The document provides an overview of mechatronics. Some key points:
- Mechatronics is a multidisciplinary field that combines mechanical engineering, electronics, and computer science. It aims to design and manufacture products like smart machines.
- A mechatronic system integrates sensors to collect input data, microprocessors to analyze/control the system, and actuators to respond accordingly. Common examples are robots, automobiles, and factory automation equipment.
- Mechatronic systems have evolved from basic integration of electrical/mechanical components to "smart systems" using microprocessors and advanced control strategies. This enables more intelligent, autonomous behavior.
1. MECHATRONICS
ME602
You have played enough with toy models.
Now its time to BUILD some.
Prof. Kumar Naik M
Mechanical Engineering dept,
ACED, Alliance university
2. Introduction
The term “Mechatronics” was coined by Tetsuro Mori, a senior
Japanese engineer at Yasakawa Company in 1969.
The word mechatronics is composed of “mecha” from mechanical
and the “tronics” from electronics.
Mechanical + Electronics = Mechatronics
“Mecha” + “tronics” = Mechatronics
Mechatronics is a multidisciplinary field of science that includes
a combination of mechanical engineering, electronics, computer
engineering, telecommunications engineering, systems
engineering and control engineering.
3. It is in the form of human, has been
programmed for specific function
depending on requirement.
ROBOTICS
The aim of the Mechatronics
4.
5.
6. Origin of the Mechatronic system
The word Mechatronics was coined by Japanese in the late 1970‟s
to describe the philosophy adopted in the design of subsystem of
electromechanical systems.
The field has been derived by rapid progress in the field of
microelectronics.
At R&D level the following areas have been recognized under
Mechatronics discipline.
Motion control actuators and sensor
Micro devices and optoelectronics
Robotics
Automotive systems
Modeling and design
System integration
Manufacturing
Vibration and noise control.
7. Evolution of Mechatronic system
The technology has evolved through several stages that are termed as
levels. The evolution levels of Mechatronics are:
Primary level Mechatronics (first)
Secondary level Mechatronics (second)
Tertiary level Mechatronics (third)
Quaternary level Mechatronics (fourth)
8. Primary level Mechatronics (first)
In the early days Mechatronics products were at primary level
containing devices such as sensors, and actuators that integrated
electrical signals with mechanical action at the basic control level.
Examples: electrically controlled fluid valves
Secondary level Mechatronics (second)
This level integrates microelectronics into electrically controlled
devices.
Examples: cassette player.
9. Tertiary level Mechatronics (third)
Mechatronics system at this level is called ‘smart system’ and the
control strategy includes microelectronics, microprocessor and
other application specific integrated circuits‟ (ASIC).
Examples: DVD player, CD drives, automatic washing
machine, CD drives, etc.
Quaternary level Mechatronics (fourth)
This level includes intelligent control in Mechatronics system. The
level attempts to improve smartness a step ahead by introducing
intelligence and fault detection and isolation (FDI) capability
system.
Examples: artificial neural network and fuzzy logic
technologies.
10. Basic elements of a mechatronic system
Mechanical
system
Electronic
device/Microprocessor
SensorActuator
Sensor: Senses condition of mechanical system. Provides input to
microprocessor for control
Electronic device: Provides signal to actuator
Actuator: Activates mechanical system to bring it to required
condition
13. Sensors
Temperature- thermocouple, thermistors, etc.
Light- light dependent resistors(LDR)
Force- strain gauges
Displacement- potentiometers
Controller
Analyzes the output of the sensor
Decides what have to be done
Command the actuator accordingly
Actuator
Actuates as per the signal from the controller
Led’s , alarms, heaters, etc.
DC/AC motors, servos, solenoids.
14.
15.
16.
17.
18. Examples
Refrigerator
Sensor – Temperature sensor
Controller – Timer and temperature control
Actuator – Fan and compressor
Weighing scale
Purely mechanical: Having spring, rotator, pointer
Mechatronic: Load cell with strain gauge, microprocessor, digital
readout
Temperature controller
Purely mechanical: Bimetallic strip operates on/off switch.
Mechatronic: Thermo-diode sensor, microprocessor controlled
19. Mechanical system V/S Mechatronics system
• Strong, large and heavy
• Repairable
• Reliable
• Design is difficult
• costly
• Light
• Easily reprogrammable
• Less space consuming
• Easy replacement
• Complex to common man
20. Advantages:
• The products produced are cost effective and very good quality.
