Lidé

doc. Ing. Tomáš Haniš, Ph.D.

Všechny publikace

Real-time estimation of the optimal longitudinal slip ratio for attaining the maximum traction force

  • DOI: 10.1016/j.conengprac.2024.105876
  • Odkaz: https://doi.org/10.1016/j.conengprac.2024.105876
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Advanced driver assistant systems in vehicles, such as anti-lock brake system, electronic stability program, and traction control, heavily rely on the traction force of the wheels, which is determined by the wheels’ longitudinal slip ratio. A common method used to describe this dependency is the well-known Pacejka (magic) formula. The Pacejka (magic) formula suggests the existence of a unique optimal slip ratio, denoted as lambda_opt, for which the maximum traction force is achieved. Although the lambda_opt value slightly varies with changes in the tire-to-road interface, most studies tend to neglect the variation of lambda_opt due to its relatively low impact on the introduced error. Instead, most studies focus on estimating the maximum friction coefficient mu_max . In this paper, we address this oversimplification and propose an estimation method for lambda_opt. This paper introduces two novel approaches for real-time estimation of the slip ratio lambda_opt based on wheel dynamics. Both approaches were derived using a nonlinear twin-track model implemented in MATLAB & Simulink. The first approach uses recursive least squares, whereas the second approach employs the Unscented Kalman filter algorithm. In addition, a traction force estimator is presented because both estimators rely on either a measurement or an estimation of the traction force. To validate the performance of the proposed estimators, a high-fidelity twin-track vehicle model was initially employed. Finally, real-world experiments are presented in which the proposed algorithms are validated using an RC subscale platform.

Brake Control Allocation Employing Vehicle Motion Feedback for Four-Wheel-Independent-Drive Vehicle

  • Autoři: Vošahlík, D., Veselý, T., doc. Ing. Tomáš Haniš, Ph.D., Pekar, J.
  • Publikace: SAE Technical Papers. Warrendale, PA: SAE International, 2023. ISSN 0148-7191.
  • Rok: 2023
  • DOI: 10.4271/2023-01-1866
  • Odkaz: https://doi.org/10.4271/2023-01-1866
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    This paper uses the brake control allocation method for Electric Vehicles (EVs) based on system-level vehicle Reference Point (RP) motion feedback. The RP motion control is an alternative to the standard brake torque allocation methods and results in improved vehicle stability in both longitudinal and lateral directions without requiring additional measurements beyond what is available in EVs with ABS and ESP. The proposed control law simplifies the brake torque allocation algorithm, reduces overall development time and effort, and merges most of the braking systems into one. Additionally, the measured or estimated signals required are reduced compared to the standard approach. The system-level RP measurements and references are transformed into individual wheel coordinate systems, where tracking is ensured by actuating both friction torques and electric motor regenerative torques using a proposed brake torque blending mechanism. The whole control system is validated in simulations using the Simulink vehicle dynamic simulator and IPG Carmaker high-fidelity simulator, utilizing the CTU FEE EFORCE formula model. Finally, a brake HiL stand validation is presented.

Traction Control Allocation Employing Vehicle Motion Feedback Controller for Four-Wheel-Independent-Drive Vehicle

  • Autoři: Vošahlík, D., doc. Ing. Tomáš Haniš, Ph.D.,
  • Publikace: IEEE Transactions on Intelligent Transportation Systems. 2023, 24(12), 14570-14579. ISSN 1524-9050.
  • Rok: 2023
  • DOI: 10.1109/TITS.2023.3295436
  • Odkaz: https://doi.org/10.1109/TITS.2023.3295436
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    A novel vehicle traction algorithm solving the traction force allocation problem based on vehicle center point motion feedback controller is proposed in this paper. The center point motion feedback control system proposed utilizes individual wheel torque actuation assuming all wheels are individually driven. The approach presented is an alternative to the various direct optimization-based traction force/torque allocation schemes. The proposed system has many benefits, such as significant reduction of the algorithm complexity by merging most traction system functionalities into one. Such a system enables significant simplification, unification, and standardization of powertrain control design. Moreover, many signals needed by conventional traction force allocation methods are not required to be measured or estimated with the proposed approach, which are among others vehicle mass, wheel loading (normal force), and vehicle center of gravity location. Vehicle center point trajectory setpoints and measurements are transformed to each wheel, where the tracking is ensured using the wheel torque actuation. The proposed control architecture performance and analysis are shown using the nonlinear twin-track vehicle model implemented in Matlab & Simulink environment. The performance is then validated using high fidelity FEE CTU in Prague EFORCE formula model implemented in IPG CarMaker environment with selected test scenarios. Finally, the results of the proposed control allocation are compared to the state-of-the-art approach.

