U.S. patent application number 10/679553 was filed with the patent office on 2004-04-08 for software enabled control for systems with luminent devices.
Invention is credited to Sanchez Olea, Jorge.
Application Number | 20040068511 10/679553 |
Document ID | / |
Family ID | 36814690 |
Filed Date | 2004-04-08 |
United States Patent
Application |
20040068511 |
Kind Code |
A1 |
Sanchez Olea, Jorge |
April 8, 2004 |
Software enabled control for systems with luminent devices
Abstract
A software enabled control method that allows dynamic
configuration of the operation of a control system. The
configuration can be done in a factory calibration or while the
system is running in the field in communication with a Host
computer. The Host computer may communicate through a serial or
parallel I/O. Because the control system has an expert system with
built-in mathematical models and intelligence for the system with
luminent devices, once the software enabled control system has been
configured and given set points for desired target performance, it
will regulate performance of the system with a luminent device in a
manner that does not require intervention of the Host computer. The
system contains performance optimization monitors based on
predetermined criteria. The results of the monitors are available
to the user or a Host computer through one of the available I/Os.
The present invention allows flexibility to address various
luminent devices using the same software architecture and similar
algorithms. The present invention has a control system that can be
configured to address a specific luminent device allowing for
compensation of manufacturing. The control system also has
algorithms that can be dynamically changed in light of changing
environmental conditions.
Inventors: |
Sanchez Olea, Jorge; (Poway,
CA) |
Correspondence
Address: |
George T. Parsons
2736 Aegean Drive
San Diego
CA
92139-3211
US
|
Family ID: |
36814690 |
Appl. No.: |
10/679553 |
Filed: |
October 6, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10679553 |
Oct 6, 2003 |
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09724692 |
Nov 28, 2000 |
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6629638 |
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60457095 |
Mar 24, 2003 |
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Current U.S.
Class: |
1/1 ;
707/999.1 |
Current CPC
Class: |
H01S 5/06825 20130101;
H04B 10/66 20130101; H01S 5/0617 20130101; H01S 5/068 20130101;
H01S 5/06804 20130101; G01R 31/002 20130101; G01R 1/071 20130101;
H01S 5/06832 20130101; H01S 5/06812 20130101 |
Class at
Publication: |
707/100 |
International
Class: |
G06F 007/00 |
Claims
I claim:
1. A method used to configure a control system for a luminent
device consisting of a Host computer with a configuration database,
and an embedded software enabled control system, wherein said
method consists of loading said system with information affecting
configuration and performance.
2. The software enabled control system according to claim 1,
wherein said system further consists of: modular software
architecture, and a configurable method of operation, wherein the
method of operation of the control system is determined by the
rules and models provided by a system configuration residing in
memory.
3. The software enabled control system according to claim 2,
wherein said system is hardware agnostic and uses a database to
configure the system to a specific electronic and optical hardware
platform, and further wherein in said system the resolution of the
analog to digital converters and the digital to analog converters
is determined by settings in a database
4. The software enabled control system according to claim 2,
wherein programs can be downloaded by said Host computer for the
purpose of modification of a control algorithm for a luminent
device or a system containing a luminent device.
5. The software enabled control system according to claim 2,
wherein said system further contains built-in criteria and
performance monitors to check for compliance with predetermined
criteria set points embedded in said Configuration database by said
Host computer.
6. The software enabled control system according to claim 2,
wherein said system further contains internal gages, which reflect
performance of the system controlled.
7. The gages according to claim 6, wherein said gages indicate
remaining life of the system based on a built-in model.
8. A luminent device automatic characterization process consisting
of analog sensor inputs and outputs and, an embedded algorithm,
which collects data corresponding to a characteristic transfer
function for said luminent device.
9. The luminent device characterization process according to claim
8, wherein collected data undergoes processing through mathematical
formulas and statistical analysis to obtain a luminent device
characteristic.
