JPH0524460A - Safety device for vehicle - Google Patents

Abstract

PURPOSE:To provide a safety device for vehicle for preventing a a dangerous state during driving a vehicle by controlling vehicle running based on the physiological state of the driver. CONSTITUTION:A safety device for a vehicle 1 consists of a skin electric potential detecting means 2 for detecting skin electric potential of a driver; a deciding means 3 for deciding the state of the driver whether he is excessively strained or his awakening state is decreased based on generation frequency of an SPR which is a sudden change in the skin electric potential and the decreasing rate of the skin electric potential; a fuel injecting control unit 4 for performing speed control of a vehicle when the driver is decided in his excessively strained state or his awakening state is decreased; and a display unit 5 for displaying a message to the driver according to the speed control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle safety device for controlling a vehicle so that it can be operated safely.

[0002]

2. Description of the Related Art Conventionally, in order to perform a safe operation of a vehicle, a steering angle of a steering wheel is detected, and a drowsiness driving is warned by comparing the steering angle change with a predetermined steering angle value corresponding to a vehicle speed. An alarm device (Japanese Utility Model Laid-Open No. 56-73638) or an abnormal operation alarm device (actually Japanese Patent Application Laid-Open No. 58-58) that detects an abnormal operation by detecting the operating state of a vehicle. 2676) and other safety devices have been proposed.

[0003]

However, these safety devices do not directly detect the physiological condition of the vehicle driver and cannot be said to be sufficient in terms of accuracy. Further, even when the steering angle of the steering wheel is detected, it is not enough to understand the decrease in awakening degree (drowsiness) of the vehicle driver, and it is not enough to understand the tension state of the vehicle driver.

The present invention has been made in view of the above circumstances, and an object thereof is to control the operation of a vehicle based on the physiological condition of the vehicle driver so as to prevent a dangerous state during the operation of the vehicle. It is to provide a safety device for a vehicle that can be prevented.

[0005]

In order to achieve the above object, the present invention provides a skin potential detecting means for detecting the skin potential of a vehicle driver and a change rate of the skin potential detected by the skin potential detecting means. Based on the state of abrupt potential change, the rate of change of which is equal to or greater than a set value, a tension state determination means for determining the excessive tension state of the driver, and a skin potential detected by the skin potential detection means. Based on the degree of decrease of
When the driver is determined to be in an excessively tensioned state by the driver's awakened state determination means for determining the driver's reduced arousal state, the tension state determination means performs speed control of the vehicle, When the driver determines that the driver is in a decreased awakening state by the awakened state determination means, the technical means includes a control means for performing speed control to gradually reduce the vehicle speed. To do.

[0006]

The vehicle safety device of the present invention having the above structure is
By detecting the skin potential of the vehicle driver, it is possible to determine whether the vehicle driver is in an excessively tense state or in a state of reduced arousal level. Then, when it is determined that the vehicle driver is in an excessively nervous state or in a state of reduced awakening, the control means controls the speed of the vehicle.

Specifically, when the vehicle driver is in an excessively nervous state, control is performed such that the vehicle speed is limited or the acceleration response is lowered. Further, when the vehicle driver is in a state of low awakening level, control is performed such that the vehicle speed is gradually reduced.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a vehicle safety device of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing an outline of a vehicle safety device.

This vehicle safety device 1 includes a skin potential detecting means 2 for detecting a skin potential (Skin Potential Level) of a driver (vehicle driver) and an excessive tension of the driver based on the detected skin potential of the driver. And a fuel injection control unit 4 (control means) for controlling the speed of the vehicle when it is determined that the driver is in an excessively tense state or in a low awakening state. In accordance with this speed control, the display unit 5 and the like for displaying a message in accordance with the driver's excessive tension or reduced awakening state are constructed.

As shown in FIG. 2, the skin potential detecting means 2 includes a first electrode 6 attached to a finger of a driver and a second electrode 7 attached to a wrist, and the first electrode 6 and the second electrode. It comprises a transmission unit 8 for amplifying and transmitting the weak SPL signal measured by 7.

The judging means 3 includes a receiving unit 9 for wirelessly receiving the SPL signal sent from the transmitting unit 8,
It comprises a microcomputer 10 for performing the following calculations. The microcomputer 10 includes an SPR calculation circuit 10a that calculates SPR (Skin Potential Response) that is a rapid change in skin potential, and an SPL decrease degree calculation circuit 10b that calculates the degree of decrease in skin potential. Also, it is determined whether the driver is in an excessively nervous state or in a low awakening state based on the degree of decrease in SPL.

