Modification Of The Present Day Elevator By Introducing Additional Sensing Features

Introduction

In this age of fast work and efficient technologies, there is always the need of advancements and modifications. There is no acceptance for unnecessary delays or other disturbing conditions. There is no time to waste, so the machines have to be efficient and smart enough to eliminate those disturbing conditions and make it more useful and better for the human use. One of such machines is the elevator/lift, which is used by the people all over the world in today’s time. The elevator enables us to move to specific floors of any building without much human work like climbing stairs. Today elevators are used in offices, educational institutions, malls etc. Today’s elevators have a lot of benefits but as a coin has two sides, the elevator has its cons too. There are always some things which stop a machine from being even near to perfect. Here, with this project we try to solve the problems associated with the lift.

These problems are:

• The elevator cabin or car stops at all the floor from where the Hall Call is made irrespective of the presence of anyone outside.
• The elevator stops at the floors even when the maximum weight limit is reached or there isn’t any space left.
• At the hospitals, when a person is in a critical condition and it is needed to take him to the Operation Theatre immediately, then the normal functioning of the elevator may cause serious problems.

These problems result in wastage of time and energy and the system seems to be inefficient in many aspects. Here, we present the solutions to all the above mentioned problems by using new ways with the additional features for the existing elevators. We intent to modify the elevator by making it smarter by introducing additional sensing feature. There can always be further advancements but this project is just about the solutions to the above mentioned problems and we leave the ground open for any new modifications in the future.

Literature Reviews

Design of the Elevator System As the rate of population growth in urban areas increases rapidly, the need for an elevator system increases. The design of the elevator system is an important part of the system. So here are the points related to the design of the elevator system:

1. The relays and IC cards are replaced by the programmable logic controller (PLC) for easy and economical control of the machines used in the elevator. AC motors are used to control the movement of the elevator car without problems due to its advantage of easy control and rapid acceleration and deceleration.
2. The design of the elevator car depends on the number of passengers. It will be accommodated and is done by calculating certain parameters that include the size of the cabin, the rope resistance, the output power and the torque output of the motor. Using the newton formula, you can calculate the force exerted on the string. iii. There are two types of calls in the elevator: receiver call and car call.
3. The programming of the ladder logic diagram is used to implement the entrances and exits of the elevator to move up and back, open and close doors and operate the motors.
4. The system has a simple circuit and has improved the performance of the elevators. Mountain range. The limit switch and push buttons are a major part of the system. They send a signal to the PLC, based on these inputs and the code implemented in it, and generate the appropriate output for the pulley and gate motors. A stepper motor is used to facilitate the movement of the elevator car, since we can establish the number of steps necessary to reach a specific floor.
5. The elevator must conform to the given space requirements of the industrial / building area. It must be large enough to deal with normal life traffic and to move the necessary objects inside the building. Page 5 of 18 viii. In case of emergency, a separate RUN / STOP manual switch is provided.

Mechanism of the Elevator System

1. To develop an elevator system for controlling and managing passenger traffic when all components and sensors in the group, work together for increasing the performance of the elevator rather than individual. This approaching system directly able to minimize the waiting time and riding time spent by passengers, maximize passengers capacities in a given time as well as optimize power consumption of elevator system.
2. To design an elevator all required specification are to be considered like the availability of the materials chosen for thedesign on the basis of properties such as strength, reliability, thermal considerations, corrosion, wear resistance, safety, weight, shape and size, surface finish, cost of production, Human factor, serviceability lubrication and maintenance.
3. The detailed working of elevator can be explain as follows:
1. When the user presses an elevator button to go up. The car call button sends the call request to the system, locates the target floor that the user wanted to visit.
2. The new entry is added to the list of floors to visit. If the elevator is still, the system determines in which direction the elevator must move to reach its next stop. The system orders that the cabin door be closed. When the door has been closed, the system orders the motor to start moving the elevator, either up or down.
3. As the car cabin moves between the floors, the position detects that the elevator is approaching a floor and sends a notification to the system. The system checks if the elevator should stop on this floor. If so, the system orders the motor to stop. When the elevator has stopped, the system orders that the cabin door be opened. If there are other requests, the elevator visits these floors on the way to the floor requested by the people.

Finally, the elevator reaches the target floor selected by the people. Page 10 of 18 iv. Terminal detention devices (safety device) for safety, measures will be taken to control the movement of the cabin when approaching the landing of the terminal and to avoid passing through the terminal. For this purpose, special speed limitation and stop devices are needed.

