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].