DCSERVO MOTORGROUP MEMBERS:1. Adnan Rabbani2. Sohail Naseem3. Danish Ali4. Tanveer Rashid
1.DEFINITION                    2.TYPES AND                      CONSTRUCTION                       3.WORKINGPRESENTATION ...
2.TYPES AND                         4.EQUIVALENT  1.DEFINITION          CONSTRUCTION                                      ...
4.EQUIVALENT     1.DEFINITION                          3.WORKING                     2.TYPES AND                          ...
4.EQUIVALENT     1.DEFINITION                              3.WORKING                        2.TYPES AND                   ...
4.EQUIVALENT       1.DEFINITION                                              3.WORKING                                 2.T...
4.EQUIVALENT      1.DEFINITION                                3.WORKING                          2.TYPES AND              ...
4.EQUIVALENT     1.DEFINITION                           3.WORKING                      2.TYPES AND                        ...
4.EQUIVALENT    1.DEFINITION                  3.WORKING                    2.TYPES AND                   CIRCUIT     5.CON...
4.EQUIVALENT    1.DEFINITION                     3.WORKING                     2.TYPES AND                     CIRCUIT    ...
2.TYPES AND                                                4.EQUIVALENT      1.DEFINITION                                 ...
2.TYPES AND                                               4.EQUIVALENT      1.DEFINITION                                  ...
1.DEFINITION                     2.TYPES AND                                   3.WORKING   4.EQUIVALENT                   ...
2.TYPES AND                              4.EQUIVALENT     1.DEFINITION                             3.WORKING              ...
2.TYPES AND                                   4.EQUIVALENT       1.DEFINITION                                       3.WORK...
2.TYPES AND                4.EQUIVALENT     1.DEFINITION                   3.WORKING                     CONSTRUCTION     ...
2.TYPES AND                          4.EQUIVALENT     1.DEFINITION                          3.WORKING                     ...
2.TYPES AND                4.EQUIVALENT 1.DEFINITION                    3.WORKING                  CONSTRUCTION           ...
2.TYPES AND                                    4.EQUIVALENT  1.DEFINITION                                     3.WORKING   ...
Servo presentation
Servo presentation
Upcoming SlideShare
Loading in …5
×

Servo presentation

1,022 views

Published on

Published in: Education
0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
1,022
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
100
Comments
0
Likes
2
Embeds 0
No embeds

