JPS6042614A - Correcting device of tilt angle sensor - Google Patents

Abstract

PURPOSE:To correct an error due to the acceleration or deceleration of a vehicle by providing a vehicle speed sensor and a correcting arithmetic circuit which corrects the error due to the acceleration or deceleration of the vehicle speed according to a specific expression and outputs a corrected tilt angle. CONSTITUTION:A correcting device corrects a detection error in tilt angle due to the acceleration or deceleration as to a tilt angle sensor 2 which detects and outputs the relative angle to the vehicle body with a weight suspended from the vehicle body. This correcting device consists of the vehicle speed sensor 1 which detects and outputs the actual speed of the vehicle body and the correcting arithmetic circuit which inputs the output G0 of the tilt angle sensor 2 and output (v) of the vehicle speed sensor 1, and outputs the corrected tilt angle G by correcting the error due to the acceleration or deceleration according to the equation of G=G0+arctan{v(dtheta/dt)/g}. For example, the correcting arithmetic circuit consists of an AD converter 3, microcomputer 4, driver 5, a display device 6, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention detects the tilt angle of a vehicle using a tilt angle sensor correction device, more specifically, a weight (1) Correcting the error of the tilt angle sensor due to vehicle acceleration 1 The present invention relates to a correction device for a tilt angle sensor.

Conventionally, inclination angle sensors mounted on vehicles have used the principle of a pendulum, and have detected the inclination angle based on the relative angle between the direction of gravity acting on the weight of the pendulum and the vehicle body.

In such a tilt angle sensor, when the vehicle speed changes such as during acceleration or deceleration, an indication that the vehicle is tilted may be displayed even if the vehicle is not tilted in the longitudinal direction. This is because the weight that makes up the tilt angle sensor detects the direction of gravity, and the force due to acceleration and deceleration in the longitudinal direction of the vehicle acts on this weight. This is because it is determined to be tilted.In this way, there is no way to correct it with a mechanical tilt angle sensor, and the only countermeasure that can be taken is to strengthen the damper.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a correction device for a tilt angle sensor that can correct errors caused by acceleration and deceleration of a vehicle in a tilt angle sensor that electrically detects a tilt angle based on a deflection angle of a weight. .

(2) In order to achieve the above object, the tilt angle sensor correction device according to the present invention detects and outputs the relative angle with the vehicle body using a weight suspended from the vehicle body. 11 to correct detection errors! In the tilt angle sensor correction device, a vehicle speed sensor that detects and outputs the actual vehicle speed of the vehicle, an output (CO) of the tilt angle sensor, and an output (V) of the vehicle speed sensor are connected, and G = Go.
+ arctan (< dv/dt) /g), and a correction calculation circuit that corrects errors due to acceleration and deceleration of the vehicle and outputs the corrected tilt angle (G).

According to the above structure, the object of the present invention can be completely achieved.

First, the basic principle of the present invention will be explained. FIG. 1 is a diagram for explaining the basic principle of a correction device for a tilt angle sensor according to the present invention.

The force Fa that a weight of mass m receives during acceleration/deceleration is F a =
m (dv/dt)...-(1). Here, an angle α such that Fa becomes equal to F when force Fa is applied during acceleration and deceleration is included in the measured value of the inclination angle as an error (3). This F is F=mg tanα-121. Since Fa = F, by equations (1) and (2), m (dv/dt) = mg tanα,', t
anα= (dv/dt)/g,・,α−ar
ctan ((dv/dt)/g) -+3).

Assuming that the measured value of the tilt angle sensor is Go, the true 11J
The i oblique angle G is (, -Go-arctan ((dv /dt) /
gl −+41. Here, G is positive when it is inclined upward in the direction of travel of the vehicle.

Next, the present invention will be explained in more detail based on examples.

FIG. 2 is a block diagram showing an embodiment of the tilt angle sensor correction device according to the present invention.

The tilt angle sensor correction device according to the present invention includes a vehicle speed sensor 1
, a tilt angle sensor +2, an AD converter 3, a microcomputer 4, a driver 5, and a display device (4) 6.

