System and method for vibration severity measurement

1. A sensor device for rotating machinery, the sensor device comprising:

an enclosure forming a sealed cavity;

an attachment piece to rigidly secure the enclosure to the rotating machinery; and

an electronics assembly secured within the sealed cavity of the enclosure, the electronics assembly comprising:

a vibration sensor,

a wireless communications interface for exchanging data with a user device, and

a general-purpose processor configured to:

receive a measurement request from the user device,

configure a working range for the vibration sensor based on a first data sample and in response to the measurement request, wherein configuring the working range includes calibrating the vibration sensor with a higher resolution for smaller vibration amplitudes or calibrating the vibration sensor with a lower resolution for larger vibration amplitudes,

receive, from the vibration sensor, additional data samples for multiple axes,

calculate a component velocity root mean square (vRMS) value, from the additional data samples, for each of the multiple axes, wherein the calculating minimizes processor cycles of the general-purpose processor, and wherein the calculating comprises:

identifying a first axis sample from the additional data samples for the multiple axes, wherein the first axis sample includes an acceleration time domain (TD) value,

converting the acceleration TD value to an acceleration power spectrum density (PSD) value,

converting the acceleration PSD value to a velocity PSD value, and

converting the velocity PSD value to one of the component vRMS values,

combine the component vRMS values into a sample vRMS value,

send a final vRMS value, based on the sample vRMS value, to the user device via the wireless communications interface, and

generate an alert signal when the final vRMS value exceeds a threshold; and

a disposable battery that powers the vibration sensor, the wireless communications interface, and the general-purpose processor.

2. The sensor device of claim 1 , wherein, when configuring the working range for the vibration sensor, the general-purpose processor is further configured to:

collect the first data sample of vibration data from the vibration sensor, and

determine the working range for the vibration sensor based on a maximum value and a minimum value of the first data sample of the vibration data.

3. The sensor device of claim 1 , wherein the general-purpose processor is further configured to:

automatically initiate a sleep state for the sensor device after the sending.

4. The sensor device of claim 1 , wherein the general-purpose processor is further configured to:

generate multiple sample vRMS values, including the sample vRMS value, from different component vRMS values, and

average the multiple sample vRMS values into the final vRMS value.

5. The sensor device of claim 1 , wherein the sensor device is configured to attach to the rotating machinery as a single piece.

6. The sensor device of claim 1 , wherein the vibration sensor includes a Micro-Electromechanical System (MEMS) accelerometer.

7. The sensor device of claim 1 , wherein, when converting the acceleration TD value to an acceleration PSD value, the general-purpose processor is further configured to:

convert the acceleration TD value to an acceleration frequency domain (FD) value,

square the acceleration FD value, and

normalize the squared acceleration FD value to a frequency bin width that corresponds to the working range.

8. The sensor device of claim 1 , wherein the wireless communications interface includes an interface for a wireless personal area network (WPAN).

9. The sensor device of claim 1 , wherein, when sending the final vRMS value, the general-purpose processor is further configured to:

transmit a unique identifier associated with the rotating machinery.

10. A method, comprising:

receiving, by a general-purpose processor in a sensor device, a measurement request,

wherein the measurement request is provided from a user device via a wireless communication interface, and

wherein the sensor device includes an enclosure forming a sealed cavity, an attachment piece to rigidly secure the enclosure to a machine, and an electronics assembly, within the sealed cavity, that includes the general-purpose processor, a vibration sensor, the wireless communication interface, and a disposable battery that powers the electronics assembly;

configuring, by the general-purpose processor and in response to the measurement request, a working range for the vibration sensor in the sensor device, based on a first data sample, wherein configuring the working range includes calibrating the vibration sensor with a higher resolution for smaller vibration amplitudes or calibrating the vibration sensor with a lower resolution for larger vibration amplitudes;

receiving, by the general-purpose processor and from the vibration sensor, additional data samples for multiple axes;

calculating, by the general-purpose processor, a component velocity root mean square (vRMS) value, from the additional data samples, for each of the multiple axes, wherein the calculating minimizes processor cycles of the general-purpose processor, and wherein the calculating comprises:

identifying a first axis sample from the additional data samples for the multiple axes, wherein the first axis sample includes an acceleration time domain (TD) value,

converting the acceleration TD value to an acceleration power spectrum density (PSD) value,

converting the acceleration PSD value to a velocity PSD value, and

converting the velocity PSD value to one of the component vRMS values,

combining, by the general-purpose processor, the component vRMS values into a sample vRMS value;

generating, by the general-purpose processor, an alert signal when the final vRMS value exceeds a threshold; and

sending, by the general-purpose processor, a final vRMS value, based on the sample vRMS value, to the user device via the wireless communication interface.

11. The method of claim 10 , wherein combining the component vRMS values includes performing vector addition to combine an x-axis component value, a y-axis component value, and a z-axis component value of the component vRMS values.

12. The method of claim 10 , wherein configuring the working range for the vibration sensor comprises:

collecting the first data sample of vibration data from the vibration sensor, and

determining the working range for the vibration sensor based on a maximum value and a minimum value of the first data sample of the vibration data.

13. The method of claim 10 , further comprising:

automatically initiating, by the general-purpose processor, a sleep state for the sensor device after the sending.

14. The method of claim 10 , further comprising:

generating multiple sample vRMS values, including the sample vRMS value, from different component vRMS values, and

averaging the multiple sample vRMS values into the final vRMS value.

15. The method of claim 10 , wherein the vibration sensor includes a Micro-Electromechanical System (MEMS) accelerometer.

16. The method of claim 10 , wherein converting the acceleration TD value to an acceleration PSD value includes:

converting the acceleration TD value to an acceleration frequency domain (FD) value,

squaring the acceleration FD value, and

normalizing the squared acceleration FD value to a frequency bin width that corresponds to the working range.

17. A system for monitoring rotating machinery, the system comprising:

a sensor device including:

an attachment piece to rigidly secure an enclosure to the rotating machinery,

a vibration sensor,

a first wireless communications interface for exchanging data with a user device, and

a first general-purpose processor configured to:

receive a measurement request from the user device,

configure a working range for the vibration sensor based on a first data sample and in response to the measurement request, wherein configuring the working range includes calibrating the vibration sensor with a higher resolution for smaller vibration amplitudes or calibrating the vibration sensor with a lower resolution for larger vibration amplitudes,

receive, from the vibration sensor, additional data samples for multiple axes,

calculate a component velocity root mean square (vRMS) value, from the additional data samples, for each of the multiple axes, wherein the calculating minimizes processor cycles of the general-purpose processor, and wherein the calculating comprises:

identifying a first axis sample from the additional data samples for the multiple axes, wherein the first axis sample includes an acceleration time domain (TD) value,

converting the acceleration TD value to an acceleration power spectrum density (PSD) value,

converting the acceleration PSD value to a velocity PSD value,

converting the velocity PSD value to one of the component vRMS values, and

generating an alert signal when the final vRMS value exceeds a threshold,

combine the component vRMS values into a sample vRMS value, and

send a final vRMS value, based on the sample vRMS value, to the user device via the wireless communications interface,

a disposable battery that powers the vibration sensor, the first wireless communications interface, and the first general-purpose processor, and

the enclosure, the enclosure forming a sealed cavity over the disposable battery, the first wireless communications interface, and the first general-purpose processor.

18. The system of claim 17 , further comprising:

the user device including:

a second wireless communications interface for exchanging data with the sensor device;

a memory to store instructions; and

a second processor configured to execute the instructions to:

establish a communication session with the sensor device,

send a measurement request to the sensor device,

receive, from the sensor device, the final vRMS value, and

present, to a user, the final vRMS value.

19. The system of claim 18 , further comprising:

a network device configured to:

receive, from the user device, the final vRMS value, and

store the final vRMS value associated with other data for the rotating machinery.

20. The system of claim 17 , wherein the first general-purpose processor is further configured to:

generate multiple sample vRMS values, including the sample vRMS value, from different component vRMS values, and

average the multiple sample vRMS values into the final vRMS value.