1. Introduction. 2. Linear Algebra. 3. Linear Systems. 4. H2 and Ha Spaces. 5. Internal Stability. 6. Performance Specifications and Limitations. 7. Balanced Model Reduction. 8. Uncertainty and Robustness. 9. Linear Fractional Transformation. 10. m and m- Synthesis. 11. Controller Parameterization. 12. Algebraic Riccati Equations. 13. H2 Optimal Control. 14. Ha Control. 15. Controller Reduction. 16. Ha Loop Shaping. 17. Gap Metric and ...u- Gap Metric. 18. Miscellaneous Topics. Bibliography. Index.

/pdf/essentials-of-robust-control-3kaks6yk3h.pdf

Essentials of Robust Control

Electrical energy storage technologies for stationary applications are reviewed. Particular attention is paid to pumped hydroelectric storage, compressed air energy storage, battery, flow battery, fuel cell, solar fuel, superconducting magnetic energy storage, flywheel, capacitor/supercapacitor, and thermal energy storage. Comparison is made among these technologies in terms of technical characteristics, applications and deployment status.

http://promexico.me/Rubenius/WhitePapers/sdarticle%20(1).pdf

Progress in electrical energy storage system: A critical review

This article surveyed the major results in iterative learning control (ILC) analysis and design over the past two decades. Problems in stability, performance, learning transient behavior, and robustness were discussed along with four design techniques that have emerged as among the most popular. The content of this survey was selected to provide the reader with a broad perspective of the important ideas, potential, and limitations of ILC. Indeed, the maturing field of ILC includes many results and learning algorithms beyond the scope of this survey. Though beginning its third decade of active research, the field of ILC shows no sign of slowing down.

A survey of iterative learning control

Pedestrians follow different trajectories to avoid obstacles and accommodate fellow pedestrians. Any autonomous vehicle navigating such a scene should be able to foresee the future positions of pedestrians and accordingly adjust its path to avoid collisions. This problem of trajectory prediction can be viewed as a sequence generation task, where we are interested in predicting the future trajectory of people based on their past positions. Following the recent success of Recurrent Neural Network (RNN) models for sequence prediction tasks, we propose an LSTM model which can learn general human movement and predict their future trajectories. This is in contrast to traditional approaches which use hand-crafted functions such as Social forces. We demonstrate the performance of our method on several public datasets. Our model outperforms state-of-the-art methods on some of these datasets. We also analyze the trajectories predicted by our model to demonstrate the motion behaviour learned by our model.

/pdf/social-lstm-human-trajectory-prediction-in-crowded-spaces-wwxok9svq7.pdf

Social LSTM: Human Trajectory Prediction in Crowded Spaces

Reinforcement learning offers to robotics a framework and set of tools for the design of sophisticated and hard-to-engineer behaviors. Conversely, the challenges of robotic problems provide both inspiration, impact, and validation for developments in reinforcement learning. The relationship between disciplines has sufficient promise to be likened to that between physics and mathematics. In this article, we attempt to strengthen the links between the two research communities by providing a survey of work in reinforcement learning for behavior generation in robots. We highlight both key challenges in robot reinforcement learning as well as notable successes. We discuss how contributions tamed the complexity of the domain and study the role of algorithms, representations, and prior knowledge in achieving these successes. As a result, a particular focus of our paper lies on the choice between model-based and model-free as well as between value-function-based and policy-search methods. By analyzing a simple problem in some detail we demonstrate how reinforcement learning approaches may be profitably applied, and we note throughout open questions and the tremendous potential for future research.