For the occurrence of SPR, a skin potential change rate V / t (see FIG. 3; a diagram showing a rapid skin potential change) is obtained, and this change rate is equal to or greater than a preset value. To do. In addition, the driver's excessive tension is defined as the number of SPR occurrences within a predetermined time exceeding a preset number of times, and the driver's decreased arousal level is a setting with a degree of SPL decrease. It is assumed that the value falls below the value (see FIG. 4; graph showing changes in skin potential with time).

The fuel injection control unit 4 controls the opening of a throttle valve (not shown) to limit the vehicle speed by the control signal output from the microcomputer 10 when the driver is in an excessively tight state. However, when the driver is in a state of low awakening, the vehicle speed is controlled to be gradually reduced.

The display unit 5, for example, "please relax" (see FIG. 5) in case of excessive tension.
When you are in a state of low alertness, “Please stop driving”
A display plate 5a for displaying a message such as (see FIG. 6),
The speaker 5b plays the message as voice.

Next, the operation of this embodiment will be described based on the flowchart of the microcomputer 10 shown in FIG.
First, initialization is performed (step S1), and the vehicle speed V0 and the opening W of the throttle valve are called in (step S1).
2). Next, it is judged from the SPR occurrence frequency whether the driver is in an excessive tension state (step S3), and if it is judged that the driver is in an excessive tension state (YES),
It is determined whether the opening W of the throttle valve is larger than a preset value X (step S4).

If the opening W of the throttle valve is smaller than the set value X (NO), the process returns to step S2.
When the opening W of the throttle valve is larger than the set value X (YES), the opening of the throttle valve is controlled so that W = X (step S5). As a result, the vehicle speed V0 is limited, and even if the accelerator pedal is depressed, the vehicle speed V0 is prevented from increasing.

Simultaneously with the limitation of the vehicle speed V0, the display unit 5 displays a message "Please relax" and a voice (step S6) to warn the driver of the excessive tension.

If it is determined in step S3 that the driver is not in an excessively tense state (NO), it is determined whether or not the driver's arousal level is lowered (step S7). In this determination, if the driver's arousal level is not lowered (N0), initialization is performed (step S8), and the process returns to step S2. When the driver's arousal level is decreasing (YES), the vehicle speed V0 is controlled to be gradually decreased (step S).
9).

Simultaneously with the decrease of the vehicle speed V0, the display unit 5 plays a message "Please stop driving" and a voice (step S10) to warn the driver that the awakening level is low.

In this way, the vehicle can be operated more safely by controlling the speed of the vehicle when the driver is in an excessively nervous state and when the awakening level is low.

In the present embodiment, the excessive tension of the driver is determined by the SPR occurrence frequency, but it may be determined based on the SPR amplitude or the occurrence time (see FIG. 3).
Further, the driver's awakened state may be determined by detecting a stable state of the skin potential at a low level (see FIG. 4).

An example in which the opening of the throttle valve is limited when the driver is in an excessively tight state has been described.
Control may be performed such that the acceleration responsiveness is lowered as compared with the vehicle responsiveness from a normal throttle sensor. Further, the warning to the driver on the display unit 5 simultaneously with the speed control may be accompanied by displaying a message and playing a music or a sound to relax or awaken.

[0023]

The vehicle safety device according to the present invention can accurately determine an excessive tension state and a reduced awakening state by detecting the skin potential which is the physiological state of the vehicle driver. By controlling the speed of the vehicle in both of these states, it is possible to prevent a dangerous state of the vehicle.

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of a vehicle safety device.

FIG. 2 is a diagram showing a usage state of skin potential detecting means.

FIG. 3 is a diagram showing a rapid change in skin potential.

FIG. 4 is a graph showing changes with time in skin potential.

FIG. 5 is a plan view of a display unit.

FIG. 6 is a plan view of a display unit.

FIG. 7 is a flowchart showing the operation of this embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Vehicle safety device 2 Skin potential detection means 3 Judgment means (tension state judgment means, awakening degree reduction state judgment means) 4 Fuel injection control unit (control means)

Claims (1)

Claims: 1. A) skin potential detecting means for detecting the skin potential of a vehicle driver; and b) the rate of change of the skin potential detected by the skin potential detecting means, and the rate of change. Is a set value or more, based on the state of a sudden potential change, a tension state determination means for determining the excessive tension state of the driver, and c) the degree of decrease in the skin potential detected by the skin potential detection means. Based on the driver's wakefulness lowering state determination means, and d) if the driver is judged to be in excessive tension by the tensional state determining means, A vehicle having speed control and a control means for performing speed control so as to gradually reduce the vehicle speed when the driver determines that the driver is in a decreased awakening state by the awakening lowering state determination means. Safety device.