CHAPTER 3 :

PLC & ROBOT PROGRAMMING

By

Aziz Mamat

Aspalila Awang

Mechanical Department

Politeknik Kota Bharu

INTRODUCTION

PLC & ROBOT PROGRAMMING

Number System

Binary Number

Octal Number

Decimal Number

Hexidecimal Number

Binary Coded Decimal (BCD) Number

NUMBER EXAMPLES

Bil Binary

(Asas 2)

Octal

(Asas 8)

Decimal

(Asas 10)

Hexidecimal

(Asas 16)

BCD

0 0 0 0 0 0000

1 1 1 1 1 0001

2 10 2 2 2 0010

3 11 3 3 3 0011

4 100 4 4 4 0100

5 101 5 5 5 0101

6 110 6 6 6 0110

7 111 7 7 7 0111

8 1000 10 8 8 1000

9 1001 11 9 9 1001

10 1010 12 10 A 0001 0000

11 1011 13 11 B 0001 0001

12 1100 14 12 C 0001 0010

13 1101 15 13 D 0001 0011

14 1110 16 14 E 0001 0100

15 1111 17 15 F 0001 0101

16 10000 20 16 10 0001 0110

17 10001 21 17 11 0001 0111

18 10010 22 18 12 0001 1000

19 10011 23 19 13 0001 1001

20 10100 24 20 14 0010 0000

BINARY NUMBER

25 24 23 22 21 20

32 16 8 4 2 1

25 24 23 22 21 20

Example :

110102 = (1 x 24) + (1 x 23) + (0 x 22) + (1 x 21) + (0 x 20)

= 16 + 8 + 0 + 2 + 0

= 2610

Convert Binary number to Decimal number

BINARY NUMBER

Convert Decimal number to Binary number

2610

OCTAL NUMBER

Convert Octal number to Decimal number

85 84 83 82 81 80

85 84 83 82 81 80

32768 4096 512 64 8 1

Example :

110508 =(1 x 84) + (1 x 83) + (0 x 82) + (5 x 81) + (0 x 80)

= 4096 + 512 + 0 + 40 + 0

= 464810

BCD NUMBER (BINARY CODED DECIMAL)

Decimal BCD

D C B A

0 0 0 0 0

1 0 0 0 1

2 0 0 1 0

3 0 0 1 1

4 0 1 0 0

5 0 1 0 1

6 0 1 1 0

7 0 1 1 1

8 1 0 0 0

BCD Base number 8 4 2 1

EXAMPLES OF BCD & DECIMAL CONVERSION

Examples:-

a) Decimal 16010 = BCD Number ?

Decimal 1 6 0

BCD 0001 0110 0000

b) Convert BCD 0100 0101 0000 to decimal number.

BCD 0100 0101 0000

Decimal 4 5 0

HEXADECIMAL NUMBER

165 164 163 162 161 160

No Hexadecimal Decimal BCD Binary

0000 0 0000 0

000A 10 0001 0000 1010

0022 34 0011 0100 100010

002A 672 0110 0111 0010 1010100000

FFFF 65535 0110 0101 0101 0011 0101 1111111111111111

Conversion Hexadecimal Number to Decimal, BCD and Binary Numbers

Hexadecimal Number Base

DIGITAL AND ANALOG SYSTEM

Digital System

Digital signal is a pulse or a series of voltage levels varying discret (separated or not continuous), stepped or increased. Two-speed switching characteristics of the level of 'on-off' or top-down, give the impression all digital signal.

EXAMPLES OF DIGITAL SIGNAL

+V

- V

Time

Voltan

0

+ V

- V

TimeVolt a

n

0

Diagram C1 (a) Square Wave.

Diagram C1 (b) Positive Rectangular Wave

EXAMPLES OF DIGITAL SIGNAL

-

V

+V

TimeVo

lta

ge

0

-

V

Voltage

+ V

Time

0

Diagram C1 (c) Negative Square Wave signal

Diagram C1 (d) Digited analog signal.

Analog System

Analog signal is AC or DC currents that vary smoothly and continuously for a certain time. It does not change significantly or stairs. Electronic circuits that produce these signals are called analog circuit.

ANALOG SIGNAL EXAMPLES

+ V

- V

TimeVoltage

0

- V

+ V

TimeVoltage

0

Diagram C2 (a) Sine Wave

Diagram C2 (b) Positive D.C. Voltage

ANALOG SIGNAL EXAMPLES

Diagram C2 (c) Negative Variable D.C. Voltage

+ V

Time

Voltage 0

-V

Diagram C2 (d) Random A.C. Voltage

+ V

Time

Vo

lta

ge

0

-V

COMPARISON

ANALOG AND DIGITAL SYSTEMNo Digital Signal Analog System

1. Processing data or information by calculating or counting. Processing information or data by measuring and

measuring.

