Intro: Squat Sense
With weight loaded on your back, what feels like "below parallel" often isn't. Proper squat execution is lowering your hips past your knees (breaking parallel).
I created Squat Sense as a detector for this break in parallel.
How it works:
By using a push button, the wearer can set the value for his or her desired depth. When the button is pressed, the current bend value is saved to the board. As the the wearer moves, the current bend value is then compared to the set value. The LEDs shine red to green depending on how far away or close, respectively, the wearer is to the target position. The system blinks green and vibrates a motor upon reaching desired depth
- 1 Rehband 7751 Knee Support Sleeve
- 1 Adafruit Flora board
- 4 Adafruit FloraRGB Smart NeoPixels (version 2)
- 1 Bend sensor
- 1 push button
- 1 Vibo meter
- Puffy paint
- Conductive thread
- Regular sewing thread
- Stretch fabric for covering
- Pen and pencil
Code to run
Step 1: Creating the Bend Sensor
To create my sensor, I used the Instructables tutorial Neoprene Bend Sensor
Materials I used:
- Elbow Support Sleeve from Kroger
- Velostat by 3M from LessEMF
- Conductive thread from Adafruit's FLORA budget kit
- Stretch conductive fabric from LessEMF
- Fusible interfacing from Joann's fabric
- Black sewing thread from Joann's fabric
- Flat Iron (CHI hair straightener)
- Sewing needle from Adafruit's FLORA budget kit
- Pencils and markers
For the step that involves fusing the interface on the conductive thread, I temporarily panicked. I thought I had an iron in my house, but was mistaken. True to the "hacker" mentality, I used a flat iron instead. It actually ended up being advantageous because of the size of the strip.
NOTE: To get valid Flora output from the bend sensor, initialize the internal pull-up resistor by simply adding the code: pinMode(9, INPUT_PULLUP).
Step 2: Creating the Push Button
To create the push button, I followed a tutorial from Instructables.
Materials: - Elbow Support Sleeve from Kroger - Conductive thread from Adafruit's FLORA budget kit - Regular sewing thread - Stretch conductive fabric from LessEMF - Fusible interfacing from Joann's fabric - Black sewing thread from Joann's fabric
- Flower stencil from about.com
Tools: - Flat Iron (CHI hair straightener) - Sewing needle from Adafruit's FLORA budget kit - Scissors - Pencils and markers
To make my push button, I used scraps leftover from my bend sensor. I cut out two square of leftover knee sleeve material and cut fingertip-sized holes in the center of each square.
Fuse or sew (with regular thread) conductive fabric to one side of each square.
(Original design was a flower-button, hence "petals")
With regular thread, sew two pieces together, with conductive fabric on the outsides so they don't touch.
Conduct one side to GND and the other side to D12, and you're ready to test!
Step 3: Sewing It Together
The next step is sketching out your designs. Because we are creating wearable that involves a lot of bending, it's important to have clean, simply lines. The less wires have to cross, the better.
I chose having my LEDs displayed in a line, to reduce the amount of wirecrossing/sewing.
NOTE: My first attempt resulted in a burnt knee sleeve because I crossed my wires. (Picture shown).
For this iteration, I sewed the bend sensor to the back of the leg. Ultimately, it requires some playing with to see where on the leg you get the best reading. Initially, I thought the back of the leg produced the best reading, but with the weight of the battery back and all the added components, I think the side of the leg my produce a better reading. So experiment!
With regular thread, sew the bend sensor vertically inside the knee sleeve (dorsal side, so it rests against the back of the knee). With the conductive thread, sew into the conductive fabric ends, connecting one end to D9 and the other end to GND.
With regular thread, attach push button to the knee sleeve. With conductive thread, connect one side of the button to D12 and the other side to GND. NOTE: Be sure not to cross your wires, or the button will not work!
Sew RGBs in sequence along the side of the knee sleeve. For your first RGB, use conductive thread to connect DIN (arrow pointing toward the RGB) to D9. Connect the (+) to VBATT and (-) to GND.
Connect your remaining RGBs. For each additional RGB, sew it's DIN to the preceding RGB's DOUT (arrow pointing away from the RGB). Sew the (+) to the previous RGB's (+) and (-) to the preceding (-).
Apply puffy paint to the inside of the knee sleeve, insulating all wires. Let dry.
Apply puffy paint to the outside of the knee sleeve, insulating all wires. Let dry.
Cover your RGBs (optional) with fabric.
Upload code to board. You're now ready to start squatting!
Step 4: What You Should See
Connect the Flora to power source, the RGBs should blink red. The blinking indicates that the squat angle has not been set. Squat to desired depth, and press the push button. This should cause the RGBs to blink green, indicating that the value has been set. As you stand up, the RGBs should go from green to yellow (and possibly red). Squatting back down should turn the RGBs green, and blink green when you reached your set depth.
NOTE: make sure the bend sensor is not stretched inside the sleeve, this creates too much resistance and gets an inaccurate reading.