Infrared Radar
Improving upon typical ultrasonic systems, which are ineffective when used around sound-absorbing materials like padded furniture, the Infrared Radar uses infrared light to create a radar rangefinder. Additionally, this radar works faster than ultrasonic radars and improves object identification by measuring the range as well as reflectivity of the target. The speed and single-cycle execution of the ATmega8 microcontroller eliminate the need for external components.
Link: http://www.circuitcellar.com/avr2004/DA3736.html
Improving upon typical ultrasonic systems, which are ineffective when used around sound-absorbing materials like padded furniture, the Infrared Radar uses infrared light to create a radar rangefinder. Additionally, this radar works faster than ultrasonic radars and improves object identification by measuring the range as well as reflectivity of the target. The speed and single-cycle execution of the ATmega8 microcontroller eliminate the need for external components.
Link: http://www.circuitcellar.com/avr2004/DA3736.html