Valve timing system for liquid fuel rockets

1. A valve controller comprising:

at least one current sensor input;

at least one voltage sensor input;

a processor and a memory, the processor being connected to the at least one current sensor input and the at least one voltage sensor input, wherein the valve controller is configured to determine at least one actual minimum impulse bit of a valve based on a current profile and a voltage profile of a single valve operation, and wherein the valve controller is configured to adjust valve controls to account for the at least one actual minimum impulse bit.

2. The valve controller of claim 1 , wherein the actual minimum impulse bit is correlated with at least one external factor, and wherein the valve controller is configured to adjust the valve controls to account for the at least one actual minimum impulse bit and the at least one external factor.

3. The valve controller of claim 2 , wherein the external factor is at least one of an engine pressure and battery voltage.

4. The valve controller of claim 1 , wherein the valve controller is configured to determine the at least one actual minimum impulse bit on an initial operation of the valve.

5. The valve controller of claim 1 , wherein the valve controller is further configured to periodically determine an updated minimum impulse bit of the valve.

6. The valve controller of claim 5 , wherein the valve controller is further configured to adjust valve controls based on a most recently determined updated minimum impulse bit of the valve.

7. The valve controller of claim 1 , wherein the minimum impulse bit is based in part on an initial valve opening time, the initial valve opening time being determined to be a dip in a ramp up of the current profile.

8. The valve controller of claim 1 , wherein the minimum impulse bit is based in part on a fully closed valve time, the fully closed valve time being determined to be a time between a voltage spike and a valve control current being driven to zero by the valve controller.

9. The valve controller of claim 8 , wherein the minimum impulse bit is based in part on an initial valve opening time, the initial valve opening time being determined to be a dip in a ramp up of the current profile.

10. The valve controller of claim 1 , wherein each of the at least one current sensor and the at least one voltage sensor are connected to, and configured to sense, a valve control signal line.

11. The valve controller of claim 10 , wherein the valve control signal line is controllably connected to a liquid fuel rocket engine valve.

12. The valve controller of claim 11 , wherein the liquid fuel rocket engine valve at least partially controls a flow of liquid fuel form a fuel repository to a combustor.

13. A method for determining a minimum impulse bit of a valve comprising:

monitoring a current profile and a voltage profile of a valve control signal;

determining an initial valve open time to be a beginning of a dip in a current ramp up and determining a valve fully closed time to be a voltage spike of the valve control signal; and

determining the minimum impulse bit of the valve to be a length of time from the initial valve open time to the valve fully closed time.

14. The method of claim 13 , further comprising correlating the minim impulse bit of the valve with at least one external environmental factor.

15. The method of claim 14 , wherein the at least one external environmental factor includes at least one of an engine pressure and battery voltage.

16. The method of claim 13 , further comprising periodically reiterating the method and updating the determined minimum impulse bit of the valve at each iteration.

17. A liquid fuel rocket engine comprising:

a combustor;

a liquid fuel repository connected to the combustor via a fuel line and a first valve;

an oxidizer repository connected to the combustor via an oxidizer line and a second valve; and

a valve controller configured to output a valve control current to the first valve, the valve controller storing instructions for determining at least one actual minimum impulse bit of a valve based on a current profile and a voltage profile of a single operation of the first valve, and to adjust valve controls to account for the at least one actual minimum impulse bit.

18. The liquid fuel rocket engine of claim 17 , further comprising at least one current sensor configured to sense a current profile of the valve control current and at least one voltage sensor configured to sense a voltage profile of the valve control current.