scholarly journals The man-machine analogy in robotics and neurophysiology

2002 ◽  
Vol 12 (1) ◽  
pp. 4-8 ◽  
Author(s):  
Arthur Prochazka
Keyword(s):  
Control Systems ◽  
Neural Control ◽  
Knee Prosthesis ◽  
Neural Nets ◽  
State Transitions ◽  
Step Cycle ◽  
Logic Control ◽  
Finite State ◽  
New Type ◽  
Robotic Devices

Since the time of Descartes the machine-like control of movement in animals and the animal-like control of movement in automata has fascinated and inspired scientists, engineers and philosophers alike. In 1966, Drs. Rajko Tomovic and Robert McGhee proposed the concept of a "cybernetic actuator," a new type of control system which "possesses the property of producing continuous controlled motion from an input which may assume only four distinct states". The specific application at the time was an artificial limb prosthesis. Signals from sensors monitoring joint angle and ground contact were to be continuously compared to a set of threshold values corresponding to specific moments in the step cycle. The binary signals (above or below threshold) were listed in a look-up chart which associated sensory combinations with actuator states. It was proposed that this system would provide all of the known state transitions required of an above knee prosthesis. In this and later papers Tomovic was careful to point out the differences between such "artificial reflex control" systems and neural control systems in animals. Nonetheless in the last few years it has become commonplace to see the control of locomotion and other rhythmical behaviors described in terms of "sensory rules," that is in terms of finite state systems. With the advent of neural nets and fuzzy logic control robotic devices are taking on more and more of the features of biological control systems. In turn, neurophysiologists borrow more and more from the concepts and mechanisms of modern control theory. The influence of Tomovic's simple but powerful idea continues to spread.

Control Electronics and Hybrid Dynamic System-Based API for a 6-DOF Desktop Haptic Interface

1999 ◽  
Author(s):  
S. E. Salcudean ◽  
R. Six ◽  
R. Barman ◽  
S. Kingdon ◽  
I. Chau ◽  
...  
Keyword(s):  
Dynamic System ◽  
Haptic Interface ◽  
State Transitions ◽  
Hybrid Dynamic System ◽  
Finite State ◽  
Control Electronics ◽  
Six Degree Of Freedom ◽  
Electronic Hardware ◽  
Device Location ◽  
Programming Interface

Abstract A six-degree-of-freedom desktop magnetically levitated haptic interface has been developed by the authors. Its electromechanical design is described in (Salcudean and Parker, 1997). In this paper, aspects of electronic hardware architecture and the control of actuator currents are discussed. To program this device, a new low level applications programming interface (API) that models the haptic interface as a hybrid dynamic system is proposed. The user can define a finite state machine in which every state is a device impedance. State transitions occur upon the satisfaction of linear inequalities in terms of the device location, velocity and force. Examples of the use of such hybrid dynamic systems to produce haptic effects are given.

A systematic method for design of multivariable fuzzy logic control systems

1999 ◽  
Vol 7 (6) ◽  
pp. 741-752 ◽  
Author(s):  
Zong-Mu Yeh
Keyword(s):  
Fuzzy Logic ◽  
Control Systems ◽  
Fuzzy Logic Control ◽  
Systematic Method ◽  
Logic Control

scholarly journals A unicellular walker embodies a finite state machine

2021 ◽  
Author(s):  
Ben T. Larson ◽  
Jack Garbus ◽  
Jordan B. Pollack ◽  
Wallace F. Marshall
Keyword(s):  
Cell Biology ◽  
General Framework ◽  
Finite State Machine ◽  
Detailed Balance ◽  
State Machine ◽  
Theoretical Computer Science ◽  
State Transitions ◽  
Small Subset ◽  
Finite State ◽  
Computational Processes

Cells are complex biochemical systems whose behavior emerges from interactions among myriad molecular components. The idea that cells execute computational processes is often invoked as a general framework for understanding cellular complexity. However, the manner in which cells might embody computational processes in a way that the powerful theories of computation, such as finite state machine models, could be productively applied, remains to be seen. Here we demonstrate finite state machine-like processing embodied in cells, using the walking behavior of Euplotes eurystomus, a ciliate that walks across surfaces using fourteen motile appendages called cirri. We found that cellular walking entails a discrete set of gait states. Transitions between these states are highly regulated, with distinct breaking of detailed balance and only a small subset of possible transitions actually observed. The set of observed transitions decomposes into a small group of high-probability unbalanced transitions forming a cycle and a large group of low-probability balanced transitions, thus revealing stereotypy in sequential patterns of state transitions. Taken together these findings implicate a machine-like process. Cirri are connected by microtubule bundles, and we find an association between the involvement of cirri in different state transitions and the pattern of attachment to the microtubule bundle system, suggesting a mechanical basis for the regularity of state transitions. We propose a model where the actively controlled, unbalanced transitions establish strain in certain cirri, the release of which from the substrate causes the cell to advance forward along a linear trajectory. This demonstration of a finite state machine embodied in a living cell opens up new links between theoretical computer science and cell biology and may provide a general framework for understanding and predicting cell behavior at a super-molecular level.

scholarly journals Environmentally friendly method for regeneration of copper chloride acidic solutions used in etching of printed circuits

2017 ◽  
Vol 18 ◽  
pp. 01021
Author(s):  
Dorota Kopyto ◽  
Wit Baranek ◽  
Zbigniew Myczkowski ◽  
Katarzyna Leszczyńska-Sejda ◽  
Michał Drzazga ◽  
...  
Keyword(s):  
Control Systems ◽  
Copper Chloride ◽  
Environmentally Friendly ◽  
Acidic Solutions ◽  
Printed Circuits ◽  
Innovative Method ◽  
Reactor Construction ◽  
New Type ◽  
Oxygen Utilisation ◽  
Environmentally Friendly Method

Etching of copper with acidic CuCl2 solution is a widely used chemical method in printed circuits production. During the process, the solution is enriched in Cu(I) ions, resulting in reduction and then loss of etching bath capacity. In order to ensure the required etching kinetics, the solution is regenerated by oxidation of Cu(I) to Cu(II). The industrially applied Cu(I) oxidants are, e.g.: Cl2, chlorates. Their application is expensive and associated with drawbacks related to health, safety and environmental hazards (e.g. Cl2 emission). In the result of long-standing cooperation between the IMN and MATUSEWICZ Budowa Maszyn, an innovative, original and environmentally friendly method of acidic solutions regeneration used during printed circuits etching was developed. A new-type reactor equipped with oxidation monitoring-control systems using oxygen or oxygen-enriched air was applied. The reactor construction enables to run the process with oxygen circulation in the reactor, ensures full oxygen utilisation in the regeneration process, achievement of the required performance and process rate, and eliminates expensive, hazardous and often toxic reagents. This is an innovative method, and since there are no analogous technologies currently known and used in Europe and worldwide, the presented method is technologically, economically and ecologically unrivalled.

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