Abstract：
:Motion control of musculoskeletal systems for functional electrical stimulation (FES) is a challenging problem due to the inherent complexity of the systems. These include being highly nonlinear, strongly coupled, time-varying, time-delayed, and redundant. The redundancy in particular makes it difficult to find an inverse model of the system for control purposes. We have developed a control system for multiple input multiple output (MIMO) redundant musculoskeletal systems with little prior information. The proposed method separates the steady-state properties from the dynamic properties. The dynamic control uses a steady-state inverse model and is implemented with both a PID controller for disturbance rejection and an artificial neural network (ANN) feedforward controller for fast trajectory tracking. A mechanism to control the sum of the muscle excitation levels is also included. To test the performance of the proposed control system, a two degree of freedom ankle-subtalar joint model with eight muscles was used. The simulation results show that separation of steady-state and dynamic control allow small output tracking errors for different reference trajectories such as pseudo-step, sinusoidal and filtered random signals. The proposed control method also demonstrated robustness against system parameter and controller parameter variations. A possible application of this control algorithm is FES control using multiple contact cuff electrodes where mathematical modeling is not feasible and the redundancy makes the control of dynamic movement difficult.
journal_name
Biol Cybernjournal_title
Biological cyberneticsauthors
Park H,Durand DMdoi
10.1007/s00422-008-0258-5subject
Has Abstractpub_date
2008-12-01 00:00:00pages
503-16issue
6eissn
0340-1200issn
1432-0770journal_volume
99pub_type
杂志文章abstract：:A mathematical model for describing dynamic phenomena in the olfactory bulb is presented. The nature of attractors and the bifurcation sequences in terms of the lateral connection strength in the mitral layer are studied numerically. Chaotic activity has only been found in the case of strong excitatory coupling. Synap...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00201408
更新日期：1993-01-01 00:00:00
abstract：:In this article, we present a neurologically motivated computational architecture for visual information processing. The computational architecture's focus lies in multiple strategies: hierarchical processing, parallel and concurrent processing, and modularity. The architecture is modular and expandable in both hardwa...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-014-0597-3
更新日期：2014-06-01 00:00:00
abstract：:It is well known that the human postural control system responds to motion of the visual scene, but the implicit assumptions it makes about the visual environment and what quantities, if any, it estimates about the visual environment are unknown. This study compares the behavior of four models of the human postural co...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-004-0535-x
更新日期：2005-03-01 00:00:00
abstract：:We present a controls systems model of horizontal-plane head movements during perturbations of the trunk, which for the first time interfaces a model of the human head with neural feedback controllers representing the vestibulocollic (VCR) and the cervicocollic (CCR) reflexes. This model is homeomorphic such that mode...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050297
更新日期：1996-10-01 00:00:00
abstract：:Histograms of fast-phase intervals in human optokinetic and vestibular nystagmus were generated, and fitted to statistical distributions used in previous studies. The distributions did not depend on stimulation type (optokinetic or vestibular). An inverse Gaussian or a gamma distribution fitted the data better than di...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-002-0324-3
更新日期：2002-07-01 00:00:00
abstract：:Learning to make reaching movements in force fields was used as a paradigm to explore the system architecture of the biological adaptive controller. We compared the performance of a number of candidate control systems that acted on a model of the neuromuscular system of the human arm and asked how well the dynamics of...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050543
更新日期：1999-07-01 00:00:00
abstract：:Multiplying memory span by mental speed, we obtain the information entropy of short-term memory capacity, which is rate-limiting for cognitive functions and corresponds with EEG power spectral density. The number of EEG harmonics (n = 1, 2,..., 9) is identical with memory span, and the eigenvalues of the EEG impulse r...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00201438
更新日期：1992-01-01 00:00:00
abstract：:We consider a simple electronic circuit model of a single neuron. The neuron is assumed to be driven by an external signal comprising constant (dc) and random components. In addition, the nonlinearity parameter in the circuit is assumed to fluctuate, thereby giving rise to critical behavior including the onset of hyst...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00198768
更新日期：1989-01-01 00:00:00
abstract：:The relationship between disparity and ocular vergence was investigated under closed-loop as well as under open-loop viewing conditions. First we examined whether vergence responded similarly to disparity presented under open-loop and closed-loop conditions. Similar response were observed in both conditions. The direc...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00224855
更新日期：1993-01-01 00:00:00
abstract：:In the context of the models of structure from motion visual processing, we propose that the optic-flow field is a source of information for the perception of the curvature of a smooth surface in motion. In particular, it is shown how the spin variation (SV), a second spatial derivative of the retinal velocity field, ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00198096
更新日期：1990-01-01 00:00:00
abstract：:In the first part of lifting movements, the trunk movement is surprisingly resistant to perturbations. This study examined which factors contribute to this perturbation resistance of the trunk during lifting. Three possible mechanisms were studied: force-length-velocity characteristics of muscles, the momentum of the ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-005-0583-x
更新日期：2005-07-01 00:00:00
abstract：:Nonlinear oscillators are usually utilized by bionic scientists for establishing central pattern generator models for imitating rhythmic motions by bionic scientists. In the natural word, many rhythmic motions possess asymmetric time ratios, which means that the forward and the backward motions of an oscillating proce...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-018-0746-1
更新日期：2018-06-01 00:00:00
abstract：:There are two issues in balancing a stick pivoting on a finger tip (or mechanically on a moving cart): maintaining the stick angle near to vertical and maintaining the horizontal position within the bounds of reach or cart track. The (linearised) dynamics of the angle are second order (although driven by pivot acceler...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-013-0564-4
更新日期：2013-12-01 00:00:00
abstract：:In motion-processing areas of the visual cortex in cats and monkeys, an anisotropic distribution of direction selectivities displays a preference for movements away from the fovea. This 'centrifugal bias' has been hypothetically linked to the processing of optic flow fields generated during forward locomotion. In this...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00201489
更新日期：1995-01-01 00:00:00
abstract：:This paper deals with characterization and modelling of human handwriting motion from two forearm muscle activity signals, called electromyography signals (EMG). In this work, an experimental approach was used to record the coordinates of a pen tip moving on the (x, y) plane and EMG signals during the handwriting act....