10. A servo control for a luminent device comprising: a
mathematical model for said luminent device, a feedback control
system, and a set of analog and digital I/Os in a hardware
configuration, wherein said servo control system can be modified
while it is in operation by changing servo parameters in an
embedded system configuration.
Description
REFERENCES
[0001] This application is a continuation in part patent for
pending application for the Electro-Optic System Controller and
method of operation Ser. No. 09/724, 692. This utility patent is
also filed based on Provisional Application No. 60/457, 095 titled
Software Enabled Control System for Electro-Optic Device.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The invention relates to methods used to control a system
containing a luminent device. Possible luminent devices can be, but
are not limited to, a laser, a light emitting diode, and a cold
cathode fluorescent light. The invention teaches methods for
control that rely on mathematical models that can be configured
dynamically in order to satisfy the requirements for any luminent
device. A Host processor carries out the configuration.
[0004] 2. Description of the Prior Related Art
[0005] Present approaches use a variety of solutions. Existing
control approaches for luminent device systems are generally based
on specific analog or digital circuits to implement functions. The
specific nature of these control approaches renders them inflexible
and unable to change when the luminent device is changed, or with
changing environmental conditions, situations in the field, or with
the type of application. Changes to address different conditions
need to be carried out with a laborious and time-consuming process
of design and characterization. In the specific case of laser
controls, some existing control systems utilize a variety of
methods in circuit form or programmed in a processor. These methods
are dependent on some form of control dependent on a specific
algorithm. The prior art methods rely on an external
characterization of the laser. These methods also are fixed for a
specific laser. Many prior art methods also rely on elaborate and
hardware-oriented implementations used to address the specific
application. Any adaptations or changes to these controls also
require laborious redesign and operation cannot easily be changed
in the field as the luminent device ages.
SUMMARY OF THE INVENTION
[0006] Software enabled control is a method that allows dynamic
configuration of the operation of a control system. The
configuration can be done in a factory calibration or while the
system is running in the field under the communication with a Host
computer. The Host computer may communicate through a serial or
parallel I/O. Because the control system has an expert system with
built-in mathematical models and intelligence for the system with
luminent devices, once the software enabled control system has been
configured and given set points for desired target performance, it
will regulate performance of the system with a luminent device in a
manner that does not require intervention of the Host computer. The
configuration database is generally not available to the user to
ensure the system containing a luminent device is not accidentally
changed. For some applications, the Host computer may be allowed
access to portions of the Configuration database in order to modify
the operation of the system. The system contains performance
optimization monitors based on predetermined criteria. The results
of the monitors are available to the user or a Host computer
through one of the available I/Os.
[0007] An advantage of the present invention is that it allows
flexibility to address various luminent devices using the same
software architecture and similar algorithms. Thus, maximum
leverage of code can be achieved.
[0008] Another advantage of the invention is that the control
system can be configured to address a specific luminent device
allowing for compensation of manufacturing.
[0009] Another advantage of the invention is that it is hardware
agnostic. The control system can be configured to reside in a mixed
signal microcontroller an ASIC or any other type of computer.
[0010] Yet another advantage of the software-enabled control is
that models can be dynamically changed in light of changing
environmental conditions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a System Configuration Method for a software
enabled control system for luminent devices.
[0012] FIG. 2 illustrates a Software Enabled Control System for
luminent devices.
[0013] FIG. 3 is a Servo Control for a Luminent Device, and
[0014] FIG. 4 shows an embodiment of the Configuration
Database.
DETAILED DESCRIPTION OF AN EMBODIMENT
[0015] There are four elements, which are part the Software Enabled
Control for Systems with Luminent Devices. These elements are:
[0016] 1. System configuration method;
[0017] 2. Software Enabled Control System is a system that is
reconfigurable and uses embedded intelligence and decision-making
to control hardware or mathematical objects used in a luminent
system;
[0018] 3. A configuration database; and
[0019] 4. Dynamic performance optimization.
