Methods and devices are provided for gathering impedance data related to implantable restriction devices. In general, the methods and devices can enable patients, health care providers, and others to use gathered data as a feedback mechanism to non-invasively monitor efficacy of an implantable restriction device in a patient and to identify, modify, and/or prescribe a treatment plan for the patient considering the gathered data. Impedance data can be gathered and analyzed for tissue proximate to the restriction device, e.g., a fat pad between a gastric band and the patient's stomach. Electrodes in contact with the tissue can measure an impedance of the tissue, with the impedance between the electrodes changing as the tissue reduces in size (e.g., as fat cells shrink) and/or changes configuration.

Methods and devices for measuring impedance in a gastric restriction system

A temperature control system for a thermal reactor is disclosed that addresses many of the problems in the art. In accordance with one aspect of the disclosed control system, a plurality of temperature controllers are employed. Each temperature controller employs one or more dynamic models that are optimized for a given temperature range. The temperature range over which a particular controller is optimized is preferably generally exclusive of the temperature ranges over which other controllers of the plurality of temperature controllers are optimized. In accordance with another aspect of the control system, the control system employs enhanced ramp trajectory logic. In accordance with another aspect of the control system, the control system employs a virtual temperature sensor in the event of a hardware failure of the corresponding non-virtual temperature sensor. Upon the detection of a failure of the non-virtual temperature sensor, the temperature control system automatically substitutes a virtual temperature sensor in its place as a control system input. In accordance with a still further aspect of the temperature control system, the control system is provided with control logic that switches the control mode of the system in the event of a failure of a heating element. All of the foregoing aspect of the present invention may be combined into a single temperature controller. Alternatively, these temperature control system improvements may be incorporated as individual elements, without reliance on the other inventive aspects disclosed herein.

Temperature control system for a thermal reactor

A distributed processing unit (DPU) or drop which performs process control and data acquisition functions in a distributed processing control system having a data highway linking a plurality of such units. A DPU functional processor accesses the local process I/O interface thereby continually receiving plant information for storage in digital form and subsequent use in the functional processor or for transmission along the data highway. DPU control programs use process values in a transparent fashion, that is without regard to whether these values were obtained through local process I/O interface or via the data highway. The DPU software structure is made up of execution software and support software. The execution software is a collection of data acquisition and process control programs which are developed at an engineer's console drop using a DPU programming language which operates in text and CRT graphic display modes, the latter programming modes allowing system documentation via hard copy graphic display printout. These programs are initiated, performed consecutively, and repeated at specified intervals. The support software initiates process loop execution. Control programs which have been presented to the DPU as representations of ladder diagrams for sequential control or process flow diagrams for continuous process control are executed in the DPU functional processor to achieve the required process control operation.

Universal process control device and method for developing a process control loop program

An implantable restriction device is configured to provide a restriction in a patient as a function of the pressure of fluid. The implantable restriction device includes one or more pressure sensors configured to sense pressure of the fluid within the implantable restriction device. Pressure data obtained by the one or more pressure sensors may be communicated to a device located external to the patient, such as a data logger, using telemetry coils or other communicators. The data logger may store the pressure data, and may communicate the pressure data to a remote location via a network such as the Internet. A docking station may be provided to couple the data logger to a network and/or to recharge a cell in the data logger.

Monitoring of a food intake restriction device

An implantable system having internal circuitry configured to withstand a pre-determined amount of sterilization radiation is provided. In general, the system includes an internal control module in electrical communication with an implantable medical device. The internal control module can include a circuit board configured to withstand radiation and/or any number of integrated circuits (e.g., application specific integrated circuits) wherein the circuits or at least some portion thereof are fabricated so as to withstand some amount of radiation. For example, some portion of the circuitry can be fabricated utilizing radiation compliant material(s), silicon-on-insulator technology, and/or gallium arsenide technology. Additionally, the circuitry can include various components which are inherently resistant to such radiation (e.g., components fabricated utilizing magnetic field based technology, surface acoustical wave devices, etc.). A method of sterilizing an implantable medical device via radiation is also provided.

System and method of sterilizing an implantable medical device

A method and apparatus are provided for producing a control signal by digital computation for controlling an element affecting a process. The process is described by a sequence of activities, and the onset of each activity is marked by a predetermined change of a process parameter. An event detector is provided for detecting the occurrence of predetermined changes of process parameters in response to data included within event detector data blocks. The event detector data blocks include data defining the desired response to the detection of a predetermined change of a process parameter. The control signal is produced in accordance with a selected predetermined algorithm using data included in algorithm data blocks. A first event detector data block and a first algorithm data block are selected defining a first predetermined change of a process parameter and a first algorithm. Upon detection of the first predetermined change, of a process parameter, a second predetermined change of a process parameter is selected in accordance with data included within the first selected event detector data block and a second algorithm data block is selected defining a second algorithm.

Method and apparatus for process control

A machine control system including a programmable machine function controller comprised of a logic processor and a data processor. The logic processor is responsive to first devices on a machine, e.g. limit switches and push buttons, for controlling second devices on the machine, e.g. motor starters and solenoids, in accordance with a program representing a desired machine operation. The data processor operates asynchronously with the logic processor but responds thereto for selecting programs of arithmetic instructions relating to the machine operation. The system includes a panel of push buttons, lights and read-outs located remotely from the controller. Signals are transmitted between the controller and the panel using asynchronously operating receiver/transmitters which multiplex and transfer the signals on a serial basis. The machine includes at least one movable member in mechanical communication with a driving mechanism. The controller employs circuits which are responsive to the data processor and logic processor for producing signals to the driving mechanism to control the motion of the movable element.

Machine control system employing a programmable machine function controller

Plural electrical loads supplied with power from a single source are monitored to detect defective loads. Each load is periodically individually energized and current delivered by the source is measured. Measured current for each load is compared with limit values to detect abnormal values. To overcome consequences of supply voltage fluctuations, supply voltage is also measured and admittance of each load is determined from measured current and measured voltage. The admittance value thus determined for each load is compared with limit values to detect abnormal values. Load monitoring of loads energized according to a control algorithm proceeds by periodic momentary suspension of energization according to the control algorithm and energization of selected individual loads.

Dennis Grover O'keefe

Papers

Method and apparatus for process control

Machine control system employing a programmable machine function controller

Method and apparatus for monitoring electrical loads

Maschinensteuersystem mit einem programmierbaren maschinenfunktions- regler