Abstract: Methods and systems for automatically locating and identifying labware using radio-frequency identification (RFID) tags are described herein. The methods and systems include a plurality of RFID tags (pre-programmed with unique data codes) that are associated with labware (or labware holders). For example, the RFID tags can be embedded within the locating pegs of the labware (or labware holders). The methods and systems also include a plurality of RFID tag readers that mount near known locations of an instrument deck which receives the labware. The RFID tag readers automatically scan for the presence of RFID tags such that when a piece of labware is added to the instrument deck, and then report to a processing device the specific known location on deck where each tag was found, as well as the unique data code of each tag. Using this information, the methods and systems determine one or more of the location, orientation, and identity of the received labware.

Abstract: Methods, systems, and computer program products for measuring a capacitance between a probe and a liquid, pausing movement of the probe based on a rate of change of the capacitance, further measuring the capacitance while the probe is paused, and, based on the further measurements, performing one or more of: resuming movement of the probe, determining a position of the probe, aspirating liquid into the probe, and dispensing from the probe. Resuming movement of the probe can include returning iteratively to measuring a capacitance, and the further measuring can be performed for a time interval that can vary based on the further measured capacitance(s), a probe movement characteristic, and/or a sampling rate.

Abstract: Methods and systems for automatically locating and identifying labware using radio-frequency identification (RFID) tags are described herein. The methods and systems include a plurality of RFID tags (pre-programmed with unique data codes) that are associated with labware (or labware holders). For example, the RFID tags can be embedded within the locating pegs of the labware (or labware holders). The methods and systems also include a plurality of RFID tag readers that mount near known locations of an instrument deck which receives the labware. The RFID tag readers automatically scan for the presence of RFID tags such that when a piece of labware is added to the instrument deck, and then report to a processing device the specific known location on deck where each tag was found, as well as the unique data code of each tag. Using this information, the methods and systems determine one or more of the location, orientation, and identity of the received labware.

Abstract: Methods, systems, and computer program products for measuring a capacitance between a probe and a liquid, pausing movement of the probe based on a rate of change of the capacitance, further measuring the capacitance while the probe is paused, and, based on the further measurements, performing one or more of: resuming movement of the probe, determining a position of the probe, aspirating liquid into the probe, and dispensing from the probe. Resuming movement of the probe can include returning iteratively to measuring a capacitance, and the further measuring can be performed for a time interval that can vary based on the further measured capacitance(s), a probe movement characteristic, and/or a sampling rate.

Abstract: Methods and systems for automatically locating and identifying labware using radio-frequency identification (RFID) tags are described herein. The methods and systems include a plurality of RFID tags (pre-programmed with unique data codes) that are associated with labware (or labware holders). For example, the RFID tags can be embedded within the locating pegs of the labware (or labware holders). The methods and systems also include a plurality of RFID tag readers that mount near known locations of an instrument deck which receives the labware. The RFID tag readers automatically scan for the presence of RFID tags such that when a piece of labware is added to the instrument deck, and then report to a processing device the specific known location on deck where each tag was found, as well as the unique data code of each tag. Using this information, the methods and systems determine one or more of the location, orientation, and identity of the received labware.

Abstract: Methods, systems, and computer program products for measuring a capacitance between a probe and a liquid, pausing movement of the probe based on a rate of change of the capacitance, further measuring the capacitance while the probe is paused, and, based on the further measurements, performing one or more of: resuming movement of the probe, determining a position of the probe, aspirating liquid into the probe, and dispensing from the probe. Resuming movement of the probe can include returning iteratively to measuring a capacitance, and the further measuring can be performed for a time interval that can vary based on the further measured capacitance(s), a probe movement characteristic, and/or a sampling rate.

Abstract: Methods, systems, and computer program products for measuring a capacitance between a probe and a liquid, pausing movement of the probe based on a rate of change of the capacitance, further measuring the capacitance while the probe is paused, and, based on the further measurements, performing one or more of: resuming movement of the probe, determining a position of the probe, aspirating liquid into the probe, and dispensing from the probe. Resuming movement of the probe can include returning iteratively to measuring a capacitance, and the further measuring can be performed for a time interval that can vary based on the further measured capacitance(s), a probe movement characteristic, and/or a sampling rate.