[0020] System Configuration Method
[0021] FIG. 1 illustrates a system configuration method 100 for a
Software Enabled Control System 106. The method 100 consists of a
Host computer 101 used for configuration of the Control System 106.
The Host computer can also be part of a larger system. Some
examples of larger systems are a network, a liquid crystal display
unit, or system containing one or more lasers. The Host computer
101 contains a Configuration Database 102. The Configuration
Database 102 contains information necessary to configure the
control system 106. Some examples of the type of information in the
Configuration Database 102 are: Parameters used in a servo loop
control algorithm, gain and offset scaling, and calibration factors
for sensors used in the luminent device system, dynamic adjustments
of wavelength for a laser, or selection of a control or calibration
equation product. The Configuration Database 102 information is
sent to the control system by means of a Host computer I/O 103,
which can be serial or parallel. Data is sent to a Controller 104.
The Controller is the hardware where the software enabled control
system resides. The Controller 104 may contain processing
functions, embedded programs, analog signal acquisition, and analog
or digital I/Os. The database information 102 is placed in a
Configuration Memory 105, which may be part of the Controller 104
but can also be an additional unit, such as a permanent storage
unit consisting of optical or electrical storage technology. To
create a new application, the Host Computer 101 retrieves
configuration data from a database and places the appropriate
information into the Configuration Memory 105, which is part of the
Software Enabled Control System 106. By changing the information in
the Configuration Database 102, the control system 106 then is able
to apply control in the most optimal manner to the luminent system
under control. Examples of data in the Configuration Database 102
are parameters for embedded equations, firing voltage for a
fluorescent lamp, and information regarding electronic circuit
connections.
[0022] Once the configuration is complete, the Software Enabled
Control System 106 is able to operate on its own without any
assistance from the Host Computer 101 in the most optimal
manner.
[0023] The Controller 104 is connected to the Luminent Device
System 107 by means of General Purpose I/Os 108. These I/Os consist
of digital input and output signals and analog inputs. The General
Purpose I/Os 108 are used to obtain feedback information, and to
issue control directions. The Luminent Device System 107 contains
luminent devices and a variety of hardware used to produce light of
various types. Examples of luminent devices are laser diodes, gas
lasers, LEDs, and Cold Cathode Fluorescent Lights (CCFLs).
[0024] The Luminent Device System 107 may also consist of sensors,
electronic drivers, electro-optical devices, and special purpose
integrated circuits. The reader will appreciate that the Luminent
Device System 107 can be any device or system circuit that has the
objective of generating light of any form.
[0025] Software Enabled Control System
[0026] The Software Enabled Control System 106 is a software or
firmware engine with embedded processes, algorithms, and special
agents with an expert system. The engine is provided with specific
details regarding the System 106 with Luminent Devices 107 by the
data in the Configuration Memory 105. Once the Software Enabled
Control System 106 is given the specific configuration information,
it will operate independently to effectively control any luminent
device.
[0027] FIG. 2 illustrates one of the numerous possible
architectures for the Software Enabled Control System 106. The
Software Enabled Control System 106 consists of an Operating System
201, which directs the operation of the various programs and the
assignment of system resources. The Operating System 201 provides
the flexibility to connect a variety of programs to be used by the
control system in a modular fashion. A System Configuration 202 is
a database, which contains the information necessary to set the
specific modes of operation of the Control System 106 and also
contains multiple mathematical models for the Luminent Device
System 107. The Luminent System Controls 203 consist of a set of
programs used to carry out controls of specific devices within the
Luminent Device System 107. Examples of these type of programs are
laser driver controls, pulse width modulators used to control cold
cathode fluorescent lamps, laser wavelength tuner controls, and
thermoelectric cooler controls. The Luminent System Controls 203
contain mathematical models and rules which are modified depending
on the information set in the system configuration. The Host
Communication Interface 204 is a program used to communicate with a
Host Computer. Communication may be done through a serial I/O or a
parallel I/O using a specific Serial I/O Driver 205 or Parallel I/O
driver 206 respectively. Numerous protocols can be utilized.
