Abstract: A method for simulating a gas turbine including the steps of: sensing values of a plurality of first operating parameters of an actual gas turbine; applying the sensed values of the first operating parameters to a model of the gas turbine, wherein the model generates a plurality of predicted second operating parameters; determining difference values between the predicted second operating parameters and corresponding sensed second operating parameters of the actual gas turbine; modifying the difference values based on tuning factors generated by a Kalman filter gain matrix during operation of the gas turbine, and using the adjusted difference values to adjust the model of the gas turbine. The method may further comprise generating the tuning factors by applying to the model the sensed values of the plurality of first operating parameters and perturbated values of the adjusted different values to determine optimal tuning factors.

Abstract: A method is presented for representing anomalies to a process. These anomalies are represented in an anti-pattern, which depicts non-productive emergent information that describes activities that are detrimental to the progress of the process. The anti-pattern includes visually-coded areas that describe how severe the detrimental activities are to the process when combined. After the anti-pattern is created for the process, new non-productive emergent information for a current process is mapped onto the anti-pattern in the form of data patterns represented as visual fences. Appropriate steps are then taken to address the new non-productive emergent information, depending on the visually-coded area to which the new non-productive emergent information is mapped.

Abstract: In an optimum design method comprising a first solution determining step of solving an optimization problem of a first evaluation function for a state variable vector with a design variable vector being as a parameter, and a second solution determining step of solving an optimization problem of a second evaluation function for the design variable vector and the state variable vector thus obtained, the second solution determining step includes the steps of computing a gradient vector of the second evaluation function for the design variable vector, computing a first coefficient based on a value of a norm of the gradient vector, computing a search vector based on the first coefficient, computing a second coefficient, and updating the design variable vector based on the second coefficient.

Abstract: A method is disclosed for developing and using a high-speed adaptive multivariable controller by removing the dynamics of the PID controllers from a Model Predictive Controller that was developed using identification testing of a process. The resulting multivariable controller, based on final control elements as the manipulated variables is then used in a novel control adaptation with all of the PID controllers switched to manual.

Abstract: A temperature control scheme for a fuel cell stack thermal sub-system in a fuel cell system that uses a non-linear thermal model and disturbance rejection to provide an optimum stack temperature. The thermal sub-system includes a coolant loop directing a cooling fluid through the stack, a pump for pumping the cooling fluid through the coolant loop, and a radiator for cooling the cooling fluid outside of the fuel cell stack. The system includes a controller for controlling the speed of the pump so as to maintain the temperature of the stack at a desired temperature. The controller uses the thermal model to anticipate a temperature of the cooling fluid out of the fuel cell stack to control the speed of the pump.

Abstract: A position of a motion control axis is monitored and an output device responsive to the position of the motion control axis is controlled. The controlling further includes latching an electronic cam element that controls the output device, and unlatching the cam element that controls the output device. The manner in which the latching is performed and the manner in which the unlatching is performed are configurable in a programming interface. The programming interface is capable of receiving a latch position for the cam element and an unlatch position for the cam element. The programming interface is further capable of receiving additional configuration information to configure the manner in which the latching is performed and different additional configuration information to separately configure the manner in which the unlatching is performed.

Abstract: The present invention is a method for determining the optimum operating practice for an industrial process. The methodology includes a combination of process control steps and data analysis techniques to investigate responses to controlled “black box” process inputs, e.g., coal and air feeds for coal-fired furnaces in the case studies above. A unique time-dependent perturbation is applied to individual process feed streams to give a signature in the data that permits the filtering and detection of various measured responses, e.g., continuous emission monitor readings for NOx, SO2, CO2, CO, and opacity for regulated electric utility furnaces. The perturbation is implemented using the plant control system. Individual control signal set points are perturbed for each piece of equipment supplying process inputs of interest. As a result, complex commercial processes can be evaluated for optimization without changing the normal configuration of the system.

