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.
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| 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.
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| 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 1. Failure Attempt
Video 1 shows that the motor was always spin, no matter with room light or flash light.
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.
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| Circuit 1:Batman release |
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| 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.
4.
Provide at least 2 new videos of your setup in action, one being a failed attempt.
Successful Run
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 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.
