Summer Blog 2

This week I continued working with the bend sensor. I made a few more bend sensors trying make them as neat as possible to ensure that the connection flows all the way through. For one of the sensors, I also tried adding a few extra stitches of conductive thread. I have three codes that I have been using to test my bend sensors to determine whether or not they are functioning properly: a basic code that reads an analog input and outputs an LED light, a code that I found online to test bend sensors, and an example code in the Arduino library for a button. I use the button code because if I have two bend sensors that have a solid flowing connection all the way through, then if I connect the analog pin clip to one end of one sensor, and the ground clip to one end of the other bend sensor, and when I touch the two unclipped ends of the two bend sensors together, then it should function as a button. Unfortunately, I still cannot get my bend sensors to work with any of the three codes and I wasn’t exactly sure is the problem was with my sensors or if it had something to do with the code.


When I hit an absolute dead end for making bend sensors, I tried to making a, in a sense, deconstructed bend sensor. I did this in two forms inspired by some forums that I read online. Velostat is a conductive material that decreases in resistance as pressure is applied to it. So, knowing this, I figured that if I tape conductive thread to both sides of a strip of velostat and leave some thread hanging off the end for alligator clips, then it should function as a bend sensor. However, after I made it and connected it to the flora, it was outputting the same values as the bend sensors I made. Then I figure, the problem might be because the not all the thread was touching the surface of the velostat, so I modified the deconstructed bend sensor. I did this by using two full strips of scotch tape, copper strips, conductive thread, and velostat. First I laid two long strips of thead onto the sticky side of both strips of tape, being sure that I taped them down in a way so that when they are laid on top of each other the thread crosses. Then I laid two slightly thinner than the tape strips of velostat in between the conductive thread and then taped the copper tape to each end of the conductive thread. This is essentially the exact same as the bend sensor I am creating. This bend sensor also outputted the same values as the other sensors I made.


Also, for one of my bend sensors, I wanted to see if there was a connection flowing throughout so I attached a power alligator clip to one end and the ground alligator clip to the other end. Then I figured if I touched one end of to the other then it should spark or something when the ends touch because the negative and positives cross and short circuit. When I did this, there was a spark so I knew there was a connection flowing thoughout the sensor, but for some reason it isn’t outputting values that correlate to the bend.


After all these tests, I think that the problem lies in the code but I am not sure what the problem is. The bend sensor should work with a normal analog read to input values. The code that I used that reads an analog input works fine when attached to a light sensor, but doesn’t work when I attach the analog pin to the bend sensor.


Hopefully I can figure out what the issue is when I meet with Katie this week.