Abstract: A method includes receiving measurement data from at least one sensor at a first controller. The measurement data is associated with a process. The method also includes receiving a first output signal at the first controller. The first output signal is generated by a second controller and affects the process. The method further includes determining how to control at least a portion of the process using the measurement data and the first output signal. In addition, the method includes providing a second output signal, where the second output signal is operable to control at least the portion of the process. The second controller may be operable to use the second output signal to generate the first output signal.

Abstract: A Safety Instrumented System for use with a process control system receives pressure of process fluid in the process piping. A valve positioner positions a valve which controls flow of process fluid through the process piping. The valve positioner is caused to perform a partial stroke of the valve or otherwise introduce a perturbation into the process. A resulting change in sensed pressure due to the perturbation is used to diagnose operation of the process.

Abstract: A method is disclosed for developing and using a high-speed adaptive multivariable controller by removing the dynamics of the PID controllers from a Model Predictive Controller that was developed using identification testing of a process. The resulting multivariable controller, based on final control elements as the manipulated variables is then used in a novel control adaptation with all of the PID controllers switched to manual.

Abstract: The invention relates to a method in which at least one component of a technical plant is controlled by means of a PI controller. The actual value of the regulating parameter is continuously determined during operation of the plant and the amplification factor of the PI controller is altered depending on the time relationship of the actual value, until the actual value remains with a tolerance band relative to the set value. The invention further relates to a controller for carrying out said method.

Abstract: In an optimum design method comprising a first solution determining step of solving an optimization problem of a first evaluation function for a state variable vector with a design variable vector being as a parameter, and a second solution determining step of solving an optimization problem of a second evaluation function for the design variable vector and the state variable vector thus obtained, the second solution determining step includes the steps of computing a gradient vector of the second evaluation function for the design variable vector, computing a first coefficient based on a value of a norm of the gradient vector, computing a search vector based on the first coefficient, computing a second coefficient, and updating the design variable vector based on the second coefficient.

Abstract: A system and method for signal transmission and reception by narrow band chaotic bi-phase shift keying includes a forward error correction encoder for receiving input data, a data packetizer in signal communication with the forward error correction encoder, a compression encoder in signal communication with the data packetizer, a radio frequency link in signal communication with the compression encoder, a compression decoder in signal communication with the radio frequency link, a data depacketizer in signal communication with the compression decoder, and a forward error correction decoder in signal communication with the data depacketizer for recovering the input data by controlling the orbits of chaos; where the method includes the steps of transmitting a signal indicative of chaotic bi-phase shift keyed data, propagating the transmitted signal within a narrow frequency band, and receiving the propagated signal substantially without degradation of the indicated data by controlling the orbits of chaos.

Abstract: A method and apparatus for designing perturbation signals to excite a number of input variables of a system, in order to test that system for the purpose of obtaining models for the synthesis of a model-based controller. The method begins with providing input parameters of the system. A plurality of binary multi-frequency (BMF) signals are generated based on these input parameters and the frequency spectra of these BMF signals are calculated. One BMF signal is selected out of the set of BMF signals so that the frequency spectrum of the selected BMF signal most closely matches a desired frequency spectrum specified by the input parameters. The selected BMF signal is used as a first perturbation signal for testing the system. The selected BMF signal is also shifted by predetermined amounts of samples to create delayed copies of the original BMF signal to be used as additional perturbation signals.

Abstract: A controller which is capable of improving the resolution and accuracy of control even when controlling a plant including a control region in which nonlinearities are temporarily very strongly exhibited and a control region in which the nonlinearities are hardly exhibited. A controller 1 which controls fuel pressure Pf of a fuel supply system 10 includes an ECU 2. The ECU 2 sets a target fuel pressure Pf_cmd, calculates a first control input Rsld for causing the fuel pressure Pf to converge to the target fuel pressure Pf_cmd, with equations (1) to (6), modulates the first control input Rsld with equations (11) to (31) to thereby calculate a second control input Udsm, and depending on whether or not during fuel-cut operation or pressure decreasing control, selects one of the first and second control inputs Rsld and Udsm as the control input Upf.