1. A speed limiting device of the emergency terminal is required to reduce the speed of the cabin automatically when the car approaches the landing of the terminal. It is independent of the operating device, which controls the control of the lift, and of the normal device for stopping the terminal, in case it cannot reduce the speed of the car as expected.
2. The normal terminal stop device reduces the speed and stops the car at or near a landing terminal regardless of the operation of the operating device. It must continue to operate until the final terminal device stops working.
3. It is required that the final stop device of the terminal automatically interrupts the electrical energy of the engine and the brake of the driving machine after the cabin has passed a terminal landing. But this device should not work when the normal terminal stop device has stopped the cab. If activated, normal cab operating devices should be unable to move the cab.
4. The counterweight is used to maintain traction between the lifting cables and the control pulley. The power requirements of the driving machine to move the cabin are reduced by hanging the counterweight on the lifting ropes. The weight of the counterweight is generally equal to the weight of the unloading cabin and the cables plus approximately 40% of the nominal load capacity of the cabin. A counterweight is usually made of steel plates cut into a steel frame.
5. The simple arrangement of the lifting cables, the cabins and the counterweight, for example, is called a 1: 1 rope because the speed of the cabin is equal to the speed of the rope. The cords are attached to the upper part of the cab frame, wound around the drive pulley, bent towards the deflecting pulley and then extend down to the top of the counterweight. This rope arrangement is also known as a simple wrapping rope because the rope passes over the drive pulley only once between the cab and the counterweight. Page 11 of 18 3. 4 Sensors used in the Elevator System

In the elevator system, we previously used relay and IC cards to control the elevator. And due to the interruption, we have now replaced it with PLC. It is easy to control and the elevator fully automated by PLC.

The relay logic is used to program the PLC. The control operations are carried out as going up and down from one floor to another, opening and closing doors, etc. iii. According to the PLC signal, the implementation of the elevator can be applied in the real world. This result shows that the system is achieving its objectives with a high level of success. It has the potential to reduce the passengers who wait by reducing unnecessary stops for the lift and increases passenger satisfaction.

This will also help reduce unnecessary waste of electricity and energy. This proposed system can be very beneficial for elevators in schools, hospitals and shopping centers.

A series of 32 traditional infrared interrupting sensors and MEMS accelerometer are used to detect the position of the elevator car. The proposed system offers an accurate position and has fast and reliable answers and accuracy to avoid overposition and steady state error.

The proposed system is implemented in such a way that the no. of the passengers who call the elevator to go up, down, waiting for the floor of all the others and, therefore, can make effective decisions to directly stop the elevators. Our systems proposed against a traditional elevator proved to be more efficient in terms of reduced waiting time for passengers in several cases and also unnecessary stops and significant time savings for others.

Proximity sensors are used to detect nearby objects without any physical contact. This sensor will be used on the outside of the elevator just near the elevator door on the floor. This will detect the presence of people outside the elevator. This will help the unnecessary stop of the elevator even after pressing the switch (call button) on that particular elevator.

The magnetic encoder is used to detect the position of the elevator car. The received signal will be converted directly into digital. It has better control properties, precision and satisfaction results.

Methodology And Materials

A PLC is used to control the mechanism of an elevator. The PLC is used to control all sensors connected to it. There are different types of sensors that have been used in this elevator. The elevator will work as before, but with some external features, as it will save time and money. The motors are used to open and close doors, fans, lights, etc.

DC Motor

It is an electrical device used for the conversion of electric power from direct current into mechanical energy. It has inductors inside that produce the magnetic field used to generate movement. The engine is responsible for the movement of the elevator car up and down between the floors. The controller specifies the elevator car to move, sending the signal in which direction to move.

Sensors

Sensors are devices used to detect the presence or absence of people by converting the physical quantity into a signal.

Magnetic Encoder

Here a magnetic encoder is used that will detect the position of the elevator car. As the elevator used is based on rope. The encoder will detect the rotation of the pulley connected with ropes.

Infrared Sensors

The infrared is used to detect the obstacle. These sensors are used to detect the obstacle when the infrared transmitter radiates the signal that reflects the infrared receiver. The radiation emitted by the transmitter is invisible to the human eye. An IR used on the inside of the door of the elevator car, while 3 IRs are used on the outside door, that is, on each floor of the elevator door. The door will open when the inner and outer door exactly match the IR sensors. This will also help to avoid closing the door when someone should still enter the elevator.

PROXIMITY SENSOR

This sensor is used to detect nearby objects without physical contact. This sensor will be used on the outside of the elevator just near the elevator door on the floor. This will detect the presence of people outside the elevator. This will help the unnecessary stop of the elevator even after pressing the switch (call button) on that particular elevator.

Limit switch

This switch is used mechanically linked to the set of contacts. It is a switch that works and is operated by the movement of the part of the machine. As you get closer to the destination floor, it reduces the speed of the elevator car and avoids the jolts and sudden stops that will affect people inside the elevator car.

Push button

It is used to call the elevator cabin. The push button is mentioned implemented on each floor. The switch causes electricity to flow between its two contacts when it is held down and the circuit breaks as it is released.

Conclusion

We come to the conclusion that we have used different methods and sensors such as the magnetic encoder, the proximity sensor, different types of IR sensors, etc. to modify existing elevators to make them more efficient, smart and easy to use, and we have tried to solve unattended problems such as redundant stops, elevator stops despite being full and other irritating problems. According to this report, we only have half the distance at the end of the components that will be used in the hardware model of the system and the understanding of the mechanism and operation of each part. We have focused mainly on the use of the new components used to modify the elevator and add something new. The main objective is the use of different sensors and their operation, which we have completed from now on. We have reviewed several journal articles and conferences of different authors and we have understood the operation of existing elevators and also the functioning of some specific components that can be used in our project. The methods, mechanisms and work have been described with a certain level of clarity that we have up to now and will be updated as we move forward in this process.