Controller Systems

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Controller Systems

• Tufts EMID - Spring 2015

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Typical Controller System
Sensors
Acquisition System (Arduino)
Mapping Software (Max)
Output (Reason)
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Useful Resources

• Fraden, A Handbook of Modern Sensors
• sensorwiki.org
• Datasheets for components

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Parts Sources

• mouser.com
• digikey.com
• sparkfun.com

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What can we sense?

• ON/OFF, momentary or toggle
• Position, velocity, acceration, rotation
• Temperature, light, sound
• Pressure, touch, torque, bending, strain

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Types of Sensors

• Discrete - only can give a value of 0 (off) or 1
  (on)
• Continuous - Resistors or current generators.
  Some can be connected directly to the Arduino.
  Others need buffering, amplification, and/or
  filtering to provide usable data

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Switches

• Discrete output
• Toggle - on or off
• Momentary - on or off when pressed
• Rotary multiple-position
• Can provide visual and tactile feedback

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Potentiometers
Vref

• Common types
• Linear taper
• Audio taper (logarithmic)
• Rotary, linear, multiturn

Vout
GND
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Soft Potentiometers

• Linear
• Circular

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Other Variable Resistors

• Photoresistors
• Bend Sensors
• Force-Sensing Resistors

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Photoresistors/Photocells

• Sense the absence or presence of light
• Change resistance when amount of light changes

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Bend Sensors

• Resistance decreases when bent

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Force-Sensitive Resistors

• Resistance drops when pressed
• Shorthand name FSR

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Variable Resistors
Vref
R1 (variable)

• Vout Vref R2/(R1R2)
• If sensor range 10k to 35k?,
• and R2 20k? then
• Vout range .66Vref to .36Vref

Vout
R2
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Accelerometers

• Measure inclination (direction), acceleration in
  1, 2, or 3 axes

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Distance Sensors

• Infrared
• Ultrasonic

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Piezoelectric Materials

• Sensitive to vibration
• Excellent drum triggers, contact microphones

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Capacitive Sensors

• Detects changes in capacitance, often by
  measuring your body capacitance
• Can detect proximity, distance, location,
  acceleration
• Think Trackpads, Cell/Tablet Screens, Theremin

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Other Sensors

• EMG (Muscle Sensor)
• Joysticks (X and Y axis variable resistors)
• Gesture Recognizers
• Rotary Encoders

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Connecting Sensors

• Using Arduino boards
• Read in digital and analog signals
• Connect via USB and can talk to MAX

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Breadboards

• Simple way to create circuits without soldering

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Reading in Data in MAX

• Using Arduino2MAX

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Putting It All Together
Arduino2MAX