Lesson 10 - 03/01/2012
The Ball is AllLast week each group presented at least five ideas for an interaction based on a ball. This week: reductions and progress.
Dina Rubanovitch Even-Paz, Omer Ben-Naim, David KantorRipple Table
The first group demonstrates how a sensor registers the ball striking the surface and a camera registers the ball's location, and in reaction a colorful ripple spreads over the computer screen. A piezoelectric sensor responds to the strike of the ball by means of a crystal that causes a change in voltage in reaction to the mechanical force exerted on it. Several questions are raised concerning the system's calibration and how a number of balls will behave together. The next stage of developing the interaction will be to connect all the components of the system (screen, camera, sensor, computer, working environment) in order to solve problems.
The idea of the ball that collects evidence from its surroundings is demonstrated by means of a cell-phone installed inside a plastic ball. The phone transmits images that are projected onto the wall as the ball is rolled around the space by the onlookers. The demonstration highlights that the interaction needs additional directions of thought. The quality of the images that can be transmitted does not enable capturing sharp and legible images.
Dana Mik, Doron Segal, Geva Rosenthal, Aviad FuxLive Balls
The group has refined the features of the Pet Balls it presented last week:
Fleeing Ball - a ball that rolls around independently. When it is picked up, the motor installed inside the ball speeds up and vibrates to convey distress. When placed back on the floor, the ball sounds a giggle and resumes rolling around.
Petting Ball - part of the ball is covered in fur, and stroking it makes it purr with pleasure.
Teaser Ball - a ball that tries to attract attention by sounding a voice that says, "Take ME! ME! ME-ME!", but when it's picked up the ball starts crying, "Why ME? Why ME?"
Pressure Ball - when the ball is picked up, a countdown begins. At the end of the countdown, there's a surprising and unexpected effect.
Pain Ball - a ball that looks as though it's meant for bouncing, but when it's actually bounced, it emits sounds of pain.Roni Rosen, Shahar Yaacoby, Shmulik Mauda
Bouncing SurfaceA surface in which a piezoelectric sensor is installed and connected by means of a Phidgets controller to a Max program, and which plays drumming sounds that change in accordance with the bouncing rhythm. In the critique we discuss the type of sound created and whether it fits in with the sound of the ball bouncing on the surface, and with the whole scenario of using the interaction.
Ball-less BallAn accelerometer sensor is attached to the user's shoe, whose movements are decoded by a program to sonically express the bouncing of an imaginary ball on his foot and kicking it into the goal. The questions raised following the demonstration are about the choice of sensor and its location on the user's body. We also try to think of ways to prolong the interaction by adding elements of achievement to the game.
Jenny Bahar, Osher Shukrun, Itay Kurgan, Shay Merci Timid Balloons
Helium balloons connected to a motor that are drawn toward the user in a rapid movement in reaction to a loud sound. The interaction is highly amusing and makes many of us want to take part by clapping our hands or shouting. The questions raised are about the positioning of the interaction in the space, how multiple balloons will be controlled, and how to ensure continuity.
Hot Air BalloonImages of the landscape from a hot air balloon are projected onto the floor and change in reaction to the weight the user puts into the basket. The weight is measured by means of a Phidgets sensor. The discussion revolves around the type of image that will be projected, and the possibilities of controlling it and the user's physical environment.
After the demonstrations and critiques, Shachar presents a brief overview of different types of electric motors and their features. The lecture begins with general background about magnets and continues with different types of motors:
- Direct Current Motor (DC): the simplest motor to operate. When connected to a power source it rotates in one direction, a reverse connection rotates it in the opposite direction, and the voltage level affects its rotation speed. DC motors are common and inexpensive, but not very precise. - Servomotor: a motor comprising location/position control and usually rotates 180 degrees, i.e., half a full circle. These motors are more powerful and precise, but also more expensive.- Stepper Motor: a motor that can divide a full rotation into a large number of small steps, so the desired direction and number of steps can be determined. The disadvantage is that the motor does not keep track of the number of steps actually performed, making an additional mechanism necessary.- Alternating Current Motor (AC): a more powerful motor connected to power like that in the wall. These motors are of a much higher voltage and consequently more dangerous.- Brushless Motor: a highly resilient, fast, and precise motor, but which requires expensive electronic circuits.
Next WeekNext week will be the intermediate submission of the ball exercise, and each group will present all their interactions in operational and ready-to-experience condition. Museum visitors will help each group choose the interaction with which they will continue until the end of the course. True reality!
Until next time...
Photographs by Aviad FuxWritten by David Kantor
- Lesson 1
- Lesson 2
- Lesson 3
- Lesson 4
- Lesson 5
- Lesson 6
- Lesson 7
- Lesson 8
- Lesson 9
- Lesson 10
- Lesson 11
- Lesson 12
- Final Lesson