My Journey Through MTech in Automotive Electronics

?? Excited to share that I've completed my MTech in Automotive Electronics from BITS! ????

This post might be a bit late, but it's never too late to celebrate.

During my studies, I delved into a variety of subjects and gained hands-on experience with several key concepts and technologies:

Some of them are below!!!

Electrical & Electronics:

• Diodes: Explored threshold voltage, reverse breakdown voltage, and types like Zener diodes. Learned about charge carrier transport through the depletion layer at the p-n junction.

// Threshold Voltage V_th = ...;

// V_th is the minimum voltage required to turn on a diode

// Reverse Breakdown Voltage V_BR = ...;

// V_BR is the voltage at which a diode conducts in reverse

• Thyristors: Studied current control via gate electrodes, including DIACs, TRIACs, and GTOs.

// Thyristor Equation I = I_0 (exp(V / (n V_T)) - 1);

I is the current,

I_0 is the reverse saturation current,

V is the voltage, n is the ideality factor,

V_T is the thermal voltage

• Transistors: Covered BJT, IGBT, FET, and MOSFET, and their use as amplifiers.

// Transistors

// BJT Current Gain beta = I_C / I_B;

beta is the current gain, I_C is the collector current,

I_B is the base current

// MOSFET Drain Current I_D = k * pow((V_GS - V_th), 2);

I_D is the drain current,

k is the process transconductance parameter,

V_GS is the gate-source voltage,

V_th is the threshold voltage

DC-DC Converters:

• Analyzed buck, boost, and buck-boost converters, focusing on the relationship between duty cycle, input, and output voltages.

// DC-DC Converters

// Buck Converter V_out = D V_in;

V_out is the output voltage,

D is the duty cycle,

V_in is the input voltage

// Boost Converter V_out = V_in / (1 - D);

V_out is the output voltage,

V_in is the input voltage,

D is the duty cycle

// Buck-Boost Converter double V_out = D V_in / (1 - D);

V_out is the output voltage,

D is the duty cycle,

V_in is the input voltage

Battery Management Systems:

• Investigated SoH and SoC states, active and passive balancing, and flyback converters.

// State of Charge (SoC) SoC = (Q_current / Q_max) * 100;

SoC is the state of charge,

Q_current is the current charge,

Q_max is the maximum charge

Magnetic Circuits:

• Examined the relationship between flux density, permeability, coil turns, current, voltage, and field strength.

// Magnetic Circuits

// Magnetic Flux Phi = B A;

Phi is the magnetic flux,

B is the magnetic flux density,

A is the area

// Magnetomotive Force (MMF) MMF = N I;

MMF is the magnetomotive force,

N is the number of turns, I is the current.

Induction Motors:

• Learned formulas for slip, torque, power, impedance, and stator current for both 3-phase and 1-phase motors.

// Induction Motors

// Slip s = (N_s - N_r) / N_s;

s is the slip,

N_s is the synchronous speed,

N_r is the rotor speed

// Torque T = P_out / omega_s;

T is the torque,

P_out is the output power,

omega_s is the synchronous speed

Diagnostics & Prognostics:

• Focused on predicting system/component failures and health management (PHM).
• OBD

Testing & Measurement:

• Utilized oscilloscopes, multimeters, and error calculation techniques.

Sensors:

• Studied sensor deviations like sensitivity, non-linearity, hysteresis, noise, sampling frequency, range, and resolution.

Inverter Phase Diagrams:

• Analyzed 120° and 180° phase diagrams.

120° Phase Diagram: Ensures balanced power delivery and reduces harmonic distortion. 180° Phase Diagram: Provides smoother power output and better efficiency in power conversion.

Automotive Security:

• Conducted TARA (ISO/SAE 21434), studied security attacks (DoS, snooping), and mechanisms (ciphertext, rail fence).
• Explored functional safety (ISO 26262), cybersecurity (ISO 21434), and privacy (ISO 27001).

CAN Protocols:

• Standard CAN Frame and CAN FD, including error detection techniques and attacks (spoofing, tampering, DoS).

Standard CAN Frame:

Start of Frame (SOF)

Identifier (ID)

Remote Transmission Request (RTR)

Control Field

Data Field (0-8 bytes)

CRC Field (Cyclic Redundancy Check)

ACK Field (Acknowledgement)

End of Frame (EOF)

Sample CAN Message:

SOF = 0;

ID = 0x123;

RTR = 0;

Control_Field = 0x08;

Data_Field[8] = {0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88};

CRC_Field = 0x1D;

ACK_Field = 0;

EOF = 1;

Communication Protocols:

• LIN, MOST, FlexRay, and their vulnerabilities.

