Haria Nikunj Jayantilal Orre Liza Maribor Turning LED on/off using motion sensor- A project report

Transcription

1 0 Haria Nikunj Jayantilal Orre Liza Maribor Turning LED on/off using motion sensor- A project report Digital Electronics- APT 2030 Dr. Sylvester Namuye USIU- Africa Spring

2 ABSTRACT The purpose of this experiment was to obtain a basic knowledge on digital electronics and in turn set the stage to perform the analysis and design of complex digital electronics circuits. It also served as an opportunity to learn how the motion sensor worked by using it to turn the LED on/off. This was done by examining results that were brought forth after carrying out the experiment. The results were analyzed and observations made in order to draw accurate conclusions from the entire process. The experiment was carried out on a breadboard and an Arduino, a board used to prototype experimental electrical circuits and by following step by step instructions to build the circuit and to observe the results there after in order to draw conclusions and relationship between the output produced and its logical components from the constructed circuit. The purpose of the Arduino was to control the motion sensor and store the results. The report draws upon mostly primary sources such as the results of the experiment itself and books based on the subject matter it was seen that the circuit is only observed to produce an output of logic high (1) only when there was movement that changed the infrared waves. The circuit only works this way for these inputs. Otherwise it produces an output of logic Low (0). 2

3 Table of Contents ABSTRACT... 2 Table of Contents... 3 INTRODUCTION... 4 OBJECTIVES... 5 REQUIREMENTS... 6 PROCEDURE... 7 OBSERVATIONS AND RESULTS... 8 DISCUSSION CONCLUSION

4 INTRODUCTION Digital electronics is one of the fundamental courses found in all electrical engineering and most computer science programs. It is essential in understanding the wide range of applications from industrial electronics to the field of communication and micro embedded systems with the main and perhaps the most revolutionary advantage being the decrease in physical size and improvement of technology. By definition, Digital electronics, also known as digital circuits, are electronics that handle digital signals, discrete bands of analog levels rather than by continuous analog ranges as used in analog electronics. As a result, Digital techniques are useful because it is easier to get electronic devices to switch into one of a number of known states than to accurately reproduce a continuous range of values. Furthermore, digital electronics circuits are usually made from large assemblies of logic gates that serve as simple electronic representations of Boolean logic functions. These logic gates are arrangements of electrically controlled switches better known as transistors. The logic gates can be used to create combinational logic with each logic gate within the circuit representing a function of Boolean logic, a form of algebra in which all the values are reduced to either true or false. The purpose of this report is to discuss the conclusive results and observations obtained from carrying out an experiment that sought to provide enlightenment on the workings and design of digital electronics by demonstrate the fundamental working of PIR motion Sensor. 4

5 OBJECTIVES The main objective of this experiment was to obtain a basic knowledge on digital electronics and in turn set the stage to perform the analysis and design of complex digital electronics circuits. Furthermore, the experiment sought to acquaint the authors to one of the most fundamental tools needed to learn how to build circuits, the breadboard, a construction base used to prototype electronic circuits electronics, sensors and most important the Arduino. The experiment also sought to benefit the author from the experience acquired from carrying out the task at hand. Through the authors own effort and knowledge acquired from carrying out the experiment, the authors have been enabled to use and adopt the knowledge acquired to so solve future problems that might be encountered by applying what was learnt from the experiment. Through the experiment, the authors were presented with an opportunity to learn how the sensor works by connecting it to the Arduino. The experiment gives the authors the ability to determine the output of the LED, given the input logic signals and as result, enabling the LED s behavior to be observed and understood through experimental determination of the motion sensor. Also, the experiment enabled the authors to understand the workings of some of the most basic circuit components such as resistors, Light Emitting Diodes, source, ground, Arduino and the breadboard as well. It also offered the opportunity to understand how to convert a circuit s schematic diagrams into an actual physical representation of a circuit on to a breadboard. Most importantly, the experiment serves as an introduction to the inner workings of digital computers and modern digital electronics as digital logic is the very core and foundation of digital computers. 5

6 REQUIREMENTS The following electrical components, each used for a specific reason was needed in order to assemble the circuit. 1 Arduino Mega Breadboard 1 LED 1 Switch 2 10 Resistor PIR Sensor Connecting wires Connection to power 6

7 PROCEDURE The schematic diagram below severed as a guide on how to connect the electronic circuit. It depicted where each of the electrical components needed to be placed and how they were to be interconnected with each other in order to assemble the circuit. 7

8 Using the schematic diagram above, the electrical circuit was constructed on a breadboard with the actual electronic components and connections depicted in the diagram. The figure below depicts the actual representation of the circuit s schematic as assembled on a breadboard. OBSERVATIONS AND RESULTS After the circuit was assembled on the breadboard as per the depiction on the schematic, the 8

9 Arduino was powered using a computer and the code was compiled and ran to produce an output. When the PIR motion sensor detected Infrared waves, it would send charge the SSR coil which powered on the lamp. The result is shown in the figure below. 9

10 When there was no motion or no infrared waves being emitted the lamp did not light up as shown in the figure below. 10

11 DISCUSSION The circuit was constructed in basic way with 3 modules, the input, output and the logic. The input was the PIR motion sensor, the output being the lamp and the logic being the code executed in the Arduino. PIR Sensor Input The Arduino Logic Module Lamp Output Module 11

12 CONCLUSION In conclusion the circuit is only observed to produce an output of logic high (1) only when there is infrared waves emission by the human body. The circuit only works this way for these input. Otherwise it produces an output of logic Low (0), for all the other possible combinations. 12