ANTI CRASH VEHICLE SECURITY SYSTEM

MOHD SYUKOR BIN CHE OMAR

This report is submitted in partial Mfilment of the requirement for the award of

Bachelor of Electronic Engineering (Telecommunication Electronic) With Honours

Faculty of Electronics and Computer Engineering

Universiti Teknikal Malaysia Melaka

MAY 2008

ABSTRAK

Projek ini bertujuan untuk membina dan mereka bentuk sistem

keselamatatl kenderaan anti perlanggaran dengan menggunakan pengesan

elektronik jenis ultrasonik serta aplikasi sistem brek anti kuncian dan sistem

kawalan kelajuan motor atau enjin. Sistem keselarnatan anti perlanggaran

kenderaan ini direka bentuk dan dibina untuk mengelakkan kenderaan daripada

mengalami perlanggaran dari hadapan. Projek ini menggunakan implementasi

melalui Pemprosesan Litar Dalaman, PIC dan perisian UATLAB untuk menguji

signal ultrasonik bagi pengesan elektronik tersebut. Selain itu, projek ini turut

menggunakan perisian Multisim dan Protell 99 untuk mereka bentuk litar

elektronik sistem keselamatan anti perlanggaran kenderaan. Sistem ini dibina

untuk mengesan objek atau kenderaan dari hadapan pada kelajuan yang tinggi

bagi rnengelakkan berlaku perlanggaran dan mengaktitkan sistem brek anti

kuncian selain mampu mengawal kelajuan kenderaan apabila kenderaan berada

pada jarak yang h a n g selamat dengan objek atau kenderaan di hadapan.

Keutamaan projek ini adalah mengujikaji dan memprogram litar pengesan

dengan menggunakan Pemprosesan Litar Dalaman, PIC serta aplikasinya.

ABSTRACT

This project is about the design and builds the anti-crash security

system in the vehicle. The anti-crash system that will design involved the

electronic circuit that we learnt like sensor, relay, control system,

rnicrocontroller, IC, signal transmitter and signal receiver, Peripheral

Interface Circuit (PIC). In this project we should be apply the skill and

knowledge in design electronic circuit for the anti-crash system. We use the

software as we learnt before like Protel99 and Multisim to design the circuit.

The concept in design the anti-crash vehicle system is strategic control of an

accident being vehicles. Actually, in this project we consider the distance

anti-crash sensor and to avoid an accident. The system is design to prevent

the driver and passenger inside the vehicle gets an accident with detect the

object in front of them in the safety distance and speed. We will use the

Peripheral Interface Circuit (PIC) to program this project conclude the

application like Anti Braking System (ABS) and Motor Speed Control. We

also study about the safety distance, vehicle speed, wheel speed and signal

transmitter and signal receiver.

CHAPTER I

INTRODUCTION

1.1 INTRODUCTION

The purpose of this project is to design and develop an anti-crash vehicle

security system. Specification of this project is the system use using the combination of

integrated circuit, sensing technology and computerized technology like Programmable

Integrated Circuit microcontroller (PIC-microcontroller) where the integrated circuit

will program by computer. The sensing technology was advance and significant year

by year especially in security system industry where most physical phenomena can be

detected by sensors, monitored by amplifiers and trigger circuits, and then presented by

meters or personal computers [I].

The Anti-Crash Vehicle Security System is developing by using an ultrasonic

sensor with application of Antilock-Braking System (ABS) and Motor Speed Control.

The concept in design the anti-crash vehicle system is strategic control of an accident

being vehicles. The concept which is formulated enables strategic control of

integrated security systems (ISS) considering from the influence-reaction parameter

point [2].

Actually, in this project we consider the distance of ultrasonic sensor and the

application in the system to avoid an accident. The system was designed to prevent

the driver and passenger inside the vehicle gets an accident by detect the object in

front of vehicle in the safety distance and speed, The system operate by using

ultrasonic sensor which detect the object or vehicle in distance that we set in front

our vehicle where the vehicle in high speed. After that, the system will reduce the

speed of vehicle by using motor speed control and will apply the antilock-braking

system (ABS) to avoid the accident between them. Beside that, the system also

provides the speedometer or tachometer to measure the high speed that will cause the

dangerous accident.