Abstract: A control apparatus is provided for ensuring a high-level control resolution and a high control accuracy even when a plant exhibits strong and varying non-linear characteristics with a varying sensitivity of a control amount to a control input. The control apparatus for controlling a cam phase through a cam phase varying mechanism comprises an ECU. The ECU calculates an SLD control input for controlling a cam phase to converge to a target cam phase in accordance with a predetermined control algorithm, and calculate a control input to the cam phase varying mechanism by modulating the SLD control input in accordance with a predetermined modulation algorithm. The ECU also sets an amplitude setting value in accordance with the cam phase, an engine rotational speed, an oil pressure, and an oil temperature.

Abstract: A system and method for signal transmission and reception by narrow band chaotic frequency shift keying includes a forward error correction encoder for receiving input data, a data packetizer in signal communication with the forward error correction encoder, a compression encoder in signal communication with the data packetizer, a radio frequency link in signal communication with the compression encoder, a compression decoder in signal communication with the radio frequency link, a data depacketizer in signal communication with the compression decoder, and a forward error correction decoder in signal communication with the data depacketizer for recovering the input data by controlling the orbits of chaos; where the method includes the steps of transmitting a signal indicative of chaotic frequency shift keyed data, propagating the transmitted signal within a narrow frequency band, and receiving the propagated signal substantially without degradation of the indicated data by controlling the orbits of chaos.

Abstract: In a method and apparatus for predicting process results of objects being processed in a processing chamber of a processing apparatus, operation data and process result data obtained at the time of processing each of the objects are collected and a multivariate analysis is performed on the basis of the collected operation data and process result data to obtain a first correlation therebetween. Process results are predicted on the basis of the first correlation. Weighting coefficients for the respective operation data are set on the basis of the predicted process results. A second correlation between the weighted operation data and the process result data is obtained by a multivariate analysis. Process results are predicted by using operation data, obtained when objects other than the objects used to obtain the second correlation are processed, on the basis of the second correlation.

Abstract: A method for identifying a control path of a controlled system, and more particularly to a method for identifying a control path in the presence of deterministic perturbations is described. At least one deterministic perturbation correcting signal is determined in a first identification process, and the perturbation correcting signal is stored in the form of a function. A control path of the controlled system is identified in a second identification process by adding to the controlled system the at least one stored deterministic perturbation correcting signal with a negative feedback. The method can be used with machine tools, production machines and/or robots which demand a high control accuracy and/or a high-quality control characteristic. In particular, perturbation effects due to slot latching in motors, in particular linear motors, can be minimized.

Abstract: A method and apparatus are disclosed for performing an evaluation of the quality of performance of a service involving a person at a remote facility. The method comprises providing a user interface; viewing, on the user interface, a moving video representative of a station showing the person; and using a tool displayed on the user interface, the tool for collecting data regarding the quality of performance of a service in accordance with the video.

Abstract: There are provided a positioning control method and a positioning control device, which enables high speed positioning with low power consumption without repeating two or more acceleration and deceleration operations during travel from an original position to a target position. There is also provided an electronic component mounting apparatus, which enables high speed positioning with low power consumption and enables mounting of electronic components in a short period of time. When a movable body is moved from the original position to the target position, there is set an operational passing position for avoiding a passing avoidance region, and driving of a drive unit having a smaller travel distance from the original position to a coordinate of the operational passing position is started later than driving start timing of a drive unit having a longer travel distance, from the original position to another coordinate of the operational passing position, by a specified period of time.

Abstract: A device for calculating the steady state behavior of a controller includes an amount generating unit for generating the amount of deviation of the regulator, a first threshold value calculation unit that detects whether the amount of deviation of the regulator has fallen below a first threshold value and then starts a lag time delay unit, and a second threshold value calculation unit that detects whether the amount of deviation of the regulator has fallen below a second threshold value. A signal transmission unit transmits a ready message signal when the lag time delay unit has reached a predetermined lag time and the second threshold value calculation unit has detected that the amount of deviation of the regulator has fallen below the second threshold value.

