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1. A
Seminar
on
Embedded Systems
in
Robotics
(An initiative of Electronics Hobby Club)
by
Akash Deep Singh
B.E 7th Semester (Power Electronics & Instrumentation)
Jorhat Institute of Science & Technology

2. “A system is an arrangement in
which all its units assemble and
work together according to the
plan or program.”

3. It is a time display SYSTEM
Parts: Hardware, Needles, Battery, Dial,
Chassis and Strap
Rules
1.All needles move clockwise only
2.A thin needle rotates every second
3.A long needle rotates every minute
4.A short needle rotates every hour
5.All needles return to the original position after 12 hours

4. It is an automatic clothes washing SYSTEM
Parts: Status display panel, Switches & Dials,
Motor, Power supply & control unit, Inner
water level sensor and solenoid valve.
Rules
1.Wash by spinning
2.Rinse
3.Drying
4.Wash over by blinking
5.Each step display the process stage
6.In case interruption, execute only the remaining

5. It is a computing based system.
Or
“A computer inside a product”
Parts: Input Unit, Microcontroller(or
Microprocessors), Application
Software, Additional Mechanical Parts,
Output Unit
Rule:
1. Runs on the specified application
software
2.Has specific requirements and
perform predefined task.

6. An Embedded System is one that has
computer hardware with software embedded
in it as one of its important components.
SOFTWARE PROGRAM
#include <16f876a.h>
#use delay (clock=20000000)
#byte PORTB=6
main()
{
set_tris_b(0);
portb=255;
//decimal
delay_ms(1000);
portb=0x55;
//hexadecimal
delay_ms(1000);
portb=0b10101010; //binary
delay_ms(500);
}

7. And many more………….

8. Why do we require such systems???
Real-time operation
size
cost
time
reliability
safety
energy
security

9. CENTRE OF STUDY???

10. PRODUCT : ROBOT
1. Sensors: In order to sense the environment
2. Actuators : For movement of robots and its parts
3. Control: Controller/Processor as a brain of the robot
4. Intelligence: User written command to perform desired set
of action
5. Power: A necessity for making a system work
6. Communication: Robot can talk to another robot/PC

11. In human analogy: “SENSE ORGANS”

What is a sensor?
In common parlance,
“Anything that can sense a change”
In electronics,
A sensor is a device that measures a physical quantity and
converts it into a signal which can be read by an observer or by an
instrument.

12. 1. IR Sensors
IR sensor works on the principle of
2. Position encoders emitting IR rays and receiving the
reflected ray by a receiver (Photo
3. Ultrasonic Sensors
Diode).
4. Accelerometers
IR source (LED) is used in forward
5. Gyroscope
bias.
IR
6. Infrared TSOP Receiver Receiver (Photodiode) is used in
reverse bias.
7. Motion Sensor
8. GPS

13. In human analogy: “Response”
Actuators are the final control elements (F.C.E) used in all kinds
of control systems.
D.C Motor
D.C Geared Motor
Servo Motor
Stepper Motor

14. The actual manifestation of an embedded system…

15. Microcontrollers manufacturers:
INTEL
8031,8032,8051,8052,8751,8752
PIC
AVR Architecture
8-bit PIC16, PIC18,
16-bit DSPIC33 / PIC24,
PIC16C7x
 Architecture developed by Brogen & Wollan
 American based industry est.. In the year 1984
 AVR stands for Alf & Vegard’s RISC processor
Motorola
 Later developed by ATMEL in the year 1996
 MC68HC11
Focus on embedded systems build around
microcontrollers
Atmel  ATMEL stands for “Advanced Technology for Memory &
Logic
AtMEGA 8,16,32,64,128,256 etc
AT90S2333

17. PROGRAMMING THE MICROCONTROLLER FOR SPECIFIED TASK
1. What is AVR Atmega 8 microcontroller
1. What are ports?
2. Basic idea of C programming
Junctions where peripherals
are Use of embedded C to create a small
3. connected.
This program can be
peripherals
a. Input units
b. Output units
4. Run the program on the bot.
2. Ports in Atmega8
 Atmega8 is a 28 pin micro.
 23 pins can be used as both
input and output pins.
 PINS are grouped together
as PORTS

18.  Atmega8
has Two 8-bit Input/Output Ports
PORTx;
‘x’ is subscript and could be either
of B,D
 Atmega8 has One 6-bit Input/Output port
PORTC
 All ports can be configured individually as input/ouput
 How to access the port?
Each port has three registers associated with it
1. DDRx
2. PORTx
3. PINx

19. DDRx Register
1. DDR stands for “Data Direction Register”
2. Purpose: To set PORT Pins as input or output
DDRx=0; // PORTx is defined as INPUT
DDRx=1; // PORTx is defined as OUTPUT
Example: Let us make PORTB upper nibble as output and lower nibble as input
Hex conversion of first nibble: F
Hex conversion of second nibble: 0

20. PINx Register:
 The purpose of this register is to read the value from the input device connected to the
PORT.
Or
To read data present on PORTx
Example: Read data from PortC (PLEASE NOTE: PORTC HAS BEEN DEFINED AS INPUT PORT)
PINC=0xF0;
Or we can also create a variable
such that
x=PINC
x=0xF0

21. PORTx Register
 This register works in two different ways depending on the way in which the port is defined
Case1: When portx is defined Output
The purpose will be to output data present on the Portx pin to the output device
Example: Here we define PortB as output by assigning
DDRB=0xFF
Let the data present on the PortB be 0xFF
Therefore we write
Case2: When portx is defined as input , it is used to activate or deactivate
the pull-up resistor

24. AVR Programming Tools
 Software Required
ATMEL STUDIO 6
1. Integrated Development Environment (IDE)
2. Supports Developing and Debugging of AVR and ARM based
microcontroller application
WE WILL WRITE THE C PROGRAM AND COMPILE IT IN ATMEL
STUDIO TO GENERATE HEX FILE (MACHINE LANGUAGE
UNDERSTANDABLE BY THE MICROCONTROLLER)
Hardware Required
HEX FILE CAN BE LOADED INTO THE MICROCONTROLLER USING
BOOTLOADER or AVR PROGRAMMERS