Correlated hemodynamic measurements
Wearable devices are described herein including at least two sensors configured to detect hemodynamic properties of a wearer. A first sensor is configured to detect a hemodynamic property of a portion of vasculature, where the operation of the first sensor is based on a hemodynamic property detected by a second sensor. A timing of operation, a value of one or more controlled operational parameters, a filter setting, or some other aspect of the operation of the first sensor could be controlled based on the hemodynamic property detected by the second sensor. Hemodynamic properties could include blood flow rate, volume, and/or pressure in one or more portions of vasculature, a timing, rate, delay, or other information about heartbeats, an oxygenation level of blood, a velocity of blood cells in blood, or some other information about a wearer's blood, heart, and/or cardiovascular system.
1. A wearable device, comprising:
a first sensor, wherein the first sensor is configured to detect a first hemodynamic property of a first portion of subsurface vasculature of a wearer of the wearable device, wherein the first sensor comprises a filter;
a second sensor configured to detect a second hemodynamic property of a second portion of subsurface vasculature of the wearer of the wearable device, wherein the first portion of subsurface vasculature and the second portion of subsurface vasculature are part of the same blood vessel, wherein the second sensor is a different type of sensor than the first sensor;
a mount configured to mount the first sensor and the second sensor to an external body surface of the wearer such that the first sensor is proximate to the first portion of subsurface vasculature; and
a controller operably coupled to the first and second sensors, wherein the controller comprises a computing device programmed to perform operations comprising:
detecting, using the second sensor, the second hemodynamic property relating to the wearer;
determining, based on the detected second hemodynamic property, a filter parameter for the filter of the first sensor;
detecting, using the first sensor, the first hemodynamic property relating to the first portion of subsurface vasculature, wherein using the first sensor to detect the first hemodynamic property of the first portion of subsurface vasculature comprises operating the first sensor with the filter configured according to the determined filter parameter; and
providing an output indicative of the detected first hemodynamic property.
2. The wearable device of claim 1 , wherein the first and second portions of subsurface vasculature overlap, and wherein the mount is further configured to mount the second sensor to the external body surface proximate to the first portion of subsurface vasculature.
3. The wearable device of claim 1 , wherein providing an output indicative of the detected first hemodynamic property comprises transmitting data indicative of the first hemodynamic property to a server.
4. The wearable device of claim 1 , wherein at least one of the first sensor or second sensor comprises a Doppler ultrasonography probe.
5. The wearable device of claim 1 , wherein at least one of the first sensor or second sensor comprises a tonometer.
6. The wearable device of claim 1 , wherein at least one of the first sensor or second sensor comprises a photoplethysmographic sensor.
7. The wearable device of claim 1 , wherein at least one of the first sensor or second sensor comprises a dynamic laser speckle sensor.
8. The wearable device of claim 1 , wherein the filter parameter controls a frequency response of the filter.
9. The wearable device of claim 1 , wherein the filter parameter selects the filter from a set of filters.
10. The wearable device of claim 1 , wherein the filter comprises a bandpass filter.
11. The wearable device of claim 10 , wherein the filter parameter comprises at least one of a cutoff frequency, a center frequency, or a bandwidth of the bandpass filter.
12. A method, comprising:
mounting a wearable device to an external body surface of a wearer, wherein the wearable device comprises:
a first sensor, wherein the first sensor is configured to detect a first hemodynamic property of a first portion of subsurface vasculature of the wearer, wherein the first sensor comprises a filter;
a second sensor configured to detect a second hemodynamic property of a second portion of subsurface vasculature of the wearer, wherein the first portion of subsurface vasculature and the second portion of subsurface vasculature are part of the same blood vessel, wherein the second sensor is a different type of sensor than the first sensor;
a mount configured to mount the first sensor and the second sensor to the external body surface such that the first sensor is proximate to the first portion of subsurface vasculature; and
a controller operably coupled to the first and second sensors, wherein the controller comprises a computing device;
operating, by the controller, the second sensor to detect the second hemodynamic property relating to the wearer;
determining, by the controller based on the detected second hemodynamic property, a filter parameter for the filter of the first sensor;
operating, by the controller, the first sensor with the filter configured according to the determined filter parameter to detect the first hemodynamic property relating to the first portion of subsurface vasculature; and
providing an output indicative of the detected first hemodynamic property.
13. The method of claim 12 , wherein the first and second portions of subsurface vasculature overlap, and wherein the mount is further configured to mount the second sensor to the external body surface proximate to the first portion of subsurface vasculature.
14. The method of claim 12 , wherein providing an output indicative of the detected first hemodynamic property comprises transmitting data indicative of the first hemodynamic property to a server.
15. The method of claim 12 , wherein the filter parameter controls a frequency response of the filter.
16. The method of claim 12 , wherein the filter parameter selects the filter from a set of filters.
17. The method of claim 12 , wherein the filter comprises a bandpass filter.
18. The method of claim 17 , wherein the filter parameter comprises at least one of a cutoff frequency, a center frequency, or a bandwidth of the bandpass filter.