No notes for slide

Servo presentation

  1. 1. DCSERVO MOTORGROUP MEMBERS:1. Adnan Rabbani2. Sohail Naseem3. Danish Ali4. Tanveer Rashid
  2. 2. 1.DEFINITION 2.TYPES AND CONSTRUCTION 3.WORKINGPRESENTATION 4.EQUIVALENT CIRCUIT LAYOUT 5.CONTROLS 6.USES 7.ADVANTAGES AND DISADVANTAGES
  3. 3. 2.TYPES AND 4.EQUIVALENT 1.DEFINITION CONSTRUCTION 3.WORKING CIRCUIT 7.ADVANTAGES & 5.CONTROLS 6.USES DISADVANTAGES1.DEFINITION:A servomotor (servo) is an electromechanical device inwhich an electrical input determines the position of thearmature of a motor. Servos are used extensively inrobotics and radio-controlled cars, airplanes, and boats.
  4. 4. 4.EQUIVALENT 1.DEFINITION 3.WORKING 2.TYPES AND CIRCUIT 5.CONTROLS CONSTRUCTION 6.USES 7.ADVANTAGES & DISADVANTAGES2.TYPES AND CONSTRUCTION:TYPES:There are two main types of servo motor: 1. Linear servo motorI. Brush DCII. Brushless DC 2. Rotary servo motor I. Brush DC servo motor II. Brushless DC servo motor
  5. 5. 4.EQUIVALENT 1.DEFINITION 3.WORKING 2.TYPES AND CIRCUIT 5.CONTROLS CONSTRUCTION 6.USES 7.ADVANTAGES & DISADVANTAGES2.TYPES AND CONSTRUCTION:TYPES:1. LINEAR SERVO MOTOR: A linear servo motor is a flattened out Servo Motor where the rotor is on the inside, and the coils are on the outside of a moveable u-channel
  6. 6. 4.EQUIVALENT 1.DEFINITION 3.WORKING 2.TYPES AND CIRCUIT 5.CONTROLS CONSTRUCTION 6.USES 7.ADVANTAGES & DISADVANTAGES2.TYPES AND CONSTRUCTION:TYPES:I. Linear Brush DC:1. The brushed linear servo motor is designed for long stroke servo applications. It is ideal for direct linear motion without mechanical linkages in closed-loop position packages.2. The moving permanent magnet brush commutated DC linear motor consists of a stationary primary and a moving secondary.3. The stationary primary is a steel laminated core, with multiple coils inserted into insulated slots. The ends of each coil are connected to a commutator bar that is mounted on an aluminum angle.4. The moving secondary features multiple permanent magnets and brushes for commutation. A cable supplies power to the moving secondary. Mounting holes are located on both the primary and secondary.5. The magnetic-attractive force between the primary and secondary can be used as a magnetic preload for the bearing system.6. The customer-supplied bearing system must maintain an air gap of 0.064 cm [0.025 inch] between the primary and secondary. The brush linear motor is available in different cross sections to meet different force requirements.
  7. 7. 4.EQUIVALENT 1.DEFINITION 3.WORKING 2.TYPES AND CIRCUIT 5.CONTROLS CONSTRUCTION 6.USES 7.ADVANTAGES & DISADVANTAGES2.TYPES AND CONSTRUCTION:TYPES:2.Linear BrushLess DC :Brushless needs AC 3 phase supply for working.But someBrushless DC also available, for these motors electronic circuitry isavailable to provide 3 phase supply.
  8. 8. 4.EQUIVALENT 1.DEFINITION 3.WORKING 2.TYPES AND CIRCUIT 5.CONTROLS CONSTRUCTION 6.USES 7.ADVANTAGES & DISADVANTAGES2.TYPES AND CONSTRUCTION:TYPES:2.Rotary servo motor:A rotatory servomotor is a rotatory actuator that allows forprecise control of angular position.
  9. 9. 4.EQUIVALENT 1.DEFINITION 3.WORKING 2.TYPES AND CIRCUIT 5.CONTROLS CONSTRUCTION 6.USES 7.ADVANTAGES & DISADVANTAGES2.TYPES AND CONSTRUCTION:TYPES:2.Rotary servo motor:1.Rotary brush DC servo motor:
  10. 10. 4.EQUIVALENT 1.DEFINITION 3.WORKING 2.TYPES AND CIRCUIT 5.CONTROLS CONSTRUCTION 6.USES 7.ADVANTAGES & DISADVANTAGES2.TYPES AND CONSTRUCTION:TYPES:2.Rotary servo motor:2.Rotary brushless DC servo motor:
  11. 11. 2.TYPES AND 4.EQUIVALENT 1.DEFINITION 3.WORKING CONSTRUCTION CIRCUIT 7.ADVANTAGES & 5.CONTROLS 6.USES DISADVANTAGES3.WORKING:1. The servo motor has some control circuits and a potentiometer (a variable resistor, aka pot) that is connected to the output shaft.2. The potentiometer allows the control circuitry to monitor the current angle of the servo motor. If the shaft is at the correct angle, then the motor shuts off.3. If the circuit finds that the angle is not correct, it will turn the motor the correct direction until the angle is correct.4. The output shaft of the servo is capable of travelling somewhere around 180 degrees. Usually, its somewhere in the 210 degree range, but it varies by manufacturer.5. A normal servo is used to control an angular motion of between 0 and 180 degrees. A normal servo is mechanically not capable of turning any farther due to a mechanical stop built on to the main output gear.6. The amount of power applied to the motor is proportional to the distance it needs to travel.7. So, if the shaft needs to turn a large distance, the motor will run at full speed. If it needs to turn only a small amount, the motor will run at a slower speed. This is called proportional control.
