Basics: How Do I Choose Appropriate Sensors?

For a robot to react to its environment, it must first obtain information about its surroundings. Robots are not limited to just sight, sound, touch, smell and taste. Robots can not only sense but give accurate values for a variety of environmental factors that humans are otherwise unaware of or incapable of doing.

 Measure Distance

• Contact (when an object is touched) and Proximity (object is close)
• Ultrasonic Range Finders (variable distances)
• Infrared and laser (used for a specific distance or range)
• Accelerometers (distance based on initial position, integrated twice),
• IMU's (distance based on initial position and includes rotation)
• Encoders and Disks (location based on number of evolutions of the wheel)
• Linear Potentiometer (location along slider)
• Resistive band (location along a band)
• Stretch and Bend Sensors (distance stretched or related)

Measure Rotation

• Potentiometer (usually 0 to 300 degrees)
• Gyroscope (angle based on initial value)
• IMU's (angle based on initial value and includes possible linear acceleration)
• Encoders and Disks (angle based on number of fractional turns)
• Stretch and Bend Sensors (moving closer or farther - use geometry)

Measure Environmental Conditions

• Light Sensor (specific color, intensity or range)
• Sound sensor (specific decibel reading or range)
• Thermal Sensors (specific temperature or temperature range)
• Infrared (used to measure temperature)
• Temperature and Humidity (range of values)
• Cameras and Vision Sensors (measure depth, color, proximity and object type)
• Barometric Sensor (measure pressure)

Measure Orientation and Position

• Compass (orientation with respect to earth’s magnetic field)
• Accelerometers (distance based on initial position, integrated twice),
• IMU's (distance based on initial position and includes rotation)
• Gyroscope (angle based on initial value)
• Stretch and Bend Sensors (orientation of specific parts)
• Localization and GPS (fixed sensors locate an object in 3D space)

Miscellaneous

• Current and Voltage Sensors (range of values)
• Magnetic Sensors (intensity of magnetic field)
• Vibration (specific value or range of values))
• Stretch and Bend Sensors (object warping or changing shape/position)