Abstract: A method and apparatus for estimating a state parameter in a nonlinear discrete time system are provided. The method for estimating a state parameter has the steps of (a) predicting a state parameter at a current time using an estimated state parameter at a previous time and a system dynamics; and (b) estimating an optimal state parameter at the current time from the state parameter predicted in the step (a) and a system output parameter measured at the current time, using a geometric data fusion method. Since the method and apparatus for estimating a state parameter have an excellent estimation performance particularly when nonlinearity is great or the error in an estimated initial value is big, the method and apparatus solve many problems, which cannot be solved by the conventional extended Kalman filter, and more improve the performance of estimating a state parameter, by analyzing the system characteristic and then appropriately utilizing constraints such as the operation range of the state parameter.

Abstract: A method and apparatus for automatically adjusting the gains of a feedback controller while the process continues to run and the controller continues to operate and control the process is disclosed. A desired closed-loop control bandwidth and a target loop transfer function are specified by the operator, and the tuning is accomplished automatically with minimal operator intervention and without the need for developing a model of the process. The automatic tuner subjects the process to one or more disturbance and the operation of both the process and the controller are monitored.

Abstract: A method includes processing a plurality of workpieces in accordance with an operating recipe. Metrology data associated with the processing is collected. A control model including at least one tuning parameter having a default value is provided. A plurality of perturbations is introduced to shift the tuning parameter from its default value. Control actions are generated based on the metrology data and the perturbations to the tuning parameter in the control model to modify the operating recipe. An error signal associated with each of the perturbations is generated. The default value of the tuning parameter is modified based on the error signals.

Abstract: A simple method of handling thermomechanical coupling for temperature computation in a rolling tire. First, the sensitivity of the tire elastic response to changes in material stiffness is characterized using the “deformation index”. Then, using a commercial finite element program and an appropriate user subroutine, heat generation is expressed as a function of the local temperature using a simple algebraic expression involving the temperature dependent material properties and the deformation indices. Temperatures are computed using the finite element program with the coupling information contained in the user subroutine. The result is a non-iterative method for a fully-coupled thermomechanical analysis of a tire. The effects of compound changes on tire temperature distribution can also be estimated using the deformation index. The method applies to the energy loss and temperature calculations under both steady-state and transient conditions.

Abstract: A methodology for process modeling and control and the software system implementation of this methodology, which includes a rigorous, nonlinear process simulation model, the generation of appropriate linear models derived from the rigorous model, and an adaptive, linear model predictive controller (MPC) that utilizes the derived linear models. A state space, multivariable, model predictive controller (MPC) is the preferred choice for the MPC since the nonlinear simulation model is analytically translated into a set of linear state equations and thus simplifies the translation of the linearized simulation equations to the modeling format required by the controller. Various other MPC modeling forms such as transfer functions, impulse response coefficients, and step response coefficients may also be used. The methodology is very general in that any model predictive controller using one of the above modeling forms can be used as the controller.

Abstract: A method to produce natural motions, or self-motion, of animate or inanimate bodies or their parts by the application of pulses at two or more locations on the surface, or inside, of the bodies or their parts. Here, energy is converted into motion in one step. Turn on the pulses, and motion results instantly. The mechanism can emulate living motions, and as living motions can take on infinite gaits and forms, so can the mechanism produce infinite forms of motion. Smooth, repeatable, controllable or random motions can be induced. Just as living muscles convert the pulses from the nervous system into natural motion in one step, so will the mechanism convert artificially generated pulse-trains into motion in one step. The dynamic coupling or modulation of waves which travel within a body, and which are caused by artificially generated pulse-trains, produces the desired motions in directions perpendicular to the plane of the pulses.

