In the exemplary embodiments, the apparatus comprises: an ultrasonic transducer arrangement; a drive arranged to pivotably displace the transducer arrangement within a predetermined angular range; an actual-value generator for supplying a signal (F.sub.I (.rho.) dependent upon the angular position of the transducer arrangement within the said range; a desired-value generator for supplying a signal (F.sub.S (.rho.)) representing a desired angular position of the transducer arrangement within the said range; and a control for controlling the drive in dependence upon such signals from the actual-value and desired-value generators. The actual-value and desired-value generators are adapted to supply respective signals having the same or similar forms over a relatively large signal range within the said range.
An ultrasonic transducer probe having a mechanically steerable acoustic element includes a linear motor having a stationary magnet assembly and a coil bidirectionally linearly movable with respect to the magnet assembly. A mechanical arrangement formed of a pair of spaced apart, rotatably mounted pulleys and a flexible belt connecting the pulleys couples the coil and an ultrasonic transducer or acoustic element. The transducer element is mounted for rotation with at least one of the pulleys so that linear motion of the motor coil is converted to rotative motion of the transducer whereby the transducer and the ultrasonic beam it emits is caused to sweep through a selected angular sector. A position sensor formed of a supplemental stationary magnetic material and a position coil mounted for movement with the motor coil is utilized for detecting the linear position of the coil and, correspondingly, the angular orientation or position of the transducer element.
A scanner which includes a motor for driving a load and circuitry for providing a position error signal responsive to the difference between a predicted position of the load and the actual position of the load, preferably a mirror scanning a scene. The motor is driven in response to the position error signal. The position error signal is provided plural times during a single scanning of the scene. The circuitry for providing a position error signal includes a closed loop filter system for filtering the error signal to provide a filtered error signal, an adaptive filter system for operating on the filtered error signal to provide an adaptively filtered error signal and summing circuitry for summing signals indicative of the predicted position, the filtered error signal and the adaptively filtered error signal. The closed loop filter system includes, in series, at least one first order lead lag filter and a double integral plus proportional filter. The adaptive filter system includes, in series, a low pass filter, a register and an integrator.
An ultrasonic inspection tool (100) for inspecting the brazed joint (76) between two generator stator coils (18A and 18B) and an interconnecting copper bar (74). The inspection tool (100) is automatically serially positioned at a plurality of inspection sites on the surface of the copper bar (74). At each site an ultrasonic signal is emitted from the tool (100) and the return echo is sensed. Analysis of the return echo at each of the plurality of sites determines the characteristics of the brazed joint (76) at the site, from which a determination can be made as to the quality of the joint between coils (18A and 18B) and the copper bar (74).
An ultrasonic probe assembly in which an ultrasonic transducer is mechanically scanned in response to a drive motor which is located in a housing spaced from the transducer such that the transducer can be positioned in a body cavity of patient while the housing containing the drive motor remains outside the body of the patient.
An ultrasonic probe assembly in which an ultrasonic transducer is mechanically scanned in response to a drive motor which is located in a housing spaced from the transducer such that the transducer can be positioned in a body cavity of a patient while the housing containing the drive motor remains outside the body of the patient.