Agricultural seed sensing and control system

1. An agricultural machine comprising:

a material distribution system comprising a material distribution line configured to convey particulate material to a component; and

a sensing system comprising:

a first sensor configured to generate a first sensor signal indicative of a measure of a flow of the particulate material in the material distribution line;

a second sensor configured to generate a second sensor signal indicative of a measure of the flow of the particulate material in the material distribution line; and

a correlation generation component configured to receive indications of the first and second sensor signals and to generate a correlation metric that represents a correlation between the first and second sensor signals.

2. The agricultural machine of claim 1 , wherein

the material distribution line comprises a first material distribution line configured to convey a first flow of particulate material to a first component;

the material distribution system comprises a second material distribution line configured to convey a second flow of particulate material to a second component; and

the sensing system comprises:

a third sensor configured to generate a third sensor signal indicative of a measure of the second flow of the particulate material in the second material distribution line; and

a correlation application component configured to determine a rate of the second flow based on applying the correlation metric to the third sensor signal.

3. The agricultural machine of claim 2 , wherein the first sensor and the third sensor have substantially similar sensing precision.

4. The agricultural machine of claim 3 , wherein the second sensor has a higher sensing precision compared to the third sensor.

5. The agricultural machine of claim 4 , wherein

the third sensor has a maximum seed sensing rate less than approximately one hundred seeds per second, and

the second sensor has a maximum seed sensing rate that is at least four times higher than the maximum seed sensing rate of the third sensor.

6. The agricultural machine of claim 4 , wherein

the third sensor has an error rate above ten percent for material flow rates above fifty particles per second, and

the determined rate of the second flow is greater than fifty particles per second with an error rate at or less than approximately ten percent.

7. The agricultural machine of claim 6 , wherein the determined rate of the second flow is greater than two hundred particles per second.

8. The agricultural machine of claim 2 , further comprising:

a control component configured to generate a control signal that controls the agricultural machine based on the determined rate.

9. The agricultural machine of claim 8 , wherein the control signal controls a metering system configured to meter the particulate material into the second material distribution line.

10. The agricultural machine of claim 1 , wherein

the particulate material comprises seeds,

the component comprising a row unit configured to disburse the seeds onto a terrain, and

the material distribution system comprising an air source providing an air stream to pneumatically convey the seeds along the material distribution line to the row unit.

11. The agricultural machine of claim 1 , wherein the second sensor has a higher sensing precision compared to the first sensor.

12. The agricultural machine of claim 11 , wherein the second sensor has a maximum sensing rate that is at least four times greater than a maximum sensing rate of the first sensor.

13. The agricultural machine of claim 1 , wherein

the correlation metric comprises a first correlation metric;

the material distribution line comprises a first material distribution line configured to convey a first flow of particulate material to a first component;

the material distribution system comprises:

a second material distribution line configured to convey a second flow of particulate material to a second component; and

the sensing system comprises:

a third sensor configured to generate a third sensor signal indicative of a measure of the second flow; and

a fourth sensor configured to generate a fourth sensor signal indicative of a measure of the second flow; and

the correlation generation component is configured to:

generate a second correlation metric that represents a correlation between the third sensor signal and the fourth sensor signal; and

generate a rate offset metric based on the first and second correlation metrics.

14. The agricultural machine of claim 13 , wherein

the material distribution system comprises:

a primary distribution line that receives particulate material from a metering system; and

a splitter component configured to split the particulate material from the primary distribution line into the first material distribution line and the second material distribution line;

a third material distribution line configured to convey a third flow of particulate material to a third distribution end point component;

the sensing system comprises:

a fifth sensor configured to generate a fifth sensor signal indicative of a measure of the third flow; and

a correlation application component configured to determine a rate of the third flow by applying the rate offset metric to the fifth sensor signal.

15. A method performed by an agricultural machine, the method comprising:

receiving a first sensor signal from a first sensor that senses a first flow of particulate material along a first material distribution line;

receiving a second sensor signal from a second sensor that senses the first flow of particulate material along the first material distribution line;

generating a correlation metric that represents a correlation between the first sensor signal and the second sensor signal;

receiving a third sensor signal from a third sensor that senses a second flow of particulate material along a second material distribution line;

determining a rate of the second flow by applying the correlation metric to the third sensor signal; and

generating a control signal that controls the agricultural machine based on the determined rate.

16. The method of claim 15 , wherein

the particulate material comprises seeds;

the first material distribution line conveys the first flow of seeds to a first row unit;

the second material distribution line conveys the second flow of seeds to a second row unit;

the first and third seed sensors comprise low precision sensors; and

the second seed sensor comprises a high precision sensor.

17. An agricultural machine comprising:

a distribution system comprising:

a first distribution line configured to convey a first seed flow to a first component; and

a second distribution line configured to convey a second seed flow to a second component;

a metering system configured to meter seeds into the first and second distribution lines;

a seed sensing system comprising:

a first seed sensor configured to generate a first sensor signal indicative of the first seed flow;

a second seed sensor configured to generate a second sensor signal indicative of the first seed flow;

a correlation generation component configured to receive indications of the first and second sensor signals and generate a correlation metric that represents a correlation between the first sensor signal and the second sensor signal;

a third seed sensor configured to generate a third sensor signal indicative of the second seed flow; and

a correlation application component configured to determine a rate of the second seed flow based on applying the correlation metric to the third sensor signal; and

a control system configured to generate a control signal that controls the agricultural machine based on the determined rate.

18. The agricultural machine of claim 17 , wherein

the first and third seed sensors have maximum seed sensing rates less than approximately one hundred seeds per second, and

the second seed sensor has a maximum seed sensing rate that is at least four times higher than the maximum seed sensing rate of the first seed sensor.

19. The agricultural machine of claim 18 , wherein

each of the first and second components comprise a row unit configured to disburse the seed onto a terrain, and

the material distribution system comprises an air source providing air streams to pneumatically convey seeds along the first and second distribution lines to the row units.