Describing functions for nonlinear friction in relay servos
About: This article is published in IEEE Transactions on Automatic Control.The article was published on 1963-07-01. It has received 2 citations till now. The article focuses on the topics: Describing function & Relay.
Citations
More filters
TL;DR: This survey is the first to bring to the attention of the controls community the important contributions from the tribology, lubrication and physics literatures, and provides a set of models and tools for friction compensation which will be of value to both research and application engineers.
2,658 citations
Cites methods from "Describing functions for nonlinear ..."
...The early investigators (Tou and Schultheiss, 1953; Satyendra, 1956; Silverberg, 1957; Shen, 1962; Woodward, 1963) did not employ the memoryless element construction, but developed describing functions for the composite of the elements from the force input to the velocity output, as shown in Fig....
[...]
...The application of describing function analysis to study the motions of machines with friction has a long history (Tou and Schuitheiss, 1953; Satyendra, 1956; Siiverberg, 1957; Shen, 1962; Woodward, 1963; Brandenburg, 1986; Brandenburg and Schiller, 1987, 1988a, b, 1989, 1991: Sch~ifer and Brandenburg, 1990, 1993; Townsend and Salisbury, 1987; Wallenborg and ,~str/Sm, 1988; Canudas de Wit 1988; Canudas de Wit and Seront, 1990; Canudas de Wit 1987, 1991; Ehrich, 1991)....
[...]
02 Jun 1993
TL;DR: In this paper, the authors present an outline of topics literature references important for the analysis and compensation of servos with friction, including control, tribology, lubrication engineering, acoustics and general engineering and physics.
Abstract: Friction compensation is a broad area that has recently been surveyed in [3]. The survey considers over 250 references from the journals of controls, tribology, lubrication engineering, acoustics and general engineering and physics and is perhaps 20 times too large to fit in this conference paper and its companion. Rather than trating one or a few topics to the neglect of many others; this paper is composed as an outline of topics literature references important for the analysis and compensation of servos with friction.
12 citations
References
More filters
TL;DR: The analysis indicates that certain series equalizers designed from linear theory may fail to achieve effective compensation in the presence of sliding and static friction and a subsidiary loop may avoid the stability problem while still realizing an essentially equivalent loop gain function.
Abstract: One of the most common nonlinearities encountered in servomechanisms design is the friction phenomenon in electromechanical systems. Conventional linear theory fails to predict its effect upon system performance. This paper extends familiar techniques to the treatment of friction nonlinearity in servosystems. Frequency‐response methods are employed throughout and the theoretical results are verified by means of an analog computer. Sliding friction and static friction are represented by describing functions which form the critical factors in determining system stability. The analysis indicates that certain series equalizers designed from linear theory may fail to achieve effective compensation in the presence of sliding and static friction. On the other hand, a subsidiary loop may avoid the stability problem while still realizing an essentially equivalent loop gain function.
33 citations
TL;DR: In this paper, a general procedure, using frequency response techniques, is outlined for the synthesis of compensation in systems affected by coulomb friction, which is based on the recognition that a control device has a describing function which reduces gain and introduces phase lag.
Abstract: The presence of coulomb friction in servomechanisms often results in undesirable effects, such as an operating dead-zone, low-frequency wander, and poor dynamic performance for low level signals. Methods of compensation for these adverse effects are discussed and a specific example is presented. Also, a general procedure, using frequency-response techniques, is outlined for the synthesis of compensation in systems affected by coulomb friction. The methods employed are based on the recognition that coulomb friction in a control device has a describing function which reduces gain and introduces phase lag. The describing function is determined by both the amplitude and the frequency of the input signal to the device.
13 citations
TL;DR: In this paper, the possiblity of utilizing coulomb friction present in relay servo systems for the purpose of improving their small-signal stability is investigated and discussed on the basis of describing function results and data obtained with the help of a simulator are also presented as an experimental aid to the understanding of the system operation.
Abstract: The paper gives results of investigations made on the possiblity of utilizing coulomb friction present in relay servo systems for the purpose of improving their small-signal stability. Discussions are presented on the basis of describing function results. Data obtained with the help of a simulator are also presented as an experimental aid to the understanding of the system operation.
2 citations