CN105946700B - A kind of vehicle brake lamp auxiliary control experimental provision and method - Google Patents

Abstract

The invention discloses a kind of auxiliary of vehicle brake lamp control experimental provision and methods, including vehicle running state detection unit, control unit and Brake lamp display unit；Vehicle running state detection unit is connected with control unit；Control unit includes controller, ON-OFF control circuit, multi-resonant oscillating circuit, ternary counter circuit, decoding circuit；Brake lamp display unit includes display driver circuit；ON-OFF control circuit is controlled by ECU, and ON-OFF control circuit, ternary counter circuit are connected with the display and driving circuit, and multi-resonant oscillating circuit provides clock pulses for ternary counter circuit；Control unit is switched on-off according to vehicle running state, control, and the working condition of output the control decoding circuit and display driver circuit of ternary counter circuit realizes that the light on and off of Brake lamp control by display driver circuit.The present invention detects vehicle difference transport condition, realizes flickering for Brake lamp by the control circuit of design, early warning is carried out to vehicle thereafter.

Description

An experimental device and method for auxiliary control of vehicle brake lights

technical field

The invention belongs to the technical field of vehicle control, and in particular relates to a vehicle brake lamp auxiliary control device and method.

Background technique

In modern society, automobiles have become an indispensable means of transportation. From the previous fuel vehicles to the current electric vehicles, they are not only a means of transportation, but also a symbol of social living standards and the development of social production. However, while cars bring us convenience, they also bring a lot of traffic accidents. The more common traffic accidents are generally collisions at corners or rear-end collisions caused by the sudden braking of the vehicle in front and the failure of the vehicle behind to pay attention in time. Therefore, as a warning light, the brake light of a car is particularly important to reduce rear-end collisions by using the brake light or giving the brake light a more complete function.

Contents of the invention

The present invention fully analyzes several driving states of the vehicle, and whether the brake light is turned on in this state. The premise of the present invention is that the current vehicle has a vehicle behind it and is in a safe driving distance. When the vehicle travels at a constant speed for a period of time, the accelerator pedal is suddenly released, but the brake pedal is not stepped on. At this time, the vehicle will still have a short distance. Acceleration of time, the brake light is not turned on at this time, when the vehicle speed drops after a period of time, and drops to a set threshold of the previous speed, the brake light is on at this time; when the vehicle speed is in the deceleration state, step on the accelerator pedal At this time, the vehicle will still decelerate for a short period of time. When the vehicle speed drops to the set threshold value of the previous speed, the brake light will be on. When the accelerator pedal continues to act and the speed rises, the brake light will go out at this time; The brake pedal, the vehicle speed may still rise for a short period of time, the brake light is not turned on during this period, and when the brake pedal is continuously applied and the vehicle speed drops to the set threshold of the previous speed, the brake light is on. The last one is that the vehicle is stopped, the engine is turned off, and the vehicle brake light is not on.

Based on the above-mentioned analysis, the present invention proposes a vehicle brake light auxiliary control experimental device and method, that is, the vehicle speed is changed due to sudden situations during high-speed driving, and the current vehicle brake light is controlled by turning on and off to give Subsequent vehicles play an early warning role. The invention fully analyzes the current vehicle speed change due to road conditions or other sudden accidents, assuming that there is a vehicle behind it, the current vehicle speed change may cause various driving modes of traffic accidents, and then assists the vehicle to drive by controlling the brake light Avoid tailgating.

The present invention utilizes a vehicle speed sensor, a brake pedal sensor and an accelerator pedal sensor to detect changes in vehicle speed during the running of these types of vehicles, and input the speed changes generated by these types of driving modes into the control unit as an input signal. The design of the control unit control circuit is used to control the brake lights of the vehicle and to play an early warning role for the vehicles behind. The technical scheme adopted is as follows:

An auxiliary control experimental device for vehicle brake lights, comprising a vehicle running state detection unit, a control unit and a brake light display unit; the vehicle running state detection unit includes a brake pedal sensor, an accelerator pedal sensor and a vehicle speed sensor, the The vehicle driving state detection unit is connected to the control unit;

The control unit includes a controller, a switch control circuit, a multivibrator circuit, a ternary counter circuit, and a decoding circuit; the brake light display unit includes a display and a drive circuit; the switch control circuit is controlled by the controller to realize switch on and off, the switch control circuit and the ternary counter circuit are connected to the decoding circuit, the decoding circuit is connected to the display and drive circuit, and the multivibrator circuit is a ternary The control counter circuit provides clock pulse information;

The control unit controls the on-off state of the switch according to the information of the vehicle driving state detection unit, the output information of the ternary counter circuit controls the working state of the decoding circuit and the display and drive circuit, and the display and drive circuit realizes analog braking. Light on and off control.