Abstract: Methods and systems for automatically locating and identifying labware using radio-frequency identification (RFID) tags are described herein. The methods and systems include a plurality of RFID tags (pre-programmed with unique data codes) that are associated with labware (or labware holders). For example, the RFID tags can be embedded within the locating pegs of the labware (or labware holders). The methods and systems also include a plurality of RFID tag readers that mount near known locations of an instrument deck which receives the labware. The RFID tag readers automatically scan for the presence of RFID tags such that when a piece of labware is added to the instrument deck, and then report to a processing device the specific known location on deck where each tag was found, as well as the unique data code of each tag. Using this information, the methods and systems determine one or more of the location, orientation, and identity of the received labware.

Abstract: The present methods and systems include aligning at least two sensors with one or more known locations, selecting at least two of the at least two sensors, electrically driving the probe, based on signals received by the selected sensors, determining whether the probe is aligned with the known location(s), and, optionally adjusting the probe position based on the determination. The methods and systems also include repeatedly returning to electrically driving and positioning the probe until the probe is aligned with the selected sensors, and/or repeatedly returning to selecting at least two of the at least two sensors. The relative position of the probe with respect to the selected sensors may also be determined.

Abstract: Methods, systems, and computer program products for measuring a capacitance between a probe and a liquid, pausing movement of the probe based on a rate of change of the capacitance, further measuring the capacitance while the probe is paused, and, based on the further measurements, performing one or more of: resuming movement of the probe, determining a position of the probe, aspirating liquid into the probe, and dispensing from the probe. Resuming movement of the probe can include returning iteratively to measuring a capacitance, and the further measuring can be performed for a time interval that can vary based on the further measured capacitance(s), a probe movement characteristic, and/or a sampling rate.

Abstract: A method and apparatus for preventing or limiting damage to capillaries used to dispense microdrops measures the voltage produced by a piezoelectric transducer when the capillary contacts a solid surface or the phase shift occurring when the piezoelectric transducer is operated at its resonant frequency. After distinguishing the voltage created from such contact from the voltage produced from unrelated random sources, corrective action is taken, in one aspect by stopping the relative movement of the capillary and the surface being contacted. The method and apparatus may also be employed to determine the position of a solid or liquid surface. In one embodiment, the method and apparatus of the invention is used to detect contact of the capillary with very small liquid droplets.

Abstract: A method and apparatus for preventing or limiting damage to capillaries used to dispense microdrops measures the voltage produced by a piezoelectric transducer when the capillary contacts a solid surface or the phase shift occurring when the piezoelectric transducer is operated at its resonant frequency. After distinguishing the voltage created from such contact from the voltage produced from unrelated random sources, corrective action is taken, in one aspect by stopping the relative movement of the capillary and the surface being contacted. The method and apparatus may also be employed to determine the position of a solid or liquid surface.

Abstract: An arrangement senses a liquid level by monitoring the peak capacitance formed between a probe and the liquid as the probe approaches or departs from the liquid. In an automated system, a computer controls the position of a pipette probe for aspirating or dispensing liquid in the vessel. The charge developed via the capacitance on the probe is coupled to a capacitive sensor circuit which provides a peak detector with an amplified signal representing the peak capacitance between the probe and the liquid. This amplified signal is detected by a peak-capacitance discrimination circuit, the output of which is monitored by the computer for determining the precise position of the probe with respect to the liquid surface level. Other aspects of the present invention include a negative-static elimination circuit coupled to the output of a detector latch and a positive-static elimination circuit coupled to the input of the detector latch.

Abstract: Apparatus for generating hydrogen by the electrolysis of water comprising an electrolytic cell having a cathode and an anode separated by a solid electrolyte, an electrical power supply connected to the cell for applying a voltage across the cathode and anode, a water reservoir connected to the cell for supplying water to the anode side, a hydrogen-water separator connected to the cell for receiving hydrogen and water from the cathode side and separating the hydrogen from the water, and a water return line connecting the hydrogen-water separator to the water reservoir for returning water to the water reservoir whereby the water is recycled to the anode side. A float valve in the upper region of the hydrogen-water separator closes the hydrogen outlet in response to an increase in the water level in the separator to the level of the hydrogen outlet, to prevent water from entering the hydrogen outlet in the event of a malfunction.