showing the configuration of an electric circuit section of an antenna attitude control device incorporating an embodiment of the present invention. FIG. 1b is a flowchart showing the processing contents of the microcomputer 4 shown in FIG. 1a to extract a low frequency component from the yaw angular velocity detection signal Yas. FIG. 1c is a calculation block diagram for performing the low frequency component extraction process shown in FIG. 1b. FIG. 2a is a longitudinal sectional view of the antenna support mechanism of this embodiment. FIG. 2b is an enlarged sectional view taken along the nB-IIB line in FIG. 2a. FIG. 2c is an enlarged sectional view taken along the line nc-nc in FIG. 2a. FIG. 2d is an enlarged perspective view showing the top surface of the turntable 120 shown in FIG. 2a. FIG. 2e is a perspective view showing the antenna Ant shown in FIG. 2a mounted on an automobile. FIG. 3 is a graph showing the radio wave reception characteristics of the antenna Ant shown in FIG. 2a. FIG. 4 is an enlarged plan view of the operation board 22 shown in FIG. 1. FIG. 5 is a flowchart showing an outline (main routine) of the control operation of the microcomputer 4 shown in FIG. FIG. 6 is a flowchart showing the contents of the manual operation j4 shown in FIG. Figures 7a, 7b and 7c are similar to those shown in Figure 5.
5 is a flowchart showing the contents of "Initial Search" 5. Figures 8a and 8b show "reception tracking" shown in Figure 5.
14 is a flowchart showing the contents of step 14. FIGS. 9a and 9b are flowcharts showing the contents of "tracking search" 17 shown in FIG. FIG. 10 is a schematic diagram showing the transition of the pointing direction of the antenna Ant due to the "initial search" 5 shown in FIG. 7. FIG. It is a graph showing the amount of change, where the horizontal axis shows the azimuth direction and the vertical axis shows the elevation direction. FIG. 12 is a graph showing the amount of attitude change of the antenna Ant due to the "tracking search" 17 shown in FIGS. 9a and 9b, where the horizontal axis shows the azimuth direction and the vertical axis shows the elevation direction. 3: Interface 4: Microcomputer (low frequency component detection means. Calculation means) 5° interface Ant + antenna Conv: BS converter BSR: BS receiver BSD: CRT AZD: Azimuth motor driver ELD: Elevation motor driver 10 : Azimuth rotation drive mechanism 20゛ Engineering rotation rotation drive mechanism 22: Operation board 30: Yaw angular velocity detector (gyro) 110: Antenna bracket 111.113a, 114a Angle 112, Bin 113b: Second axis 112: Bin 113b: Second Axis Y, 1st axis
115° link arm 116: Cylindrical shaft 116a: Ring gear 120h guide hole 117: Pin 118, split groove 120° Rotating table 120a: Gear 121a: Support arm 122°
Bearing 130; Fixed base 140: Reducer 141: Azimuth drive motor 142: Worm 143: Worm wheel 144
° Gear 145: Gear shaft 146: Support stand 147: Azimuth home position switch 148: Rotary encoder 150: Reducer 151 ° Elevation drive motor 152: Worm 153 ° Worm wheel 154
: Gear 155: Gear shaft 157 Rotary encoder 158: Elevation upper limit switch 159: Elevation upper limit switch 160 "Rotary joint 161.162: Cable Patent applicant Aisin Seiki Co., Ltd. and one other agent Patent attorney Nobuaki Sugi ,・ , 4. No. 1b A21=-1,99988995 A22=1.00000000 B21=-1,99511014 B22 0.995120369 At first XRtlJ1m, Z11=O, Z21=O, Z
12=O&Z22=0Figure 2bFigure 20Figure 2dFigure 20Figure 3Figure 4Figure 5Figure 6Figure 7bFigure 8b-87-9b Figure 1 Bone-0-+φ- 1

Claims (1)

[Scope of Claims] A gyro that detects the attitude change speed of a moving body; a low frequency component detection means that detects a low frequency component of the output of the gyro; and a low frequency component detected by the low frequency component detection means from the output of the gyro. An apparatus for detecting an attitude change speed of a moving body, comprising: arithmetic means for obtaining a signal obtained by subtracting .