how to design a smart car model

HOW TO DESIGN ASMART CAR MODELFrom Requirements to Implementation

Speaker: Fei Cheng

Latex XJTLU Template

http://www.treee.com.cn/doku.php?id=os:treee

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Design FlowRequirements

Functions & Features

Components Selection

Analysis

Using Background Knowledge

Circuit Design, Simulation

and Verification

Pass

Fail

PCB Schematic and

Layout

Debug and Test

Using Tech and Skills

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Requirements

• A smart car model with sensors

• Multiple applications

• Powered by battery

• For beginners

• Soldering practice

• Programming practice

• Not expensive

• ……

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Functions and Features

MCU

Car

ModelSensors

Hardware

Beginner

Price

Applications

Battery

Soldering

Programming

Conditions

Size

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Functions and Features

• MCU Functions?

Difficulty?

• Car model: Steering mechanism?

Motor?

Motor Driver?

• Sensors Types?

How to obtain data from sensors?

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Components Selection

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MCU

• ARM Cortex M Family (32 bits)

• Digital Signal Processer (DSP, 32 bits)

• Simple MCU (16 bits, 8 bits)

Beginner Price

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MCU

• ARM Cortex M Family (32 bits)

• Digital Signal Processer (DSP, 32 bits)

• Simple MCU (16 bits, 8 bits)

Beginner Price

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Simple MCU

• TI MSP 430

• STM 8

• Atmel AVR

• Arduino

Beginner Applications

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Simple MCU

• TI MSP 430

• STM 8

• Atmel AVR

• Arduino

Beginner Applications

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Arduino

• Arduino Uno

• Arduino Nano

Size

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MCU

• Arduino Nano

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Car Model

• PCB used as the chassis (底盘)

• Special chassis

Beginner Price Size

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Car Model

• PCB used as the chassis (底盘)

• Special chassis

Beginner Price Size

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Motor

• DC brush motor

• DC brushless motor

Beginner Applications

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Motor

• DC brush motor

• DC brushless motor

Beginner Applications

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Motor

Size

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Motor Driver

• IC based driver

• Transistor of Power MOSFET based driver

Beginner Price

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Motor Driver

• IC based driver

• Transistor of Power MOSFET based driver

Beginner Price

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Motor Driver

• L293

Size Price

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Sensors

• Applications: Auto driving following black line

Collision avoidance and falling prevention

• Black line tracking Optics method

Camera based method

• Falling prevention Optics method

• For collision avoidance Mechanical method

Optics method

Beginner

Price

Multiple

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Sensors

• Applications: Auto driving following black line

Collision avoidance and falling prevention

• Black line tracking Optics method

Camera based method

• Falling prevention Optics method

• For collision avoidance Mechanical method

Optics method

Beginner

Price

Multiple

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Sensors

• IR sensors ITR20001

• Collision Switches

Beginner

Price

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Sensor Data

• All the sensor signals are digital switch signals

• Problem: there are 14 switch signals, but Arduino Nano only has 11 digital input pins.

• Parallel in serial out shift register 2 x 74XX165

Only 4 Pins

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Block Diagram

Arduino Nano

AAA BATx4

+5 Power IC

L293

Motor 1

Motor 2

Speed

PWM

Interruption input

74XX165SPI

IR sensor 1 IR sensor 2 IR sensor 6…

Switch 1 Switch 2 Switch 6…

Key 1

Key 2

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Circuit Design

• Follow the knowledge from your modules EEE103

EEE104

EEE109

• Follow the datasheet of ICs How to connect?

Examples

Electrical characteristics

……

• Follow your experience

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How to become an engineer?

INCEPTION

• Initially motivation – interested in EEE

• Basic knowledge – 103,104,109,116,203,204…

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How to become an engineer?

• Do not try to remember all the knowledge and information

• Just remember the index of them: Key words

Webpages

Our own database

• Search: IC companies’ website

IC datasheets

Shops (Taobao, Digikey ……)

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IC Companies

• TI: MSP430, DSP, Analog IC, Low power, expensive

• ST: STM8/32, cheap

• Atmel: AVR, fast

• Freescale: Automobile Electronic

• Linear: Analog, Power

• Infineon: Power IC, MOSFET

• Altera: FPGA

• Nordic: Wireless IC

• ……

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IC Companies

• TI

• ST

• Atmel

• Freescale

• Linear

• Infineon

• Altera

• Nordic

• ……

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IC Companies

• TI

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IC Companies’ Website

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IC Companies’ Website

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IC Companies’ Website

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Brainstorming

An idea

Search

TI

STM8

L293

74HC165

MSP430

STM32

IRF530

ST

DC-DC DC-AC

7805Arduino

DSP

24L01

Bluetooth

ESP8266

74HC595

C

C++

Java

TCP/IP

3D Print

IR Sensor

Switch

IRF9530

……

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Brainstorming

An idea

Search

L293

74HC165

DC-DC

7805Arduino

Bluetooth

C

C++

IR Sensor

Switch

……

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Brainstorming

idea

TI

STM8

L293

74HC165

MSP430

STM32

IRF530

ST

DC-DC DC-AC

7805Arduino

DSP

24L01

Bluetooth

ESP8266

74HC595

C

C++

Java

TCP/IP

3D Print

IR Sensor

Switch

IRF9530

……

idea

idea

idea

ideaidea

idea

idea

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Brainstorming

Your Knowledge 39

Simulation and Verification

• Simulation Software Multisim

Pspice

Proteus

• Breadboard Verification Try each part

Find problems

Redesign

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PCB Schematic

• Software: Altium designer

Cadsoft Eagle PCB

KiCad

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PCB Layout

• Footprint Inline elements

Surface mount

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Test and Debug

• Write codes to test each function

• Debug codes

• Find problems of circuit

• Improve circuit and PCB board

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Thanks

• Email: c@treee.com.cn

TREEE Wechat My Wechat

www.treee.com.cn www.feieee.com

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