For lab1, I create a fold swith using the conductive fabric to control the ON and OFF of an LED. Instead using the thread to sew the conductive and nonconductive fabric together, I use the conductive copper tape to stick one on the top of another.
I tested the resistance of the fabric, it is super conductive on the top surface.
For lab2, I use the fabric to create a force-touch sensor ring. I want to see the if there could difference if I were to press it on different areas on the ring. And I am basicly reading the votage value from the Arduino pins.
But it turns out that the values are the same everywhere, it is only depended on how much force you pressed it. I know this method before, but this is the first time I try it. I think it is pretty robust. It is a great way to build a soft FSR.
I also think about the potential possiblities of this method, one way is to make it a part of a cushion. Kate has already that in class. I was thinking use this methed to make a smart cushion that detect how long you have been sitting. I know the advanced cars use a lot of FSR in the driver’s sit. But this way is easy and cheap to achieve. If you have been sitting for a long time, the cushion would warn you by some actions, like using the vibration motor or something else.
For the fnal project, I want to mimic what Jacquard does. After reading their paper, I find out the way to achieve it is not that hard. But of course, their algorithm is better. At this point, what I can do is to achieve the basic idea of Jacquard, swiping to control something.
I know they detect the capacity of the yarns to get the position of the finger. I can do that.
List of tools:
A good way to remove the fiber
I need to remove the fiber parts of the yarns to expose the inside copper. I tried to burn it with fire, but the result is super disgusting. I also tried to remove the fiber manually, but it very detailed and consumed me a lot of time. Eventually, I came up with a better way. Use the laser! The laser can eat the fiber, while the copper inside would refect the laser back. So there is no way to cut or ruin the copper part, the fiber parts will be removed after rastering it on both side.
I can also use alligator to clip on the fabric directly, but the capcity is not changing significantly.
Then I use the alligators to clip on bunches of copper yarns, the other sides are connected to Arduino pins.
Then connect the LED to the Arduino as the output.
I made 2 examples, one is to do the direction swipe, and then control three LEDs’ ON and OFF. The other one is to use the direction swipe to control the brightnesss of a single LED.
Here is a video documentation.
Things still need to improve:
There are still several things I need to overcome at this point.
The capacity sensing can be affected by many factors, such as the length of the wire; the lay out of the wire, I have to say each time the value is not exactly the same.
The ground. If I disconnect the charger of my laptop, the value can be huge different. The capacity is the value between two objects. The value is always better when one side is grounded.
If I’m addding more wires, the readings are reacting very slow.
Still needs to optimize the algorithm.