Week 3 - Week 4 (FYP II): The DC Motor Circuit

Objective: To identify the DC motor to be used

Analysis/Procedure:

The main purpose of the DC motor used in this project is to rotate the needle of the speedometer. There are few problems to choose the DC motor. The first problem is that certain DC motor can only rotate in one direction. Besides that, most DC motors available in the local market have high revolutions per minute type. Furthermore, each type of DC motor have different power supply voltage. 

After searching almost a dozen shops in Jalan Pasar, I have the correct DC motor. Below are the pictures of the DC motor.

The chosen motor has the ability to rotate clockwise and counter clockwise. The small but with high torque gear motor which makes it great for applications that require extremely low motor speeds. With 6V power supply, the motor can rotate at a pace of 30 revolutions per minutes. The slow rotation is to simulate the actual speedometer. 

After acquiring the DC motor, now to create a simple circuit to rotate the motor clockwise and counter-clockwise in direction. 

In this project, two push switches needed for clockwise and counter clockwise rotation of the DC motor. A Push Switch is a switch that allows electricity to flow between its two contacts when held in. When the button is released, the circuit is broken, so it is called a non-latching switch. Other forms are push to break which does the opposite, that is, when the button is not pressed, electricity can flow, but when it is pressed the circuit is broken.

Week 2 (FYP II): The GSM Modem

Objective: To investigate the GSM modem

Analysis/Discussion:

Today, I have purchase the TC35i GSM modem for only rm 220. It is the most suitable and compatible to this project. The device is ideal for any kind of applications that involves transmitting and receiving SMS and voice calls. 

The device includes an antenna and a power supply cable. The modem implements the highly reliable Siemens TC35i GSM Engine. This ensures high quality and reliable operation along with compatibility with all standard GSM networks. The modem is supplied in a rugged extruded aluminium enclosure making it suitable for use in a wide range of industrial and demanding environments. The unit connects directly to a Personal Computer (PC) or terminal device via theRS232 Cable interface. The integral SIM card holder accepts standard SIM cards of all  network  operators  in  Malaysia  and perhaps all over  the  world  with network provider.  The  only  other  connections required are  to  6-40Vdc  power  supply and Antenna. 

Week 1 (FYP II): The FYP II Begins

Objective: To introduce the second semester of the final year project

Analysis/Discussion:

The first week of the 7th semester has just begun. At the end of the previous semester, I have successfully submitted the proposal report. Now that the proposal has been approved, now I can start with the prototype. Currently, the equipment I have obtained is only the speedometer. 

Before creating the prototype of this project, I need to plan and try to create circuits needed and then simulate them. This part may be difficult since creating circuits will takes a large portion of my time. 

However, by referring the block diagram of this project, it will makes creating overall circuits of this project clearer. 

List of circuits needed: 

1. 2 switches to rotate the needle of the speedometer clockwise and counter clockwise
2. Two sensor circuits. 
3. 1 micro controller circuits
4. RS232 to TTL converter