Explorations in Haptic Feedback: Gentle Alarms with the Adafruit Flora

This week’s workshop looked at vibrations and other means of haptic feedback. For this exercise I wanted to look into haptic vibrations specifically as alarms for quick time naps that can be felt on the body so the user can be nudged out of sleep more gently and less intrusively.

Figure 1. Adafruit flora with sleeping mask.
Figure 1. Adafruit flora with sleeping mask prototype.

I looked into the DVR board and vibration motors online when I stumbled across this DIY tutorial by Becky Stern. She had used the board and motor to create a timely vibrating headband that would vibrate after a certain amount of time has passed. She did this to help her time her meditation sessions.

Figure. 2 Haptic Headband by Becky Stern.
Figure. 2 Haptic Headband by Becky Stern.

Inspired by timely vibrations and familiarizing myself with the different waveforms I started to sketch out some sleeping scenarios where I could attach a vibrating wearable device. This idea was only meant for quick time naps spanning from 10 minutes while taking a break from studying.


Figure 3 and Figure 4. Sketches of sleep mask and blanket.

First picture using a blanket wrap near the shoulder. Second picture using a headband with the flora attached on top.

Figure 5. Adafruit Flora

While spring cleaning I dug out my Adafruit Flora board that I found in my closet. It still worked so I decided to play around with it to test out different waveforms from the Arduino IDE library that worked with the DVR board.

Figure 3. Breadboard setup with the Adafruit Flora
Figure 6. Breadboard setup with the Adafruit Flora.
Figure 7. Testing different vibration sensor waveforms.

After going through all the waveform vibrations I really liked the waveforms of 65 – 70. They were powerful enough yet soft on the skin to be awoken to gently. I went with 65.

Figure 8. Ardunio serial port. Displaying different waveforms.
Figure 9. Timed flora code from Becky Stern’s DIY Haptic Headband. I adjusted the waveform number to 65 and changed the wait variable to 5.

Using the example code I got from Becky’s DIY page, I adjusted the waveform interval in the code and ran it through the Flora. I set the timing for 5 seconds so the vibrating sensor would go off every 5 seconds.

In later iterations I would use conductive thread and sew the flora onto either a blanket or sleep mask with a portable battery set. Perhaps multiple vibration sensors weaved and sandwiched within a blanket or the mask that meet the right spots could mimic the sensation of gentle nudging to help awake one from their sleep.