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Jacklin, S. A.

Publications and source records attributed to Jacklin, S. A..

Design Considerations for High-Speed Control Systems

Existing hardware integrated into versatile, high-speed control system. Report discusses five global design considerations to integrate array-processor, multimicroprocessor, and host-computer system architectures into versatile, high-speed controllers. Such controllers are capable of control throughputs as high as 36 MHz for 8-bit bytes and maintain constant interaction with non-real-time or user environment. Application example, architecture of high-speed, closed-loop controller used to control helicopter vibration actively discussed.

Jacklin, S. A.

System identification techniques for helicopter higher harmonic control

This paper presents and compares several system identification techniques proposed for use with higher harmonic control algorithms designed to alleviate helicopter vibration. All method for actively controlling helicopter vibration require the knowledge of how the vibration outputs are related to the control inputs. Off-line or batch identification methods for obtaining this knowledge are presented first. Then the more advanced, adaptive identification techniques proposed to track the helicopter model parameters in flight are discussed. Considerations regarding system identifiability, identification algorithm stability, and computer implementation are also discussed.

Jacklin, S. A.

High-speed, automatic controller design considerations for integrating array processor, multi-microprocessor, and host computer system architectures

Modern control systems must typically perform real-time identification and control, as well as coordinate a host of other activities related to user interaction, online graphics, and file management. This paper discusses five global design considerations which are useful to integrate array processor, multimicroprocessor, and host computer system architectures into versatile, high-speed controllers. Such controllers are capable of very high control throughput, and can maintain constant interaction with the nonreal-time or user environment. As an application example, the architecture of a high-speed, closed-loop controller used to actively control helicopter vibration is briefly discussed. Although this system has been designed for use as the controller for real-time rotorcraft dynamics and control studies in a wind tunnel environment, the controller architecture can generally be applied to a wide range of automatic control applications.

Jacklin, S. A.

Adaptive inverse control for helicopter vibration reduction

The reduction or alleviation of helicopter vibration will reduce maintenance requirements while at the same time increase ride quality and helicopter reliability. In forward flight, the helicopter's fuselage vibration spectrum tends to be dominated by multiples of the N/REV component. A way to use the method of adaptive inverse control to identify, in real-time, a controller capable of generating N/REV vibration of opposite phase to cancel the uncontrolled N/REV component is presented. Multicyclic feathering of blade pitch is the control considered.

Jacklin, S. A.