/pdf/reinforcement-learning-in-robotics-a-survey-4w4397qx9i.pdf

Reinforcement learning in robotics: A survey

In a collaboration of the Technische Universiteit Eindhoven, Delft University of Technology and TNO Science and Industry a new adaptive deformable mirror (DM) is being developed. The deformable mirror will be used in large telescope systems to correct both the temporal and spatial high frequent distortions in the optical wavefront caused by atmospheric turbulence.The DM consists of a thin continuous membrane which acts as the correcting element. A grid of low voltage electro-magnetical push-pull actuators, - located in an actuator plate -, impose out-of-plane displacements in the mirror’s membrane. In the design variable reluctance actuators are used. These consist of a closed magnetic circuit in which a strong permanent magnet provides a static magnetic force on a ferromagnetic core which is suspended in a membrane. By applying a current through the coil which is situated around the magnet, this force is influenced, providing movement of the core. This movement is transferred via a rod imposing the out-of-plane displacements in the reflective deformable membrane. In the actuator design a match is made between the negative stiffness of the magnet and the positive stiffness of the membrane suspension. If the locality of the influence functions, mirror modes, force and power dissipation are taken into account, a resonance frequency of 1500 Hz and an overall stiffness of 1000 N/m for the actuators is needed. The dynamic response of the first actuators is tested in a dedicated setup. It shows an eigen frequency of 950 Hz. This is due to a lower magnetic force than expected. With a Helmholtz coil test setup the 2nd quadrant of the B-H curve is reconstructed by stacking of the magnets and using the demagnetization factor. It is shown that the values for Hc and Br of the magnets are indeed lower than the values used for the initial design. New actuators, with increased magnet thickness, are designed, fabricated and tested.Transfer functions are made with different dc offsets of the actuator. From these transfer functions, characteristics as resonance frequencies, force, stiffness, motor constant, current and dissipation and efficiency all as function of the stroke of the actuator have been adopted. These experimental results are compared with the theoretic predictions. The results are in good agreement.Grids with 61 actuators are made including the dedicated drive electronics. The module is the standard building block from which large arrays are assembled.

http://www.mate.tue.nl/mate/pdfs/7807.pdf

Actuator grid design for an adaptive deformable mirror

The NANOMEFOS non-contact measurement machine for freeform optics has been completed. The separate short metrology loop results in a stability at standstill of 0.9 nm rms over 0.1 s. Measurements of a tilted flat show a repeatability of 2-4 nm rms, depending on the applied tilt, and a flatness that agrees well with the NMi measurement.

/pdf/freeform-optics-measurements-with-the-nanomefos-non-contact-4tggvvg2nx.pdf

Freeform optics measurements with the NANOMEFOS non-contact measurement machine

Recent results on the control of linear systems subject to time-domain constraints could only handle the case of closed-loop poles that are situated on the real axis. As most closed-loop systems in practice contain also complex poles, there is a strong need for a general framework encompassing all cases. In this paper such a framework is presented based on sums-of-squares techniques and we show indeed that time-domain constraints on closed-loop signals of linear systems can be incorporated as linear matrix inequalities, even when complex conjugate poles are assigned. The effectiveness of this complete design method is evaluated by means of a simulation example.

/pdf/linear-control-of-time-domain-constrained-systems-tpntylalit.pdf

Linear control of time-domain constrained systems

The design of robust controllers for a compact disc mechanism is considered. Using mu synthesis, a controller has been designed for good track-following. The design problem involves time-domain constraints on signals and robustness requirements for norm-bounded structured plant uncertainty. It is shown that by using weighting functions in the mu framework this problem can be solved, but at the cost of many design iterations. The mu controller has been implemented in an experimental setup with a digitally controlled compact disc player.<<ETX>>

Robust control of a Compact Disc player.

Purpose:Robotics have enhanced and refined microinvasive surgery in several disciplines. Its applicability in eye surgery has been limited by ergonomic and scaling issues. Our aim was to design and build a microrobotic system adapted to the needs of vitreoretinal surgeons. Methods:Constraints regarding head positioning and size, ocular access, surgical execution, and procedural requirements were defined by observations at live surgeries, discussions with surgeons, operation room teams, and computer simulations. Additional design parameters for the robotic slave (RS) included a low weight, high stiffness, low friction and play-free design. For the control module (CM), intuitiveness of the controller, body posture of the operator and patient proximity were considered. Results:The RS consists of at least two instrument manipulators (IMs).The IM’s design allows 5 degrees of freedom through a kinematically defined rotation point at the entry site into the sclera. Force measurement down to 10mN is possible and manipulation with an accuracy of

/pdf/design-of-a-compact-robotic-assisted-ophthalmic-system-2tr9a547tn.pdf

M Maarten Steinbuch

Papers

Actuator grid design for an adaptive deformable mirror

Freeform optics measurements with the NANOMEFOS non-contact measurement machine

Linear control of time-domain constrained systems

Robust control of a Compact Disc player.

Design of a compact robotic assisted ophthalmic system