Application of infrared thermal imaging in rehabilitation engineering: preliminary results

People with severe motor impairments often require an alternative access solution to communicate. We introduce a novel, non-invasive access solution based on infrared thermal imaging. Thermographic videos of ten participants (two with severe disabilities) were recorded with an infrared thermal camera during repeatedly cued mouth opening and closing. An algorithm based on adaptive intensity thresholding, motion tracking and morphological analysis detected mouth opening with high sensitivity and specificity (average sensitivity: 88.5%, average specificity: 99.4%). Our findings suggest that further research on the infrared thermographic access solution is warranted. Infrared thermography can be used as a non-contact and non-invasive access pathway for individuals who retain voluntary mouth opening and closing. Flexible camera location, convenience of use and robustness to ambient lighting levels, changes in background scene and extraneous body movements make this a potential new access modality that can be used night or day in unconstrained environments.