• Greater extent of machine utilization
• High degree of flexibility
• Greater productivity
• High life expected by proper maintenance.
Disadvantages:
• Higher initial cost of the system
• Requires more expertise
• It is expenses to incorporate Mechatronics approaches to existing/old
systems
• Specific problem of various systems will have to be addressed
separately and properly
26. •Desktop sized Factory
•Build small parts with a small
factory
•Greatly reduces space, energy,
and materials
Mechatronics Systems
-Manufacturing Applications-
Micro Factory
Micro Factory Drilling Unit
28. -Smart Robotics Application-
System Can
•Carry 340 lb
•Run 4 mph
•Climb, run, and walk
•Move over rough terrain
BigDog
Advantages
•Robot with rough-terrain mobility that could
carry equipment to remote location.
Mechatronics Systems
30. •Train Position and Velocity
constantly monitored from
main command center.
•Error margin in scheduling no
more than 30 seconds
•Fastest trains use magnetic
levitation
High Speed Trains
Mechatronics Systems
-Transportation Applications-
JR-Maglev
Top Speed: 574 km/h (357 mph)
Country: Japan
Transrapid
Top Speed: 550 km/h (340 mph)
Country: German
Magnetic Levitation
31. -Transportation Applications-
Advantages
•Simple and intuitive
personal
transportation device
Systems Uses
•Tilt and pressure sensors
•Microcontroller
•Motors
•Onboard power source
Segway
Mechatronics Systems
33. -Space Exploration Application-
System Can
•Collect specimens
•Has automated onboard
lab for testing specimens
Advantages
•Robot that can travel to other
planets and take measurements
automatically.
Mechatronics Systems
Phoenix Mars Lander's
35. -Medical Applications-
•Used by patients with slow or
erratic heart rates. The pacemaker
will set a normal heart rate when it
sees an irregular heart rhythm.
•Monitors the heart. If heart
fibrillates or stops completely it will
shock the heart at high voltage to
restore a normal heart rhythm.
Mechatronics Systems
Pace Maker
Implantable Defibrillation
36. -Defense Applications-
•Advanced technology is making
our soldiers safer.
•Some planes can now be flown
remotely.
Unmanned Aerial Vehicle
Stealth Bomber
Mechatronics Systems
37. -Sanitation Applications-
System Uses
•Proximity sensors
•Control circuitry
•Electromechanical valves
•Independent power source
Advantages
•Reduces spread of germs by making
device hands free
•Reduces wasted water by automatically
turning off when not in use
Mechatronics Systems
38. -Sanitation Applications-
Advantages
•Reduces spread of germs by making
device hands free
•Reduces wasted materials by
controlling how much is dispensed
Systems Uses
•Motion sensors
•Control circuitry
•Electromechanical
actuators
•Independent power source
Soap Dispenser
Paper Towel Dispenser
Mechatronics Systems
40. Washing MachineSolution Power Supply
Rectifiers/Regulator
Pressure Sensor
MPX5006/MPX2010
Mechatronics Systems
-Smart Home Applications-
41.
42.
43. System
System can be thought of as a box which has an input and output.
we are not concerned with what goes on inside the box but only
relationship between the output and input.
45. Measurement system
Measurement system can be thought of as a black box which is used
for making measurements.
It has as its input quantity being measured and its output the value of
that quantity.
47. Measurement system
Three basic elements:
1. Sensor- Responds to the quantity being measured by giving as its
output a signal related to the quantity.
E.g. Thermocouple: input is temperature and output is an emf
related to the temperature value.
2. Signal conditioner- Takes the signal from the sensor and
manipulates it into a condition which is suitable either for display
or for use to exercise control.
E.g. small emf from a thermocouple can be amplified. The
amplifier is the signal conditioner.
3. Display system- where the output from the signal conditioner is
displayed.
E.g. a pointer on a scale or digital readout.
48. Control system
Control system are an integral part of our lives and play very
important role.
From a simple bread toaster to complex power plant, control system
are all around us and inseparable part of modern society.
Launching a satellite in orbit, regulating a power plant, tracking
enemy on radar are some of man made control system.
Control system occur in nature also. Human body is a great example
of complex Control system, because we've so many control system
by nature i.e. respiratory, Digestive system etc.
49. Control system : A control system is an arrangement or a
combination of various physical components, also called sub-
systems, connected in such a manner so as to attain a certain
objective.
Input : The excitation applied to the system from an external
source to attain a output is called input signal.