Further, the switch control circuit includes a switch, an XOR gate, a two-input NAND gate, a three-input NAND gate, and a NOT gate.

Further, the multivibrator circuit is realized by a 555 timer and several resistors and capacitors.

Further, the ternary counter circuit includes two cascaded JK flip-flops.

Further, the decoding circuit includes 3-8 decoders and 6 NAND gates in series; the display and driving circuit includes 6 NOT gates and 6 light-emitting diodes in series; the 6 A light-emitting diode is connected to the power supply through a pull-up resistor, and the light-emitting diode is used to simulate a brake light.

Further, the controller is implemented by a vehicle-mounted ECU or a single-chip microcomputer.

According to the auxiliary control experimental device of the above-mentioned vehicle brake lights, the present invention proposes a control method, including the following situations:

a There is a vehicle speed S at a certain moment;

b Neither the accelerator pedal nor the brake pedal is stepped on, and the vehicle speed increases compared with the previous moment. At this time, it is determined that the vehicle is in the acceleration process, and the vehicle speed is greater than the previous vehicle speed S;

c. Both the accelerator pedal and the brake pedal are not depressed, and the vehicle speed decreases compared with the previous moment. At this time, it is determined that the vehicle is in the deceleration process, and the vehicle speed is lower than the vehicle speed S at the previous moment;

d The accelerator pedal is stepped on, the brake pedal is not stepped on, and the vehicle speed increases compared with the previous moment. At this time, it is determined that the vehicle is in the acceleration process, and the vehicle speed is greater than the previous vehicle speed S;

e The accelerator pedal is depressed, the brake pedal is not depressed, and the vehicle speed decreases compared with the previous moment. At this time, it is determined that the vehicle is in the deceleration process, and the vehicle speed is lower than the previous vehicle speed S;

f The accelerator pedal is not depressed, the brake pedal is depressed, and the vehicle speed increases compared with the previous moment, at this time, it is determined that the vehicle is in the process of speed control;

g The accelerator pedal is not depressed, the brake pedal is depressed, and the vehicle speed decreases compared with the previous moment. At this time, it is determined that the vehicle is in the deceleration process, and the vehicle speed is lower than the previous vehicle speed S;

In the above three deceleration situations of c, e, and g, the vehicle turns on the brake lights when the vehicle speed drops to m% at this moment; in the case of f, the brake lights are also turned on during the speed control process to warn the rear vehicles; In the three acceleration situations of a, b, and d, turn off the brake lights.

Further, the control method of turning on or off the brake lights is as follows: the controller sets the on-off state of the control switch according to the information of the vehicle driving state detection unit, and controls the on and off of the six light-emitting diodes to realize braking Light on and off control; details are as follows:

(1) If neither the brake pedal nor the accelerator pedal is depressed, and the vehicle speed does not change, it means that the vehicle is in normal operation, the control switch is set to 00, and all LEDs are off;

(2) If neither the accelerator pedal nor the brake pedal is stepped on, the control switch is set to 01, and then the light-emitting diodes D4-D5-D6 are controlled to light up or go out according to the vehicle speed state;

(3) If the accelerator pedal is depressed and the brake pedal is not depressed, the control switch is set to 10, and then the light-emitting diodes D1-D2-D3 are controlled to light up or go out according to the vehicle speed status;

(4) If the accelerator pedal is not depressed and the brake pedal is depressed, the control switch is set to 11 state, and then control the light emitting diodes D1-D2-D3-D4-D5-D6 to light up or extinguish according to the vehicle speed state.

Beneficial effects of the present invention:

The innovation of the present invention is reflected in two aspects: firstly, the innovation on the control idea, the traditional vehicle brake light mainly adopts the control mode of machinery or pure circuit, completely depends on the hardware that the brake light system adopts to ensure it The normal operation of the circuit, once the circuit is aging or the contact problem caused by mechanical vibration and the deformation of the mechanical component can not trigger the circuit power switch in time, which will cause the circuit to malfunction. Such problems often occur. Therefore, there is almost no other reliable method to avoid such failures except for selecting better hardware system components. Therefore, it is very necessary to select intelligent components for system design and increase system stability and operability. and significant. Secondly, the innovation in the control idea, through the detection of the speed change of the vehicle under different driving conditions, the brake light is turned on and off through the controller control circuit, so as to give early warning to the vehicles behind.