Examples of these protocols are 12C and RS232. The choice of the
protocol for communication with the Host Computer is made by a
selection in the system configuration.
[0028] The Analog I/O Drivers 207 are a set of programs that
determine how the Control System 106 interacts with analog devices
used in the Luminent Device System 107. In a specific embodiment of
a hardware implementation, the Analog I/O Drivers 207 may control
analog to digital converters, or digital to analog converters. An
Analog Signal Calibrator 208 is a software module used to process
the input or output signal from the analog interfaces to the
hardware in order to obtain precision data. For example, regarding
analog inputs, the Analog Signal Calibrator 208 will contain an
equation for each of the inputs. The equations may be linear or
nonlinear and allow the program to apply corrections to the
incoming analog data in order to obtain a high level of precision
in the measurement. If a specific analog input behaves in a linear
manner, the correction equations will be an equation of the form
y=mx+b. The parameters m and b specific for the sensor will reside
in the System Configuration 202 and will be loaded by the Host
Computer 101 either at the factory or in the field where the Host
101 is part of a larger system.
[0029] The Expert System for Luminent Device Automatic
Characterization 209 is a program, which characterizes the specific
luminent device in a system. Due to manufacturing variations, a
luminent device will exhibit variations in performance as
determined by the specification parameters. An example of luminent
device parameter variation is found in a control system for the
Cold Cathode Fluorescent Lights. Each lamp will generally have a
different strike voltage (voltage needed to first turn on a
fluorescent lamp). In the case of a laser control system, each
laser will have a different threshold and slope efficiency. The
Expert System for Luminent Device Automatic Characterization 209
will utilize the analog inputs and outputs to collect data when the
system is powered up. The data collected is analyzed with
mathematical and statistical tools to obtain a performance profile
for the specific part. The performance profile is used to update
model equations which in turn are used in conjunction with Luminent
Device Controls 203 to drive the luminent device in the correct
manner to obtain acceptable performance. The Expert System for
Luminent Device Automatic Characterization 209 is initialized with
the selection of an algorithm used to obtain the characteristic
profile. Selection is carried out through a flag that is set in the
System Configuration 202.
[0030] Luminent Device Controls 203 consist of a set of algorithms
used to drive a luminent device. The control algorithms may be
servo controls, or other type of controls. The Luminent Device
Controls 203 are initialized for the specific luminent device with
parameters in the System Configuration 202. For example, in the
case of a servo type of control, the System Configuration 202 will
store the damping coefficient and the servo gains used for the
servo control of the luminent device.
[0031] FIG. 3 illustrates a model for servo control of the lamp
output. Luminent Device Controls 210 are a set of programs used to
control the operation of the luminent device. These programs may
consist of servo controllers or another type of control programs.
Some other programs in the Luminent Device Controls 210 are the
result of a characterization of the luminent device. The
characterization is then rendered to a model, which resides in the
Luminent Device Controls 210. The System Configuration 202 then
determines how the model is applied. As an example, consider the
performance of a laser diode over temperature. The slope efficiency
(output power per current into the laser), threshold current, and
wavelength vary in accordance to generally nonlinear relationships
versus temperature. These relationships can be rendered into a
formula with parameters. The parameters are initialized in
accordance with data in the System Configuration 202, thereby
allowing the customization of the control for a specific unit. The
objective of the Luminent Device Controls 203 is to obtain a set
point for any performance parameter of a luminent device.
[0032] An embodiment of the Luminent Device Controls 210 is a servo
control system. Servo systems have traditionally been used in
motion control applications. This invention uses servos to solve
problems with for luminent devices.
