The document discusses the development of computer technology for controlling devices. It describes how programmable logic controllers (PLCs) and microcontrollers can be used with feedback and open-loop control systems along with input/output devices to control industrial applications, vehicles, medical equipment, security systems, and more. A wide range of sensors are also summarized such as temperature, light, motion, pressure, and others that can be used as inputs to computer-controlled systems.

1. Development of Computer
Technology for Controlling
Devices

10. Programmable logic controller
PLC

15. Personal Computer
Microcontroller
Programmable logic
controller PLC

16. (a) Feedback Control System and
(b) Open-Loop Control System

20. InterfaceBoard
EmptyLowHalfFull
DI3
DI2
DI1
DI0
DO3
DO2
DO1
DO4
Closed
Closed
Open
Open
High
DO0

24. Computer control of AC devices

27. RS-232 Serial Port

33. USB
• Fast
• Bi-directional
• Isochronous
• low-cost
• dynamically attachable serial interface
• consistent with the requirements of the PC
platform of today and tomorrow

34. Taxonomy of Application Space

35. Physical Interface
pin Name Descryption
1 Vcc +5 Vdc
2 D- Data-
3 D+ Data+
4 GND Ground

38. Input / Output
Devices

40. Choosing a Sensor

41. Temperature Sensor
• Resistance temperature
device.









0
11
0
00 )]T-(T1[
TT
eRR
RR



42. Accelerometer
• Accelerometers are used to
measure along one axis and is
insensitive to orthogonal directions
• Applications
– Vibrations, blasts, impacts, shock
waves
– Air bags, washing machines, heart
monitors, car alarms
• Mathematical Description is
beyond the scope of this
presentation. See me during lunch
if interested
Vibrating Base
m
k b
Position Sensor

43. Light Sensor
• Light sensors are used in
cameras, infrared detectors,
and ambient lighting
applications
• Sensor is composed of
photoconductor such as a
photoresistor, photodiode,
or phototransistor p n
I
+ V -

44. Sensors (v.1c)44
Infra-red Range detectors by SHARP (4 to 30cm)
• An emitter sends out light pulses. A small
linear CCD array receives reflected light.
• The distance corresponds to the triangle
formed.

45. Magnetic Field Sensor
• Magnetic Field sensors
are used for power
steering, security, and
current measurements
on transmission lines
• Hall voltage is
proportional to
magnetic field
x x x x x x
x x x x x x
x x x x x x
+ + + + + + + + + + + + + + +
- - - - - - - - - - - - - - -
I (protons) +
VH
-
B
tqn
BI
VH




46. Ultrasonic Sensor
• Ultrasonic sensors are used
for position measurements
• Sound waves emitted are in
the range of 2-13 MHz
• Sound Navigation And
Ranging (SONAR)
• Radio Dection And Ranging
(RADAR) –
ELECTROMAGNETIC WAVES
!!
15° - 20°

47. Photogate
• Photogates are used in
counting applications
(e.g. finding period of
period motion)
• Infrared transmitter and
receiver at opposite ends
of the sensor
• Time at which light is
broken is recorded

48. CO2 Gas Sensor
• CO2 sensor measures
gaseous CO2 levels in an
environment
• Measures CO2 levels in the
range of 0-5000 ppm
• Monitors how much
infrared radiation is
absorbed by CO2 molecules
Infrared Source IR Detector

52. •Traffic light controller
•Medical Applications
• BRAIN-COMPUTER INTERFACES
•Virtual Reality
•Industrial Applications
•Security systems
•Aircraft controller
•Military application
•Cars
•Robotics
•Fire alarm system

53. •Traffic light controller

58. •Medical Applications

59. Pulse Oximeter

62. BRAIN-COMPUTER INTERFACES

67. •Virtual Reality

71. Industrial Applications

74. Industrial Automation - Machines
• Storage Systems
• Handling Systems
• Assembly Lines
– Assembly Cells
– Machines
• Actuators
• Sensors
• Production Lines
– Production Cells
– Machines
• Actuators
• Sensors

75. Industrial Automation - Computing
Computers
Controllers
Actuators
Sensors
Software

81. •Security systems

85. •Aircraft controller

88. •Military application

91. A 3-Dimensional Problem
Horizontal Reference Plane
Line of Sight
Target
Elevation
Gun
Elevation

92. •Cars controlling

96. •Robotics

97. Fire alarm system