One of the main concerns of the visually challenged person is to locate the surrounding obstacles. A white cane is the primary device that is used to help navigation. However, it would not be the best assistive device in terms of providing information to the user. The aim of the team project is to design a device that could enhance the functionality of the white cane providing more information to the user about his/her surrounding objects. Hot object detection is one of the functionalities of the cane that can be improved. Given the way in which the cane is used, the detection is required to be done in a non-contact fashion. Thus, the principle of absorbing thermal radiation is essential to this project. A thermopile that is a “pile” of thermocouples is used to absorb the objects’ thermal radiations. This will lead into a potential difference proportional to the amount of the energy absorbed. The potential difference across the thermopile is amplified since it is in the order of micro-volts. The obtained signal is then filtered to suppress the contaminating noise coming from various sources such as 60 Hz power line and the instruments. A mathematical relationship between the potential difference and the relative temperature of the object with skin is modelled. Several tests have been conducted to verify the functionality of the design and results are presented.
Akbari, Alireza, "Design of a Hot Object Detector for Smart Mobility Cane" (2009). EE 4BI6 Electrical Engineering Biomedical Capstones. Paper 1.