Abstract: A system for controlling an ultrasonic transducer utilizes an indication of the relative phase of the voltage on the transducer and the current passing through the transducer to control the relative phase to a value that has been preselected to correspond to resonance of an electromechanical system that includes the ultrasonic transducer. In one example application, the system includes a waveform generator that produces an oscillating signal, and the frequency of the oscillating signal is adjustable under control of the control processor. The control processor adjusts the frequency of the oscillating signal according to a proportional control law at least some of the time, and according to a proportional-integral control law at least some of the time. The control processor may also control the amplitude of the oscillation of the ultrasonic transducer.

Abstract: A system for controlling an ultrasonic transducer utilizes an indication of the relative phase of the voltage on the transducer and the current passing through the transducer to control the relative phase to a value that has been preselected to correspond to resonance of an electromechanical system that includes the ultrasonic transducer. In one example application, the system includes a waveform generator that produces an oscillating signal, and the frequency of the oscillating signal is adjustable under control of the control processor. The control processor adjusts the frequency of the oscillating signal according to a proportional control law at least some of the time, and according to a proportional-integral control law at least some of the time. The control processor may also control the amplitude of the oscillation of the ultrasonic transducer.

Abstract: A cartridge in which sonication is applied to biological matter to disrupt and release nucleic acids from the matter is formed from a cartridge body containing a series of wells connected by fluid passages engineered to prevent backflow, with at least one well containing a sonication window covered by a thin lamina to transmit sonic vibrations from a sonication horn contacting the exterior surface of the window. Fluid transport among the wells is achieved by pressure differentials through the fluid passages, and a succession of functions is performed in the various wells, including disruption, mixing, binding of the released nucleic acids to binding materials, washing, elution, and collection.

Abstract: Methods and apparatus for precise positioning of an object using linear actuators based on linear stepper motors operating in microstepping or full step mode, a control algorithm based on compensation table, and a calibration apparatus for obtaining the compensation table.

Abstract: Methods and apparatus for precise positioning of an object using linear actuators based on linear stepper motors operating in microstepping or full step mode, a control algorithm based on compensation table, and a calibration apparatus for obtaining the compensation table.