Abstract: A multivariable process controller controls a chemical, polymer or other physical process. Slow tuning and over-conservative controlled variable values are employed during step testing. While all controlled process variables are within safe limits, only one manipulated variable (MV) at a time is step changed. Several manipulated variables are moved when process variables exceed safe limits to ensure that the controlled process variables return to the safe range, such that suitable MV targets for step testing are able to be automatically discovered within a closed loop control environment. Thus, the step test is able to be conducted mostly unsupervised and/or remotely via a telephone or network connection.

Abstract: A method for identifying a control path of a controlled system, and more particularly to a method for identifying a control path in the presence of deterministic perturbations is described. At least one deterministic perturbation correcting signal is determined in a first identification process, and the perturbation correcting signal is stored in the form of a function. A control path of the controlled system is identified in a second identification process by adding to the controlled system the at least one stored deterministic perturbation correcting signal with a negative feedback. The method can be used with machine tools, production machines and/or robots which demand a high control accuracy and/or a high-quality control characteristic. In particular, perturbation effects due to slot latching in motors, in particular linear motors, can be minimized.

Abstract: A control method and system are provided to sustain chaos in a nonlinear dynamic system. A sustained transient that is tracked as a system parameter is substantially varied thereby allowing sustained chaotic transients to exist far away from the crisis parameter values. The method includes targeting points near a chaotic transient once the iterates reach a neighborhood of an undesired attractor. Targeting is done so that the natural dynamics of the system would not engage again the iterations and chaotic motion. A brief parameter fluctuation forces the attractor to be a repeller so that a point which lies on the previously existing chaotic transient can be targeted. Consequently, instead of landing on the attractor, the iterations will reach a region of phase space where a chaotic transient is present, causing the chaotic motion to be reexcited.

Abstract: A device for calculating the steady state behavior of a controller includes an amount generating unit for generating the amount of deviation of the regulator, a first threshold value calculation unit that detects whether the amount of deviation of the regulator has fallen below a first threshold value and then starts a lag time delay unit, and a second threshold value calculation unit that detects whether the amount of deviation of the regulator has fallen below a second threshold value. A signal transmission unit transmits a ready message signal when the lag time delay unit has reached a predetermined lag time and the second threshold value calculation unit has detected that the amount of deviation of the regulator has fallen below the second threshold value.

Abstract: A multivariable analysis tool is provided wherein an orthogonal decomposition method such as a Partial Least Squares algorithm is applied to a disturbance model, which relates the known loop disturbances to the loop model residue. The tool according to the invention first extracts the most dominant correlation to the loop model residue and then uses the residue to search for secondary dominant correlation in an orthogonal space, and repeats this process until no further output variation can be significantly attributed by the next dominant correlation. In this way, the analysis tool of the present invention is able to estimate the performance potential of each control loop under different disturbance conditions and provide a control performance index by comparing the achieved performance to the performance potential in a multi-variable environment. This index indicates whether or not a given loop is under optimal operation and shows variance of the loop from the best achievable loop performance.

Abstract: Automatic speed loop gain adjustment of a feedback control system begins by setting up a phase margin range and a gain margin range. A speed open loop condition is provided by separating a speed command value from a speed feedback value. White noise is input into the feedback control system where the speed open loop condition has been made. A phase margin and a gain margin are then detected and comparisons are made with the phase margin range and the gain margin range, respectively. The speed loop gain is adjusted if the comparison results for either one of the detected phase margin and the detected gain margin fall outside of the associated phase margin range or gain margin range. Once the adjustment of the speed loop gain is complete, the position loop gain of the position control loop is adjusted on the basis of the adjusted speed loop gain.

Abstract: A controlling method and apparatus for positioning a robot that can output an optimal speed instruction for controlling residual vibration after completion of a moving operation, achieve reduction in tact time for the moving operation, and shorten the length of setting time. The method is a controlling method for positioning a robot (1) for performing a point-to-point moving operation comprising: performing a test operation to measure a frequency of a residual vibration that is stopped at a target position; measuring a magnitude of the residual vibration based on the frequency during each of different lengths of moving time for a predetermined moving distance to find a relationship between the length of moving time and the magnitude of the vibration; calculating a shortest moving time at which vibration magnitude is minimized; and performing the point-to-point operation for the calculated shortest moving time, thereby to position the robot (1) at the target position.

