Clinton R. Hanna

Recent developments in speed regulation

THE PROBLEM of automatically maintaining constancy of speed in rotating machinery is frequently encountered, aside from prime-mover governing, in such applications as d-c drives for a-c generators whose frequency must be kept unvarying to a high degree of accuracy for signalling purposes or for exacting test-floor operation. To satisfy the need for a means of effecting such speed regulation, an electrical governor has been developed and an analytical study has been made of the requirements for stable control of the governed system.

Automatic flight control system using rate gyros for unlimited maneuvering

Feedback control techniques have been applied to automatic flight control problems to produce a new type of automatic pilot. It provides unlimited maneuverability by using three simple nontumbling rate-type gyroscopes to regulate the angular velocity of the aircraft about its principal axes. The three basic control loops, without use of vacuum tubes, combine electric and hydraulic power boost means in proportional-type servomechanisms which actuate the aircrafts control surfaces.

Electrical engineering: Gyroscopic stabilizer for tank guns

IN 1939 the problem of stabilizing guns in tanks for the condition of traveling over rough terrain was presented by Colonel David J. Crawford, Ordnance Department, United States Army, then a captain at Aberdeen Proving Ground. Colonel Crawford had previously seen certain regulating devices involving the use of gyroscopes and felt that such a combination of equipment would be necessary in the solution of his problem. Consideration was given to this, and it was found that the required speeds and accelerations of the power drive for such a stabilizer were in excess of anything previously attempted. For example, the principal disturbances were at about 1 1/2 cycles per second corresponding to the pitching frequency of the tank on its springs, and displacements were such as to cause rates of about 30 degrees per second and accelerations of 300 degrees per second per second.

Achievements of co-operation

I AM DEEPLY GRATEFUL for the high honor accorded me by the Institute in the award of the Benjamin Garver Lamme Medal. My colleagues also share in this because without their ideas and effort much of the progress for which the citation was made would not have come to fruition.