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-015-0670-6
更新日期：2016-02-01 00:00:00
abstract：:This study is concerned with synaptic reorganization in local neuronal networks. Within networks of 30 neurons, an initial disequilibrium in connectivity has to be compensated by reorganization of synapses. Such plasticity is not a genetically determined process, but depends on results of neuronal interaction. Neurobi...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00364134
更新日期：1988-01-01 00:00:00
abstract：:Most common motor acts involve highly redundant effector systems. Understanding how such systems are controlled by the nervous system is a long-standing scientific challenge. Most proposals for solving this problem are based on the assumption that a particular solution, which optimizes additional constraints, is selec...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220100279
更新日期：2002-01-01 00:00:00
abstract：:A mathematical muscle model is presented that relates neural control signals linearly to muscle force without violating important known physiological constraints, such as the size-principle (Henneman and Mendell 1981) and non-linear twitch summation (Burke et al. 1976). This linearity implies that the neural control s...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00206220
更新日期：1991-01-01 00:00:00
abstract：:This paper presents a model for the circadian temporization system of mammals which associates the synchronization dynamics of coupling oscillators to a set of equations able to reproduce the synaptic characteristics of somatodendritic membrane of neurons. The circadian timing system is organized in a way to receive i...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-009-0309-6
更新日期：2009-05-01 00:00:00
abstract：:Rotations of the eye are generated by the torques that the eye muscles apply to the eye. The relationship between eye orientation and the direction of the torques generated by the extraocular muscles is therefore central to any understanding of the control of three-dimensional eye movements of any type. We review the ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-004-0477-3
更新日期：2004-06-01 00:00:00
abstract：:The trace version of classical conditioning is used as a prototypical hippocampal-dependent task to study the recoding sequence prediction theory of hippocampal function. This theory conjectures that the hippocampus is a random recoder of sequences and that, once formed, the neuronal codes are suitable for prediction....
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-005-0568-9
更新日期：2005-06-01 00:00:00
abstract：:Evoked potential waveforms are generally of a dynamic, transient character. Consequently, their spectral energy distribution cannot be adequately described by time-invariant representations, such as the power density spectrum. Obviously, a spectro-temporal description is needed. Appropriate means for obtaining such de...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00335365
更新日期：1981-01-01 00:00:00
abstract：:We discuss natural limitations on motor performance caused by the time delay required for feedback signals to propagate within the human body or mechanical control systems. By considering a very simple delayed linear servomechanism model, we show there exists a best possible speed-accuracy trade-off similar to Fitts' ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-008-0235-z
更新日期：2008-07-01 00:00:00
abstract：:This study is carried out on single (not averaged) recordings combining the spontaneous activity preceding the stimulus onset and the EP recorded upon acoustical stimulation. These recordings, which we call EEG-EPograms, are measured simultaneously from different subdural structures, such as the auditory cortex, media...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00336853
更新日期：1979-09-01 00:00:00
abstract：:Stable signal transmission is crucial for information processing by the brain. Synfire-chains, defined as feed-forward networks of spiking neurons, are a well-studied class of circuit structure that can propagate a packet of single spikes while maintaining a fixed packet profile. Here, we studied the stable propagatio...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-008-0246-9
更新日期：2008-08-01 00:00:00
abstract：:We study weakly connected networks of neural oscillators near multiple Andronov-Hopf bifurcation points. We analyze relationships between synaptic organizations (anatomy) of the networks and their dynamical properties (function). Our principal assumptions are: (1) Each neural oscillator comprises two populations of ne...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050279
更新日期：1996-08-01 00:00:00
abstract：:This article provides an introductory overview of the state of research on Hierarchical Bayesian Modeling in cognitive development. First, a brief historical summary and a definition of hierarchies in Bayesian modeling are given. Subsequently, some model structures are described based on four examples in the literatur...
journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/s00422-016-0686-6
更新日期：2016-06-01 00:00:00
abstract：:Two different chaotic time series analysis methods--the correlation dimension and nonlinear forecasting--are introduced and then used to process the interspike intervals (ISI) of the action potential trains propagated along a single nerve fiber of the anesthetized rat. From the results, the conclusion is drawn that co...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050422
更新日期：1998-02-01 00:00:00
abstract：:A system of coupled bistable Hopf oscillators with an external periodic input source was used to model the ability of interacting neural populations to synchronize and desynchronize in response to variations of the input signal. We propose that, in biological systems, the settings of internal and external coupling str...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050023
更新日期：2000-03-01 00:00:00
abstract：:Isolated and cultured neonatal cardiac myocytes contract spontaneously and cyclically, and have the properties of a non-linear oscillator. In this study, we have analyzed the relationship between the fluctuation of contraction rhythm of spontaneously beating cultured cardiac myocytes, and the coupling strength among t...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-001-0285-y
更新日期：2002-02-01 00:00:00
