Experiment 1: Hello Vibe Motors
First, I tested LRA vibrating motor with Arduino sample “Blink” code. I felt the motor vibrating on my fingertips and the back of my hand. I also tried it on my arm and on the table under my arm to feel the different skin sensing. I tried it also on my neck and face. I noticed that there are significant differences in the felt frequency when the motor is mounted on glabrous versus hairy skin. I tried with altering the pace of vibration with long and short delays, and I noticed that the vibration pattern was more recognizable with the slower pace. With short delays, it felt as if the vibration is continuous. Then, I tried testing the LRA vibrating motor with the “Fade” example code. I explored creating a different vibration pattern by modifying the code, so that the motor vibrates on even number counts of its intensity and it’s off on odd number counts while it was fading in and out. I tried it on my fingertips and the back of my hand. it wasn’t easy to notice the intensity changes of vibrations. it required a lot of concentration to be able to recognize the fading in and out pattern.
Experiment 2: Motor Arrays
For this experiment, I used multiple vibration motors in order to experiment with sensations that travel on the skin and the propagation of surface waves between a number of motors. I used 2 motors for this experiments and modified the “fade” example to activate them in sequence. I tried placing them on different locations on my fingers, hands and arms to see if I could sense any haptic illusions. Surprisingly, I was able to feel a vibrating line between two vibrators placed on my pinky finger. I tried to make the two motors to vibrate interchangeably with the modified “fade” code; one that fades with odd number counts, and the other to vibrate with even number counts. It slightly felt like a line was going back and forth between the two vibrating motors placed on my pinky finger.
Experiment 3: Haptic Motor Drivers
For this experiment, we used Adafruit’s haptic motor drivers. I downloaded the Arduino library and tried the “basic” example code that goes through all the driver’s different vibration patterns. I tried also the “complex” example code and played around with different vibration effects to achieve an interesting sequence. I tried randomly many combinations but for me none of the sequences made any specific sense or gave an interesting outcome; they were just trials for different haptic effects.
Haptic Feedback Design Application: Expressive Haptic Throw Blanket
For this workshop, I was interested in Surround Haptics that offer immersive gaming and theater movie experiences.
I propose designing an expressive throw blanket that provides immersive embodied experience in home theater environment through vibro-tactile sensations on the entire body. This haptic blanket is designed to provide smooth tactile motions to intensify emotions and enhance viewers’ movie experiences. The device is meant to be wearable and portable.
I planned to create moving tactile strokes by embedding multiple vibrators on a cozy, flexible, soft, lightweight throw or blanket that is easy to put on, sit on, or wrap your body with, and it’s big enough to fit various body sizes. The vibrators will be equally spaced and arranged in a matrix configuration so that when the blanket is wrapped around the full body, the actuators will be in contact with the full body: the shoulder, back, hip, thigh, knee, shin, back of the legs, upper arm, lower arm, palms of the hand, and stomach. Obviously, vibrations on cloth covered body areas will be less noticeable, so the frequency and power of vibrations should be somehow strong enough to be sensed. The goal is to create illusion of tactile sensation in order to make the movie viewer feel immersed by haptic sense. The haptic effects should flood the user’s entire body.
Flexible haptic throw blanket can be sat on or wrapped with while watching a movie for an enhanced immersive emotional experience.
Coding and Testing Materials:
SparkFun KY-038 Sound Sensor
LRA vibrating motor
Adafruit haptic motor driver
5mm LED – Red
5mm LED – Yellow
5mm LED – Blue
3x 10K ohm resistors
The haptic sensation for this project will be based on the Adafruit haptic motor driver effects, meaning that the vibration pattern is identified by the volume and intensity of perceived sound. Using Arduino code, I programed the device to be synchronized with spatial sounds using a sound sensor. The haptic device will respond to 3 different volume thresholds, and for each threshold a different vibration effect is actuated. For low volume sounds the vibration pattern will be smooth and short, for medium volume sounds the vibration pattern is moderate with medium intensity, and for higher volumes the vibration will get longer and more intense. I also included 3 different colors of LED lights as a visual representation for testing purposes.
It’s my first time to work with Sound detection sensors, and they can be very useful for many ambient environmental designs where sound, lighting and haptics can be all synchronized in real time. I found it challenging to create detailed tactile sensations that reflects movie events. For this project, I used general vibrations or pulses predefined in the Adafruit Motor Driver, however, the haptic feedback pattern is not synchronized with a specific movie narrative or its peak moments.
This prototype can be applied for many other examples other than immersive theatre experiences. It can be interesting if it’s used when listening to music while relaxing on a couch or bed, where you can feel the tones of musical instruments moving along your body. Also it can be very useful for deaf people where they can be notified of door knocking or any other alarming sounds that might occur.
For the future, to design a more sophisticated haptic throw blanket, we can make the haptic effects to feel more realistic by recording tactile signals from the real environment and assigning them to prerecorded sound effects. Then, sound effects can be mapped corresponding to each part of the body so the user feels as if the sounds run through the body. These ideas require more skills and further research in order to be achievable.
Israr, Ali, Seung-Chan Kim, Jan Stec, and Ivan Poupyrev. “Surround Haptics: Tactile Feedback for Immersive Gaming Experiences.”ACM, 2012. doi:10.1145/2212776.2212392.