Smart sweat stimulation and sensing devices
The disclosed invention provides sweat sensing devices with smart sweat stimulation and sensing embodiments: which improve the dependability and predictability of sweat sampling rates; achieve a desired number of sweat sampling events per day while minimizing skin irritation and prolonging device lifespan; and use physical, optical or thermal sweat stimulation to augment or replace chemical sweat stimulation.
1. A method of measuring at least one analyte in sweat with a sweat sensing device, comprising:
applying a sweat sensing device to a wearer's skin;
scheduling a plurality of sweat sampling events that are required for an application;
measuring a sweat generation rate from the wearer's skin;
determining a sweat onset temperature;
stimulating sweat if the sweat generation rate is insufficient to provide each of the plurality of sweat sampling events with a sweat sample having a chronological assurance; and
taking a plurality of sweat analyte readings.
2. The method of claim 1 , wherein sweat generation rate is determined by one of the following measurements: GSR, skin impedance, skin conductivity, and concentration of at least one sweat ion.
3. The method of claim 1 , further comprising: measuring the wearer's skin temperature and comparing the temperature to a sweat onset temperature prior to stimulating sweat.
4. The method of claim 3 , further comprising: stimulating sweat if the wearer's skin temperature is proximate to the sweat onset temperature prior to a time at which a sweat sampling event is scheduled to occur, and sweat generation rate is insufficient.
5. The method of claim 3 , further comprising: instructing the wearer to increase skin temperature if the wearer's skin temperature is not proximate to the sweat onset temperature prior to a time at which a sweat sampling event is scheduled to occur, and there is sufficient time for the wearer to raise the skin temperature proximate to or greater than the sweat onset temperature.
6. The method of claim 3 , further comprising: stimulating sweat if the wearer's skin temperature is not proximate to the sweat onset temperature prior to a time at which a sweat sampling event is scheduled to occur, and there is insufficient time for the wearer to raise the skin temperature proximate to or greater than the sweat onset temperature, and sweat generation rate is insufficient.
7. The method of claim 3 , further comprising: instructing the wearer to decrease skin temperature if the wearer's sweat generation rate is in excess of the sweat generation rate needed to provide a sweat sample for a scheduled sweat sampling event.
8. The method of claim 1 , further comprising adjusting sweat stimulation, at least in part, upon a previous response to sweat stimulation by the wearer.