Sunday, 2 September 2012

Week 6: FYP1:-Chapter 2 (Literature Review)

LITERATURE REVIEW

This session discuss on the overall project theory and concept. The purpose of this is to explain the perspective and method that is used in previous research or project and to classify how much this project related with those research and theory. Moreover, this session will show the theory and concept used to solve problem. Theoretical is very important as a guidelines in doing any kind of research.

1) SELECTION OF CONTROLLER 

After researching on the various types of controller, two have been shortlist:-


Type
Voltage
PLC
Need at least 24 volt to operate system
PIC microcontroller
Need at least 5 volt to operate system

A microcontroller is a highly integrated chip which performs controlling functions. A microcontroller, or embedded controller, is similar to a microprocessor as used in a personal computer, but with a great deal of additional functionally combined onto the same monolithic semiconductor substrate. Microcontrollers, sometimes referred to as one-chip microcomputers, are used to control a wide range of electrical and mechanical appliances. Since they were first introduced, microcontrollers have involved to the point where they can use for increasing complex applications. Some microcontrollers in use today are also programmable, expanding the number of application in which they can be used [2]. The PIC microcontroller is chosen one because PIC only needs 5 Volt supply voltage to operate compared to PLC (Programmable Logic Control) that requires a higher voltage which is 24 volt. In addition, the price of PIC microcontroller is much cheaper compared to the PLC.


2) SELECTION OF SENSOR

A sensor is a device which measures a physical quantity and converts it into a signal which can be read by an observer or by an instrument. Because sensors are a type of transducer, they change one form of energy into another. For this reason, sensors can be classified according to the type of energy transfer that they detect. Soil moisture measurements provide useful information for agriculture, such as grape growers, soil stability monitoring, dam monitoring and construction activities.

A typical greenhouse contains several sensors form measuring humidity, temperature, pressure, carbon dioxide, light, motion, etc, and contains several actors, such as, air conditioners, floodlights, sprinkler and water management facility, plant decks, air blowers, fans, CO2 production units, etc. In this project will only consider the LDR light, temperature and humidity sensor of the greenhouse [3].

 2) SELECTION OF WATER FLOW

 

To make the watering system to be better, these system use the aquarium pump to change it with the solenoid valve. From the main pipe, the water will be stored in the tank. The tank also has the buoyed to automatically stop the incoming water to the tank or to store it when the tank is empty.  The high pressure water has been needed to flow the water because separate the water using tube pipe. So, because these statements the aquarium pumps already choose to replace with solenoid valve. So, it can give the adequately pressure for the watering system.


2) SELECTION OF WAVELENGTH FOR OPTIMUM GROWTH

 
It shows two absorption maximum in the blue and red portions in the spectrum. Blue is at the high-energy end of the spectrum, so light of this wavelength is responsible for this much excitation and explains the absorption peak in the blue. Red wavelengths are lower in energy and only boost the electron to a lower energy level than can blue light. The blue wavelength it’s able to create food for leaf (vegetative) and makes it essential for the production of strong, thick leaves and stems. While red wavelength stimulates vegetative growth and flowering but if a plant gets too much red light, it will become tall and spindly. Typically it’s too hot to place near enough for the plant to receive adequate amounts of light [4].



Sunday, 26 August 2012

Week 5: FYP1:-Chapter 1 (Introduction)

PROJECT BACKGROUND

Water is the most important element in our life. Without it, we cannot survive. Watering system can be defined as a system to deliver water to the plants/crops in a greenhouse. These types vary from simple ones to most sophisticated systems and you have to choose the best suited one for your plants. In short, such system takes care of the water requirements of plants and totally eliminates manual watering.

One of the major factors influencing crop growth is the temperature. Different crop species have different optimum growing temperatures and these optimum temperatures can be different for the root and the shoot environment and for the different growth stages during the life of the crop. If a greenhouse were like a residential or commercial building, controlling the temperature would be much easier since these buildings are insulated so that the impact of outside conditions is significantly reduced. A high relative humidity (above 80-85%) should be avoided because it can increase the incidence of disease and reduce plant transpiration [1].

In keeping abreast technology, Development of Humidity Control and Automatic Greenhouse Watering System is created.  This project is constructed to provide opportunity the gardener to manage their crops.  The heart of this project is microcontroller. This system has capability to control the watering system, LDR Light sensor, temperature and humidity in a greenhouse environment. Three sensors are used in this project. Temperature sensor will measure the condition in a greenhouse. The high temperature levels have to increase productivity, quality and earliness. Humidity sensor will be used as it is capable of detecting humidity levels. Most greenhouse plants tend to grow better at higher relative humidity. The LDR light sensor is needed to detect the lighting conditions in a greenhouse. It is able to turn on artificial lighting when there is insufficient light.

PROBLEM STATEMENT

Watering system is the most important thing on a greenhouse system. The water we provide, which is the main element, will make sure the plants survive on certain circumstances. As we all know, most of the gardener use the manual system to water their plant but this system is not efficient. The plants will either die if there is not enough water supplies to the plant or vice versa. Each plant species has an optimum temperature range. Heating devices will maintain the temperature within that range during periods of cold weather. Many greenhouse crops are bred for higher humidity. If grown outside, in lower humidity environments, they usually perform poorly.

In order to maintain the condition and overcome the problem, the development of humidity control and automatic greenhouse watering system is used. This system is created to reduce the time if using automatic system rather than manual way of watering. In other side, temperature and humidity sensor will control the condition in a greenhouse. For example, where temperature sensor detects is too hot condition in a greenhouse then microcontroller will send the signal to the cooling fan to maintain condition in a greenhouse. Fewer workers are needed to maintain the plants. 

OBJECTIVES

The objective of this project is to design and develop  humidity control and automatic greenhouse watering system. This system are allow  to control the amount of water delivered to the plants when it is needed based on types of plants. It also can detect and control the temperature and relative humidity in a greenhouse. 

PROJECT SCOPE 

This project is about controlling system which is control the humidity and also watering system. Sensor used to control the temperature, humidity and lighting condition in a greenhouse.  The aquarium pump is used to supply water to the plant in a greenhouse when it needed. Other than that, the controller (PIC16F877A) as a main part in this project is used to control overall system in a greenhouse. All the part involves in a greenhouse will be control by PIC.