Poster

Week 5 - Finalizing the Project

After referencing the code that our supervisor gave us and the one we got on the mbed website, we wrote our own code for controlling the stepper motor.

After checking with our supervisor, he said that our codes was good to go and it will run the motor and control it with few minor notes on the code.

Figure1: The whole circuit of stepper motor control

Figure 2: The mbed is running at speed 1, and clockwise

Figure 3: The mbed is running at speed 3 and anti-clockwise

Since the software part of our project had been finished, we should connect the whole circuit and test the experiment results. figure 1 shows the whole circuit of what we connected in the lab. There are four outputs from the mbed, they are at pin 23, 24, 25, 26. We connected the four inputs from the amplifier circuit to the four outputs from the mbed. All the pins on the vero-board for the amplifier circuit had been labeled on the wires which makes it easier for us to connect the circuit. For the pins on the circuit amplifier, the GND, current sense A and B should be connected to the ground. The enable A and B and the logic supply Vss should be supplied with 5V DC. For the supply voltage Vs, it should be connected to another power supply which should be less than 46V.

Week 4 - Week activities and Lab Day

At the beginning of week 4, we planed to modify the codes for better controlling of the stepper motor. On the website of the mbed, which is mbed.org, we can use the online compiler to write the codes for the mbed and then compile it. If the code is compiling without any errors, we can compile the code to run the mbed processor and then controlling the motor. 

At the start none of the group members had any thoughts on how to write the codes for the stepper motor. Therefore, we used the online compiler library to get some ideas. We found that there is a simple program called stepper_motor_control. This is a very simple codes, it can just run the four steps of the motor without any control of the speed, direction, and the display on the LCD screen.

Figure 1: codes for the example in the online compiler

figure1 displays the code we got from the mbed library. We can only use the part that includes the steps in our codes as the controlling process is far more advanced.

Then, we tried this program to check whether it can work for our project. However, it was the first time for us to use the mbed, we didn't know how to use the compile file. Therefore, we asked to meet with our supervisor to ask for help. Our supervisor told us that we should copy the successful file into the file of the mbed. And then, we pressed the reset on the board to run the new input codes. To make us more familiar to the pot on the board, he gave us an example codes of using two pots from the mbed website. Then, for our codes, we got an idea of how to design the code using two pots for controlling the speeds and the direction of the stepper motor.

Figure 2: The codes for example of how to use the pot on mbed

Figure 2 was the codes from our supervisor for us to get the knowledge of how to use the pots on the mbed.

Week 3- Lab day

Here we are, fresh and ready to start. The group decided to work on the code inputs for the newly made Stepper Motor circuit.
An example code was compiled into the mbed processor to check whether the different characteristics of the ARM processor will suit our proposed ideas for the new code or not, as well as to gain an insight on the different potentiometers on the processor. The example code was also used to check whether our circuit is ready or not. Proper marking of every wire was used for the purposes of labelling to avoid confusion while connecting the circuit.

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Figure2

Figure3

Figure4

Figure5

Figure6

Finally, we are completed with the circuit and the software part. Many efforts were put in it. Clamping diodes were placed accordingly on the circuit. Figure1 and Figure2 shows our complete circuit.

After that we connected the motor with it which is shown in Figure4. The ARM mbed processor was then connected with the rest of the components. Complete circuit can be seen in Figure4.

Now the task was to check it with a PC. The mbed has an online compiler which provides example codes to facilitate the coding process. We tested it and it worked with no problems.    
On the other hand, a group discussion was made about the poster design for the project. The plan for the upcoming two weeks was to spend time on the poster and finalising the project.                                                                                                                                                                                                                                                                                                                                                                                                           

Week 2- Week 3

After designing the circuit, our team decided to work on the software part as our project is divided equally between both. The ARM mbed processor was plugged in to the computer. Now the task was to programme it. So the team decided to work on different codes and come up with new ideas on the lab day.

Week 2- Lab Day

The morning work is calling and everyone is feeling fresh and energetic. We arranged our components as needed. Today's task was to design the full circuit. We used the circuit design made on the paper and started to make the circuit that contained the amplifier along with it's components as shown below on the data sheet of the L298N bridge.

                                                      L298N Amplifier Circuit

Our circuit is ready to be connected with the stepper motor. This will enable us to connect the whole circuit with a PC.

Week 1-Week 2 (Mid-Week Activities)

Everyone is enthusiastic about the project. All group members did their assigned tasks. During the week, We arranged two meetings in order to check the progress. Most of the group members came up with new ideas about the project. Before starting to build the proper circuit, sketch circuits were made on a piece of paper. This was done by the group member Ba Lei. Following is the pictures for the sketches.

Layout circuit-Capacitors,resistors and diodes

We were ready to make up the circuit on the lab day. Everything was planned ahead and ready to be executed.