Mass measurement

1. A method comprising:

detecting by a computing device an action that corresponds to a mass-measurement mode; and

in response to detecting the action, causing the computing device to operate in the mass-measurement mode, wherein operating in the mass-measurement mode comprises:

receiving a motion-sensor signal from at least one motion sensor, wherein the motion-sensor signal comprises a first range of frequency components associated with a first range of frequencies and a second range of frequency components associated with a second range of frequencies, wherein the second range of frequencies is higher than the first range of frequencies;

determining a difference between a frequency-component magnitude of at least one given frequency component in the second range of frequency components and a predetermined frequency-component magnitude;

determining a mass of an object based on at least the determined difference between the frequency-component magnitude of the at least one given frequency component from the predetermined frequency-component magnitude; and

causing an output device to provide an indication of the determined mass of the object.

2. The method of claim 1 , wherein the at least one motion sensor is physically coupled to a body part.

3. The method of claim 2 , wherein, when receiving the motion-sensor signal, the mass is physically coupled to the body part.

4. The method of claim 2 , wherein the body part is at least one of a hand, a wrist, an arm, or a head.

5. The method of claim 4 , wherein the body part is the hand, and wherein the at least one motion sensor is contained within one or more of a glove and a ring.

6. The method of claim 4 , wherein the body part is the wrist, and wherein the at least one motion sensor is contained within one or more of a glove and a watch.

7. The method of claim 4 , wherein the motion-sensor signal is a motion-sensor measurement signal, the method further comprising:

before receiving the motion-sensor measurement signal, receiving a motion-sensor calibration signal from the at least one motion sensor, wherein, when receiving the motion-sensor calibration signal, the mass is not physically coupled to the body part; and

determining the predetermined frequency-component magnitude based on the received motion-sensor calibration signal.

8. The method of claim 2 , wherein the motion-sensor signal is a motion-sensor measurement signal, and wherein the mass is a subject mass, the method further comprising:

before receiving the motion-sensor measurement signal, receiving a motion-sensor calibration signal from the at least one motion sensor,

wherein, when receiving the motion-sensor calibration signal, the body part is physically coupled to a calibration mass, and

wherein, when receiving the motion-sensor measurement signal, the body part is not physically coupled to the calibration mass; and

determining a predetermined decrease in frequency-component magnitude associated with the calibration mass based on the received motion-sensor calibration signal.

9. The method of claim 1 , wherein the at least one motion sensor comprises a first at least one motion sensor and a second at least one motion sensor, wherein the first at least one motion sensor is physically coupled to one of a left hand and a right hand, and wherein the second at least one motion sensor is physically coupled to the other of the left hand and the right hand.

10. The method of claim 9 , wherein receiving the motion-sensor signal from the at least one motion sensor comprises:

receiving a first motion-sensor signal from the first at least one motion sensor; and

after receiving the first motion-sensor signal, receiving a second motion-sensor signal from the second at least one motion sensor.

11. The method of claim 1 , wherein the frequency-component magnitude is an average frequency-component magnitude.

12. The method of claim 1 , wherein the at least one motion sensor comprises at least one of an accelerometer or a gyroscope.

13. A system comprising:

a non-transitory computer readable medium; and

program instructions stored on the non-transitory computer readable medium and executable by at least one processor to cause a computing device to:

detect an action that corresponds to a mass-measurement mode; and

in response to detecting the action, cause the computing device to operate in the mass-measurement mode, wherein operating in the mass-measurement mode comprises:

receiving a motion-sensor signal from at least one motion sensor, wherein the motion-sensor signal comprises a first range of frequency components associated with a first range of frequencies and a second range of frequency components associated with a second range of frequencies, wherein the second range of frequencies is higher than the first range of frequencies;

determining a difference between a frequency-component magnitude of at least one given frequency component in the second range of frequency components and a predetermined frequency-component magnitude;

determining a mass of an object based on at least the determined difference between the frequency-component magnitude of the at least one given frequency component from the predetermined frequency-component magnitude; and

causing an output device to provide an indication of the determined mass of the object.

14. The system of claim 13 , wherein the at least one motion sensor is physically coupled to a body part.

15. The system of claim 14 , wherein the motion-sensor signal is a motion-sensor measurement signal, the system further comprising program instructions stored on the non-transitory computer readable medium and executable by at least one processor to cause the computing device to:

before receiving the motion-sensor measurement signal, receive a motion-sensor calibration signal from the at least one motion sensor, wherein, when receiving the motion-sensor calibration signal, the mass is not physically coupled to the body part; and

determine the predetermined frequency-component magnitude based on the received motion-sensor calibration signal.

16. The system of claim 14 , wherein the motion-sensor signal is a motion-sensor measurement signal, and wherein the mass is a subject mass, the system further comprising program instructions stored on the non-transitory computer readable medium and executable by at least one processor to cause the computing device to:

before receiving the motion-sensor measurement signal, receive a motion-sensor calibration signal from the at least one motion sensor,

wherein, when receiving the motion-sensor calibration signal, the body part is physically coupled to a calibration mass, and

wherein, when receiving the motion-sensor measurement signal, the body part is not physically coupled to the calibration mass; and

determine a predetermined decrease in frequency-component magnitude associated with the calibration mass based on the received motion-sensor calibration signal.

17. A non-transitory computer readable medium having instructions stored thereon, the instructions comprising:

instructions for detecting by a computing device an action that corresponds to a mass-measurement mode; and

instructions for, in response to detecting the action, causing the computing device to operate in the mass-measurement mode, wherein operating in the mass-measurement mode comprises:

receiving a motion-sensor signal from at least one motion sensor, wherein the motion-sensor signal comprises a first range of frequency components associated with a first range of frequencies and a second range of frequency components associated with a second range of frequencies, wherein the second range of frequencies is higher than the first range of frequencies;

determining a difference between a frequency-component magnitude of at least one given frequency component in the second range of frequency components and a predetermined frequency-component magnitude;

determining a mass of an object based on at least the determined difference between the frequency-component magnitude of the at least one given frequency component from the predetermined frequency-component magnitude; and

causing an output device to provide an indication of the determined mass of the object.

18. The non-transitory computer readable medium of claim 17 , wherein the at least one motion sensor is physically coupled to a body part.

19. The non-transitory computer readable medium of claim 18 , wherein the motion-sensor signal is a motion-sensor measurement signal, the instructions further comprising:

instructions for, before receiving the motion-sensor measurement signal, receiving a motion-sensor calibration signal from the at least one motion sensor, wherein, when receiving the motion-sensor calibration signal, the mass is not physically coupled to the body part; and

instructions for determining the predetermined frequency-component magnitude based on the received motion-sensor calibration signal.

20. The non-transitory computer readable medium of claim 18 , wherein the motion-sensor signal is a motion-sensor measurement signal, and wherein the mass is a subject mass, the instructions further comprising:

instructions for, before receiving the motion-sensor measurement signal, receiving a motion-sensor calibration signal from the at least one motion sensor,

wherein, when receiving the motion-sensor calibration signal, the body part is physically coupled to a calibration mass, and

wherein, when receiving the motion-sensor measurement signal, the body part is not physically coupled to the calibration mass; and

instructions for determining a predetermined decrease in frequency-component magnitude associated with the calibration mass based on the received motion-sensor calibration signal.