Abstract: In a method for prescribing an essentially linear ramp with a prescribable slope by a quantity, and which is clock-pulse-controlled and which describes the ramp by an increment per clock interval, the ramp is described by a number of regular increments and by at least one first and one second irregular increment. The regular increments exhibit a value corresponding to the prescribable slope. The irregular increments exhibit a value deviating from the prescribable slope. The first irregular increment is a first increment describing the ramp and the second irregular increment is a last increment describing the ramp.

Abstract: A system for establishing a table of correction values for detecting deviations from zero in a sensor module of a vehicle, wherein a sensor sensing the movement of the vehicle a sensor for sensing the temperature of the vehicle movement sensor and is provided, and a method for determining a corrected sensor signal and a sensor module for determining a corrected sensor signal.

Abstract: An industrial process material flow within an industrial process is controlled by a process control loop that includes a process controller, a field device controller and a field device in the process as well as process variable feedback from the process to the process controller. Both the process controller and the field device controller, such as a valve controller, are fine-tuned so that their interaction is taken into account and controller parameters, which provide an optimal control loop performance are found. This results in a significant improvement in the control loop performance, i.e., in a lower process variability, as compared with the traditional tuning method, which does not take into account the interaction between the two controllers.

Abstract: A method and apparatus for controlling a non-linear mill. A linear controller is provided having a linear gain k that is operable to receive inputs representing measured variables of the plant and predict on an output of the linear controller predicted control values for manipulatible variables that control the plant. A non-linear model of the plant is provided for storing a representation of the plant over a trained region of the operating input space and having a steady-state gain K associated therewith. The gain k of the linear model is adjusted with the gain K of the non-linear model in accordance with a predetermined relationship as the measured variables change the operating region of the input space at which the linear controller is predicting the values for the manipulatible variables.

Abstract: A method and arrangement for detecting a watermark in an information signal. The method may include the steps of computing the correlation (dk) of the watermark (Wi) and the information signal (e.g. an image Q) for a plurality of positions (k) of the watermark with respect to the information signal, and detecting whether at least one of the respective correlation values exceeds a given threshold. The step of detecting may include determining the standard deviation (&sgr;d) of the respective correlation values (dk), and setting the threshold to a given multiple (T) of the standard deviation. The multiple (T) is derived form a desired false alarm rate (watermark detected when there is none, or no watermark detected when there is one).

Abstract: Briefly, a preferred embodiment of the present invention includes an apparatus for tuning a regulator in a process controller. The digitized output from a standard relay and a parasitic relay are fed through digital to analog converter providing signals at 0.5&ohgr;c, &ohgr;c and 1.5&ohgr;c to the process, where &ohgr;c is the process critical frequency. The apparatus records the digitized relay output u′ and the digitized process output y′ until stationary oscillations are reached. The outputs u′ and y′ are then used to calculate the process frequency response at 0.50&ohgr;c, &ohgr;c and 1.5&ohgr;c. This data is then used to design the regulator, the output of which is converted to analog form and inputted to control the process.

Abstract: The invention relates to a method and an arrangement for controlling a sheet-making process. In the solution, a sheet matching desired values is manufactured. A measuring unit measures the state of the process to produce one or more measurement value representing the state of the process. A comparator compares each measurement value with a corresponding desired value and, on the basis of the comparison, forms an error representing the difference between at least one measurement value and desired value. A control unit forms at least two control action candidates based on the error using at least two process models, of which at least one is a perturbed process model. A processing unit forms one control action from the control action candidates, with which control action the sheet-making process is controlled to produce a sheet matching the desired values.

