As with all wearable technology projects I’ve worked on, power is one of the big challenges. There are all sorts of really cool things you can make, but as soon as your system requires 12V to run, it becomes unwieldy and not really wearable unless it’s a backpack to start with.
here is a fairly compact 12V battery pack, I found on Amazon, but it still weighs almost a pound. Doable for some applications, but wouldn’t work to wear on the forearm and at $34 each, makes it difficult to have a couple extra on hand
In the past, I have been very pleased with Sparkfun’s 5V rechargeable power bank for both function and affordability. It is compact and light weight, comes with a cord to power your project and recharge the battery. Additionally, the power button on the battery can double as an on/off switch for the entire project.
The big problem with the initial prototype is that the solenoid valves needed 12V to open and close. With a bit of digging and research, I was able to find some 5V solenoids as well as a mini air pump, and ordered some for the next iteration of this project.
For my initial prototype and testing, I was using an Arduino Uno and a Sparkfun RedBoard for the micro controller, however, I’m going to switch to a much smaller ProMicro board now that the code has been tested.
After fusing the nylon with a heat press, but leaving one side open, the small valves were installed, and then the last side sealed.
Test with a hand pump:
This wasn’t quit the dramatic shape change I was hoping for, but not too bad for a first try.
The next step was to hook it up to a system with tubes, an air pump and small solenoid valves.
Even with all the components wired to a bread board, all the components, except for power, for this project fit into a small flat box. Still a bit big to wear on your arm, but a few adjustments and I think it will work.
Functional Code with Buttons
The prototype worked pretty well. The level tracking function worked, and partially inflated the correct pouches.
Power! The current system needs different power sources to run the valves, pump, and microcontroller. Additionally, a 12V battery pack will certainly interfere with the “wearability” of the device.
Shape changing is too subtle. Need to make the pouches bigger, or change the angle of the fused shape in middle of pouches, or separate the pouches and make them individual, or rewrite code so there is more air pressure flowing into each pouch, or some combination of these options.
Material. After running the test code for a while, some of the pouches started to leak and wouldn’t inflate all the way. I’d also like to look into getting plastic fixtures for attaching the pump to the pouches to lower weight and cost.
Working in the “ThingLab” over the summer on a couple different projects involving haptic control interfaces and pneumatics inspired the development of this one.
According to Google, the definition of haptic is: “relating to the sense of touch, in particular relating to the perception and manipulation of objects using the senses of touch and proprioception.” In controlling the many systems we interact with daily, there are situations where visual faculties are occupied, obscured, or permanently impaired so discovery and control are delegated to our hands.
As a first attempt, I thought a simple controller defining levels with up and down selector pads would be useful and have broad application(volume, fan speed, etc…). The outer forearm seemed like a good place to attach it to a human body as there will be minimal interference during activity and can be worn over clothing if needed. A Vambrace in terms of armor.
Here is a first concept sketch of what I’m thinking. Some air-tight pouches hooked up to tubing that connects to a tiny pump and some sensors embedded under the (+) and (-) to act as control buttons.
The basic idea for this project is a skirt that reacts to motion and lights up when you spin around on the dance floor. For social dancing like blues, swing, and salsa, the “show off” moment is when a dancer spins, so I wanted a skirt that only lights up at that time.
The function is accomplished by running a simple program that reads the position in the z-axis of a 3-axis sensor and triggers a light strand to blink if the reading is above a certain value.
Overall, I was pretty happy with the way my first prototype turned out, however, I became immediately aware of a construction problem during the first live trial.
The sensor and, pro micro and LED strips performed great, and as expected, but my solder joints on the LED strips around the hem of the skirt began breaking almost immediately. I did some research into other LED and wire products and found an alternative way to construct my second prototype, which is proving to be much more durable. Here is a link to the Instructable I wrote if you are interested in all the nitty gritty details of this project and a couple demo videos of the second prototype below.
The only issue I have yet to resolve is that the 5V power bank, of which I have tried several, turn off if there is not enough power being drawn off of them, but all you have to do is turn it back on, and everything works fine, so I don’t know if it is even worth addressing. Of the ones I tried out, I think I prefer the Sparkfun version because it has a switch that works to turn it on and off and it has a small digital display that tells you what percentage of charge the battery has left.
Finally got all the info together and organized to post an Instructable for this project if you are interested in recreating your own version. I also entered it into one of Instructables contests, so please like and vote if you enjoy it! Thanks.
First step is to make something integrating a yarn dyed with thermachromic pigment. I decided an ear warmer would be a good platform as the heat wire element might enhance the ear warming function as it heats up to change the yarn color.
I like the way the yarn blends in. Makes for a more dramatic reveal! Now to test it.
Thanks to Laura and Unstable Design Lab for providing the dyed yarn and Wayne for the assist with testing the needed wattage. I’m still unsure of how to actually functionally power this project, but I think it is an interesting idea.
The first prototype we made in class by running wires through a glove and soldering two LEDs on top of the fingers. Making sure that positive wire of both LEDs ran to the tip of each finger, and the negative wires both ran to the thumb. Then when you pinch a coin cell battery it completes the circuit for the finger and thus lights up the light associated with that finger.
Unfortunately, solder isn’t flexible, and after a few times playing with it, the solder joint snapped off one of the LEDs.
I liked this idea and wanted some more experience working with conductive thread that I had only used once before, so decided to make a second version of this glove this time with lights on three of the fingers.
I made sure to stitch a fairly wide pad on each finger to ensure good contact points.
pretty happy with it! Red, White, and Blue.
Had to hook it up to an alternate power source because I ran my battery out of juice.
If I make a third prototype, I would embed a power source in the glove so that you could light it up just by touching each finger to the thumb.
In the final iteration for this idea I decided I wanted the light on the glove to serve a purpose other than just being fun.
Problem: Many apartments do not have a good outside light source near the front door, so during the darker winter months, and for those who work late, it is difficult to find the keyhole in the dark, especially if one is wearing gloves to keep warm.
Idea: Create a glove with an LED that lights up the key hole when the user is holding a key in front of it.
Design Process: I started by taking a pair of gloves I wear all the time with touch pads already embedded in the thumb and forefinger and then used conductive thread to sew a circuit that is completed when the pads are pressed together. This works with or without a key.
While I was sewing the circuit into the glove, I was showing a friend what I was doing, and he commented that he normally holds his keys between his thumb and the middle of his forefinger rather than the tip. So, I made and extra contact pad there by adding some extra stitches with the conductive thread.
This worked quite well!
The light output is quite good and more than sufficient for the intended purpose.