Output : The actual signal attain from system is called output
signal.
Control action : is a quantity responsible for activating the system.
Basic Block Diagram of Control System
50. Control system
Control some variable to some particular value.
E.g. A central heating system where the temperature is
controlled to a particular value.
Control the sequence of events.
E.g. A washing machine where the dials are set to, say ‘white’
and the machine is controlled to a particular washing cycle.
Sequence of events, appropriate to that type of clothing.
Control whether and event occurs or not.
E.g. a safety lock on a machine where it cannot be operated
until a guard is in position.
51. Concept of feedback
In order to maintain the accuracy of the output, the input may need to
be adjusted using FEEDBACK.
Examples
When body temperature goes below normal, the body is made to
shiver to increase the temperature. Similarly, when temp. goes above
normal, sweating takes place.
52. when you want to pick up the pencil, feedback guides the hand to
the exact spot.
54. Open loop control system
Those systems in which the output has no effect on the control
action are called open-loop control systems. i.e. It doesn’t
automatically correct the changes in the output.
A system in which control action is independent of the output of the
system is called as open loop system.
55. In open loop system, the output remains constant for a given
input provided the external conditions are the same.
There is no connecting action taking place in an open loop
system i.e. No Feedback
56. Examples of Open loop system
Electric Hand Drier
Automatic Washing Machine
Bread Toaster
Advantages
• Simple Construction &
Design
• Economic
• Easy maintenance
• Stability
Disadvantages
• Incorrect and unreliable
• Internal Disturbance
• Recalibration is required time
to time
57. Close loop control system
A system in which the control action is dependent on the output
is called close loop system. In close loop system the output is
constantly monitored and adjusted to the required value by the
system.
The output signal is fed back.
58. Depending upon the difference between the output signal
and reference input, corrective actions can be taken by the
controller to adjust the output.
59. Examples of Close loop system
Automatic Electric Irons
Voltage Stabilizer
DC motor speed control by Tachometer
Missile Launcher
Advantages
• Accuracy is high
• Facilitates Automation
Disadvantages
• Complicated in design and
maintenance costlier.
• Problem of Stability
63. Basic Elements of Closed Loop System
1.Comparison element
2.Control element
3.Correction element
4. Process elements
5.Measurement elements
64. Basic Elements of Closed Loop System
Comparison element
compares the reference value of the variable condition being controlled
with the measured value of what is being achieved and produces an
error signal.
Error signal = reference value signal – measured value signal.
Negative feedback – signal related to the actual condition
being achieved is feed back to modify the input signal to a
process.
Positive feedback – occur when the signal feedback adds to
the input signal
65. Control element
It Decides what action to take when it receives an error signal
Correction element
Produces a change in the process to correct or change the
controlled condition.
Process element
The process that is being controlled. E.g. room whose temperature
is being controlled, tank whose level is being controlled.
Measurement element
Produces a signal related to the variable condition of the process
that is being controlled. E.g. a switch which is switched on when a
level is reached or an emf when a temperature is reached.
66.
67.
68. Analogue and digital control systems
Analogue systems are ones where all the signals are continuous
functions of time and it is the size of the signal which is the a measure
of the variable.
Analogue signal: measures the size of
the variable
69. Digital signal: the value of the variable is
represented as a series of ON/OFF pulses
Digital signals are a sequence of on/off signals, the value of the
variable being represented by the sequence of on/off pulses.
70. Comparison of Analogue & Digital systems
Analogue to digital converter (ADC) and Digital to analogue
converter (DAC) elements are placed in the loops.
So that the microprocessor systems can be supplied with digital
signals for processing and then produce an output which is converted
to an analogue signal to operate the correction units.
Process
Measurement
Control
elementComparison
Reference
value
Correction
elementError
signal
Process
Measurement
Control
elementComparison
Reference
value
Correction
elementError
signal
ADC
DAC
71. Introduction to controllers
Most industrial processes require that certain variables such as flow,
temperature, level or pressure should remain at or near some reference
value, called SET POINT.
The device that serves to maintain a process variable value at the set point
is called a CONTROLLER.
A Controller is a device that receives data from a measurement instrument,
compares that data to a programmed set point, and, if necessary, signals a
control element to take corrective action.
Controllers may perform complex mathematical functions to compare
activities a set of data to set point or they may perform simple addition or
subtraction functions to make comparisons.
Controllers always have an ability to receive input, to perform a
mathematical function with the input, and to produce an output signal.
