Group Experiments 1 through 3

Group members: Antonio Guimaraes and Noah Pivnick.

Experiment 1 introduced us to the ERM haptics motor with a breadboard and Arduino. Our motor was soldered to male pins which we connected to a small breadboard. We connected pin 13 on the Arduino to power the motor, and ran a wire from the cathode of the motor to ground on the Arduino. 

Arduino Leonardo on the left, power and ground jumper cables connected to mini breadboard on the right, small button vibe motor with short leads soldered to header pins on the breadboard.

Arduino Leonardo on the left, mini breadboard with button vibe motor on the right, close up of Noah's hand holding button vibe motor between thumb and pointer finger.

We noticed the following when taping the motor to our board and touching the board to different parts of the body:

Antonio holding mini breadboard with button vibe motor to back of hand.

Antonio holding mini breadboard with button vibe motor to inner forearm, closeup.

Touching a finger to the board gives a strong sense of haptic vibration.

Touching the breadboard to the back of the hand gives a lighter vibration feeling, but still a pretty significant one.

Touching the breadboard to the lower part of the forearm give a similar sensation to the back of the hand.

Touching the motor to the bak of the earlobe produces a strong sense of vibration. Noah feels like it gives a less sharp sensation, because of fatty tissue and no bone in the earlobe.

If you need to feel something for sure, the earlobe would be a great place to put it. And the motor remains inconspicuous to others.

Using the Arduino blink sketch to activate the haptics motor, we tested the difference in a vibration lasting 50 ms. and one lasting 200 ms. We made the vibrations 2 seconds apart.

We made the following observations:

At 200 ms. felt pretty strong vibrations in the tip of the finger.

At 50 ms. felt more subtle, Antonio says more tolerable, vibrations.

placing the motor to the back of the proximal phalange of the middle finger produced a feeling similar to the intensity from that of tip of finger, at 50 ms

Still at 50 ms. we applied some pressure to the motor with the tip of the finger. The pressure made the vibrations undetectable at this rate. We could feel the vibrations when applying pressure and changing the vibrations to 300 ms.

We also noted a tingling sensation a few seconds after letting go of the motor at 300 ms.

Experiment 2

This experiment made use of the haptic motor driver, with chip DRV2065L.

We had a chip soldered to a haptics ERM motor, the same one we used for experiment 1.

Arduino Uno at top of frame, power, ground, and two signal jumper cables wired to mini breadboard toward bottom of frame, Adafruit DRV2605L Haptic Motor Controller on mini breadboard.

We connected the chip to the breadboard, and wired it properly, then ran a sketch that ran quickly through about 120 different haptic vibrations. These pulsed, hummed, clicked, and were each supposed to give a distinct feeling from the motor. However, after cycling through 123 different options of vibration, we could not differentiate between many of them, because the code moved through them very quickly.

Running through these presets did not feel very satisfying. We were not able to get results we wanted, or to find something very useful from the presets, and that we feel we could apply right away.

Maybe the sensations would be more distinguishable if the motor were loose from the chip and breadboard, and placed in the hand. At any rate, we feel the interval between each vibration in this example could be increased, so we could tell where one vibration ended, and the next one started.

Experiment 3

In this experiment, we worked with 3 of the same haptics motors as before. We taped 3 of them on the table from top to bottom, ran them through the breadboard, connecting them to pins 1, 2, and 3 on the Arduino.

Arduino Uno in upper left corner of frame, power, ground, and three output jumper cables to long breadboard in center of frame, three button vibe motors approximately 1.5 inches apart taped to the surface of the table on the right side of the frame.

We modified the blink sketch to create a pattern with these 3 motors. 

The pattern is to vibrate motor 1 and 3 together, then motor 2 alone. 

We noticed a phenomenon called sensory funnel when two motors in close proximity vibrated against the forearm. Sensory funnel is when two vibrating motors in some proximity to one another against the skin feel like they are in the same location, or feel like just one vibrating motor.