The objective of this project is to develop and design an anti-crash vehicle

security system by using Ultrasonic Sensor with switch off the engine system. The

system will designed by using Programmable Integrated Circuit-microcontroller

(PIC-microcontroller) to control and to provide the feedback to other hardware

devices the security system to other devices.

This project also applies the function of PIC micro-controller as the most

important part for hardware circuit. The PIC micro-controller is programmed to

control input from sensor and tachometer and remote to output as motor speed

control and anti-braking system. It also converts an analog output signal from the

sensors into digital signal.

Besides that, the objective of this project also to understand principle of

ultrasonic sensor those provide wide range sensing in automotive industry. This

project also simulates by m T I S I M and MATLAB where the signal from the

sensor can measure and the application of the project can be observe before we

construct the hardware.

13 PROBLEM STATEMENT

Every year, hundreds case of road accident increase in our country, Malaysia.

Thousands of people .died on Malaysian roads and the number of the people died

because of road accident in increase year by year. The table 1.1 shows us the statistic

of an accident in Malaysia fiom 1994 until 2007. In particular compiled by Royal

Malaysia Police, these statistics show how many accidents occur in Malaysia.

Table 1.1 : Statistic of an Accident in Malaysia from PDRM (1 994-2007)

ear

19Q4 148 801 5 159

14Y5 162 4 9 1 5 712

1996 189 109 6 304

1997 215 632 6 302

1998 211 037 5 740

iq99 223 116 5 794

2000 250 429 6 035

2001 265 175 5 849

?m 27" 711 5 Q O i

2083 298 653 6 286

2004 326 814 6 223

2005 328 268 6 188

2006 341 23; 6 287

Ian-Mar 2017 87 668 1 4 8 2

The number of road accident between vehicles are higher because several

factor like condition of the vehicle which not probably safety, the attitude of the

driver and the driver not proficient in handle the vehicle in panic situation. From this

several factor, I get the idea to develop anti-crash vehicle system [3].

Figure 1.1 : Statistics Road Accidents in Malaysia (2005) Source: Royal Malaysian Police ( P D W

An accident statistic in Malaysia is among higher in the world. One of the

factors is the driver failure to control the vehicle in emergency situation. The

situation that the driver face is:

a) Emergency brake

b) Safety distance between vehicles,

c) High speed driving.

From the situation above, I get the idea to build and design the Anti Crash

Vehicle Security System to prevent an accident between vehicles.

1.4 SCOPE OF THE PROJECT

The scope for this project is divided into two parts which a simulation and

hardware part. Far the first part, I have made the simulation for this project to obtain

the expected result and function of the circuit system. In this part, I will use the

MULTISIM software to design and simulate the circuit and result and MATLAB

software to run the simulation of ABS application and analysis. From the simulation

part, I should be able to study and measure the signal strength af the sensor

component that will using in this project that is Ultrasonic Motion Sensor. Besides

that, I can study the function of the Antilock-Braking System (ABS) and Motor

Speed Control. From the simulation also, I can measure the approximately result that

the circuit want.

For the second part, I have to construct the hardware of anti-crash vehicle

security system prototype which consist the ultrasonic motion sensor, motor speed

controller, tachometer and antilock-braking system (ABS) by using the PROTELL

99 software. The PIC micro~controller will also construct and programmed to

integrate with software part as to make sure that the connection between both parts is

available where the input of the sensor can communicate and program to the output

application. In this project, I should be use PIC 16F88. Then, the hardware is

fabricated using printing circuit board [4].

After all the circuit has been design, selected technique will be done in order

to implement the hardware by combining idea and prototype fiom the earlier work.

The circuit that has been created must be constructing and combining it. For this

implementation, it need to do part by part means when finish one part of this project,

the test and troubleshooting can be down slowly

1.5 RESEARCH METHODOLOGY

To achieve the objectives of this project, there are four step procedure of

methodology to be use, This project consists of two parts; simulation part and

hardware part. Because of that, the methodology for this project has been divided

into two processes before I combine to complete anti-crash vehicle security system,

The following is the discussion on project methodology. The best solution for

this project is based on the figure 1.2 below. The project methodology for this project

wills involve four major phase. For the 1 st phase, Literature Review, I have gathered

the information about the project via Internet, journals, magazines, published work

and reference books and study of the software implementation (Multisim, Mikro C,

PIC-microcontroller).

