10.03.15 - Building the Parachute

We build a parachute today following this tutorial we found on YouTube. 

We used this formula to find the diameter we needed to make the parachute. 

D = sqrt( (8 m g) / (p r C_d v²) )

Where:

D is the chute diameter in meters
m is the rocket mass in kilograms
g is the acceleration of gravity = 9.8 m/s2
p is 3.14159265359
r is the density of air = 1.22 kg/m3
Cd is the drag coefficient of the chute, which is 0.75 for a parasheet (flat sheet used for a parachute, like Estes rockets), or 1.5 for a parachute (true dome-shaped chute).

v is the speed we want at impact with the ground (3 m/s or less)

D = √((8* .246*9.81 )/(π(1.225*1.5*3^2 ))

The weight of our CanSat was 246g. 

We subbed in the weight of our CanSat into the formula. 

A diameter of 61cm was needed.

Testing the Parachute:

Let it goooooo...!

As you can see, IT WORKS!

12.02.15 - Calibrating the Thermistor

We started off by building a circuit that uses a thermistor to measure the temperature.

Using the instructions included in our information pack, we used the Arduino and breadboard to set up the circuit. When the circuit was complete, we connected it to the computer with the USB cable. We loaded the ReadAnalogVoltage program into the Arduino.  We were able to see the resistance of the thermistor on the Arduino software. We changed to code to give us a reading every second.



We decided to test the thermistor. We tested it by putting the thermistor in oil at different temperatures. First we put a test tube of oil into a beaker of ice water.We started off at 10 degrees Celsius and went up by 10 degrees Celsius until we reached 70 degrees. We did this by heating the beaker using a Bunsen burner. We put the thermistor in the oil for 30 seconds and recorded the results, we then graphed it.

Temperature  (°C)	Voltage (V)
10	2.25
20	1.86
30	1.62
40	1.28
51	0.92
62	0.63
70	0.47

                                                                                         
                                                                                     

As we increased the temperature of the oil, the voltage decreased. This meant that the resistance of the thermistor increased as the temperature increased. This showed that the circuit and thermistor were working.






We used the software GeoGebra to graph the results.                                                         

24.02.15 - Radio Communications

Testing the Radio

For our Primary Mission we used one radio to send data from the CanSat, and another one to receive data at the laptop. We used the USB converter to connect one radio to the laptop. 

We connected the radio (that sends the data to the computer) pin to the Arduino TX pin. 

Photo credits: Georgina

Testing the Radio

We decided to test the radio. We set up the circuit by connecting the arduino, the breadboard to one of the radios and we plugged in the other radio into our computer. 

Wei Ying and Georgina stood in one spot holding the computer with the radio connected to it, while Aoife and Terri-Ann held the other radio and . We wanted to find the distance between the radios until the connection was lost. 

We did three tests in total.

• Test 1: 0.38km before disconnection 
• Test 2: 0.42km before disconnection
• Test 3: 0.39km before disconnection

18.02.15 - Soldering

As none of us had soldered before, we decided to practice by building a night light.  

 Everyone took turns soldering. 

"This is so fun!"

        

        The kit consisted of:            

• a solar panel
• a circuit board
• a rechargeable battery
• battery holder
• resistors 
• diodes
• an LED light
• wires    

As you can see the night light is working. There is no light received to the solar panel, therefore the LED light turns on. 

The solar panel is taking in light and storing it in the battery. 

03.02.15 - Our First CanSat Meeting

We began reviewing the CanSat Project today.

Our Primary Mission is to measure temperature and pressure, and send this information to a laptop through a radio link. We will need a parachute for the CanSat to land safely after it has been launched. 


For our Secondary Mission we decided to use a CO2 sensor to measure the amount of CO2 in the air.

Top left to right: Georgina Martyn, Terri-Ann Ferguson
Bottom left to right: Wei Ying Chang, Aoife Flannagan