Abstract: A method for tracking a variable resonance condition in a plasma coil during creation of plasma from a gas flowing in a plasma torch adjacent to the plasma coil comprises: providing a radio-frequency (RF) power source comprising a power amplifier that generates a radio-frequency power signal with an adjustable operating frequency; providing a high-voltage ignition charge from said RF power source to the gas in plasma torch so as to create an electrical discharge through said gas so as to create a test sample comprising a partial plasma state within said plasma torch; and applying an RF power signal from said plasma coil to said test sample in said plasma torch, wherein said adjustable operating frequency of said power amplifier tracks said variable resonance condition of said plasma coil such that said test sample in the plasma torch achieves a full plasma state.

Abstract: A method for tracking a variable resonance condition in a plasma coil during creation of plasma from a gas flowing in a plasma torch adjacent to the plasma coil comprises: providing a radio-frequency (RF) power source comprising a power amplifier that generates a radio-frequency power signal with an adjustable operating frequency; providing a high-voltage ignition charge from said RF power source to the gas in plasma torch so as to create an electrical discharge through said gas so as to create a test sample comprising a partial plasma state within said plasma torch; and applying an RF power signal from said plasma coil to said test sample in said plasma torch, wherein said adjustable operating frequency of said power amplifier tracks said variable resonance condition of said plasma coil such that said test sample in the plasma torch achieves a full plasma state.

Abstract: A system and method are disclosed for implementing a power source including a power amplifier that generates a radio-frequency power signal with an adjustable operating frequency. The power amplifier also generates a reference phase signal that is derived from the radio-frequency power signal. An impedance match provides the radio-frequency power signal to a plasma coil that has a variable resonance condition. A phase probe is positioned adjacent to the plasma coil to generate a coil phase signal corresponding to the adjustable operating frequency. A phase-locked loop then generates an RF drive signal that is based upon a phase relationship between the reference phase signal and the coil phase signal. The phase-locked loop provides the RF drive signal to the power amplifier to control the adjustable operating frequency, so that the adjustable operating frequency then tracks the variable resonance condition.

Abstract: A system and method are disclosed for implementing a power source including a power amplifier that generates a radio-frequency power signal with an adjustable operating frequency. The power amplifier also generates a reference phase signal that is derived from the radio-frequency power signal. An impedance match provides the radio-frequency power signal to a plasma coil that has a variable resonance condition. A phase probe is positioned adjacent to the plasma coil to generate a coil phase signal corresponding to the adjustable operating frequency. A phase-locked loop then generates an RF drive signal that is based upon a phase relationship between the reference phase signal and the coil phase signal. The phase-locked loop provides the RF drive signal to the power amplifier to control the adjustable operating frequency, so that the adjustable operating frequency then tracks the variable resonance condition.

Abstract: A system and method are disclosed for implementing a power source including a power amplifier that generates a radio-frequency power signal with an adjustable operating frequency. The power amplifier also generates a reference phase signal that is derived from the radio-frequency power signal. An impedance match provides the radio-frequency power signal to a plasma coil that has a variable resonance condition. A phase probe is positioned adjacent to the plasma coil to generate a coil phase signal corresponding to the adjustable operating frequency. A phase-locked loop then generates an RF drive signal that is based upon a phase relationship between the reference phase signal and the coil phase signal. The phase-locked loop provides the RF drive signal to the power amplifier to control the adjustable operating frequency, so that the adjustable operating frequency then tracks the variable resonance condition.

Abstract: A mobile robot which has a guidance and navigation system (sometimes called a "vision" system) employing one or more arrays of ultrasonic transducers and, preferably, one or more infrared detectors, as well. Each of the ultrasonic transducers is arranged to monitor its own sector of the robot's workspace. Sector monitoring is facilitated by providing for each such transducer a horn fronting the transducer; at least part of the horn's surface is covered by ultrasonic energy absorptive material. According to a second aspect of the invention, the robot is used in conjunction with an infrared beacon system including one or more (preferably ceiling-mounted) beacons each of which emits a uniquely coded infrared signal. The robot is equipped with an infrared detection means affixed to the robot and arranged to allow light from the beacon to impinge on an infrared sensor only when the detector is in precise alignment with the beacon.

Abstract: A vision system for a mobile robot employs at least two arrays of sensors for obtaining data on the position and distance of objects in a workspace. One of the sensor arrays is used principally to see near objects and the other array is used principally to see far objects. The two arrays are symmetric about an axis that extends through the body of the robot. The robot carries a computer which controls the sequence in which the sensors are serially polled for information. Data received from the sensors is stored and provides a representation of the space and objects seen by the sensors. A software program causes the computer to manipulate data from the sensors to simulate rotation of the robot around the axis of symmetry and control behavior of the robot to complete goals set by input commands from a natural language processor.