Material discrimination by heat flow sensing

We propose a heat flow sensing device with a heat source to discriminate a contact object. The device was a three-layered structure separated by 600 mum-thick PDMS (Polydimethylsiloxane) spacer, and consisted of a micro heater and three resistance-temperature detectors (RTD). We detected transient heat flow with pulse-heating method when 10 mm-cubic blocks of cork, acrylic and aluminum were on contact with the device. Temperature gradient induced by heat flow differed by materials of contact objects. We also evaluated the surface temperature from two RTDs. Our device identified relative difference in thermal effusivity of materials.