[0033] FIG. 3 illustrates a Servo Control for a Luminent Device
300. Starting with a set point 301, the System 106 will
continuously operate in a manner that will automatically adjust an
Output 307 to the value of the set point 301. The Output 307 is any
controlled variable of a luminent device 306. Examples of
controlled variables are luminance of a Cold Cathode Fluorescent
Lamp or, the wavelength, power, or current of a laser. An error 303
corresponds to the difference between the set point and the
measured value of the Output 307 as given by a Feedback 302. A
Servo Controller 304 is a control process that determines the best
way to drive the luminent device 306 in order to maximize the speed
at which the Set Point of the control variable is achieved in a
smooth and stable manner. The Servo Control for a Luminent Device
300 also consists of one or more Sensors 308 that measure the
Output 307. Once the Output 307 is measured, the signal is
digitized with an A/D converter 309 and may be processed with a
Signal Processor 310 to maximize signal to noise ratio.
[0034] Servo controls offer numerous advantages. Since there is a
continuous monitoring and adjustment of the Output 307, the result
is very precise. The various elements of the block diagram can be
calibrated to a high degree of precision with appropriate
parameters in the System Configuration 202. In addition, the
various blocks of the servo can be configured to address the
control of any controlled variable.
[0035] Configuration Database
[0036] FIG. 4 shows an embodiment of a Configuration Database 400
used for a laser control system. Column 401 displays examples of
the diversity of parameters that the database contains. Parameters
such as Laser Servo Gain, Servo Damping Coefficient, Measured
Feedback, and Set Point for Extinction Ratio modify the performance
of a feedback control system. The Overload detector and Eye Safety
Shutdown settings modify operation of built-in programs. Threshold
Detector Result and Temperature are results from measurements,
which continually change while the Software Enabled Control System
106 is running and will generally be assigned to RAM locations.
Flag for Selection of Laser Control Program selects from various
programs for laser control the best match to the application.
Scaling Factors for Drivers, Analog input 1 sensor offset, and
Analog input 1 sensor gain relate to calibration of a sensor input
and allow the use a variety of hardware platforms. Temperature
coefficient for slope efficiency and the Exponential for Threshold
equation modify mathematical models for laser characteristics in
order to customize the control to a specific device. More than one
model of temperature compensation can be made available depending
on the specific laser. The specific compensation is chosen with the
Flag to select the type of temperature compensation. The TEC set
point and Wavelength set point are used to set the target values
for servos used in wavelength tuning applications. The System
resolution entry in the Configuration database 400 allows the use
of A/D and D/A converters with 16, 12, 10, 8 or less bits of
resolution. The Receiver gain setting is used to control the gain
of an amplifier used in an optical receiver. Column 402 is the
symbol for the parameter in the database. The Value 403 of the
parameter in the Configuration Database 400 is loaded through a
data path 404, which uses a serial or parallel I/O. The data is
provided by a Host computer 101 in the factory or in a field
installation for a system or product.
[0037] Dynamic Performance Optimization
[0038] The software enabled control system contains built-in
intelligence to regulate performance of the system with luminent
devices. Once the system has been configured, it is independent of
the Host computer 101. The Software Enabled Control System 106 is
capable of generating its own diagnostics with built-in data
monitors. One of these monitors is a Servo data log. The objective
of the Servo data log function is to record the information of the
critical parameters that determine servo performance. Whenever a
servo loop is executed, the values of several servo variables are
recorded in RAM. Examples of stored variables in the servo
performance monitor are:
[0039] PM. (Measured feedback),
[0040] Err (loop error),
[0041] PS (set point),
[0042] PCONT (Servo control value), and
[0043] Drive (Driver input to modify variable)
[0044] The System 106 has predetermined criteria in the
Configuration database 400 used to check results of the servo
operation. The criteria can be degree of stability of the
controlled variable. All of the information obtained from the
operation of the software enabled control system 106 is dynamically
updated. This information includes performance measures, digital
I/O port and analog I/O port status. The information can be made
available to the Host computer 101 to inform the status of
performance gages. Examples of gages are the percent of life
remaining for the luminent device or any other failure mechanisms
encountered that may warrant part replacement.
* * * * *