1. Presentation on
Actuators

2. What is an actuator?
Actuators are devices used to produce action or motion.
Input(mainly electrical signal , air, fluids)
Electrical signal can be low power or high power.
Actuators output can be position or rate i. e.
linear displacement or velocity.
Actuation can be from few microns to few meters

3. Actuator functional diagram
Unmodulate
Energy source A
Power amplification
& modulation
Control
signal
Energy conversion
Output
Actuator

4. Hydraulic actuator. Pneumatic actuator. Mechanical actuator.
Types of actuators:
Hydraulic actuator.
Pneumatic actuator.
Mechanical actuator.
Electrical actuator
Linear actuator: solenoid, Hydraulic/Pneumatic.
Rotary actuator: motor, Hydraulic/Pneumatic.

5. Solenoid: A solenoid is a coil wound into a tightly packed helix.
In physics, the term solenoid refers to a long, thin loop
of wire, and wrapped around a metallic core.
which produces a magnetic field when an electric current
is passed through it.

6. Solenoids controlled valves
Application
Pneumatic valve.
Car door openers.
Solenoids controlled valves
Hydraulic cylinder
Single pressure line

7. Types of hydraulic actuator
Hydraulic systems are used to control & transmit power.
A pump driven by prime mover (electric motor) creates flow of fluid
Types of hydraulic actuator
Linear actuator (hydraulic cylinder)-
Provides motion in straight line.
Linear displacement depends on stroke length.
Usually referred to as cylinders, rams (single acting cylinders)
or jacks.
Rotary actuators (Hydraulic motors)-
Produces continuous rotational motion.
Pump shaft is rotated to generate flow.
A motor shaft is caused to rotate by fluid being forced into the driving chambers.

8. Applications Semi rotary actuators-
Produces non-continuous rotational motion.
Limited to less than one revolution (<360°).
Used to produce oscillatory motions in mechanisms.
Applications
Hydraulic jack.
Hydraulic brake.
Hydraulic ram.
Used as sensor.
Close loop velocity controlling.
Highly precise positioning for heavy loads.

9. Pneumatic actuator CONSTRUCTIONAL FEATURES OF CYLINDER
It convert energy formed by compressed air at high pressure
into ether linear or rotary motion.
Quickly respond in operation.
CONSTRUCTIONAL FEATURES OF CYLINDER

10. Hydraulic & pneumatic actuators: cylinders
Single acting:
work can be done only in one direction
Double acting piston:
Work is done in both directions
Plunger
Piston rod on both sides
Piston
Tandem
Telescopic
Telescopic

11. Double acting cylinder with & without cushioning
Non cushioned cylinders
are suitable for full stroke
working at slow speed.
Higher speeds with
external cushions.

12. Rotary hydraulic actuators
Vane rotary actuator:
Parallel piston rotary actuator
Limited angle in both directions.
Maximum angle always smaller than 360°
The same torque in both directions.
Limited angle rotary actuator
Limited angle rotary actuator
Piston rotary actuator:
With rack and gear coupling.
Here maximum angle may be larger than 360°

13. Mechanical actuator Types of mechanics
Mechanical linear actuators typically
operate by conversion of rotary
motion into linear motion.
Types of mechanics
Screw
Wheel and axle
Cam

14. Electrical actuator
Electrically actuated system are very widely used in control system
Working Principle of motor
Every motor works on the principle that when a current-carrying conductor is placed in a magnetic field, it experiences a mechanical force.
There are three types of motor used in control system
D.C. motor
A.C. motor
Stepper motor

15. A.C. motor
Stepper motor
A stepper motor is an electromechanical device which converts electrical pulses into discrete mechanical movements.
Permanent magnet type
Variable reluctance type
Hybrid type

16. Piezoelectric actuators
Pierre and Jacques Curie discovered the piezoelectric effect in 1880.
The application of an electric field to a piezoelectric crystal leads to a
physical deformation of the crystal.
Piezoelectric materials are: Quartz, Ceramics, PZT(lead zirconate
titanade).
Advantages
short response time.
An ability to create high forces.
A high efficiency and a high mechanical durability.
Disadvantage
Have small strains. (0.1-.2%)
High supply voltage needed.( V)
Large hysteresis.(actuator doesn’t go back to exactly where it started).

17. Configuration
A piezo ceramic crystal is coated with silver on both sides.
Glued to a brass, nickel alloy, or stainless steel disk.
Brass:
Commercial & industrial use.(not subjected to environment )
Nickel alloy:
Use where it subjected to environment.
Stainless steel:
Uses where it subjected to solvent, corrosive chemical,
Underwater .
Medical fields.

18. Types of piezoelectric actuators
Piezoelectric Stack Actuators
Produce linear motion.
Linear motor
Piezoelectric bender actuator

19. Other type of actuator
Heaters - used with temperature sensors And temperature controller
to control the temperature in automated moulding
Equipment and in soldering operation.
Lights - Lights are used on almost all machines to indicate the
machine state and provide feedback to the operator.
LED
LCD’s
Gas plasma display
CRT
Sirens/Horns - Sirens or horns can be useful for unattended or
dangerous machines to make conditions well known.