For the second phase, Matlab & Multisim simulation, I have simulate the

circuit of the system for signal and distance measurement by MultisixdMatlab before

construct the hardware. I also built and simulate the anti-crash system and do the

observation and analysis the circuits,

For the third phase, Hardware development, I am using Proteus and Multisim

sohare to design the circuit and do the fabrications process on the Print Circuit

Board (PCB).

For the fourth phase, Testing Hardware, I have making a result comparison

between the fabricated circuits with the simulation.

I Literature Review I

I Writing t her is

Figure 1.2: Project Methodology in a Flowchart

CHAPTER I1

LITERATURE REVIEW

2.1 BACKGROUND STUDY

An interesting safety-related electronic system having potential for future

automotive application is the anti-collision security system. An on-board low-power

radar system can be used as a sensor for a~ electronic collision avoidance system to

provide warning of a potential with an object lying in the path of the vehicle, As

early as 1976, at least one experimental system was developed that could accurately

detect objects up to distances of about 100 yards [5 ] .

Since 1976, anti-collision security system for vehicle was develop where

radar technology and microwave sensor are combined. However, for sensing the

object or vehicle, the reflecting signal and time take between transmit and receive

signal was determine at the sensor component. The round trip time, t, fkom the

transmitter to object and back to receiver is proportional to the range, R, to the object,

as illustrated in figure 2.1 and expressed in the following equation [5 ] :

Round trip time, t = 3

In this project, the vehicle speed, V can be measure by measuring the Doppler

frequency shift of the pulse signal reflected by the ground [5]. (The Doppler

frequency shift is proportional to the speed of the moving object). This reflection can

be discriminate from the object reflectian because the ground reflection is at low

angle and short, fixed range. Ultrasonic or microwave Doppler speed sensors are

used to measure ground speed and travel distance of the vehicles, However, in latest

automotive industry, ultrasonic sensors more using because the wide range of

frequency that the sensor component can cover, In order to solve these problems and

improve the accuracy, a high-resolution ultrasonic Doppler speed sensor was

developed [5] [6].

Rrnge to Object

Radar Protected Car R - --dsiaBb

Object v

Figure 2.1 : Range of Object for Anti-collision Security System

The reflection from an object will have a pulse shape that is very nearly

identical to that of the transmitted pulse, As noted, the security system can detect this

object reflection and find R to determine the distance fiom the vehicle of the object.

In addition, the relative speed of closure between the car and the object can be

calculated by adding the vehicle speed, V, from the ground reflected pulses and the

speed of the object, S , which can be determined from the change in range of the

object's reflection pulses. A block diagram of an experimental collision security

system is shown in figure 2.1 give me an idea to develop and design the antierash

vehicle security system using ultrasonic sensor, motor speed control and antilock-

braking system[5] [6].

Figure 2.2: Block Diagram of Collision Avoidance Securjty System

'='v"t

Generator

Antenna

In this system, the range, R, to the object and the closing speed, V + S; are

measured. If the traveling at the same speed as the radar equipped car and in the

same direction, S = -V is infinite. That is, a collision would never occur. If the object

is stationary, S = 0 ant the time to collision is [5][6]:

Time to collision, T = R Y

e-- Timimg

Meannememt

Vehicle S p e d

This system gives the vehicle speed, which is applicable for antilock-braking systems.

If the object is another moving car approaching the sensor equipped car head-on, the

closing speed is the sum of the two car speeds. In this case, the time to closure is [5] :

1 t

wandng h i v e

Outpltr

S u w r

CPU

Antelma Scan Control

-

Time to closure, T = R

v+s

This concept of the anti-collision security system helps me in my research to

develop the project of anti-crash vehicle security system. My project exactly to

upgrade the performance of the old technology using wide-range and more accurate

sensing like using ultrasonic sensor in PIC-rnicrocontroller. It will interest to watch

this project develop and become commercially available [5][6].

2.2 ULTRASONIC SENSOR SYSTEM

Ultrasonic sensors provide precise no-touch presencelabsence sensing and

distance sensing or tracking. They are particularly useful where other sensing

technologies have difficulty, such as with clear or shiny target objects, foggy or

particle-laden air, and environments with splashing liquids. Ultrasonic solutions are

often used where larger sensors or longer sensing distances are required [7].

