### A Biking Mitten

I recently lost one of my favorite mittens and the remaining mitten was crying out for attention…

Lonely mitten:

My hands get super cold when biking, which is why I used to turn to this pair of mittens to keep my fingers happy. But with one mitten lost and this assignment in mind, I decided to test out an idea of embedding LEDs in the mitten to both act as an extra headlight and to call extra attention to my turn signals. My goal for the sensor was to calibrate it for various lighting modes, including fully lit LEDs with maximum pressure, blinking LEDs with less pressure, and a looping blink pattern when signaling to turn. For this purpose, I decided to make a sensor that could function as both a pressure sensor and a bend sensor (pressure for when you hold the handlebar and bend for when you signal).

Sensor:

Initial sensor testing:

MEASURING RESISTANCE:

Resting: 55-65 kΩ

Active: 1.8 kΩ

CALCULATING VOLTAGE (if internal pull-up resistor is ~35 kΩ):

Resting:

I = V/R

I = 3.6 V/(55 kΩ + 35 kΩ)

I = 0.04 mA

V= I*R

V= (0.04 mA)(35 kΩ)

V = 1.4 mV

Active:

I = V/R

I = 3.6 V/(1.8 kΩ + 35 kΩ)

I = 0.098 mA

V= I*R

V= (0.098 mA)(35 kΩ)

V = 3.4 mV

MEASURED VOLTAGE:

Resting: 0.8-1.0 mV

Active: 1.9-2.2 mV

I integrated the Lilypad into the inside of the top part of the mitten using felt and snaps:

I then sewed in the LEDs following the existing pattern on the top of the mitten:

In process:

Testing the sensor for range of values:

Writing the Arduino code:

Finally, I sewed the sensor into the palm of the mitten:

Mitten in action:

oo