Keer Zhao
Intro to Physical Computing
fantasy device ideas
To be continued..
basic setup
Power Source:
Arduino Board connect to Mac
Components:
Breadboard, Red LED, 220ohms Resistor, Wires
Descriptions:
Since the yellow bin area is out of Power Jack, I decided to use Arduino 3.3V as a power source. When it's connected, the Red LED emits light.
Wrong setup
Correct setup
*MISTAKE
Power Source:
Arduino Board connect to Mac
Components:
Breadboard, Red LED, 220ohms Resistor, Wires, Pushbutton
Descriptions:
I mistakenly connect the output of the pushbutton and both ends of the LED directly to the ground.
In that case, the potential difference between the LED is ZERO, that's why the LED does not light.
I fix this by having two ends of the LED in two different rows (special thanks to Frank who helped me out : )
Left:
Lighting up three red LEDs at the same time
Right:
Adding a Potentiometer to the circuit.
*Potentiometer is soldered with three wires.
LAB Project #1 - #3
#1
#2
#3
Left:
Three pushbuttons in PARALLEL. Any pushbutton can light up the LED.
Right:
Three pushbuttons in SERIES. The LED will light when all three pushbuttons are pushed.
First time trying with a MOTOR.
'Bad sitting posture alarm'
Goal: To design a device that when people are sitting with bad postures, the red LED will light as an alarm.
Design Mechanism: When people change from a good and bad posture, as their head and neck move, a string will be pulled and trigger a piece of wire completing a circuit.
Basically, this is a device that starts as 'not connected, and then as the neck pulls, the circuit is 'connected'.
I think of having a piece of bare wire, wrapping just a portion of it with tape as the insulated part. A movable part will be a wire bent in a spring shape so that it can slide easily between the insulator and connector.
Ideally, in a good posture, the spring will be at the insulator; in a bad posture, the spring will be pulled to the wire, completing the circuit, the LED lights.
2021.09.19
Stage 1 - Circuit test
On a piece of bare wire, parts of it is wrapped with tape. The LEFT picture shows the initial state that in a good posture, the circuit is incomplete.
The RIGHT picture shows when the wire is pulled, the 'spring' touches the bare wire, conducting the electricity,eventually LED lights.
ISSUE:
1. The wrapped insulator part is extremely not smooth, which then hinders the 'spring' to slide.
2. I do not have a real SPRING. If I can have one, then one end will be anchored, the other side will be pulled.
LEFT picture shows the entire setup. I use my glass to connect the breadboard. In a bad posture, the blue wires will pull the brown string and the 'insulator-connector complex' up (imaging the device is in vertical position), the LED will light.
NEXT STEP:
1. Get rid of the breadboard, replacing the power source with a 9V battery (BUY IT).
2. Find a real SPRING, trying to attach one end to the brown string, the other anchored. This should smooth out the sliding process.
To be continued....