Honeywell-measurex Corporation

Measurex Corporation

Asyst Technologies, Inc.

Xiaohua George He

Kuoting Mike Tao

Ramesh Balakrishnan

George Tannous

Salem Abuzeid

An intelligent minienvironment control system designed to optimize the minienvironment performance, improve the protection for the multi-million dollar equipment within a fab, and to improve the safety conditions for fab personnel. The intelligent minienvironment control system is comprised of a plurality of minienvironment control and monitoring systems (MCMSs), one such system being associated with each minienvironment in the fab. The MCMSs continuously monitor the environmental conditions within the minienvironments. Each of the MCMSs are linked together in a local area network to form an integrated fab-wide minienvironment management system. The management system also includes workstations linked to the network for storing historical data for, and allowing remote access to, each of the MCMSs in the system.

Intelligent minienvironment

A control system regulates a controlled process. A first controller receives at least a first input variable and a second input variable and produces at least a first control variable and a second control variable. A delay unifier associated with the first controller introduces a first delay to one of the first and second control variables, the first delay being determined as a function of a second delay associated with another of the first and second control variables. A processor models effects of the controlled process. The processor receives the delayed first and second control variables output by the first controller and produces estimates of the process output variables. A second controller processes a difference between measured process output variables and the estimated process output variables to correct for disturbances. The processed difference is added to the delayed first and second control variables output by the first controller, and the sum is received by the processor and the process being controlled.

Method and system for controlling a multiple input/output process with

The present invention is directed to a method and apparatus for filtering a signal of a control and/or signal processing system in a manner which achieves both rapid tracking of signal transients (e.g., step changes in the signal) and heavy filtering of noise during steady-state operation. In accordance with exemplary embodiments, nonlinear features are combined with a conventional exponential filter to achieve both of these objectives. Exemplary embodiments are easy to use in a control and/or signal process system, and perform in a highly accurate manner. For example, in accordance with exemplary embodiments, a filter is configured with a deadband component which constitutes the sole adjustable component of the filter.

Method and apparatus for nonlinear exponential filtering of signals

The present invention relates generally to the control of processes which include relatively long time delays, yet which are susceptible to transient external disturbances, such as high-speed sheetmaking processes. Exemplary embodiments include a control system architecture that combines internal model-based control with state feedback in a manner which provides robust control, yet provides rapid rejection of external transient disturbances even in processes including relatively long time delays.

Method and apparatus for internal model control using a state variable

A control system regulates a controlled process. A first controller receives at least a first input variable and a second input variable and produces at least a first control variable and a second control variable. A delay unifier associated with the first controller introduces a first delay to one of the first and second control variables, the first delay being determined as a function of a second delay associated with another of the first and second control variables, and outputs first and second control variables with unified delay. A processor models effects of the controlled process. The processor receives the delayed first and second control variables output by the first controller and produces estimated process output variables. A second controller processes a difference between measured process output variables and the estimated process output variables to correct for disturbances. The processed difference is added to the delayed first and second control variables output by the first controller, and the sum is received by the processor and the process being controlled.

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Menlo Park, CA, United States of America

Xiaohua George He