FIG. 3 is a diagram for explaining a vehicle speed sensor used in the embodiment of the present invention. The vehicle speed sensor 1 is a sensor for detecting the actual vehicle speed of the vehicle, and its output is connected to the microcomputer 4.

The vehicle speed sensor 1 has a shaft 11 that rotates at the same time as the axle;
A thin iron plate 12 provided with a large number of light passing windows 12a.
, a light emitting element 13 provided on one side of the iron plate 12, and a light receiving element 14 provided on the other side of the iron plate 12 and receiving light emitted by the light emitting element 13 through a light passing window 12a.

The speed of the light receiving element 14 is determined from the time difference between when it first receives light and when it receives the next light. That is, the distance traveled by the shaft 11 during one rotation is l, and the number of light passing windows 12a is N.
, where the time interval of receiving light is t, the vehicle speed V is determined by v-N/(I!, t).

FIG. 4 is a diagram for explaining the tilt angle sensor (5) used in the embodiment of the present invention. The tilt angle sensor 2 is a sensor that detects and outputs the tilt of the vehicle from the relative angle between the weight and the vehicle body, and its output is sent to the AD converter 3.
It is connected to the microcomputer 4 via.

The tilt angle sensor 2 consists of a weight 21 and a variable resistor 22, as shown in FIG. This is a sensor that detects corners.

. FIG. 5 is a flowchart for explaining the operation of the microcomputer used in the embodiment of the present invention.

The microcomputer 4 inputs the vehicle speed v detected by the vehicle speed sensor 1 and the tilt angle Go detected by the tilt angle sensor 2 (41).

Calculate the difference Δv=vn-vn-1 between the vehicle speed vn input in step 41 and the previously stored vehicle speed vn-1, divide it by the loop time t, and calculate the acceleration dv/dt (42
). Note that loop time refers to the time required to go around Pro (6) Durham.

From the dv/dt determined in step 42 and the known gravitational acceleration g, the equation (3), that is, α-arctan ((
Calculate the tilt angle error α from dV/dt)/g) (4
3).

From the inclination angle Go input in step 41 and the error α calculated in step 43, the true inclination angle G is determined by the G-
Calculate from Go-α44) and output the result G (
45).

The output of the microcomputer 4 is displayed on a display device 6 via a driver 5.

As described in detail above, according to the present invention, it is possible to correct the error in the tilt angle during acceleration and deceleration, so that the correct tilt angle of the vehicle can be displayed.

Note that if the navigation system uses the tilt angle corrected by the tilt angle sensor correction device according to the present invention, errors can be reduced even when driving in mountainous areas.

[Brief explanation of the drawing]

(7) FIG. 1 is a diagram for explaining the basic principle of the tilt angle sensor correction device according to the present invention, FIG. 2 is a block diagram showing an embodiment of the tilt angle sensor compensation device according to the present invention, and FIG. The figures are for explaining the vehicle speed sensor used in the embodiment device of the present invention, FIG. 4 is a diagram for explaining the tilt angle sensor used in the embodiment device of the present invention, and FIG. is a flowchart for explaining the operation of the microcomputer used in the embodiment device of the present invention. 1...Vehicle speed sensor 2...Inclination angle sensor 3...A
D converter 4...Microcomputer 5...Driver 6...Display device Patent applicant Suzuki Motor Co., Ltd. agent Patent attorney Hisashi Inoro (8) -8! 5th figure -90-

Claims (1)

[Scope of Claims] A tilt angle sensor correction device that corrects a tilt angle detection error due to acceleration/deceleration of a tilt angle sensor that detects and outputs a relative angle with the vehicle body using a weight suspended from the vehicle body. a vehicle speed sensor that detects and outputs the actual vehicle speed, an output (CO) of the tilt angle sensor, and an output (v) of the vehicle speed sensor.
) is connected to a correction calculation circuit which performs error correction due to acceleration and deceleration of the vehicle from the following formula and outputs the corrected inclination angle (G). . Note G=GO+arctan ((dv/dt)/g)
However, g: gravitational acceleration or less