Ultrasonic senson work by exciting an acoustic transducer with voltage

pulses, causing the transducer to vibrate ultrasonically. These oscillations are

directed at a target and, by measuring the time for the echo to return to the transducer,

the target's distance is calculated, Ultrasonic sensors generally provide an accuracy

of 1 mm at distances ranging from 100 mm to 6,000 rnrn (over 19 feet) [7].

Target-to-sensor distance is very important in determining maximum

switching frequency. The sensor sends an ultrasonic beam through the air. It takes a

finite time for the signal to leave the sensor, travel to the target, steke the target, and

return to the s e m r as an echo. The farther a target is from the sensor, the longer it

takes the sound to complete this cycle, and the lower the switching frequency [7].

So, in this project I am using the ultrasonic proximity sensor to replace the

microwave sensor to detect the object or vehicle. The ultrasonic proximity sensor is a

reflective sensor that responds to changes in the amount of emitted energy returned

to a detector after interaction with the target distance, Typical systems consist of two

transducers (one to transmit and one to receive the returned energy). n e transmitter

emits a longitude wave in the ultrasonic region of the acoustical spectrum (typically

20-200 kHz), above the normal limits of human hearing. The receiver response is a

h t i o n of the amplitude of the returned energy, as opposed to elapsed time before

detection of an echo [8].

Ultrasonic proximity sensors are useful over distance out to several feet

detecting most objects, liquid and solid, The advent of low-cost microcontrollers was

applied in this project such device have for most situation been replaced by more

versatile ultrasonic ranging systems that provide a quantitative indicator of distance

to the detected object [8].

Time-of-flight ranging systems measure the round trip time required for a

pulse of emitted energy to travel to a reflecting object, then echo back to a receiver of

ultrasonic sensor. The relevant parameters involved in range calculation, therefore,

are the speed of sound in air (roughly 1 foot per millisecond) for ultrasonic sensor

different with the speed of light (1 foot per nanosecond) for microwave sensor. Using

elementary physics, distance is determined by multiplying the velocity of the energy

wave by time required to travel the round-trip distance:

Round trip distance, d = v t (2.4)

Where:

d=round-trip distance

v=speed of propagation

t=elapsed time

In the automotive industry, BMW now incorporates four piezogrwic

transducers (sealed in a membrane for environmental protection) on both front and

rear bumpers in its Park Distance Control system. The most popular commercially

anti-collision vehicle security system was available ultrasonic ranging systems [8],

The ultrasonic sensor system shown in figure 2.3 and 2.4 includes a separate

ultrasonic transmitter and receiver operating at 23 kHz. The ultrasonic system

components shown can be used in a variety of ways [I].

Figy-e 2.3 : Ultrasonic Transmitter

Figure 2.4: Ultraso@ Receiver

2.3 MOTOR SPEED CONTROL

The mechanical system comprises a brushed DC motor of 24 V, permanent

magnet, torque of 7.0 Nm and nominal speed of 300 rpm, Coupled to the wheel shaft,

a low resolution relative encoder (32 ppr) was used to measure motor speed, which is

part of the control system [9],

Figure 2.5: Control System Block Diagram

The pulses generated by the encoder are acquired by the PTC16FS4, an 8 bits

microcontroller with an 8 bits internal counter, 1K Flash memory and 13 I/O pins.

This microcontroller was used in the single chip configuration with a 4 MHz crystal

external circuit to generate the clock. The encoder pulses count, during a preset

period of time, is proportional to wheel speed. This is the way the encoder is used

most of the times, although in this case as the work speed is as low as 180 rpm and

the number of pulses generated in each turn, 32, is also small, a number of five or

more turns should be necessary for the speed measure, with an acceptable uncertainty.

This would make the performance of the system very slow because any correction

would only be made every five turns, A solution is a fixed number of pulses and the

setting of the time spent by these pulses so that the measured time is inversely

proportional to wheel speed. The software solves the problem of the speed being

inversely proportional to measured values [9].

2.4 ANTILOCK BRAKING SYSTEM

One of the most readily accepted applications of electronics in automobiles

has been the antilock brake system (ABS). ABS is a safety-related feature that assists

the driver in deceleration of the vehicle in poor or marginal braking conditions like

the driver failure to control the vehicle in emergency situation like emergency brake

in high speed driving. In such condition, panic braking by the driver (in non-ABS-

equipped cars) results in reduced braking effectiveness and, typically, loss of

directional control due to the tendency of the wheels to lock [5] .

