Project Description:

Temperature is an important data source for weather forecasting, agriculture irrigation, anomaly detection, etc. While temperature measurement can be achieved via low-cost yet standalone hardware with reasonable accuracy, integrating thermal sensing into ubiquitous computing devices is highly non-trivial due to the design requirement for specific heat isolation and proper device layout. We present the first integrated thermometer using commercial-off-the-shelf acoustic-enabled devices. Our Software Sonic Thermometer (SST) utilizes on-board dual microphones on commodity mobile devices to estimate sound speed, which has a known relation with temperature. To precisely measure temperature via sound speed, we propose a chirp mixing approach to circumvent low sampling rates on commodity hardware and design a pipeline of signal processing blocks to handle channel distortions. SST, for the first time, empowers ubiquitous computing devices with thermal sensing capability. It is portable and cost-effective, making it competitive with current thermometers using dedicated hardware. SST is potential to facilitate many interesting applications such as large-scale distributed thermal sensing, yielding high temporal/spatial resolutions with unimaginable low costs. Our SST prototype on a commodity platform achieves a median accuracy of 0.5 centigrade even at varying humidity levels.

Acknowledgement:

• This project is accomplished when I was a Ph.D student at Huazhong University of Science and Technology.

  People:

  • Dr. Chao Cai (Electronic Information & Engineering) - HUST
  • Henglin Pu (UG student, Electronic Information & Engineering) - HUST
  • Yan Yan (Master student, Electronic Information & Engineering) - HUST
  • Dr. Rong Zheng (Professor, Software Computing & Engineering) - Mcmaster University
  • Dr. Jun Luo (Associate Professor, Computer Science & Engineering) - Nanyang Technological University

  Related Publications:

• [1] C. Cai, H. Pu, M. Hu, R. Zheng, and J. Luo, "SST: Software Sonic Thermometer on Acoustic-enabled IoT Devices," in IEEE Transactions on Mobile Computing, 2020
• [2] H. Pu, C. Cai, M. Hu, and R. Zheng. Non-contact thermal sensing on acoustic-enabled IoT devices. In ACM UbiComp/ISWC ’19 Adjunct.