Description of drawings

Fig. 1 is a schematic diagram of the present invention;

Fig. 2 is a schematic diagram of the state analysis of the present invention to control the turning on and off of the brake lights;

Fig. 3 is the control circuit diagram of control unit of the present invention;

Fig. 4 is the circuit diagram of the control switch circuit submodule of the present invention;

Fig. 5 is a sub-module diagram of a decoding circuit, a display and a driving circuit;

Fig. 6 is a ternary counter circuit submodule diagram;

Fig. 7 is a sub-module diagram of the multivibrator circuit.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

In the normal driving state of the vehicle, the speed of the vehicle needs to be changed during the driving process. The speed of the vehicle is detected through the speed detection unit. By judging the driving state of the vehicle, the control unit makes adjustments to the on and off state of the brake lights of the car to give it Carry out a certain early warning of the vehicles behind, thereby reducing or even avoiding the occurrence of rear-end collision accidents.

As shown in Figure 1, the structure of the present invention includes a vehicle driving state detection unit, a control unit MCU, and a vehicle brake light display unit. The vehicle driving state detection unit uses a vehicle speed sensor, a brake pedal sensor and an accelerator pedal sensor. Through the detection of the vehicle driving state, the control unit adjusts the on and off state of the brake lights of the vehicle to give certain warnings to the vehicles behind.

As shown in Figure 2, in different driving states, the vehicle speed sensor detects the vehicle speed at each moment, and determines the change of the vehicle speed at the current moment and the vehicle speed at the previous moment, and controls the switch of the brake light according to the judgment result. Specifically divided into the following situations:

a There is a vehicle speed S at a certain moment.

b Neither the accelerator pedal nor the brake pedal is depressed, and the vehicle speed increases compared with the previous moment. At this time, it is determined that the vehicle is in the acceleration process, and the vehicle speed is greater than the previous vehicle speed S.

c. Both the accelerator pedal and the brake pedal are not depressed, and the vehicle speed decreases compared with the previous moment. At this time, it is determined that the vehicle is in the deceleration process, and the vehicle speed is lower than the vehicle speed S at the previous moment.

d The accelerator pedal is stepped on, the brake pedal is not stepped on, and the vehicle speed increases compared with the previous moment. At this time, it is determined that the vehicle is in the acceleration process, and the vehicle speed is greater than the previous vehicle speed S.

e The accelerator pedal is depressed, the brake pedal is not depressed, and the vehicle speed decreases compared with the previous moment. At this time, it is determined that the vehicle is in the deceleration process, and the vehicle speed is lower than the vehicle speed S at the previous moment.

f The accelerator pedal is not depressed, the brake pedal is depressed, and the vehicle speed increases compared with the previous moment. At this time, it is determined that the vehicle is in the process of speed control.

g The accelerator pedal is not depressed, the brake pedal is depressed, and the vehicle speed decreases compared with the previous moment. At this time, it is determined that the vehicle is in the deceleration process, and the vehicle speed is lower than the vehicle speed S at the previous moment.

In the three deceleration situations of c, e, and g, the brake light of the vehicle whose speed drops to m% during this period should be turned on; in the case of f, the brake light should also be turned on during the speed control process to warn the rear vehicles; and In a, b, d three acceleration situations, the brake light is off. In the embodiment of the present invention, m=15.

As shown in Figure 3 to Figure 7, it is the internal control circuit included in the vehicle internal control unit. It is mainly composed of switch control circuit, ternary counter, decoding circuit, display and driving circuit and 555 clock pulse circuit. The switch control circuit is composed of a switch, an XOR gate, a two-input NAND gate and a three-input NAND gate; the ternary counter is designed to be composed of two cascaded JK flip-flops, and the decoding circuit uses a 3-wire-8 The line decoder 74LS138 and 6 NAND gates are composed, and the display and driving circuit is composed of 6 light-emitting diodes (D1, D2, D3, D4, D5, D6) and 6 inverters connected in series. The 555 clock pulse multivibrator circuit is composed of a 555 timer and resistors and capacitors.

