![]() ![]() "Court of the General Tax Session of the Peace Justices," Family Trails, May 1984: 28-30 "Cotton Gin for Natchez, 1795," Louisiana Genealogical Register, December 1993: 314-15 "Concordia Ferry," Louisiana Genealogical Register, September 1974: 201-07 ![]() ![]() (1972)Ĭity of Natchez Records: Financial, Legal and Otherwise, 1847-1888. History of the First Presbyterian Church of Natchez, Mississippi. "Britain Loses Natchez, 1779: an Unpublished Letter," Journal of Mississippi History, January 1964: 45-46Ĭasey, Albert Eugene. Early Will Records of Adams County, Mississippi. "American Arrivals at Natchez, 1788," Mississippi Genealogical Exchange, Summer 1984: 66Īndrews, Johnnie. Farrar's Deed to Kingston Church, 1874," Journal of Mississippi History, April 1956: 135-41 "1860 Mortality Schedule," Mississippi Genealogy and Local History, June 1979: 65 The control system of claim 2, wherein the tangential pendulation and the radial pendulation are determined by a plurality of nonlinear equations of motion, the plurality of equations being a function of hoist-line length 元, gravity g, luff angle &bgr, slew angle &agr, tangential rotation angle &thgr 1, and a radial rotation angle &thgr 2, wherein the command shaping filter is a function of the plurality of equations, and wherein a design for the command shaping filter comprises: a simplification of the nonlinear equations of motion and a reduction of the residual payload pendulation frequency. A control system for filtering input commands to a rotary boom crane to reduce payload pendulation, wherein the rotary boom crane comprises a crane column horizontally rotatable about a vertical axis, a luffing boom mounted with the crane column, a variable-length hoist-line attached to the distal end of the luffing boom, and an operator input device for the input commands, wherein a payload suspended from the hoist-line is moveable in a horizontal and a vertical plane responsive to the operator input device, the payload having a tangential pendulation and a radial pendulation, wherein the control system comprises: a) an input command sensor, responsive to the input commands from the operator input device, the input commands comprising a commanded hoist velocity and b) a plurality of motors, operationally connected and responsive to the plurality of velocity servo controllers to achieve the filtered hoist velocity, the filtered luff velocity, and the filtered slew velocity. Inventive control thus acts on a continual basis to significantly reduce pendulation during the two-crane lifting operation. , minimum norm) solutions are transmitted by the computer to respective luff angle actuators and hoist line length actuators of both cranes so that the suspended payload tends toward steadiness. Inverse kinematic control signals in accordance with the mathematical (e. , zero motion horizontally, vertically, and rotationally in the same vertical geometric plane) of the suspended payload. ![]() The sensory signals are processed by the computer using a ship motion cancellation algorithm, which solves for values of the respective luff angles and hoist line lengths of both cranes, such values achieving static equilibrium (e. Sensory signals indicative of ship motion, and of luff angle and hoist line length of both cranes, are transmitted to a computer. The present invention is typically embodied to exert active control of two same-shipboard cranes performing joint lifting of a payload.
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