RADAR & LIDAR:

• Studied range equations, limiting factors, Doppler effect, and FoV.

Radar Range Equation R = pow((P_t G_t A_r sigma) / (pow(4 M_PI, 2) * P_r), 0.25);

R is the range,

P_t is the transmitter power,

G_t is the gain of the transmitting antenna,

A_r is the effective aperture, sigma is the radar cross section,

P_r is the received power

Image Processing:

• Applied mask and convolution techniques, including Canny edge detection.

// Image Processing Techniques

Edge Detection: Identifies the boundaries within images.

Gaussian Blur: Reduces image noise and detail.

Histogram Equalization: Enhances the contrast of images.

Thresholding: Converts grayscale images to binary images.

Embedded Systems:

• Programmed microcontrollers, LED displays, and Arduino, focusing on communication channels.

Simple LED Program:

Simple LED Program

// Define the LED pin int ledPin = 13;

void setup()

{

// Initialize the LED pin as an output

pinMode(ledPin, OUTPUT);

}

void loop()

{

// Turn the LED on

digitalWrite(ledPin, HIGH);

delay(1000); // Wait for 1 second // Turn the LED off

digitalWrite(ledPin, LOW);

delay(1000); // Wait for 1 second

}

Software Proficiency:

• Hands-on experience with Proteus, Dorleco, Amesim, Matlab, Simulink, and Altair EmbedADAS, ANSYS Maxwell.

Automotive control systems

• controllers and its derivation portions

Proportional (P) Controller

u(t) = Kp e(t)

Kp - Proportional gain

e(t) - Error signal (difference between the desired setpoint and the actual process variable)

Proportional-Integral (PI) Controller

u(t) = Kp e(t) + Ki ∫e(t) dt

Kp - Proportional gain

Ki - Integral gain

e(t) - Error signal

∫e(t) dt - Integral of the error signal over time

Proportional-Integral-Derivative (PID) Controller

u(t) = Kp e(t) + Ki ∫e(t) dt + Kd de(t)/dt

Kp - Proportional gain

Ki - Integral gain

Kd - Derivative gain

e(t) - Error signal

∫e(t) dt - Integral of the error signal over time

de(t)/dt - Derivative of the error signal with respect to time

OP amplifiers circuit and formula

?? Achieving ASIL Levels A to D in Automotive Safety! ??

• ASIL A: The lowest level of risk, requiring basic safety measures.
• ASIL B: Moderate risk, necessitating more stringent safety protocols.
• ASIL C: High risk, demanding rigorous safety requirements and testing.
• ASIL D: The highest level of risk, involving the most stringent safety measures and thorough validation processes.

?? Exploring the Versatility of PIC16F877A Microcontroller! ??

• Basic Programming: Configuring GPIO pins, utilizing timers and interrupts, performing ADC for analog signals, and implementing communication protocols like UART, SPI, and I2C.

Using Datasheet for entire microcontroller configuration.

RLC Circuit

An RLC circuit consists of a Resistor (R), Inductor (L), and Capacitor (C). It can be connected in series or parallel.

Series RLC Circuit:

- Impedance (Z): The total opposition to the flow of current.

Z = sqrt (R**2 + (X_L - X_C) **2)

R: Resistance (ohms, Ω),

X_L: Inductive reactance,

X_C: Capacitive reactance

- Resonant Frequency (f_0): The frequency at which the circuit resonates.

f_0 = 1 / (2 pi sqrt (L * C))

L: Inductance (Henries, H),

C: Capacitance (farads, F)

- Quality Factor (Q): A measure of the sharpness of the resonance.

Q = 1 / R * sqrt (L / C)

R: Resistance (ohms, Ω),

L: Inductance (Henries, H),

C: Capacitance (farads, F)

Parallel RLC Circuit:

- Admittance (Y): The total measure of how easily a circuit allows current to flow.

Y = sqrt (G**2 + (B_L - B_C) **2)

G: Conductance (siemens, S),

B_L: Susceptance of the inductor,

B_C: Susceptance of the capacitor

- Resonant Frequency (f_0):

f_0 = 1 / (2 pi sqrt (L * C))

L: Inductance (Henries, H),

C: Capacitance (farads, F)

- Quality Factor (Q):

Q = R * sqrt (C / L)

R: Resistance (ohms, Ω),

C: Capacitance (farads, F),

L: Inductance (Henries, H)

RC Circuit

An RC circuit consists of a Resistor (R) and a Capacitor (C). It can also be connected in series or parallel.