In ABS-equipped cars, the wheel is prevented from locking by a mechanism

that automatically regulates braking force to an optimum for any given low-friction

condition. The physical configuration for ABS is shown in Figure 2.6.

Replace brake tluldcvmy 4aMH) mtks

Figure 2.6: Antilock Braking System

The car is traveling at a speed U and the wheels are rotating at an angular

speed w where

w = w RPM

3 0

and where RPM is the wheel revolution per minute. When the wheel is rolling (no

applied brakes),

where R is the tire radius.

2.5 VELOCITY, POSITION, AND DISPLACEMENT

The measurement of velocity, position and displacement is essential to many

of the processes taking place during the running of the vehicle: speed control,

number of revolutions per minute of the engine, or displacement of the acceleration

and break pedals, to name some of the most typical applications [lo],

Several different technologies are used in the measurement of velocity,

position, and displacement: Eddy Current, This coil-based transducer uses the effect

of eddy currents to sense the proximity of conductive materials. The transducer and

the target establish a magnetic circuit with a nonlinear relationship between the

distance and the impedance of the transducer coil [lo].

Hall Effect. A Hall sensor is a device that, when subjected to a magnetic filed,

provides an output voltage proportional to the magnetic field strength, These devices

can be used as switches or position transducers [lo].

Variable reluctance. These sensors are electromagnetic devices consisting of

a permanent magnet surrounded by a winding of wire, The sensor is used in

conjunction with a ferrous target wheel that has either teeth or notches. When the

target wheel rotates near the sensor it changes the magnetic flux, creating a voltage

signal in the sensor coil [lo].

Reed switch. This kind of the switch consists of two parts: the reed switch

and the actuator magnet. The reed switch will change state when the actuator magnet

comes into close proximity to it [lo].

Wiegand effect. This technology employs specific magnetic properties of the

specially processed, small-diameter ferromagnetic wire, A uniform voltage pulse is

generated when the magnetic field of this wire is suddenly reversing [lo].

Magnetoresistive. This is based on the change of resistivity of a material due

to a magnetic field, The amplitude of that magnetic field depends on the relative

position between a magnet and the transducer [lo].

Potentiometric. These devices use linear or angular potentiometers whose

resistance varies linearly or angularly with length or rotation angle, They are not

used in velocity measurement [lo].

Optical sensors use light emitters and detectors together with a mask wheel in

order to measure angular rotation €1 01.

There are other sensor technologies used or available for use in automotive

applications, Same of them are restricted to classical cars based on the combustion

engines. Obstacle detection, Fardistance obstacle detection is used for avoiding

collision and for cruise control systems that control both vehicle-to-vehicle spacing

and speed. This kind of sensor is implemented using different technologies. They can

be classified in five main groups [11][12].

Milimeter-wave radar detectors are strong against rain and dirt but expensive

and have to comply with national legislation [13].

Laser or IR detectors are also comparatively inexpensive but vulnerable to

rain and dirt. Passive IR detectors are also comparatively inexpensive but vulnerable

to dirt and bad weather conditions [14].

Ultrasonic detectors have low cost and a simple structure but do not provide

good results in the detection of the medium to long distances. Machine vision

detectors have compact size and the ability to detect and classify specific objects.

The main problem is their vulnerability to rain, dirt, and night-time [I 51.

2.6 PIC MICROCONTROLLER

Microcontroller is an essential electronic device that change the electronics

design topology since its inception few decades ago. Basically, microcontroller is a

computer system that is fabricated in a single integrated chip. A microcontroller chip

consists of a central processing unit (CPU) memory modules, and several input/

output peripherals [16].

The rnicrocontroller is used as a device that can form the basis of an

embedded system for electronics applications. It provides a flexible low-cost solution

to bridge the gap between single-chip computers and the use of large numbers of

discrete logic chips [16].

Depending on various manufacturers, microcontroller is divided into several

categories (&bit, 16-bit, 32-bit). Most commonly used microcontroller is &bit

microcontroller. It is simple, small in size, and capable of doing most things related

with control and inputloutput devices [16].

Figure 2.7: PIC 16F88

The PIC microcontrollers are based on RISC (Reduced Instruction Set

Computer) architecture; therefore use a relatively small number of instructions. Most

PICs used 35 instructions compared to some general-purpose microprocessors that

may several hundred [ 1 61.

