Tuesday, April 19, 2016

Week 14

Blog sheet Week 14:
This week’s blog sheet will be as group.
Your blogsheet 14 tasks:
1.      Video of your RG group setup.

video
Video 1. Explanation of group set up

       

      Group set up:
       Matt’s RG will be the starter of the whole class and it will end up with light on the LED. The LED light’s signal will be Yao’s set up’s trigger, after the LED on, Yao’s motor will start to spin and then drag two magnets to each other. The attractive force between two magnets will become the trigger for the next group. That’s how our RG set ups connected.





Figure 1. Yao's circuit

Figure 2. Track of motor

Figure 3. Matthew's circuit

2.     Video of your RG group in action

a.     Failed attempt


video
Video 2. Failure Attempt

      Batman should go down after the flash light signal, but it failed.


b.     Successful attempt


video
Video 3. Successful Attempt

The successful attempt shows how the project should run.

Thursday, April 14, 2016

Week 13

Blog sheet Week 13:

This week’s blog sheet will be both individual and group.

Yao:
Your blogsheet 13 tasks:
1.     Provide the updated computer drawing for your individual RG setup.
Figure 1. Circuit Design of Yao's Rube Goldberg set up

2.     Explain your setup (Red font means new added).


As figure 1 shows, I used Opamp, half-rectifier, photocell, transistors, relay, and motor in my Rube Goldberg design. The photocell will be the trigger for the whole design.
Matthew's RG design will end up with light on the LED, and then the light from his LED will trigger my RG design: the photocell's resistor value will decrease with the LED light.
The first part of my RG design is an Oscillator (Opamp), which can give us square wave output, and it can work as AC signals source. 
Then the second part makes up by half- rectifier, two 3.3kΩ resistors, and photocell. Half rectifier can convert AC signal to DC signal, and then two resistors work as voltage divider. When there is room light, the photocell has high resistance, and because the photocell is parallel with the 3.3kΩ resistor, then the output of second part will be high-level (voltage divider theory); When there is flash light, the photocell has low resistance, and the output will be low-level.
The third part will be R7 and the transistor Q1, the output of second part will be the input of the third part. If the input signal of the third part is high-level (which means room light condition), then the transistor will become on-state, which means the output will low-level; If the input signal of the third part is low-level (which means flash light condition), then the transistor will become off-state, which means the output will high-level. The output of the third part will connect to the second transistor Q2.
The second transistor Q2 works similarly to the first transistor Q1: If the input signal of the Q2 is high-level, then the transistor will become on-state, which means the output will be low-level; If the input signal of the third part is low-level, then the transistor will become off-state, which means the output will be high-level. The output of Q2 will connect to Relay’s Pin 2.

Relay works as switch here. Pin 1 will connect to the voltage source +9V, and it will be the amount of voltage sent to Pin 3 or Pin4; Pin 2 will connect to the output of transistor Q2; Pin 3 will connect to the motor; Pin 5 will also connect to +9V. If transistor Q2’s output is low-level, Pin 3 will work, and then the motor will spin (Pin 4 is not used here).
           After the motor spinning, the motor will drag a magnet close to another other magnet, and there will be a force resistor between two magnets, then the force between two magnets would make the force resistors' value decrease, and it will be the trigger for the next group. 

3.     Provide photos of the circuit and setup.


Figure 2. Rube Goldberg set up
Figure 2 shows the circuits and the set up of the Rube Goldberg and the magnet set up.

4.     Provide at least 2 new videos of your setup in action, one being a failed attempt.


video
Video 1. Failure Attempt

Video 1 shows that the motor was always spin, no matter with room light or flash light.

video
Video 2. Successful Attempt 


Video 2 shows the Rube Goldberg set up worked successfully.

5.     What failures did you have? How did you overcome them?


On Wednesday’s class, the motor of my RG set up was always spinning no matter room light or flash light. I checked the relay first, and I found the relay’s “click” sound when I turn on the power supply and when I turn it off, which it not supposes to be like that (the relay should have click sound if I give the photocell a flash light signal). Then I checked the output of oscillator part with oscilloscope, and it was working perfectly, then I checked the output of half-rectifier, and I found I found the oscilloscope shows negative value which is not suppose to be like that. I changed a new half-rectifier and then the who set up worked properly.


On Friday’s class, the same problem happened again, the motor was always spinning (That’s also what we showed in the video 3). I checked the outputs of the oscillator and half-rectifier, and they were both right. Then I checked all the connections, and then finally I found the second transistor had bad connection with the breadboard. After the transistor connecting to the breadboard, the whole set up runs well.


Matthew:
Your blogsheet 13 tasks:
1.     Provide the updated computer drawing for your individual RG setup. 

Circuit 1:Batman release
Circuit 2


2.     Explain your setup.


There will be one bread board with a photocell on it, when I shine the bat light on the photo cell the motor will turn. When the motor turns it will pull the release for batman to come to the rescue. When Batman hits the switch, the switch will turn on the hair dryer. The hair dryer will heat the temp sensor. Once the temp sensor is warm it will engage a relay. Once the relay is engaged it will turn on the LED light strip activating Yao’s photocell.



3.     Provide photos of the circuit and setup.
Circuit 1
Circuit 2

Improved mount
Improved mount with weight


4.     Provide at least 2 new videos of your setup in action, one being a failed attempt.
video
Successful Run

video
Failed Run

5.     What failures did you have? How did you overcome them?
One failure that I had was with my circuit 1. My relay was not making a good connection, this did not allow my motor with spin, thus stopping my whole circuit. All I had to do to overcome this issue was to make sure that my relay was making a good connection with the bread board. 
II also had an issue with the mount for my motor. I couldn't get my motor mount to stay on its side, and if if it was not on its side the motor would not pull the rip cord for Batman. So to over come this I added another side to the mount, and added some weight to it to hold it in place. As seen in the photos above. 




6.     Group task: Explain your group RG setup.


      Matt’s RG will be the starter of the whole class and it will end up with light on the LED. The LED light’s signal will be Yao’s set up’s trigger, after the LED on, Yao’s motor will start to spin and then drag two magnets to each other. The attractive force between two magnets will become the trigger for the next group. That’s how our RG set ups connected.


7.     Group task: Video of a test run of your group RG.


video
Video 3. The failure Attempt of Group RG

      This is a failure test since Yao's motor was always spinning, but the motor should spin only after the LED on.