Physiological measurement system with motion sensing
Embodiments provide physiological measurement systems, devices and methods for continuous health and fitness monitoring. A wearable strap may detect reflected light from a user's skin, where data corresponding to the reflected light is used to automatically and continually determine a heart rate of the user. The wearable strap may include a motion sensor that is used to determine a motion status of the user. Based upon the motion status of the user, the system may activate light emitters on the wearable strap to determine the heart rate of the user.
1. A wearable physiological measurement system, comprising:
a light source including a plurality of light emitters for emitting light of two or more different wavelengths toward a user's skin;
a plurality of light detectors for receiving light reflected from the user's skin;
a motion sensor for detecting a motion of the user; and
a processing module configured to:
determine a motion status of the user that indicates a level of motion of the user based on data received from the motion sensor, and
based on the motion status of the user, automatically and selectively activate one or more of the plurality of light emitters to determine a heart rate of the user, wherein the processing module adjusts the light source to a different wavelength of the two or more different wavelengths based on the motion status.
2. The wearable physiological measurement system of claim 1 , wherein the processing module is further configured to:
upon determining that the motion status indicates that the user is in motion, selectively activate a first set of one or more light emitters and at least one of the plurality of light detectors to perform optical measurement of a pulse rate at the user's skin; and
upon determining that the motion status indicates that the user is at rest or is asleep, selectively activate a second set of one or more light emitters and at least one of the plurality of light detectors to perform optical measurement of the pulse rate at the user's skin,
wherein the second set of one or more light emitters emits light at a longer wavelength than the first set of one or more light emitters.
3. The wearable physiological measurement system of claim 1 , further comprising:
a piezo-sensor for detecting a pulse rate at the user's skin.
4. The wearable physiological measurement system of claim 3 , wherein the processing module is further configured to:
upon determining that the motion status indicates that the user is in motion, selectively activate at least one of the plurality of light emitters and at least one of the plurality of light detectors to perform optical measurement of the pulse rate at the user's skin; and
upon determining that the motion status indicates that the user is at rest or is asleep, selectively activate the piezo-sensor to detect the pulse rate at the user's skin.
5. The wearable physiological measurement system of claim 1 , wherein the processing module is configured to:
upon determining that the motion status indicates that the user is at a first level of motion, activate a first set of one or more light emitters and one or more light detectors to perform optical measurement of a pulse rate at the user's skin; and
upon determining that the motion status indicates that the user is at a second lower level of motion, activate a second set of one or more light emitters and one or more light detectors to perform optical measurement of the pulse rate at the user's skin;
wherein the second set of one or more light emitters emits light at a longer wavelength than the first set of one or more light emitters.
6. The wearable physiological measurement system of claim 5 , wherein the first level of motion is exercise, and wherein the second level of motion is sleep or rest.
7. The wearable physiological measurement system of claim 5 , wherein the second level of motion is sleep or rest.
8. The wearable physiological measurement system of claim 1 , wherein the processing module is configured to:
based on the motion status of the user, automatically adjust power consumption by the one or more of the plurality of light emitters by adjusting a current supplied to the one or more of the plurality of light emitters.
9. The wearable physiological measurement system of claim 1 , wherein the processing module is configured to:
determine a characteristic of reflected light detected at one or more of the plurality of light detectors; and
based on the characteristic of the reflect light, automatically adjust a current supplied to the one or more of the plurality of light emitters.
10. The wearable physiological measurement system of claim 9 , wherein the characteristic of the reflected light indicates an ambient light condition and/or an optical characteristic of the user's skin.
11. The wearable physiological measurement system of claim 1 , further comprising a wireless transmitter, and wherein the processing module is further configured to:
determine an amount of data to be transmitted to an external computational device; and
based on the amount of data to be transmitted, automatically adjust a data transmission rate from the wearable physiological measurement system to the external computational device.
12. The wearable physiological measurement system of claim 11 , wherein the amount of data to be transmitted is based on an amount of data collected by the system from a time when data was last transmitted from the wearable physiological measurement system.
13. The wearable physiological measurement system of claim 11 , wherein physiological data associated with the user is transmitted from the wearable physiological measurement system to the external computational device when the amount of data to be transmitted exceeds a predetermined threshold.
14. The wearable physiological measurement system of claim 1 , further comprising a wireless receiver and a wireless transmitter, and wherein the processing module is further configured to:
use the wireless receiver to detect an external computational device in proximity to the wearable physiological measurement system; and
automatically initiate transmission of physiological data associated with the user from the wearable physiological measurement system to the external computational device using the wireless transmitter.