The important feature of modern PIC devices is use of electrically erasable

and programmable Flash memory for program storage. These Flash memory devices

are often denoted by use of the letter "F" as part of the device coding (16F88). Flash

devices are much easier to work with for one-off prototyping because erasure and

reprogramming is greatly simplified [16].

RA~IAN~NREF+I ClOUT -[

vss --r-[

Figure 2.8: Block Diagram of PIC 16F88

2.7 COMPONENTS AND DEVICES

In this literature review also, the important thing that should be mentioned

earlier is to identified the components and device required for the overall circuit. The

knowledge about all the components is required to make all the connection of the

circuit more easily and accurate because the different devices have different polarity

and different characteristic.

2.7.1 SEVEN SEGMENT DISPLAY

Seven-segment displays are commonly used in electronics as a method of

displaying decimal numeric feedback on the internal operations of devices. The

display shows the decimal numbers 0-9 and is easily understood.

Figure 2.9: Seven Segment Display

The individual segments making up a 7-segment display are identified by

letters as follows:

Figure 2.10: Layout of 7 segments Display

The segments of a 7-segment display are referred to by the letters A to G, as

shown to the right, where the optional decimal point (an "eighth segment") is used

for the display of non-integer numbers. It is an image sequence of a "LED" display,

which is described technology-wise in the following section. Notice the variation

between uppercase and lowercase letters for A-F; this is done to obtain a unique,

unambiguous shape for each letter.

There are two important types of 7-segment LED display. In a common

cathode display, the cathodes of all the LEDs are joined together and the individual

segments are illuminated by HIGH voltages. In a common anode display, the anodes

of all the LEDs are joined together and the individual segments are illuminated by

connecting to a LOW voltage.

a b c d s f g I Common Anode

b

Common Cathode

Figure 2.1 1 : Common Anode & Common Cathode

I have study how to interface 7-seg display to a microcontroller. So, I create a

lookup table containing the seven segment pattern to display the corresponding hex

digits. eg consider we have to display '1' from the figure we come to know that

turning ON segment B & C will show '1' on the 7-seg display so P2.1 & P2.2 should

be LOGIC 0 whereas rest of the pins should be LOGIC 1. Figure below shows the

lookup table for CA display.

Figure 2.12: Truth Table of 7 Segments

2.7.2 LM7805 VOLTAGE REGULATOR

Most digital logic circuits and processors need a 5 volt power supply. To use

these parts we need to build a regulated 5 volt source. Usually we start with an

unregulated power supply ranging &om 9 volts to 24 volts DC. To make a 5 volt

power supply, we use a LM7805 voltage regulator IC (Integrated Circuit). The IC is

shown below.

Figure 2.13: LM7805

A Voltage Regulator (also called a "regulator") has only three legs and

appears to be a comparatively simple device but it is actually a very complex

integrated circuit. A regulator converts varying input voltage and produces a constant

"regulated" output voltage. Voltage regulators are available in a variety of outputs,

typically - 5 volts, 9 volts and 12 volts.

Figure 2.14: Layout of LM9805

The LM7805 is simple to use. I'm simply connect the positive lead of my

unregulated DC power supply (anything from 9VDC to 24VDC) to the Input pin,

connect the negative lead to the Common pin and then when I turn on the power, we

will get a 5 volt supply from the Output pin.

CHAPTER 111

RESEARCH METHDOLOGY

3.1 PROJECT METHODOLOGY

To achieve the objectives of this project, there are four steps procedure of

methodology. This project consists of two parts; simulation part and hardware part.

Because of that, the methodology for this project has been divided into two processes

before I combine to complete anti-crash vehicle security system.

The following is the discussion on project methodology. The best solution for

this project is based on the figure 3.1 below. The project methodology for this project

wills involve seven major phase. For the fmt phase, literature review, I have

gathered the information about the project via internet, journals, magazines,

published work and reference books and study of the software implementation

(Multisim, Mikro C, PIC-microcontrolla).

For the Second phase, Matlab & Multisim simulation, I have simulate the

circuit of the system for signal and distance measurement by Multisim/Matlab before

construct the hardware. I also built and simulate the anti-crash system and do the

observation and analysis the circuits.