When the change range of the vehicle speed reaches the set threshold m%, triggered by the clock pulse generated by the 555 multivibrator, the ternary counter controls the decoder circuit, and outputs low level sequentially, so that the display and drive circuit control The brake lights are turned on as required, so as to realize the process of turning on and off the brake lights of the vehicle.

The working mode of the control unit of the present invention is as follows:

① The vehicle starts at a low speed V0 at the initial stage, and the brake pedal is not depressed, when the vehicle speed continues to increase and the duration reaches the set threshold T;

② Or at the initial stage of the vehicle's non-low speed V0 start, the brake pedal is not stepped on, and the vehicle speed becomes larger than the speed at the previous moment, and the change range reaches the set threshold m%;

③ Either the vehicle stops and the handbrake is pulled up; or the ignition switch of the vehicle is turned to the OFF position, and the vehicle is turned off.

In these three driving states, the control unit switches off the brake lights.

④ Depress the brake pedal;

⑤Compared with the previous moment, the vehicle speed decreases, and the decrease reaches the set threshold m%. At this time, no matter whether the accelerator pedal or the brake pedal is stepped on, the brake lights are turned on to warn the vehicles behind.

In both cases, the control unit controls the brake lights to come on.

The control of the brake light above is realized through two controllable switches S0 and S1, and the combination of switches S0 and S1 can produce four states of 00, 01, 10 and 11. details as follows:

(1) If neither the brake pedal nor the accelerator pedal is depressed, and the vehicle speed does not change, it means that the vehicle is in normal operation, the control switch is set to 00, and all LEDs are off;

(2) If neither the accelerator pedal nor the brake pedal is stepped on, the control switch is set to 01, and then the light-emitting diodes D4-D5-D6 are controlled to light up or go out according to the vehicle speed state;

(3) If the accelerator pedal is depressed and the brake pedal is not depressed, the control switch is set to 10, and then the light-emitting diodes D1-D2-D3 are controlled to light up or go out according to the vehicle speed status;

(4) If the accelerator pedal is not depressed and the brake pedal is depressed, the control switch is set to 11 state, and then control the light emitting diodes D1-D2-D3-D4-D5-D6 to light up or extinguish according to the vehicle speed state.

For example, the control switch S1 is closed and S0 is disconnected, that is, S1S0=10, and the output of the XOR gate connected to the switch is a high level "1", which makes the enable terminal E3 of the 3-8 decoder effective at this time, and the 3-8 The decoder works normally; the address terminal C of the decoder is connected to the switch S0, because S0 is disconnected, so the S0 terminal is "0", and the ternary counter is triggered by the output pulse of the multivibrator to realize 00- The ternary cycle of 01-10, that is, the input signals of the BA ports of the decoder are 00-01-10 in turn, combined with the input signal "0" at the C terminal at this time, the decoding address input terminal CBA signals of the decoder are respectively It is 000-001-010, after being decoded by the decoder, the output terminals Y0-Y1-Y2 of the decoder are at low level (the output is valid), and at this time D1-D2-D3 are lit. Because the switch S0 is turned off, the C terminal of the decoder is at low level, so D4-D5-D6 are in the extinguished state. In this way, it can be judged that the vehicle's accelerator pedal is stepped on, and the brake pedal is not stepped on, and the vehicle speed drops to 15% after the brake light is turned on (ie, the control of the driving mode e).

In the same way, the circuit designed when the switches S1S0=00, S1S0=01, and S1S0=11 can also realize the normal running of the car, the accelerator pedal and the brake pedal are not stepped on and the accelerator pedal is not stepped on, and the brake pedal is stepped on Brake light control function in three states.

The series of detailed descriptions listed above are only specific descriptions for feasible implementations of the present invention, and they are not intended to limit the protection scope of the present invention. Any equivalent implementation or implementation that does not depart from the technical spirit of the present invention All changes should be included within the protection scope of the present invention.

