Design & Manufacturing an Inclined Elevator

Presentación del tema: "Design & Manufacturing an Inclined Elevator"— Transcripción de la presentación:

1 Design & Manufacturing an Inclined Elevator
United Arab Emirates University College of Engineering Design & Manufacturing an Inclined Elevator Ali Hussain Mohammed Obaid Habib Al-Saffar Project Advisor : Prof. Kamal Moustafa Second Semester 2005/2006

2 Outline Introduction Objectives Mechanical system Control system
Results and discussion Conclusion

3 Introduction An elevator is a transporting device used to move goods or people vertically, horizontally or inclined. Inclined elevators are used in such places that can not use vertical space or used by disabled persons that can not use an escalator.

4 Objectives GPI GPII Carrying out complete dynamic force analysis.
Applying engineering sciences. Designing elevator components such as brakes, roping system, buffers … etc. GPII Selecting proper components according to the design analysis. Building a prototype with control devices.

5

6 Mechanical System Counterweight Car Selection of suspension rope Door
Traction drive Elevator machine Car Door Guiding rails

7 Real Design Layout

8 Scaling Scaling can be defined as the determination of the interdependency of variables in a physical system. Advantage Used in solving cost effective problems. A model was made with same geometric, kinematics and dynamic similarities as the real design. The selected scaling factor was 1000:88.

9 2D AutoCAD drawings

10 Cont.

11 Cont. (Cabin) Cabin mass= 1.13 Kg

12 Cont. (Counter-weight)

13 3D AutoCAD drawing

14 Prototype pictures

15 Motor recalculation

16 Control System Objectives: Controlling DC motor (Up, Down).
Controlling motor acceleration & deceleration. Controlling level stops. Operating system accessories (fan, light and door-lock).

17 Closed-loop control diagram

18 Sensor Rotary optical encoder 256 pulses.
It is a digital electronic device used to convert the angular position of a shaft to a number of pulses. 256 pulses. The input voltage is 5 volts.

19 Cont. Coupling Sensor

20 Control device Microcontroller unit (MCU): Advantages:
Defined as a computer on a chip which is used to control electronic devices. Advantages: A microcontroller unit can be a powerful tool when building electro-mechanical systems. It interacts with both hardware and user.

21 Atmega8 (MCU( 8-Kbyte self-programming Flash. Two timers.
28 Input and Output Pins. Input voltage between 4.5 to 5.5 V. Output current is equal to 40 mA. Operating at 4 MHz frequency.

22 Atmega8 (MCU( Pins Diagram

23 Actuator Motor speed control:
A PWM technique works by making a pulsating DC square wave with a variable on-to-off ratio.

24 Duty cycle The duty cycle of the pulses exiting the MCU was calculated as following:

25 Motor direction controller
How does a motor turn in two directions ? By two ways: Manually. Automatically by a computer or a microprocessor.

26 Bipolar junction circuit
H-bridge technique has four switching elements at its corners and the motor forms the cross bar.

27 Cont.

28 Relay H-Bridge

29 Relay operation A current flows through the coil, the resulting magnetic field attracts the armature. The movement either makes or breaks a connection with a fixed contact. When the current to the coil is switched off, the armature is returned to the first position. At the switching off action, the collapsing magnetic field will generate a spike of current that could damage the rest of the circuit.

30 Single Pole Double Throw (SPDT)
Used to reduce the number of relays from four to two. Two relays with 20A current each were used.

31 Circuit components Opto-coupler
An opto-coupler is an optical link and it connects two circuits via this link. Used as insulation and a switch for any circuit.

32 Cont. Transistor array MOSFET power transistor
Used to increase the current level in order to operate the relays (amplifier). MOSFET power transistor Supplies 110 A current to the motor.

33 Cont. Crystal filter It provides a very exactly defined centre frequency which leads to stabilize the input frequency. Supply frequency equals to 4 MHz. Voltage regulator Automatically maintains a constant voltage level Supplies 5 V after changing it from 12 V.

34 Cont. And Gate A logic gate is an arrangement of controlled switches used to calculate operations in digital circuits. It is a multiplication operation between the three input variables (A,B and D). Input 1 Input 2 Input 3 Output 1

35 Cont. Diode Seven-segment display
It allows an electrical current to flow in one direction. Seven-segment display A method of displaying decimal numeric feedback on the internal operations of devices.

36 Printed circuit board (PCB)
Used to mechanically support and electrically connect electronic components using conductive pathways made from copper sheets on a non-coductive material. PCBs are inexpensive, fast, and consistent in high volume production.

37 Power supplying and direction schematic

38 Power supplying and direction circuit

39 MCU schematic

40 MCU circuit

41 Complete control system circuit

42 BASIC COMPILER

43 Cont

44 Cont

45 Results & Discussion Cycle period:

46 Cont. Acceleration operation

47 Cont. The obtained frequency from the oscilloscope was equal to 1.9 KHz. The percentage error between the theoretical and experimental values was equal to 5%.

48 Cont. The velocity of the cabin was measured experimentally after the acceleration and before the deceleration operation periods.

49 Cont. The percentage error of velocity was equal to 13%.
This error was formed by two factors; The slip between the rope and the sheave groove. Random error.

50 Conclusion All objectives of the project were met.
Modifying the project can be done by two ways: Adding limit-switch at each floor. Enhancing the sheave contact area with the rope (V-groove).