OBJECTIVES To design and implement a Car Black Box

System for the four wheelers record the main driving data of the car comprehensively and accurately in real-time

To reconstruct the accident with data process software, which can help people analyze the accident rapidly and legitimately after a collision

Car Travelling Data Recorder based on Embedded System

Functional Block Schematic

LCD DISPLAY

POWER SUPPLY

Embedded controlATMEL89S52

MAX 232System Interface

EEPROM24C04

RTCDS1307

ADC MCP3208

MEMSACCELEROMETE

R

SIGNAL CONDITIONING

AMPLIFIER

DOOR LOCK

DETECTOR

SEAT BELT POSITION

DETECTOR

CAMERA

(mobile)

CURRENT DRIVER

MEMS ACCELEROMETER –ADXL335

FEATURES 3-axis sensing Small, low profile package

4 mm × 4 mm × 1.45 mm LFCSP Low power : 350 μA (typical) Single-supply operation: 1.8 V to 3.6 V 10,000 g shock survival Excellent temperature stability BW adjustment with a single capacitor per axis RoHS/WEEE lead-free compliant APPLICATIONS Cost sensitive, low power, motion- and tilt-sensing applications

Mobile devices Gaming systems Disk drive protection Image stabilization Sports and health devices

MEMS ACCELEROMETER –ADXL335

RELAY DRIVER-ULN 2003

LCD’s are used as numerical indicators, especially in digital watches where their much smaller current needs than LED displays prolong battery life.

The LCD display used in this project consists of 2 rows. Each row consists of maximum 16 characters.

we cannot read back the LCD’s internal Busy Flag which tells us if the LCD has accepted and finished processing the last instruction.

This problem is overcome by inserting known delays into our program.

LCD DISPLAY

LCD CIRCUIT DESCRIPTION

MAX 232 –APPLICATION CIRCUIT

SEAT BELT POSITION SWITCHING

SEAT BELT SWITCHING

REAL TIME CLOCK-DS 1307

REAL TIME CLOCK-DS 1307FEATURES Real-Time Clock (RTC) Counts Seconds, Minutes, Hours, Date of the Month, Month, Day of the week, and Year with Leap-Year Compensation Valid Up to 2100 56-Byte, Battery-Backed, General-Purpose RAM with Unlimited Writes I2C Serial Interface Programmable Square-Wave Output Signal Automatic Power-Fail Detect and Switch Circuitry Consumes Less than 500nA in Battery-Backup Mode with Oscillator Running Optional Industrial Temperature Range:

-40°C to +85°C Available in 8-Pin Plastic DIP or SO Underwriters Laboratories (UL) Recognized

EEPROM MEMORY-24C04

ADC – MCP3208

Features• 12-bit resolution• ± 1 LSB max DNL• ± 1 LSB max INL (MCP3204/3208-B)• ± 2 LSB max INL (MCP3204/3208-C)• 4 (MCP3204) or 8 (MCP3208) input channels• Analog inputs programmable as single-ended orpseudo-differential pairs• On-chip sample and hold• SPI serial interface (modes 0,0 and 1,1)• Single supply operation: 2.7V - 5.5V• 100 ksps max. sampling rate at VDD = 5V• 50 ksps max. sampling rate at VDD = 2.7V• Low power CMOS technology:- 500 nA typical standby current, 2 μA max.- 400 μA max. active current at 5V• Industrial temp range: -40°C to +85°C• Available in PDIP, SOIC and TSSOP packages

ADC – MCP3208

Features

• Compatible with MCS-51™ Products

• 8K Bytes of In-System Reprogrammable Flash Memory

• Endurance: 1,000 Write/Erase Cycles

• Fully Static Operation: 0 Hz to 24 MHz

• Three-level Program Memory Lock

• 256 x 8-bit Internal RAM

• 32 Programmable I/O Lines

• Three 16-bit Timer/Counters

• Eight Interrupt Sources

• Programmable Serial Channel

EMBEDDED CONTROL ATMEL 89C52

INTERNAL ARCHITECTURE

POWER SUPPLY

Advantages & Applications

The functions of Car Black Box are as follows:

Car Black Box can monitor and record real-time statusof the car (including driving speed, rev, light, car door,tire pressure, brake, lay-up and life belt, etc);

Car Black Box can analyze the accident and handlemany problems related to car accident like crashlitigation, insurance settlements.

When a car accident happens, Car Black Box canprovide diagnosis of the car and help maintenancepersonnel judge faults of the car.

Car Black Box has an alarm which can alarmautomatically when the car is over speed.

REFERENCES

[1] R. Conatsera, J. Wagnerb,*, S. Gantab, I. Walkerb“Diagnosis of automotive electronic throttle control systems” Departments

ofMechanical and Electrical Engineering, Clemson University, Automotive Research Laboratory, 212 Fluor Daniel Engineering Building. [2] Matsushita Electric Industrial Co., Ltd.(Panasonic), SanDiskCorporation, and Toshiba Corporation. SD Specications Part 1 PhysicalLayer Simplied Specication Version2.00. SD Card Association, September 2006. [3] Comprehensive study of digital signal Proeessing devieesDeka RabinMieroproeessors and Mierosystems. [4] Feynman Software Technology Co. Ltd July, MiniGUI Programming Guide Beijing, 2006. [5] William F. Powers*, Paul R. Nicastri“Automotive vehicle control challenges in the 21st century”Ford Research Laboratory, Ford Motor Figure 4 Flow chart of read function Company, 2101 Village Road,

Dearborn, MI 48121-2053, USA.

Functional block schematic

Driving SpeedTire pressureLife beltDoor lockCollision Detector

Data processing

Embedded control

Data Storage MAX 232

Data processing

Bird view Camera

Flash Memory