2. The data obtained in the form of discrete data or unit volume. The data obtained are constantly changing and

continuously as signal noise and movement.

3. Discrete data are represented by numbers, letters, alphabet,

symbols, and the reading is constant. As an example of discrete

data is a set of binary digits using the number zero (0) or one (1).

If the graph is drawn in a rectangular wave shape of the graph.

Digital data is in the form of graphs or signal patterns

often change in a row. If the graph is drawn in the form of

sine wave graph.

4. The main circuit is the logic gates. The main circuit is operating amplifier (Op-amp).

5. It has a higher accuracy. It has a lower accuracy.

6. Digital signal is less affected by interference effects. For

example, the effect of noise in the sound recording can be

reduced with digitally re-recorded on compact disc (CD).

Analog signals tend to be influenced by interference

effects.

7. Digital systems require analog signal processing requires analog

to digital converter (ADC).

Digital signal can be converted back to analog signals

using digital to analog converter (DAC).

8.

Suitable for use in business and commerce for handling a

number of efficient and discrete data.

Control processes that depend on physical conditions such

as temperature, pressure, level and flow rate. Very suitable

to be used to analyze the system requires continuous

measurement and control.

Examples of digital systems is the calculator. Examples of devices that use an analog system is a 'Virtual

Reality’ and analog computers used in processing

petroleum.

CONVENSIONAL CONTROL SYSTEM, ELECTRONIC AND LOGIC COMMAND SET

CONVENSIONAL CONTROL SYSTEM - Hardwired

control

ELECTRONIC CONTROL SYSTEM - minicomputer

control

LOGIC COMMAND SET CONTROL SYSTEM -

Micro processing control

COMPARISON OF METHODS OF HARDWIRED, MINICOMPUTERS AND MICRO -

PROCESSING CONTROL TO COST, FLEXIBILITY AND RELIABILITY.

Control Method Cost Flexibility Reliability

Hard Wire high

Large size and its

design is not

economically

Low compared to other

methods.

Requires a mechanical stop

to control the robot

movement

Need more cable to run

Low-depending on the design and

method of making the

Lower reliability because they can not

detect its own damage

No resistance to high temperatures

programmed

Mini Computer Highest because it

involves complex

equipment

Best Higher

Micro-Processing High but lower than the

minicomputers

Good Moderate compared with

minicomputers

INTEREST IN THE SYSTEM AUTOMATED

REPEATABILITY

Improve the quality of a product. - high repeatability will allow the installation of components on the right products and installation errors can be reduced. Quality of products is easily controlled and maintained.

Accuracy is very important for repeatability and large quantity of work. Repeatability would be tiring the operator - will affect the quality of the product. With the characteristics of repeatability, operators do not need to repeat the work and only control the machine can operate automatically.

Increase the productivity rate (units / time) because of the repeatability feature, the robot can work automatically and continuously without precise control.

Perform the critical work such as wire bonding process and die attach process. Technicians only teach the robot to work once and the robot can be taught to repeat the work exactly.

The number of operators can be reduced because an operator can control several machines simultaneously, thereby reducing overhead costs such as wages and management costs.

Reduce waste due to high repeatability will reduce the reject rate. With this raw material costs can be reduced.

QUIZ

State three methods of control in agriculture

automation systems.

List five the importance of repeatability in

automated systems.

BASIC IN ROBOT PROGRAMMING

Teach pendant programming

Direct (ON-Line) programming

Computer programming

On-line programming

Off-line programming

TEACH PENDANT PROGRAMMING

COMPUTER PROGRAMMING

Bil Program

1 Operation HOME position

2 GOTO P2 SPEED 80%

3 GOTO P3

4 GRIPPER OPEN

5 GOTO P4 SPEED 20%

6 GRIPPER CLOSED

7 GOTO P3

8 GOTO P5 SPEED 60%

9 GOTO P6 SPEED 20%

10 GRIPPER OPEN

11 GOTO P5

12 GRIPPER CLOSED

13 GOTO P7

14 GOTO P1 SPEED 80%

15 END

Figure 3c Robot motion path and coordinates

Operation HOME position

(P1) (70,70,70)

