Battelle Memorial Institute

G Frederick Renner

Robert B McCown

William Godwin Atterbury

James E Dvorsky

Jeremy M Harris

Nile F Hartman

Richard K Thatcher

Brian A Kelley

Typical apparatus as shown in FIGS. 1 and 12 for indicating the relative positions in a given direction between a reference point (24,59) and a test point (29,68) spaced therefrom and movable relative thereto is useful for measurement of the magnitude and direction of static or dynamic torque in a shaft (8). Overlapping transparent reference (20,60) and test surfaces (25,61), either parallel disks (60,61) or coaxial cylinders (20,25) each having a relevant portion covered with a plurality of equally spaced lines oriented predominantly normal to the given direction and at an angle to each other, produce moire fringes (30) when illuminated (14,15). One of the surfaces (25,61), being flexible, is connected to the shaft (8) so as to flex in response to torque between the reference point (24,59) and the test point (29,68), causing a change in the angle between the lines on the two surfaces (20,25;60,61), and thus of the spacing (D) (FIG. 3) of the moire fringe bands (30), which is optically detected (17) and converted, as shown in FIG. 4, to an electrical signal (42) to control power applied to the shaft (8).

Indicating positions

A tactile sensing apparatus having a piezoelectric energizing layer with a plurality of conductors disposed on one surface of a piezoelectric material and a plurality of conductors disposed on the opposite surface of the piezoelectric material, the plurality of conductors having electrical connections connected to electrical energizing means. An electrical insulating layer disposed adjacent the piezoelectric energizing layer. A second piezoelectric sensing layer is disposed adjacent the insulating layer, and has conducting surfaces disposed on opposite surfaces thereof. The conductors in the piezoelectric energizing layer provide N.times.M energizing areas with N+M electrical connections to the energizing layer. Further apparatus may include an oscillator, an optional amplifier and a switching means or multiplexer for the input signal. The apparatus may optionally have more than one piezoelectric energizing layer as well as more than one piezoelectric sensing layer. PVF.sub.2 is the preferred piezoelectric material. An optional base material and protective layer may be used. A method of operating the tactile sensor includes providing a variable frequency electrical signal at a frequency and amplitude adapted to energize the energizing areas. The signal is switched to the conductors to energize selected energizing areas of the energizing layer in a predetermined sequence. The signal generated in the sensing layer that varies in frequency and amplitude in response to an object in contact with the tactile sensor is processed for frequency and amplitude information to determine the characteristics of the object such as shape, force or weight.

Active multi-layer piezoelectric tactile sensor apparatus and method

A rotative coupling allows the inductive transmission of power and the transmission of informational signals between a stationary part and a hollow, rotating part. The informational signals are transmitted on a modulated beam of light passing through and along the axis of rotation of the hollow, rotative part. The power is transmitted by induction from a coil on the stationary part to a coil on the rotative part, both coils being positioned within stationary core means and the rotative core means, which combine to establish a continuous flux path around the coils.

Rotative power and signal coupling

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Columbus, OH, United States of America

G Frederick Renner