From this reading both the heart beat and constriction of the blood vessel can be determined. Nonetheless, the wires felt like they were in the way. We are interested in moving them off the hands to sense what people are feeling during certain consumer tasks such as diapering an infant. This is a particularly challenging task as it is important not to drag the wires through the dirty diaper, or let the infant grab them and pull them, or put them in his mouth. In other words, we are investigating options for moving the sensors off the hands.
Respiration is the easiest sensor to wear and is the most immune from motion artifacts.
It uses a constrained Hall effect sensor to measure the expansion and contraction of the chest cavity. We have been investigating the optimal placement for the EMG sensor to detect stress. The greatest challenge of EMG placement is to find a muscle to which the EMG electrode pad will stick well and which is not involved in muscle motion. To solve the problem of affixing the sensors we are currently considering the use of new electrodes and glue designed by the Boston University Neuro-muscular Research Center which have been demonstrated to stay affixed through rigorous physical activity. Small self-contained sensor systems such as this allow affective information to be wirelessly transmitted to a larger computer for analysis.