Designing actuation systems for animatronic figures via globally optimal discrete search

AbstractIn the last years, Control Moment Gyros (CMGs) are widely used for high-speed attitude control, since they are able to generate larger torque compared to “classical” actuation systems, such as Reaction Wheels . This paper describes the attitude control problem of a spacecraft, using a Model Predictive Control method. The features of the considered linear MPC are: (i) a virtual reference, to guarantee input constraints satisfaction, and (ii) an integrator state as a servo compensator, to reduce the steady-state error. Moreover, the real-time implementability is investigated using an experimental testbed with four CMGs in pyramidal configuration, where the capability of attitude control and the optimization solver for embedded systems are focused on. The effectiveness and the performance of the control system are shown in both simulations and experiments.

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Conceptual Design of Electromechanical Actuation Systems for Large-Sized Directional Control Valves

Actuators ◽

10.3390/act10060133 ◽

2021 ◽

Vol 10 (6) ◽

pp. 133

Author(s):

Tobias Vonderbank ◽

Katharina Schmitz

Keyword(s):

Conceptual Design ◽

Design Process ◽

Operating Conditions ◽

Function Structure ◽

Advantages And Disadvantages ◽

Conceptual Designs ◽

Actuation Systems ◽

Electromechanical Actuation ◽

Function Structures ◽

Valve Actuation

Increasing performance in modern hydraulics is achieved by a close investigation of possible enhancements of its components. Prior research has pointed out that electromechanical actuators can form suitable alternatives to hydraulically piloted control systems. Since the requirements at these actuation systems depend on the operating conditions of the system, each actuator can be optimized to the respective hydraulic system. Considering that many different conceptual designs are suitable, the phase of conceptual design plays a decisive role during the design process. Therefore, this paper focuses on the process of developing new conceptual designs for electromechanical valve actuation systems using the method of function structures. Aiming to identify special design features, which need to be considered during the design process of electromechanical actuation systems, an exemplary actuator was designed based on the derived function structure. To highlight the potential of function structures for the development of new electromechanical valve actuation systems, two principal concepts, which allow the reduction of the necessary forces, have been developed by extending the function structure. These concepts have been experimentally investigated to identify their advantages and disadvantages.

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Model Predictive Control with Memory-based Discrete Search for Switched Linear Systems

IFAC-PapersOnLine ◽

10.1016/j.ifacol.2020.12.325 ◽

2020 ◽

Vol 53 (2) ◽

pp. 6769-6774

Author(s):

Rie B. Larsen ◽

Bilge Atasoy ◽

Rudy R. Negenborn

Keyword(s):

Model Predictive Control ◽

Linear Systems ◽

Predictive Control ◽

Switched Linear Systems ◽

Discrete Search ◽

With Memory

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Continuous and discrete search for one of many objects

Operations Research Letters ◽

10.1016/0167-6377(87)90050-2 ◽

1987 ◽

Vol 6 (5) ◽

pp. 205-209 ◽

Cited By ~ 11

Author(s):

David Assaf ◽

Shmuel Zamir

Keyword(s):

Discrete Search

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Discrete search problem in pattern recognition (Corresp.)

IEEE Transactions on Information Theory ◽

10.1109/tit.1966.1053850 ◽

1966 ◽

Vol 12 (1) ◽

pp. 69-70

Author(s):

T. Saaty

Keyword(s):

Pattern Recognition ◽

Search Problem ◽

Discrete Search

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Design, modeling, and analysis of wedge-based actuator with application to clutch-to-clutch shift

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407017727178 ◽

2017 ◽

Vol 232 (9) ◽

pp. 1149-1166

Author(s):

Fengyu Liu ◽

Li Chen ◽

Jian Yao ◽

Chunhao Lee ◽

Chi-kuan Kao ◽

...

Keyword(s):

Dynamic Models ◽

Fast Response ◽

Physical Structure ◽

Modeling And Analysis ◽

Shift Quality ◽

Actuation System ◽

Automatic Transmissions ◽

Potential Alternative ◽

Low Efficiency ◽

Actuation Systems

Clutch-to-clutch shift technology is a key enabler for fast and smooth gear shift process for multi gear transmissions. However, conventional hydraulic actuation systems for clutches have drawbacks of low efficiency, oil leakage and inadequate robustness. Electromechanical devices offer potential alternative actuators. In this paper, a novel motor driven wedge-based clutch actuator, featuring self-reinforcement, is proposed. The design concept and physical structure are thoroughly described. Dynamic models for the actuation system and vehicle powertrain are validated by experiments. Upshift and downshift processes at different engine throttle openings, clutch clearances and friction coefficients are discussed. The results show that, the self-reinforcement ratio is tested as 9.6; at the same time, the shift quality is comparable to that of the conventional hydraulic actuated clutch in automatic transmissions in terms of the shift duration (about 1 s) and vehicle jerk (<10 m/s3). Taking advantage of fast response of the actuation DC motor, the wedge-based actuator is robust dealing with uncertain clutch clearance and friction coefficient. Therefore, the wedge-based clutch actuator has potential to provide acceptable performance for clutch-to-clutch shift.

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