  12. 12. 2.TYPES AND 4.EQUIVALENT 1.DEFINITION 3.WORKING CONSTRUCTION CIRCUIT 7.ADVANTAGES & 5.CONTROLS 6.USES DISADVANTAGES3.WORKING:1. The control wire is used to communicate the angle.2. The angle is determined by the duration of a pulse that is applied to the control wire. This is called Pulse Coded Modulation.3. The servo expects to see a pulse every 20 milliseconds (.02 seconds). The length of the pulse will determine how far the motor turns.4. A 1.5 millisecond pulse, for example, will make the motor turn to the 90 degree position (often called the neutral position).5. If the pulse is shorter than 1.5 ms, then the motor will turn the shaft to closer to 0 degrees.6. If the pulse is longer than 1.5ms, the shaft turns closer to 180 degrees.
  13. 13. 1.DEFINITION 2.TYPES AND 3.WORKING 4.EQUIVALENT CONSTRUCTION CIRCUIT 7.ADVANTAGES & 5.CONTROLS 6.USES DISADVANTAGES4.EQUIVALENT CIRCUIT:
  14. 14. 2.TYPES AND 4.EQUIVALENT 1.DEFINITION 3.WORKING CONSTRUCTION CIRCUIT 7.ADVANTAGES & 6.USES 5.CONTROLS DISADVANTAGES5.CONTROLS:Control Pulse :Control pulse is referred to the type of pulse used toposition the shaft. Two main types of control pulses used inRC applications: center position in 1-2 ms and 1,25-1,75ms.for ServosFor servos pulse width modulation does not control power butinsteadsends information. In this case the frequency is 50 hzcorresponding toa period of 20 ms, the pulse is varied from 1 ms to 2 ms. Thepulsewidth represents the amount of rotation we want from the servo.( Theduty cycle is from 2% to 4% for a servo. )
  15. 15. 2.TYPES AND 4.EQUIVALENT 1.DEFINITION 3.WORKING CONSTRUCTION CIRCUIT 7.ADVANTAGES & 6.USES 5.CONTROLS DISADVANTAGES5.CONTROLS:Control Pulse : Arduino and Pulse Width ModulationThere are many ways to do pulse width modulation with an arduino.These fall into 2 classes, hardware assisted and straight software.HardwareThe arduino hardware includes a unit that will produce pulse widthwith essentially one command, and keep doing it with no attentionfrom the program. However this is easiest if the frequency is kept toabout 500 Hz and with 256 divisions of the duty cycle ( in about .004percent steps ). It is not really useful for servos as the frequency is notright and the control over the 1 to 2 ms range is not very high.SoftwareSoftware modulation keeps the controller busy but allows pretty muchany frequency and duty cycle within a few micro seconds. It can fail ifthe controller gets too busy, and it can be hard for the controller to doother things at the "same time“
  16. 16. 2.TYPES AND 4.EQUIVALENT 1.DEFINITION 3.WORKING CONSTRUCTION CIRCUIT 7.ADVANTAGES & 6.USES 5.CONTROLS DISADVANTAGES5.CONTROLS:Feed back control:
  17. 17. 2.TYPES AND 4.EQUIVALENT 1.DEFINITION 3.WORKING CONSTRUCTION CIRCUIT 7.ADVANTAGES & 6.USES 5.CONTROLS DISADVANTAGES5.CONTROLS:Proportional Integral Derivative (PID) controllers:PID Controller is a feed-back loop unit in the industriescontrol. The controller receives the command, subtracts itwith the actual value to create a “difference”. Thisdifference is then used to calculate a new input valuewhich allows the data of system to achieve or maintain atthe reference value. PID Controller. A PID feedback loopcan maintain the system stability, but other controlmethods may lead to system that have stability errors orrepeated process.
  18. 18. 2.TYPES AND 4.EQUIVALENT 1.DEFINITION 3.WORKING CONSTRUCTION CIRCUIT 7.ADVANTAGES & 5.CONTROLS 6.USES DISADVANTAGES6.Uses:1. In industry Robots2. Inkjet printers3. RC helicopters4. Toys
  19. 19. 2.TYPES AND 4.EQUIVALENT 1.DEFINITION 3.WORKING CONSTRUCTION CIRCUIT 5.CONTROLS 6.USES 7.ADVANTAGES &7.Advantages & Disadvantages: DISADVANTAGESAdvantages:the low energy requirements (efficiency), the high torque,TTL voltage level control, and even the physical properties –servo motors are relatively small sized and have a lowweight.Disadvantages:1) Requires "tuning" to stabilize feedback loop.2) Motor "runs away" when something breaks. Safety circuits required.3) Complex. Requires encoder.4) Brush wear limits life to 2,000 hrs. Service is then required. This systemcauses friction between the brush and commutator, which requires replacingand maintenance5) Peak torque is limited to a 1% duty cycle.6) Motor can be damaged by sustained overload.7) Bewildering choice of motors, encoders, servo drives.8) Power supply current 10 times average to use peak torque. See (5).9) Motor develops peak power at higher speeds. Gearing often required.10) Poor motor cooling. Ventilated motors are easily contaminated.

×