1. A fuel metering system, comprising:
a fuel metering valve coupled to receive valve position commands and operable, in response thereto, to move to a valve position, the fuel metering valve having a position control characteristic that is represented by an N-th order polynomial equation;
a valve characteristic circuit mounted at least proximate the fuel metering valve, the valve characteristic circuit including a plurality of resistors, each resistor having a resistance value representative of at least one digit in the N-th order polynomial equation;
a controller coupled to the valve characteristic circuit, the controller operable to:
(i) selectively determine the resistance value of each resistor,
(ii) determine the fuel metering valve position control characteristic using the determined resistance values, and
(iii) selectively supply the valve position commands to the fuel metering valve using the determined fuel metering valve position control characteristic.
2. The system of claim 1, wherein:
the valve characteristic circuit further includes a multiplexer disposed between the controller and at least a portion of the resistors, the multiplexer operable, in response to channel select signals, to selectively couple one of the plurality of resistors to the controller; and
the controller is further operable to selectively supply the channel select signals to the multiplexer.
3. The system of claim 1, wherein the controller is configured to determine the resistance value of a resistor by:
supplying an excitation current to the resistor to thereby generate a voltage drop across the resistor; and
measuring the voltage drop across the resistor.
4. The system of claim 3, wherein the excitation current has a predetermined current magnitude.
5. The system of claim 4, wherein the predetermined current magnitude is about 1.0 milliamps.
6. The system of claim 1, wherein the position control characteristic is a flow versus valve position characteristic.
7. The system of claim 1, wherein:
the N-th order polynomial equation includes N-number of coefficients;
each resistance value represents a digit in a decade of one of the N-number of multi-decade coefficients.
8. The system of claim 1, further comprising:
a position sensor operably coupled to the fuel metering valve for sensing a position of the fuel metering valve and supplying a fuel metering valve position signal representative thereof,
wherein the controller is coupled to receive the fuel metering valve position signal and is further operable to selectively supply the valve position commands based at least in part thereon.
9. The system of claim 1, further comprising:
a fuel supply line having an inlet adapted to receive a flow of fuel, and an outlet adapted to supply fuel to a turbine engine combustor,
wherein the fuel metering valve is disposed in flow series in the fuel supply line to thereby control fuel flow through the fuel supply line.
10. The system of claim 9, further comprising:
a flow sensor operably coupled to the fuel supply line for sensing flow rate of the fuel through the fuel supply line and supplying a flow signal representative thereof,
wherein the controller is coupled to receive the flow signal and is further operable to selectively supply the valve position commands based at least in part thereon.
11. A valve assembly having a position control characteristic that is represented by an N-th order polynomial equation, the valve assembly comprising:
a valve housing having at least a fluid inlet, a fluid outlet, an a flow passage between the fluid inlet and fluid outlet;
a valve element mounted on the valve housing and disposed at least partially within the valve housing flow passage, the valve element movable between a closed position and an open position; and
a valve characteristic circuit mounted on the valve housing, the valve characteristic circuit including a plurality of resistors, each resistor having a resistance value representative of at least one digit in the N-th order polynomial equation.
12. The valve of claim 11, wherein the valve characteristic circuit further includes:
a multiplexer having a supplysense terminal, a plurality of resistor terminals, and a plurality of channel select terminals, the supplysense terminal adapted to receive an excitation current, each of the resistor terminals coupled to one of the resistors, and the channel select terminals adapted to receive channel select signals, the multiplexer operable, in response to the channel select signals, to selectively couple one of the resistors to the supplysense terminal.
13. The valve assembly of claim 11, further comprising:
a valve actuator coupled to the valve element and adapted to receive valve position commands, the valve actuator responsive to the valve position commands to move the valve element between the open and the closed positions.
14. The valve assembly of claim 11, wherein the position control characteristic is a flow versus valve position characteristic.
15. The valve assembly of claim 11, wherein:
the N-th order polynomial equation includes N-number of coefficients;
each resistance value represents a digit in a decade of one of the N-number of multi-decade coefficients.
16. A method of supplying flow calibration data for a valve assembly, comprising the steps of:
measuring flow versus valve position data for the valve;
determining an N-th order polynomial curve fit equation from the measured flow versus position data, the N-th order polynomial curve fit equation including N-number of coefficients;
determining resistance values to represent at least one digit in each of the N-number of coefficients; and
mounting a plurality of resistors at least adjacent to the valve assembly, each resistor having a resistance value equal to one of the determined resistance values.
17. The method of claim 16, further comprising:
selectively determining the resistance values of each of the plurality of resistors;
generating the N-th order polynomial curve fit equation using the determined resistance values; and
controlling valve position using the N-th order polynomial curve fit equation to obtain a desired flow through the valve assembly.
18. The method of claim 17, wherein the step of selectively determining the resistance values of each of the plurality of resistors comprises:
selectively supplying an excitation current of a predetermined current magnitude to each resistor to thereby selectively generate a voltage drop across each resistor; and
measuring the voltage drop across each resistor.
19. The method of claim 18, wherein the predetermined current magnitude is about 1.0 milliamps.
20. The method of claim 16, wherein:
the N-th order polynomial equation includes N-number of coefficients;
each resistance value represents a digit in a decade of one of the N-number of coefficients.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of installing computer programs in a network having a set of computers comprising the steps of:
providing a first installation computer having operating software and installation software;
providing a set of at least one client computer broadcasting installation requests at a dynamically adjustable rate; in which a client computer initially broadcasts installation requests at an initial request rate and monitors the total installation request rate carried on said network, wherein said installation requests include requests for operating system software; and said client computer adjusts its own broadcast rate by comparing said total installation request rate with a target installation request rate and adjusting its own rate by an adjustment amount that depends on the difference between said total installation request rate and said target request rate;
said first installing computer responds to a first installation request and installs both said operating software and installation software on a first client computer of said set of computers, thereby establishing said client computer as a secondary installation computer, and during which installation operation, said first installing computer ignores installation requests;
upon completion of the first installation, both said first installing computer and said secondary installation computer service installation requests by installing both said operating software and installation software.