- Series RC Circuit:

- Time Constant (τ): The time required for the voltage to rise to 63.2% of its final value.

tau = R * C

R: Resistance (ohms, Ω),

C: Capacitance (farads, F)

- Voltage across Capacitor (V_C): The voltage across the capacitor as it charges.

V_C = V_0 (1 - exp (-t / (R C)))

V_0: Initial voltage (volts, V)

t: Time (seconds, s),

R: Resistance (ohms, Ω),

C: Capacitance (farads, F)

- Parallel RC Circuit:

- Time Constant (τ):

tau = R * C

# R: Resistance (ohms, Ω),

C: Capacitance (farads, F)

- Voltage across Capacitor (V_C):

V_C = V_0 exp (-t / (R C))

# V_0: Initial voltage (volts, V),

t: Time (seconds, s),

R: Resistance (ohms, Ω),

C: Capacitance (farads, F)

LC Circuit

An LC circuit consists of an Inductor (L) and a Capacitor (C). It can be connected in series or parallel.

- Series LC Circuit:

- Impedance (Z):

Z = complex (0, X_L - X_C)

X_L: Inductive reactance,

X_C: Capacitive reactance

- Resonant Frequency (f_0):

f_0 = 1 / (2 pi sqrt (L * C))

# L: Inductance (Henries, H),

C: Capacitance (farads, F)

- Parallel LC Circuit:

- Admittance (Y):

Y = complex (0, B_L - B_C)

B_L: Susceptance of the inductor,

B_C: Susceptance of the capacitor

- Resonant Frequency (f_0):

f_0 = 1 / (2 pi sqrt (L * C))

L: Inductance (Henries, H),

C: Capacitance (farads, F)

Different Types of Motors and Their Basic Calculations

1. DC Motors

DC motors convert direct current electrical energy into mechanical energy. They are commonly used in applications requiring variable speed and torque.

Types:

Brushed DC Motor

Brushless DC Motor (BLDC)

Permanent Magnet DC Motor (PMDC)

Series Wound DC Motor

Shunt Wound DC Motor

Compound Wound DC Motor

Basic Calculation:Torque T = (P 60) / (2 pi N)

P: Power (watts),

N: Speed (RPM)

Armature Current I_a = V / R_a

V: Voltage (volts),

R_a: Armature resistance (ohms)

2. AC Motors

AC motors convert alternating current electrical energy into mechanical energy. They are widely used in industrial and household applications.

Types:

Synchronous Motor

Asynchronous (Induction) Motor

Squirrel Cage Induction Motor

Slip Ring Induction Motor

Basic Calculation:

Power P = V* I PF sqrt (3)

V: Voltage (volts),

I: Current (amperes),

PF: Power factor

Torque (T): T = (P*60) / (2 pi N)

P: Power (watts),

N: Speed (RPM)

Convolution and correlation are fundamental operations in image processing, often used for tasks such as filtering, edge detection, and template matching. Despite their similarities, they serve different purposes and have distinct mathematical definitions.

Convolution

Convolution is a mathematical operation used to combine two functions to produce a third function. In image processing, it involves flipping a filter (kernel) and sliding it over the image to produce a new image.

Correlation

Correlation measures the similarity between two signals or images. In image processing, it involves sliding a filter over the image without flipping it.

Kirchhoff's Laws

Kirchhoff's Current Law (KCL)

Kirchhoff's Current Law states that the total current entering a junction (or node) in an electrical circuit is equal to the total current leaving the junction. This is based on the principle of conservation of electric charge.

Formula:

sum(I_in) = sum(I_out)

I_in: Currents entering the node,

I_out: Currents leaving the node

Kirchhoff's Voltage Law (KVL)

Kirchhoff's Voltage Law states that the sum of all the voltages around any closed loop in a circuit is equal to zero. This is based on the principle of conservation of energy.

Formula:

sum(V) = 0

V: Voltage drops around the loop

Voltage Divider Law

The Voltage Divider Law is used to calculate the voltage across a particular resistor in a series circuit. It states that the voltage is divided among the resistors in proportion to their resistance.

Formula:

V_out = V_in * (R2 / (R1 + R2))

V_in: Input voltage,

R1: Resistance of the first resistor,

R2: Resistance of the second resistor

Doppler Effect

The Doppler effect, also known as the Doppler shift, is the change in frequency or wavelength of a wave in relation to an observer who is moving relative to the wave source. This phenomenon is commonly observed with sound waves, but it also applies to electromagnetic waves such as light.

