Filters








6 Hits in 4.3 sec

A precise positioning actuator based on feedback-controlled magnetic shape memory alloys

Leonardo Riccardi, David Naso, Hartmut Janocha, Biagio Turchiano
2012 Mechatronics (Oxford)  
The performance of an adaptive hysteresis compensator based on the Preisach-like Krasnosel'skii-Pokrovskii model is analyzed and evaluated in the presence of temperature changes.  ...  Experiments confirm that the undesirable effects of temperature on the precision of the device can be partially addressed with an adaptive model-based algorithm devised to cope with time-varying nonlinearities  ...  KP K ðnÞ T is the vector of the state of each hysteron at time n, and v ¼ ½ v 1 v 2 . . . v K T is the vector of the weights.  ... 
doi:10.1016/j.mechatronics.2011.12.004 fatcat:gbhftaseknbdxdae5c5mv6vxem

Feedforward Controller of Ill-Conditioned Hysteresis Using Singularity-Free Prandtl–Ishlinskii Model

U-Xuan Tan, Win Tun Latt, Cheng Yap Shee, C.N. Riviere, Wei Tech Ang
2009 IEEE/ASME transactions on mechatronics  
An inevitable tradeoff between modeling accuracy and inversion stability exists. The hysteretic modeling improves with increasing number of play operators.  ...  The inverse weights are then evaluated to determine the inverse hysteresis model for the feedforward controller. For illustration purpose, a piezoelectric actuator is used.  ...  The inverse PI model can be computed easily too. In this singularity-free PI model, the formulas formed are based on one assumption.  ... 
doi:10.1109/tmech.2008.2009936 pmid:19936032 pmcid:PMC2778866 fatcat:qg5o7iiysvea7k2df4e3bddf7i

Modeling and Control of Piezoelectric Actuators for Active Physiological Tremor Compensation [chapter]

U-Xuan Tan, Win Tun, Cheng Yap, Cameron Riviere, Wei Tech
2007 Human Robot Interaction  
Some proposed incorporating inverse hysteresis model with a controller while others proposed advance controllers like neural network [Hwang et al. 2003 ], fuzzy logic [Stepanenko et al. 1998 ], sliding  ...  The rate-independent controller is based on the modified PI hysteresis model identified at the same 10Hz, 12.5 µm p-p sinusoid.  ...  It is neither possible nor is it our intention to cover every important work in this important research field in one volume.  ... 
doi:10.5772/5203 fatcat:2tciyz4uxjalhexgnc7kae4x2y

A Methodology Towards Comprehensive Evaluation of Shape Memory Alloy Actuators for Prosthetic Finger Design

Kevin O'Toole
2011
As a result, the search is on-going to find a more appropriate actuation solution that is lightweight, noiseless, strong and cheap.  ...  Instead, these control strategies are derived using iterative numerical methods such as neural networks or fuzzy models based on the experience of the researcher.  ...  The group have also developed variations on this theme by introducing a fuzzy based inverse Preisach model to reduce modelling inaccuracies, and a fuzzy based PID tuning rule-base [113] .  ... 
doi:10.21427/d71c8b fatcat:pnkddbhuandkhi6xq2yhipy5jq

Hysteresis modelling of high temperature superconductors

Mårten Sjöström
2005
Le modèle d'état critique est un modèle macroscopique connu qui décrit bien cette pénétration partielle du flux.  ...  The present dissertation considers the capabilities, limitations and possible extensions of modelling the hysteresis that is exhibited by type-II superconductors, especially those with high critical temperature  ...  They introduced feed forward neural networks instead of more classical functions in order to compute the hysteretic output.  ... 
doi:10.5075/epfl-thesis-2372 fatcat:xtbs7gojpvai5gapgrgmr2lqei

Ziolkowski_columbia_0054D_15675.pdf [article]

2019
critique but also on the identification and working through such Schärfe-one example of an iterative procedure, engendering the texture of citation across Cassirer's oeuvre.  ...  before World War One and arrives at eine sehr erstaunte Unruhe-neural pathways begin to develop from an event and are severed before arriving at an operable receptor.  ... 
doi:10.7916/d8-2jgr-ec38 fatcat:d6lvfbaltnaqdd2al2voolf4ui