GB483635A - Improvements in or relating to electric systems for controlling the position of a controlled object - Google Patents

Abstract

483,635. Electric control systems. HULL, H. L., SPERRY GYROSCOPE CO., Ltd., and SPERRY GYROSCOPE CO., Inc. July 20, 1936. No. 17232. Addition to 473,753. [Class 40 (i)] In the position control system claimed in the parent Specification wherein a controlled object is driven into a predetermined angular position relatively to a controlling object, by driving means which are controlled in accordance with the relative angular displacement of the objects and its second derivatives, viz. acceleration, the driving means are also controlled in accordance with the velocity derivative, the acceleration and velocity derivatives being obtained by reactance and resistance elements included in a network. The Figure shows a circuit wherein an output voltage V for controlling the driving means is composed of three voltages V<3>, V<2>, V<1> proportional to displacement, velocity and acceleration and derived from an input voltage v which is proportional to the relative displacement. The voltage V<1> is produced by a transformer having capacity C in series with its primary and consequently is proportional to the first derivative of the capacity current and therefore to the second derivative of the voltage v assuming the impedance of C is high relatively to that of the transformer. The voltage V<2> is derived from a second transformer having a resistance G in its primary circuit so that the voltage V<2> is proportional to the first derivative of the primary current and therefore to the first derivative of v. The voltage V<3> is tapped off directly from a resistance R and is proportional to v. The circuit arrangement may be modified so as to effect the operation of a pair of oppositely-connected gas-discharge tubes, Fig. 8 (not shown). An additional constant bias voltage for the tubes may be introduced into the control circuits. Several circuits are described for producing the first and second derivatives involving different connections of the condenser, resistance and transformer. Specification 480,115 is referred to.