Abstract: A system and method for automatically tuning a fuzzy logic process controller is presented. A process under control is automatically assessed to determined process control characteristics including, for example, ultimate gain, ultimate period and time delay. Then, these quantities are used to calculate tunable control parameters which include scaling factors, which are applied to the fuzzy logic controller in order to optimize the performance of the fuzzy logic controller when connected to control the process.

Abstract: Systems and methods for reducing unwanted vibration in motion system are provided using a Robust Vibration Suppression (RVS) methodology, in which acceleration frequency spectra are obtained for each of a number of command input functions developed for moving a load a specified distance within a specified move time interval using an actuator. The frequency spectra comprise peaks, with notches defined between adjacent peaks. A desirable command input function is one with a frequency spectra having either a notch with a maximum width or a peak with a minimum magnitude relative to frequency spectra associated with other command input functions, or, alternatively, a peak with a magnitude of less than or equal to a pre-established magnitude or a frequency notch having a width greater than or equal to a pre-established width. A suitable command input function may be characterized by a ramp function, a cosine function, a sine function, or a combination thereof.

Abstract: A method for the estimation of the state variables of nonlinear systems with exogenous inputs is based on improved extended Kalman filtering (EKF) type techniques. The method uses a discrete-time model, based on a set of nonlinear differential equations describing the system, that is linearized about the current operating point. The time update for the state estimates is performed using integration methods. Integration, which is accomplished through the use of matrix exponential techniques, avoids the inaccuracies of approximate numerical integration techniques. The updated state estimates and corresponding covariance estimates use a common time-varying system model for ensuring stability of both estimates. Other improvements include the use of QR factorization for both time and measurement updating of square-root covariance and Kalman gain matrices and the use of simulated annealing for ensuring that globally optimal estimates are produced.

Abstract: A plurality of random probing sequences are used to perturb a corresponding plurality of cross-machine direction (CD) actuators of a web manufacturing machine. The web of sheet material is measured as the CD actuators are perturbed. The global process machine direction (MD) dynamics is estimated and a CD response is estimated for each of the plurality of CD actuators using the plurality of random probing sequences, measurements of the web of sheet material and the estimated global process MD dynamics. The estimated global process MD dynamics and the estimated CD responses form 2D responses for the plurality of CD actuators. To refine the 2D responses, the estimates of global process MD dynamics, and CD responses for each of the plurality of CD actuators are iterated. The actuator dynamics of the plurality of CD actuators may also be estimated and used in the estimates of the global process MD dynamics of the plurality of CD actuators and CD responses for each of the plurality of CD actuators.

Abstract: An adaptive, discrete-time sliding mode controller (SMC) is disclosed which detects and adapts to gain variations in the controlled plant. The overall control effort is generated by combining a linear control effort with a discrete-time sliding mode control effort generated by switching between gains in order to drive the system's phase states toward a sliding line trajectory. A sliding mode variable &sgr;k defines the position of the system phase states relative to the sliding line. The SMC controller is designed such that the sliding mode variable &sgr;k crosses the sliding line and changes sign at every sample interval. For the nominal plant gain, the SMC controller is also designed such that the magnitude of the sliding mode variable &sgr;k+1=−&sgr;k will remain constant (&sgr;k+1=−&sgr;k) and substantially constrained to |&sgr;k|=&Dgr;/(1+&lgr;) where &Dgr; and &lgr; are predetermined design constants.

Abstract: A model predictive controller for a process control system which includes a real-time executive sequencer and an interactive modeler. The interactive modeler includes both a process model and an independent disturbance model. The process model represents the dynamic behavior of the physical process, while the disturbance model represents current and future deviations from the process model. The interactive modeler estimates current process states from the process model and input data received from the executive sequencer. The executive sequencer then projects a set of future process parameter values, which are sought to be controlled, over a predetermined control horizon. The interactive modeler then solves a set of equations as to how the physical process will react to control changes in order to determine an optimized set of control changes. As a result, the process control system will be able to accurately track a predetermined set-point profile in the most effective and cost efficient manner.