2. A method of installing computer programs in a network according to claim 1, in which said adjustment amount is linearly proportional to said difference between said total installation request rate and said target request rate.
3. A method of installing computer programs in a network according to claim 1, in which said target rate is proportional to the total network bandwidth rate.
4. A method of installing computer programs in a network according to claim 3, in which said target rate is less than 10% of the total network bandwidth rate.
5. A method of installing computer programs in a network according to claim 1, in which an installing computer responds to an installation request received by it in a probabilistic manner.
6. A method of installing computer programs in a network according to claim 5, in which an installing computer responds to a first installation request received by it according to an initial reference probability.
7. A method of installing computer programs in a network a client computer according to claim 6, in which an installing computer responds to an installation request received by it according to a current installation probability and, upon completing an installation request responded to by it reduces its current installation probability by a reduction factor to calculate a new current installation probability with which it will respond to future requests.
8. A method of installing computer programs in a network according to claim 7, in which said installing computer transmits to a newly-installed client computer, now a secondary installation computer, said new current installation probability, whereby said newly-installed secondary installation computer responds to installation requests with said new current installation probability.
9. A method of installing computer programs in a network according to claim 8, in which said reduction factor is \xbd, whereby said installing computer and said secondary installation computer have the same probability and the total probability of response of said installing computer and said secondary installation computer is the same as the previous probability of response of said installing computer.
10. A method of installing computer programs in a network according to claim 5, in which said first installing computer has a network address that is halfway in a network address range and said first installing computer assigns to each secondary installation computer installed by it a secondary installation computer network address range that is half of said first installing computer’s then-current network address range and a network address that is halfway in said secondary installation computer network address range.
11. A method of installing computer programs in a network according to claim 7, in which said first installing computer has a network address that is halfway in a network address range and said first installing computer assigns to each secondary installation computer installed by it a secondary installation computer network address range that is half of said first installing computer’s then-current network address range and a network address that is halfway in said secondary installation computer network address range.
12. A method of installing computer programs in a network according to claim 9, in which said first installing computer has a network address that is halfway in a network address range and said first installing computer assigns to each secondary installation computer installed by it a secondary installation computer network address range that is half of said first installing computer’s then-current network address range and a network address that is halfway in said secondary installation computer network address range.
13. An article of manufacture in computer readable form comprising means for performing a method of installing computer programs in a network having a set of computers comprising the steps of:
providing a first installation computer having operating software and installation software;
providing a set of at least one client computer broadcasting installation requests at a dynamically adjustable rate; in which a client computer initially broadcasts installation requests at an initial request rate and monitors the total installation request rate carried on said network, wherein said installation requests include requests for operating system software; and said client computer adjusts its own broadcast rate by comparing said total installation request rate with a target installation request rate and adjusting its own rate by an adjustment amount that depends on the difference between said total installation request rate and said target request rate;
said first installing computer responds to a first installation request and installs both said operating software and installation software on a first client computer of said set of computers, thereby establishing said client computer as a secondary installation computer, and during which installation operation, said first installing computer ignores installation requests;
upon completion of the first installation, both said first installing computer and said secondary installation computer service installation requests by installing both said operating software and installation software.
14. An article of manufacture according to claim 13, in which said adjustment amount is linearly proportional to said difference between said total installation request rate and said target request rate.
15. An article of manufacture according to claim 13, in which an installing computer responds to an installation request received by it in a probabilistic manner.
16. An article of manufacture according to claim 15, in which an installing computer responds to a first installation request received by it according to an initial reference probability.
17. An article of manufacture according to claim 16, in which an installing computer responds to an installation request received by it according to a current installation probability and, upon completing an installation request responded to by it reduces its current installation probability by a reduction factor to calculate a new current installation probability with which it will respond to future requests.
18. A computer system having a set of computers connected by a network and containing a set of computers operating a program in computer readable form adapted for carrying out a method comprising the steps of:
providing a first installation computer having operating software and installation software; in which a client computer initially broadcasts installation requests at an initial request rate and monitors the total installation request rate carried on said network, wherein said installation requests include requests for operating system software; and said client computer adjusts its own broadcast rate by comparing said total installation request rate with a target installation request rate and adjusting its own rate by an adjustment amount that depends on the difference between said total installation request rate and said target request rate;
providing a set of at least one client computer broadcasting installation requests at a dynamically adjustable rate; in which said first installing computer responds to a first installation request and installs both said operating software and installation software on a first client computer of said set of computers, thereby establishing said client computer as a secondary installation computer, and during which installation operation, said first installing computer ignores installation requests;
upon completion of the first installation, both said first installing computer and said secondary installation computer service installation requests by installing both said operating software and installation software.
19. A computer system according to claim 18, in which said adjustment amount is linearly proportional to said difference between said total installation request rate and said target request rate.
20. A computer system according to claim 19, in which an installing computer responds to an installation request received by it in a probabilistic manner.
21. A computer system according to claim 20, in which an installing computer responds to a first installation request received by it according to an initial reference probability.
22. A computer system according to claim 21, in which an installing computer responds to an installation request received by it according to a current installation probability and, upon completing an installation request responded to by it reduces its current installation probability by a reduction factor to calculate a new current installation probability with which it will respond to future requests.