Computers as an Expressive Medium

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Computers as an Expressive Medium

• Lab 9 Braitenburg Vehicles
• Mayhew Seavey

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Glad you woke up for this?

• Braitenburg vehicles
• Sources to BImage to Sensors to Wheel
• Code Questions

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Sources to BImage

• Our main two objects are Vehicle and Source. The
  Vehicle travels around and its movement depends
  on the readings it gets from the source.
• However, what happens when were within the radii
  (or radiusses) of multiple sources?

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Sources to BImage

• Some blending can occur if the sources reach
  eachother.
• The example code uses a BImage called the ground
  to represent how much light is touching that
  point.

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Sources to BImage

• Instead of calculating how close the vehicles
  sensor is to each source and figuring out how
  much light it sees, we calculate the brightness
  at each point on the screen at the beginning, and
  whenever we move a light.

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Bimage to Sensor

• Then we just look at the pixel information at the
  sensor every time the vehicle needs to move. Both
  sensors are at slightly different locations, so
  they will see different pixels.

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Bimage to Sensor
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Bimage to Sensor
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BImage to Sensor

• What information is our sensor getting?
• It will just give us a number between 0 and 1
  telling us how much light it is seeing. We can
  use this information however wed like.
• The more types of sources we make, the more
  sensory information well need to provide. For
  instance, a pixel could ALSO contain a number
  between 0 and 1 representing how much sound we
  hear. Well discuss more how to do this at the
  end.

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Sensor to Wheel

• What do we do with this number?
• We can use this information to guide our vehicle.
  We do this by changing the speed that one of our
  wheels is turning.
• We can hook our sensors up to the wheels on the
  same side, or those on opposite sides.
• Lets look at an opposite side example.

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Sensor to Wheel
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Sensor to Wheel
Lets make the sensor slow down the wheel its
attached to.
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Sensor to Wheel
Lets make the sensor slow down the wheel its
attached to.
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Sensor to Wheel
Lets make the sensor slow down the wheel its
attached to.
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Sensor to Wheel

• You can model a number of reactive behaviors
  using this simple method. The key thing to
  remember is that by changing the wheel speed on
  different sides of the vehicle, you cause it to
  change speed AND direction.

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Multiple Senses

• Using multiple senses requires some expansion of
  the code.
• First, in order to blend the sensory data of like
  types, but not other types, it will be necessary
  to store a BImage for each type. (one for light,
  one for sound, etc.)
• Well also need to have different types of
  sources. We can either use a field in the class
  designating the source type, or use inheritance.

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Multiple Senses

• If we want to see the Images laid out on top of
  eachother, however, well need to do some work
  with alpha channels.

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Group Coding!!

• Lets try together!