The observed frequency (f') can be calculated using the following formula:

f'= f * ((v + v_0) / (v + v_s))

Where:

f: Emitted frequency of the source

v: Speed of waves in the medium (e.g., speed of sound in air)

v_0: Velocity of the observer relative to the medium (positive if moving towards the source)

v_s: Velocity of the source relative to the medium (positive if moving away from the observer)

RTOS Task Scheduling and Prioritization

Real-Time Operating Systems (RTOS) are designed to handle multiple tasks efficiently, ensuring that critical tasks are executed within their deadlines. Here are some key concepts and methods used for task scheduling and prioritization in RTOS:

1. Fixed-Priority Scheduling (FPS)

In Fixed-Priority Scheduling, each task is assigned a static priority level. The RTOS scheduler always selects the highest-priority task that is ready to execute.

2. Preemptive Scheduling

Preemptive scheduling allows higher-priority tasks to interrupt lower-priority tasks, ensuring that critical tasks are executed promptly.

3. Round-Robin Scheduling

Round-robin scheduling assigns equal time slices to tasks of the same priority, cycling through them in a circular order.

4. Time Slicing

Time slicing divides the CPU time into slices and allocates them to tasks, ensuring that each task gets a fair share of the CPU.

5. Dynamic Priority Adjustment

Dynamic priority adjustment allows the system to change task priorities during runtime based on specific conditions or requirements.

Schmitt Trigger

A Schmitt trigger is a comparator circuit with hysteresis, implemented by applying positive feedback to the non-inverting input of a comparator or differential amplifier. It converts an analog input signal to a digital output signal, effectively removing noise from the input signal.

How It Works

The Schmitt trigger uses two distinct threshold voltages: an upper threshold (V_UT) and a lower threshold (V_LT). The output switches from low to high when the input exceeds the upper threshold and switches back from high to low when the input drops below the lower threshold. This dual-threshold action is known as hysteresis.

Basic Formulas

Upper Threshold Voltage (V_UT):

V_UT = V_ref * (R1 / (R1 + R2))

V_ref: Reference voltage,

R1 and R2: Resistors in the voltage divider

Lower Threshold Voltage (V_LT):

V_LT = V_ref * (R3 / (R3 + R4))

V_ref: Reference voltage,

R3 and R4: Resistors in the voltage divider

Applications

Noise Filtering: Removes noise from signals in digital circuits.

Waveform Shaping: Converts noisy analog signals into clean digital signals.

Oscillators: Used in relaxation oscillators for generating square waves.

Switch Debouncing: Eliminates noise from mechanical switches.

???? Exploring the World of Hybrid Vehicles and its architecture????

Hybrid vehicles are transforming the automotive landscape with their innovative technology and environmental benefits. Here’s a quick overview of the different types of hybrid vehicles:

1. Mild Hybrids (MHEV): These vehicles use a small electric motor to assist the gasoline engine, especially during acceleration and to power accessories. They can't run on electric power alone.
2. Full Hybrids (HEV): Capable of operating on electric power, gasoline power, or a combination of both, full hybrids often use regenerative braking to recharge their batteries. The Toyota Prius is a well-known example.
3. Plug-In Hybrids (PHEV): With larger batteries that can be recharged by plugging into an external power source, these hybrids can travel longer distances on electric power alone compared to full hybrids.
4. Range-Extended Electric Vehicles (REEV): Primarily running on electric power, these vehicles have a small gasoline engine that acts as a generator to recharge the battery when it gets low.

On-Board Diagnostics (OBD) codes, also known as Diagnostic Trouble Codes (DTCs), are essential for identifying and troubleshooting vehicle issues. Here’s a brief overview:

1. What are OBD Codes?

- Generated by your vehicle's computer, OBD codes help pinpoint specific problems within the engine, transmission, and emissions systems.

2. Types of OBD Codes:

- Generic Codes (P0xxx): Standard across all vehicle makes and models.

- Manufacturer-Specific Codes (P1xxx): Unique to each vehicle manufacturer.

3. Common OBD Codes:

- P0420: Catalyst System Efficiency Below Threshold – Often indicates a catalytic converter issue.

- P0300: Random/Multiple Cylinder Misfire Detected – Usually caused by faulty spark plugs or ignition coils.

- P0171: System Too Lean – Indicates an imbalance in the fuel-to-air ratio.

- P0442: Evaporative Emission Control System Leak Detected (Small Leak) – Typically points to a leak in the emission control system.

4. How to Read OBD Codes:

- Use an OBD-II scanner to read the codes from your vehicle’s computer. Once you have the code, you can look it up to understand the issue and find potential solutions.

???? Project: Optimizing Solenoid Valves for New Working Conditions ????

The project focused on the optimization of solenoid valves to adapt to new working circumstances. This involved using ANSOFT Maxwell for detailed analysis and simulations. The project was successfully completed, showcasing the potential for improved performance and reliability in automotive applications.