Week 4

In week four, the flex sensors were arrived and all previous sections could be connected. All the action modes of car was completed and tested. Moreover, the test of employing Bluetooth to control the car was successful, which means most work of car part was completed. 

Working Details

Motor Group:

Before the lab, we have spent some time at home to writing the codes of the nine running modes, and each of them were tested to ensure they are working. The video of testing is shown below. However, there is a problem that the buttery could not supply enough voltage to run the motors and arduino at the same time. Therefore, a portable power bank was employed to supply power for the car, but it is too heavy for the car. Consequently, another power supply should be found.

Video of testing

In the morning of the lab day we were trying to connect the arduino and phone. At this time, the phone can find the Bluetooth. However, there are still some bugs on it, which results in some errors on the received data. In debugging part, we changed the data type, and the problems were solved. After debugging, phone could control arduino successfully, and they can receive the information transmitted each other.  

In addition, we try to transmit information between two paired hc-05 Bluetooth on arduino, and a LED was employed to determine whether the data was received successfully. However, there are too many bugs, and it was always failed in the morning.  

We solve the data type problems, language problems and logic problems, and a lot of tests were made. As a result, the receiver can receive data, but no matter what the master send it is always 128 or 248 in receiver. At last, we search it on Google and find that somebody had the same problem with us. They solved the problem by change the Baud rate to 9600 and adjust the master to AT mode, and the test with LED was successfully. The codes of master and receiver part are shown in Figure 1 and Figure 2.

Figure 1: The master part of LED test

Figure 2: The receiver codes of LED test

As if can be seen in Figure 1, after pairing, the master Bluetooth will send 1 to receiver, and send 2 after 3 seconds. In the receiver part, the serial will print the information received. In addition, the LED will be lighted if 1 is received, and it will be turned off if 2 is received.

In the next step, we complete the codes of Bluetooth in this project, and combine it with the codes of motor controlling. Moreover, the tests of combined codes were also successful.   

Flex Sensor Group:

We got our flex sensors this week and we were able to connect all parts of our previous work. We measured the resistors of flex sensors and tried to run our codes, all work went smoothly and the software part is basically completed.  

The combination of gloves and sensors is designed and the general circuit diagram is drawn. We started working on hardware. The circuit scenario is shown in Figure 3.

Figure 3. Circuit scenario

We chose four flex sensors and glue them to the four fingers of the glove. Then according to the circuit diagram we designed, the resistors and wires are welded together. One end of each wire is connected to the sensor and the other end is connected to Arduino (Figure 4).

Figure 4. Basic circuit

Tie Arduino to the bottom of the glove with strings and fix the whole model with tape. The hardware work of the glove part has been roughly completed and the final glove is shown in Figure 5. What we need to do next is to connect all parts and make them work smoothly.

Figure 5. Final glove