Claims (8)

1. a kind of auxiliary control experimental device of vehicle brake light, it is characterized in that, comprise vehicle running state detection unit, control unit and brake light display unit; Described vehicle running state detection unit comprises brake pedal sensor, accelerator pedal sensor and a vehicle speed sensor, the vehicle driving state detection unit is connected to the control unit; The control unit includes a controller, a switch control circuit, a multivibrator circuit, a ternary counter circuit, and a decoding circuit; the brake light display unit includes a display and a drive circuit; the switch control circuit is controlled by the controller to realize switch on and off, the switch control circuit and the ternary counter circuit are connected to the decoding circuit, the decoding circuit is connected to the display and drive circuit, and the multivibrator circuit is a ternary The control counter circuit provides clock pulse information; The control unit controls the on-off state of the switch according to the information of the vehicle driving state detection unit, and the output information of the ternary counter circuit controls the working state of the decoding circuit and the display driving circuit, and the display driving circuit realizes the activation of the analog brake light. On and off control. 2. The auxiliary control experimental device of a kind of vehicle brake light according to claim 1, wherein the switch control circuit comprises a switch, an exclusive OR gate, a two-input NAND gate, a three-input NAND gate and a NAND gate. Door. 3. The auxiliary control experimental device of a kind of vehicle brake light according to claim 1, characterized in that, the multivibrator circuit is realized by a 555 timer and several resistors and capacitors. 4 . The auxiliary control experiment device of a vehicle brake light according to claim 1 , wherein the ternary counter circuit comprises two cascaded JK flip-flops. 5. The auxiliary control experiment device of a kind of vehicle brake light according to claim 1, is characterized in that, described decoding circuit comprises 3-8 decoders, 6 NAND gates connected in series in sequence; The display and driving circuit includes 6 NOT gates and 6 light emitting diodes connected in series; the 6 light emitting diodes are connected to the power supply through a pull-up resistor, and the light emitting diodes are used to simulate brake lights. 6 . The experimental device for auxiliary control of a vehicle brake light according to claim 1 , wherein the controller is implemented by a vehicle-mounted ECU or a single-chip microcomputer. 7 . 7. The control method of the auxiliary control experimental device of a kind of vehicle brake light according to any one of claims 1-6, characterized in that, comprising the following situations: a There is a vehicle speed S at a certain moment; b Neither the accelerator pedal nor the brake pedal is stepped on, and the vehicle speed increases compared with the previous moment. At this time, it is determined that the vehicle is in the acceleration process, and the vehicle speed is greater than the previous vehicle speed S; c. Both the accelerator pedal and the brake pedal are not depressed, and the vehicle speed decreases compared with the previous moment. At this time, it is determined that the vehicle is in the deceleration process, and the vehicle speed is lower than the vehicle speed S at the previous moment; d The accelerator pedal is stepped on, the brake pedal is not stepped on, and the vehicle speed increases compared with the previous moment. At this time, it is determined that the vehicle is in the acceleration process, and the vehicle speed is greater than the previous vehicle speed S; e The accelerator pedal is depressed, the brake pedal is not depressed, and the vehicle speed decreases compared with the previous moment. At this time, it is determined that the vehicle is in the deceleration process, and the vehicle speed is lower than the previous vehicle speed S; f The accelerator pedal is not depressed, the brake pedal is depressed, and the vehicle speed increases compared with the previous moment, at this time, it is determined that the vehicle is in the process of speed control; g The accelerator pedal is not depressed, the brake pedal is depressed, and the vehicle speed decreases compared with the previous moment. At this time, it is determined that the vehicle is in the deceleration process, and the vehicle speed is lower than the previous vehicle speed S; In the above three deceleration situations of c, e, and g, the vehicle turns on the brake lights when the vehicle speed drops to m% at this moment; in the case of f, the brake lights are also turned on during the speed control process to warn the rear vehicles; In the three acceleration situations of a, b, and d, turn off the brake lights. 8. The control method according to claim 7, characterized in that, the control method of turning on or off the brake lights is: the controller sets the on-off state of the control switch according to the information of the vehicle driving state detection unit , to control the on and off of six light-emitting diodes to realize the on and off control of the brake lights; the details are as follows: (1) If neither the brake pedal nor the accelerator pedal is stepped on, and the vehicle speed does not change, it means that the vehicle is in normal operation, the control switch is set to 0 0, and all LEDs are off; (2) If neither the accelerator pedal nor the brake pedal is stepped on, the control switch is set to 0+1 state, and then the light-emitting diodes D4-D5-D6 are controlled to light up or go out according to the vehicle speed state; (3) If the accelerator pedal is depressed and the brake pedal is not depressed, the control switch is set to 1 0 state, and then the light-emitting diodes D1-D2-D3 are controlled to light up or go out according to the vehicle speed state; (4) If the accelerator pedal is not depressed and the brake pedal is depressed, the control switch is set to 11, and then the LEDs D1-D2-D3-D4-D5-D6 are controlled to light up or go out according to the vehicle speed status.