Abstract: Battery backed memory for use in an industrial controller allows software disconnect of the battery and memory so that unplanned power outages may receive the benefit of battery backup, but battery power is not unduly wasted during planned power outages when data loss may be accommodated or other provisions may be made for saving data in nonvolatile memory.

Abstract: A method for fabricating MEMS structure includes etching a recess in an upper surface of a substrate that is bonded to a wafer that ultimately forms the MEMS structure. Accordingly, once the etching processes of the wafer are completed, the recess facilitates the release of an internal movable structure within the fabricated MEMS structure without the use of a separate sacrificial material.

Abstract: In a MEMS device employing a beam supported by transverse arms, potential bowing of the transverse arms caused by fabrication processes, temperature or local self-heating from resistive losses is accommodated by flexible terminations of the transverse arms. Alternatively, this bowing is controlled so as to provide selective biasing to the beam or mechanical advantage in the sensing of beam motion.

Abstract: A system and method for employing a file system and file system services on the industrial controller. The file system allows industrial control programs to implement many functions previously performed within the industrial control program and stored in the same memory as the industrial control program. An execution engine is provided that interprets instructions included in an industrial control program. The instructions utilize services in the file system for including user defined routine files loaded from local or remote locations, to load and unload recipe files from local and remote locations, to log and retrieve measured data and trend data to files at local or remote locations, to select different operating systems and to select a running program from a plurality of running programs utilizing the file system.

Abstract: A microelectromechanical system (MEMS) analog isolator may be created in which an actuator such as an electrostatic motor drives a beam against an opposing force set, for example, by another electrostatic motor. Motion of the beam may be sensed by a sensor also attached to the beam. The beam itself is electrically isolated between the locations of the actuator and the sensor. The structure may be incorporated into integrated circuits to provide on-chip isolation.

Abstract: A method for fabricating MEMS structures includes etching a recess in either an upper surface of a substrate that is bonded to a wafer that ultimately forms the MEMS structure, or to the lower surface of the wafer that is bonded to the substrate. Accordingly, once the etching processes of the wafer are completed, the recess facilitates the release of an internal movable structure within the fabricated MEMS structure without the use of a separate sacrificial material. Furthermore, a bridge, which is preferably insulating, is pre-etched before the wafer is attached to the substrate.

Abstract: A MEMS structure is provided having a cap that encapsulates and protects the fragile components of the device, while having an electrical trace embedded in a nonconductive substrate. The electrical trace includes a first terminal end that is exposed to the peripheral region of the device, and a second end that is connected to the MEMS structure to facilitate operation of the device.

Abstract: A method for fabricating an electrically isolated MEMS device having an outer stationary MEMS element and an inner movable MEMS element is provided that does not use a sacrificial layer. Rather, a pair of spacers are defined on the outer portions of the upper surface of a conductive wafer, and an insulating material is deposited thereon. The spacers are attached to a substrate to define an internal void therein. The wafer is then patterned to form the outer MEMS element as well as a conductive member for the inner MEMS element, separated from the outer MEMS element by a gap. A portion of the insulating layer that is disposed in the gap is then removed, thereby releasing the inner MEMS element from the stationary MEMS element.

Abstract: A method and apparatus are disclosed for performing timely execution of periodic tasks in a redundant control system. A secondary controller in the redundant system receives a wakeup time array having at least one wakeup time element corresponding to a periodic task as well as a current time value from a primary controller, and schedules a run time for the periodic task at switchover based on the wakeup time element and the current time value from the primary control module. The secondary controller may further receive a task instance corresponding to the periodic task from the primary control module, and schedule a run time for the periodic task at switchover based on the task instance. In addition, the secondary controller may schedule a run time for the periodic task at switchover based on a default period associated with the periodic task, if no task instance and no wakeup time element were received corresponding to the periodic task.

Abstract: Battery backed memory for use in an industrial controller allows volatile memory to be retained in instances of line power loss. A method and apparatus are disclosed for providing assurance that sufficient battery voltage was present during the entire power down period to maintain data integrity.

Abstract: An industrial control output device is provided which provides electrical isolation between device power and field power. The device includes two isolation devices, one of which is adapted to energize a power switching device, and the other is adapted to de-energize the switching device. The output device thus minimizes or reduces EMI/RFI emissions and provides fast switching times in selectively providing power to a load. In addition, the invention includes a method of providing power to a load in an industrial control system, which allows fast switching of a digital output with minimal or reduced EMI/RFI emissions.

