Electronic Systems Design for Driver Alertness

Abstract

Automotive systems are getting more responsive and giving feedback to the driver and passengers with the help of electronic systems ensuring safety. As seen the growth towards electric mobility engineers are more indulged in electronic systems and presenting innovative ideas for future developments. The presented simulation model of an electronic system combines the engine coolant temperature sensor, oxygen sensor, and seat belt warning system. The system is proposed using TINKERCAD software and the software is designed through Arduino. The driver will be able to see the temperature of the coolant and also can find out whether the air and the fuel mixture is rich or lean as well as be alerted for wearing a seatbelt.

Introduction

I. INTRODUCTION

Automobiles are getting very responsive and give quick feedback to the commands of passengers. This growth is possible because of the electronic systems present inside the car body. Electronic systems can diagnose any faults and alarm the passengers before any tragedy happens. These systems consist of input, process, and output. They transform one signal to another to give the desired output. These systems can be interconnected to create an electronic system. This assessment describes some types of sensors used in automobiles which after interfacing with the microcontroller creates a reliable electronic system, also the working of different sensors combined to interface with the same microcontroller is presented.  The following circuit diagram of an automotive electronic system interfaces an engine coolant temperature sensor, an oxygen sensor, and a seat belt warning system with a microcontroller and gives the information to the driver.  The aim of creating this system is to inform the driver about coolant temperature and show whether the air and fuel mixture is rich or lean to ensure a smooth performance of the vehicle. The driver should get notified about wearing the seatbelt before driving.

II. DESIGN

The temperature sensor, air to fuel ratio sensor and pushbutton sends input to the microcontroller and microcontroller provides output to the buzzer, LED and LCD. In the circuit design, the temperature sensor senses the engine coolant temperature and it is then displayed on the LCD.  The gas sensor represents the air to fuel ratio sensor and the data is displayed on the LCD as rich mixture or lean mixture or stoichiometric mixture.

The pushbutton works like a seatbelt buckle, when pressed, the buzzer and LED stops.

III. SOFTWARE DESIGN

IV. FUNCTIONAL BLOCK DIAGRAM

V. LIST OF SENSORS AND ACTUATORS REQUIRED

1. Arduino Uno which is based on ATmega328p microcontroller
2. Temperature sensor (TMP36)
3. Gas sensor representing air to fuel ratio sensor
4. LED
5. Buzzer
6. LCD 16*2
7. Pushbutton representing locking of seatbelt

A. Controller Description

A microcontroller is a small computer with CPUs as cores along with memory[1]. In this project, the ATmega328p microcontroller is used to interface with sensors.

Figure 2: Microcontroller (ATmega328)

ATmega328 is an AVR microcontroller manufactured by Microchip. It follows RISC Architecture and processes up to 8 bits of data. It has a flash type program memory which can store data up to 32KB.

VI. ANALYSIS OF SENSORS

1. The Temperature Sensor (TMP36): Used here indicates the temperature of the engine coolant. It can operate on low voltage from 2.7v to 5v. with an output range of 1v to 2v, it can measure temperature from -40°C to 150°C.[2]

2. Lambda sensor (LSU 4.9): Is used to determine the air to fuel ratio. It has a 6 pin configuration. The power needed to operate it is 7.5v and can run with maximum exhaust temperature of 930°C.[3]

3. Pushbutton: The power rating for pushbutton is MAX 50mA 24V DC, with insulation resistance of 100Mohm at 100v and contact resistance MAX 100mOhm. It can operate under temperature range -20 to +70 ?.[4]

VII. INTERFACING CIRCUIT DIAGRAM

A. For the temperature sensor: The power pin, output pin (signal pin) and ground pin is connected to the 5v pin, A2 pin and ground pin of the Arduino.  

B. For the gas sensor: The A1, H1 and A2 pins are connected to the 5v pin of the Arduino and H2 pin is connected to ground pin of the Arduino. B2 pin is connected to the ground via a 20kohm resistor. B1(signal pin) pin is connected to the A1 pin of Arduino.

C. For the pushbutton: The terminal 1a is connected to the ground pin of the Arduino via a 10kohm resistor. Terminal 2a is connected to the 5v pin of Arduino. Terminal 1b(signal pin) is connected to the digital pin2 of Arduino.

D. The LED is connected with the Arduino digital pin4 via a 120ohm resistor and the buzzer is connected to the digital pin5 of Arduino.

E. Data pins DB4, DB5, DB6 and DB7 of the LCD are connected to the digital pins 10, 11, 12, and 13 of the Arduino.

F. The input values from the sensors is displayed on the LCD in a sequence at a time interval of 1 second

VIII. FUNCTIONING OF SYSTEM

When the system is switched on the first warning of wearing a seatbelt is showcased. Unless the driver wears a seatbelt the buzzer and the LED stay on as shown in figure 8. The wearing of seatbelt action is replicated by pushing the button of pushbutton.

The temperature sensor shows the next value of temperature of engine coolant. With the help of the variable button of the temperature sensor we can replicate if the engine coolant temperature is increasing or decreasing as shown in figure 13. The value is the displayed accordingly.

Conclusion

The system works efficiently with minute lag which can be due to data processing. A combined system like the one presented, will be an advantage for a vehicle and for the passengers as well. The driver can have an eye on the vehicle\'s performance just by getting display information and also as a matter of safety the system can alert the driver to wear the seat belt. Further changes can be done in the system for more safety and alerts.

References

[1] “What is a Microcontroller? Programming, Definition, Types & Examples,” The Engineering Projects, Mar. 06, 2018. https://www.theengineeringprojects.com/2018/03/introduction-to-microcontrollers.html (accessed Dec. 23, 2021). [2] “Infineon Developer Community.” https://community.infineon.com/ (accessed Dec. 23, 2021). [3] “Data Sheet_69034379_Lambda_Sensor_LSU_4.9.pdf.” Accessed: Dec. 23, 2021. [Online]. Available: https://www.bosch-motorsport.com/content/downloads/Raceparts/Resources/pdf/Data%20Sheet_69034379_Lambda_Sensor_LSU_4.9.pdf [4] “Push Button Switch,” Components101. https://components101.com/switches/push-button (accessed Dec. 23, 2021).

Copyright

Copyright © 2022 Manas Metar, Rohit Jadhav. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.