P2 (50,46,50) P3 (45,30,50)

P4 (45,30,15)

P5 (40,42,50)

P7 (45,47,60)

P6(40,42,20)

BASIC IN PLC PROGRAMMING

Definition of Programmable Logic Controller (PLC)

According to NEMA (National Electrical Manufacturer Association, U.S.), Programmable Logic Controller (PLC) is defined as a system operating on digital electronics, designed in an industrial environment, using the 'Memory' program for internal storage of instructions specified by the user to operate specific functions such as logic, sequencing, timer, counter 'counter' and arithmetic. It is used to control various types of machine or process through the 'input' and 'output' digital. PLC is easy to be integrated into the industrial control system and easy to use for the desired functions.

PLC COMPONENTSProgramming Device

Input / Output Module

Output DeviceInput Device

Power Supply CPU Memory

PLC DEVICES AND FUNCTION

Device Function

Peranti pengaturcaraan

(Programming device)

Equipment used to enter the PLC program

Modul masukan

(Input module)

Convert the input signal from the input module to signal that can be

processed by the PLC and send to the central control unit.

Modul keluaran

(Output module)

Otherwise perform the duties of the PLC to change the appropriate signal to

'output device' such as driving.

Peranti masukan

(Input device)

Equipment used in the system from outside eg receiving signal at various

types of switches and other sensors, external sensors and sends it to the

input module to translate.

Peranti keluaran

(Output device)

Equipment that receive signals from the 'output module' and then carry out

the instructions made by the programs 'PLC' to the system. It consists of

various types of motors, solenoids, lamps, heaters and so on.

Unit pemperosesan pusat

Central Processing Unit

(CPU)

Equipment that receive signals from the 'output module' and then carry out

the instructions made by the programs 'PLC' to the system. It consists of

various types of motors, solenoids, lamps, heaters and so on.

PLC CONTROL UNIT COMPONENTS

Arithmetic logic unit (ALU) - perform arithmetic and logical operations with data

delivered.

Accumulator (AC) – special register is assigned directly to the ALU. It stores data

to be processed and the results of an operation.

Register (Pendaftar) - store instructions called a program memory until it dies in

decoded and implemented (Executed)

Command ( arahan ) – have the operation and the address. the operational

determine the logical operation which will be implemented. part

address defines the operation (input signal, flag etc.) in

which logic operations are performed.

Program counter – register containing the address of the next instruction

be processed.

Control Unit – determining and controlling the entire sequence of logic operations

required to run the command

PLC PROGRAMMING LANGUAGES

• IL - Instructions command in the form mnemonic program called ‘instruction / statement list'.

• ST - Problem-oriented language, such as structured text (structured text)

• LAD - Ladder Diagram to create a program mnemonic.

• FBD - Block diagram as represented by function block diagram.

• SFC - Flow chart as represented by the sequential function chart (sequential function chart) as

function block diagram.

CONCEPT OF LADDER DIAGRAMBekalan Kuasa Bekalan Kuasa

Motor

Relay

Coil

Relay Contact

Relay Coil

Motor

Appearance of a ladder

Simple Electric Circuit

Bekalan Kuasa Bekalan Kuasa

MotorRelay A

Coil

Relay B

Coil CA

RA

Motor

Simplified to LAD

RB

CB

Suis B

Suis A

CA

RA

Motor

Appearance of a ladder

RB

CB

Suis B

Suis A

LADDER DIAGRAM (LAD) & INSTRUCTION LIST (IL)

10000

END

1000000

01

NL

LD 00

OR 10000

AND NOT 01

OUT 10000

END

LADInstruction List

LD LOAD

LD.NOT LOAD.NOT

AND AND

AND.NOT AND.NOT

OR OR

OR.NOT OR.NOT

OUT OUTPUT

INSTRUCTION LIST & LADDER SYMBOL

20

21

00

00

END

PROGRAM LINE COMMAND INSTRUCTION LIST

INPUT/OUTPUT

000 LD 00

001 OUT 20

002 LD 00

003 OUT 21

004 END

FBD LANGUAGE

& =I0.2

I0.1

Q0.0

>

_

=I0.2

I0.1

Q0.0

&

=

I0.2

I0.1

Q0.0

S

RI0.0

>

_

=

I0.2

I0.1

Q0.0

S

RI0.0

Bit Logic

Bit Logic &

SR Flip-flop

SFC LANGUAGE

START

1N1

1N2

Transition

Action

Action

Initial Step

STRUCTURE TEXT LANGUAGE

THE END