72. Types of controllers
There are a number of ways by which a control unit can react to an error signal
and supply an output for correcting elements:
Proportional controller
Integral controller
Derivative controller
Proportional Integral controller
Proportional Integral Differential controllers
Microprocessor based controllers
73. Proportional controller
Proportional mode which produces a control action that is
proportional to error. The correcting signal thus becomes bigger, the
bigger the error.
Thus as the error is reduced the amount of correction is reduced and
the correcting process slowdown.
In other words, the output of a proportional controller is the
multiplication product of the error signal and the proportional gain.
75. Contd…
Constant rate of change of error
Time
Error
0
Time
Controlleroutput
0
Constant rate of change of
controller output
76. Integral controller
Which produce a control action that is proportional to the integral
of the error with time.
Thus a constant error signal will produce an increasing correcting
signal.
The correction continues to increase as long as the error persists.
The integral controller can be considered to be ‘looking back’,
summing all the errors and thus responding to changes that have
occurred.
77. Contd…
The rate of change of controller output (I) is proportional to the input
error signal e.
𝑑𝐼
𝑑𝑡
= 𝐾𝐼 𝑒
Where e is the error and KI is a constant of proportionality having the
units 1/s. Integrating we get
𝐼0
𝐼 𝑜𝑢𝑡
𝑑𝐼 =
0
𝑡
𝐾𝐼 𝑒𝑑𝑡
Therefore 𝐼 𝑜𝑢𝑡 − 𝐼0 = 0
𝑡
𝐾𝐼 𝑒𝑑𝑡
Where I0 is the controller output at time 0 and Iout is the output at time t.
79. Derivative controller
Which produces a control action that is proportional to the rate at
which the error is changing.
When there is a sudden change in the error signal the controller
gives a large correcting signal, when there is a gradual change only a
small correcting signal is produced.
Derivative control is not used alone but always in conjunction with
proportional control and often integral control.
80. Contd…
The controller output is proportional to the rate of change with time of
the error signal.
𝐶𝑜𝑛𝑡𝑟𝑜𝑙𝑙𝑒𝑟 𝑜𝑢𝑡𝑝𝑢𝑡 = 𝐾 𝐷
𝑑𝑒
𝑑𝑡
Where e is the error and KD is a constant of proportionality.
As soon as the error signal begins to change, there can be quite a
large controller output.
However, there is no response to steady state errors.
Derivative controllers are therefore combined with proportional
controllers.
82. Proportional plus Integral (PI) control
The integral mode of control is not usually used alone but is
frequently used in conjunction with the proportional mode.
When integral action is added to a proportional control system the
controller output is given by
Where KP and KI are the proportional and integral control constants and
e is the error.
𝑐𝑜𝑛𝑡𝑟𝑜𝑙𝑙𝑒𝑟 𝑜𝑢𝑡𝑝𝑢𝑡 = 𝐾 𝑃 𝑒 + 𝐾𝐼 𝑒𝑑𝑡
83. Proportional plus Integral plus derivative (PID)
control also known as three-mode control
Combining all three modes of control (proportional, integral and
derivative) gives a controller knows as a three-mode controller or PID
controller.
Where KP, KI, and KD are the proportional, integral and derivative control
constants respectively and e is the error.
𝑐𝑜𝑛𝑡𝑟𝑜𝑙𝑙𝑒𝑟 𝑜𝑢𝑡𝑝𝑢𝑡 = 𝐾 𝑃 𝑒 + 𝐾𝐼 𝑒𝑑𝑡 + 𝐾 𝐷
𝑑𝑒
𝑑𝑡
84. Microprocessor based controllers
Hard-wired circuits are now more likely to have been replaced by a
Microprocessor based controlled system,
And sequencing being controlled by means of a software program.
86. Sequential controllers
An illustration of sequential control, consider the domestic washing
machine. A number of operations have to be carried out in the correct
sequence. These may involve:-
A pre-wash cycle when the clothes in the drum are given a wash in
cold water
A main wash cycle when they are washed in hot water
A rinse cycle when they are rinsed with cold water a number of
times.
Spinning to remove water from the clothes
Each of these operations involve a number of steps.
87. Example :- Pre wash cycle involves following steps
Opening a valve to fill the machine drum to thee required level
Closing the valve
Switching on the drum motor to rotate the drum for specific time
Operating the pump to empty the water from the drum.
The operating sequence is called a program , the sequence of
instructions in each program being predefined and built into the
controller used.