Attitude insensitive flow device system and method
View Patent ↗Disclosed herein are systems and methods for attitude insensitive flow devices. The system can include a flow device having a processor and a computer readable medium accessible by the processor that stores a set of computer instructions executable by the processor. The computer instructions can include instructions executable to receive an orientation signal, receive a sensed flow signal, and determine a flow through the flow device based on the sensed flow signal and the orientation signal.
1. A flow device comprising:
a fluid inlet;
a fluid outlet;
a flow sensor, in fluid communication with the fluid inlet and the fluid outlet, to sense a flow rate of a fluid through the flow sensor and provide a flow signal indicative of the sensed flow rate of the fluid through the flow sensor;
an orientation sensor to provide an orientation signal indicative of an orientation of the flow sensor relative to a reference direction; and
a processor configured to receive the flow signal and the orientation signal and determine a corrected flow rate of the fluid through the flow sensor based upon the flow signal and the orientation signal.
2. The flow device of claim 1 , wherein the orientation sensor is capable of identifying at least four distinct orientations of the flow sensor relative to the reference direction.
3. The flow device of claim 2 , further comprising:
a memory, coupled to the processor, to store a plurality of offsets, each offset corresponding to a different orientation of the at least four distinct orientations of the flow sensor relative to the reference direction.
4. The flow device of claim 3 , wherein the processor is configured to select an offset from the plurality of offsets based upon the orientation signal, and adjust the flow signal based upon the selected offset to determine the corrected flow rate of the fluid.
5. The flow device of claim 3 , further comprising:
a memory, coupled to the processor, to store a plurality of offsets, each offset corresponding to a particular type of fluid and a different orientation of the at least four distinct orientations of the flow sensor relative to the reference direction.
6. The flow device of claim 5 , wherein the processor is configured to select an offset from the plurality of offsets based upon the orientation signal and the particular type of fluid, and adjust the flow signal based upon the selected offset to determine the corrected flow rate of the fluid.
7. The flow device of claim 6 , wherein the processor is further configured to select the offset after the flow device is powered up.
8. The flow device of claim 3 , further comprising:
a memory, coupled to the processor, to store a plurality of offsets, each offset corresponding to a different orientation of the at least four distinct orientations of the flow sensor relative to the reference direction, a particular type of fluid, and a pressure upstream of the flow device.
9. The flow device of claim 8 , wherein the processor is configured to select an offset from the plurality of offsets based upon the orientation signal, the particular type of fluid, and the pressure upstream of the flow device, and adjust the flow signal based upon the selected offset to determine the corrected flow rate of the fluid.
10. The flow device of claim 9 , wherein the processor is further configured to select the offset after the flow device is powered up.
11. The flow device of claim 3 , further comprising:
a memory, coupled to the processor, to store a plurality of offsets, each offset corresponding to a different orientation of the at least four distinct orientations of the flow sensor relative to the reference direction and a density of a particular type of fluid.
12. The flow device of claim 11 , wherein the processor is configured to select an offset from the plurality of offsets based upon the orientation signal and the density of the particular type of fluid, and adjust the flow signal based upon the selected offset to determine the corrected flow rate of the fluid.
13. The flow device of claim 1 , wherein the flow device includes a printed circuit board, and wherein the processor and the orientation sensor are disposed on the printed circuit board.
14. The flow device of claim 1 , wherein the flow device is a mass flow controller, the flow device further comprising:
a valve, disposed between the fluid inlet and the fluid outlet and in fluid communication with the flow sensor;
wherein the processor is further configured to receive a setpoint indicative of a desired flow rate of the fluid to be provided by the fluid outlet, compare the setpoint to an indicated flow rate of the fluid being provided by the fluid outlet, and provide a valve drive signal to the valve based upon a difference between the setpoint and the indicated flow rate.
15. The flow device of claim 14 , wherein the indicated flow rate is based upon the flow signal and the valve drive signal is based upon the difference between the setpoint and the indicated flow rate and upon the orientation signal.
16. The flow device of claim 15 , wherein the orientation signal is determined after the flow device is powered up.
17. The flow device of claim 14 , wherein the indicated fluid flow rate is based upon the corrected flow rate.
18. The flow device of claim 17 , wherein the processor is further configured to receive the flow signal and the orientation signal, to filter the flow signal, and to determine the corrected flow rate of the fluid through the flow sensor based upon the filtered flow signal and the orientation signal.
19. The flow device of claim 18 , wherein the processor is further configured to compare the sensed flow rate of the fluid through the flow sensor to a plurality of gas flow curves to generate a fitted flow signal, filter the fitted flow signal, and generate the indicated flow rate based upon the filtered fitted flow signal and the orientation signal.
20. The flow device of claim 19 , wherein the orientation signal is determined after the flow device is powered up.