Abstract: A method for fabricating an electrically isolated MEMS device is provided that uses surface fabrication techniques to form a conductive stationary MEMS element, and a movable MEMS element spaced apart from the conductive stationary MEMS element. The movable element includes a nonconductive base which provides for electrical isolation between a plurality of conductive members extending from the base. Modifications to the basic process permit the incorporation of a wafer-level cap which provides mechanical protection to the movable portions of the device.

Abstract: A system and method is provided for monitoring the operating condition of a pump by evaluating fault data encoded in the instantaneous current of the motor driving the pump. The data is converted to a frequency spectrum which is analyzed to create a fault signature having fault attributes relating to various fault conditions associated with the pump. The fault signature is then input to a neural network that operates in conjunction with a preprocessing and post processing module to perform decisions and output those decisions to a user interface. A stand alone module is also provided that includes an adaptive preprocessing module, a one-shot unsupervised neural network and a fuzzy based expert system to provide a decision making module that operates with limited human supervision.

Abstract: A method and system are provided for executing a control function or program which minimizes or overcomes the shortcomings of conventional systems. The invention allows a user of a distributed control system to place one or more control devices into a step mode, wherein the devices will execute a specified number of iterations of their internal logic or control programs, or execute such programs for a specified time period, and then stop or suspend execution. The user may then perform system diagnostics, for example, by interrogating certain modules to obtain output and input values, etc. The system may then be further iterated and the method repeated, so as to enable the identification of logic programming and/or hardware problems in a system.

Abstract: The invention comprises a modem apparatus adapted to provide full messaging and communications interface between a control device and a communications medium such as a telephone line. The modern can comprise an interface adapted to communicate directly with a control system device, such as a programmable logic controller (PLC), using a communications protocol compatible with the normal network communications used in a distributed control system. The apparatus advantageously interfaces directly with unmodified control system devices, providing the ability to send and receive messages from remote devices or personnel via a communications medium. The invention also comprises a control system including a modem device providing full communications between a control device and remote personnel and/or devices.

Abstract: A method and system for processing timers are presented in which a plurality of unordered timer lists may be kept according to timer duration. At least one timer list is processed selectively according to a counter associated with the timer list. The method and system reduce the processing overhead associated with timers via the selective processing of the list, and further result in little or no overhead increase as the number of active timers increases. A system is also provided for processing timers, which may include multiple timer lists.

Abstract: The present invention provides for a test system having a test executive software system for performing tests on units under test. The test executive software system includes a test kernel component that provides control through a generic interface to the test executive software. Test components, instrument components, support objects and a test system interface component are communicatively coupled to the test kernel component. The instrument components can be written as a dynamically linked library (DLL) file so that the instrument component can be broken into basic functional modules associated with the particular instrument type. Each instrument component supports operation in both live mode and virtual mode, so that testing can be performed in both normal mode and simulation mode. Virtual mode allows instruments to be inserted and removed without impacting test applications that do not utilize them, thereby reducing tester downtime.

Abstract: A highly reliable industrial control system provides for the processing of redundant control signals on as little as a single serial network without overloading the network by preprocessing input signals for coincidence and sending only the coincidence signal either periodically or on a change of state. Further compression of sent data is realized by extracting a reduced subset of transmission states from the input signals and transmitting only the transmission states.

Abstract: A method and apparatus are provided which allow a user to define an output device behavior in a variety of status and/or event circumstances via creating a binding or logical connection between a logic function and one or more status/event indicators. The method provides for user-defined output behavior through linking a logical function with system and module status/event indicators, whereby the output value may be determined according to the status/event indicators and user-defined function blocks. Also disclosed is an output device with an output providing an output signal according to an output value, a communication interface adapted to receive messages from a network, an indicator adapted to receive message information from a network and providing indicator data, and a logic unit which receives message information from the network, indicator data from the indicator, and which performs a logic function.

Abstract: A highly reliable industrial control system is produced such as may use a standard network for configuration by symmetrically transmitting configuration data to intercommunicating controller components. The configuration data provides a unique identification to each component to reduce the possibility of misdirected messages and provides the protocols to be used by the components reducing the chance of garbled messages. The two components trade configuration data prior to communicating to ensure that they have the correct party.