Sensing body heat.

Automotive electronics maker Melexis (Tessenderlo, Belgium) has developed a sensor that uses a unique approach to keeping car occupants comfortable--it takes their temperatures. Unlike current sensors used in automatic climate control systems which measure ambient air temperature, the Melexis MLX90601 sensing module uses an infrared beam that directly measures the body surface temperature of occupants and uses that information to adjust the HVAC output. Melexis' CEO. Rudi de Winter, says that the new sensor costs about the same as traditional sensors but unlike them it does not require ventilation so it takes up less space and gives designers more packaging freedom. It also eliminates the need for a separate solar sensor that many current systems employ to help measure the solar loads on occupants.

The infrared technology is versatile: it can be focused on the windshield to detect temperature differences that would lead to frost or fogging and adjust the climate control system accordingly. It could also be used in conjunction with filters to detect gases like carbon dioxide in the cabin--which will be a necessary safety measure once C[O.sub.2]-based air con units hit the market in large numbers.--KEW