Vehicle Dynamics Trajectory Planning: Minimum Violation Planning Modifications Reducing Computational Time

  • Autoři: Vošahlík, D., Turnovec, P., Pekař, J., Boháč, M., doc. Ing. Tomáš Haniš, Ph.D.,
  • Publikace: 2023 SICE International Symposium on Control Systems. Piscataway: IEEE, 2023. p. 27-32. ISBN 978-4-907764-76-0.
  • Rok: 2023
  • DOI: 10.23919/SICEISCS57194.2023.10079204
  • Odkaz: https://doi.org/10.23919/SICEISCS57194.2023.10079204
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    State trajectory planning is recently one of the main challenges for self driving/autonomous vehicles technology. The Minimum Violation Planing (MVP) approach provides a reliable and user intuitive framework for states trajectory planning. It provides possibility of various logic constraints, boundary conditions, dynamic constraints, and many others. The MVP is revisited in this paper with a special focus on the time efficiency of the algorithm. Two modifications of the MVP reducing the calculation time while not significantly compromising the trajectory quality are proposed in this paper. The vehicle yaw, yaw rate, north and east position, velocity, and battery state of charge variables planning is selected to compare the proposed planning framework modifications. The presented modifications and the original MVP algorithm are compared in selected test scenario, where significant calculation time reduction is shown while the plan optimality is not affected remarkably

Driving Envelope: On Vehicle Stability Through Tire Capacities

  • DOI: 10.1109/IV51971.2022.9827423
  • Odkaz: https://doi.org/10.1109/IV51971.2022.9827423
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Integrated automated safety systems in vehicles significantly reduced the number of car crashes. They help the driver in critical maneuvers when tires lose their grip on the driving surface. For instance, the technology of the anti-lock braking system and its augmentations (electronic stability control and traction control system) has already saved thousands of lives. Nevertheless, we still see room for improvement. This work defines boundaries in the vehicle state-space, excluding unstable vehicle maneuvers. Such boundaries form a so-called driving envelope. The resulting set includes all states where the vehicle’s wheels are not locked, overspun, or skidding. For the definition of the driving envelope, we use the Pacejka tire model and nonlinear single-track model. This paper shows how each tire dynamic property results in vehicle dynamics. Also, it discusses the application of nonlinear and linearized driving envelope boundaries on a single-track model. Then it shows that the linearized driving envelope constraints form a close to control invariant set over the vehicle state-space. Thus, the driving envelope is almost a feasible set, and it could be used in the model predictive control approaches with soft constraints. Protecting the driving envelope, one can preserve each wheel from locking, wheelspin, and skidding.

Spatio-Temporal Decomposition of Sum-of-Squares Programs for the Region of Attraction and Reachability

  • DOI: 10.1109/LCSYS.2021.3086585
  • Odkaz: https://doi.org/10.1109/LCSYS.2021.3086585
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    This letter presents a method for calculat- ing Region of Attraction of a target set (not necessar- ily an equilibrium) for controlled polynomial dynamical systems, using a hierarchy of semidefinite programming problems (SDPs). Our approach builds on previous work and addresses its main issue, the fast-growing memory demands for solving large-scale SDPs. The main idea in this work is in dissecting the original resource-demanding problem into multiple smaller, interconnected, and easier to solve problems. This is achieved by spatio-temporal split- ting akin to methods based on partial differential equations. We show that the splitting procedure retains the conver- gence and outer-approximation guarantees of the previous work, while achieving higher precision in less time and with smaller memory footprint.

Vehicle Trajectory Planning: Minimum Violation Planning and Model Predictive Control Comparison

  • Autoři: Vošahlík, D., Turnovec, P., Pekař, J., doc. Ing. Tomáš Haniš, Ph.D.,
  • Publikace: Proceedings of 2022 IEEE Intelligent Vehicles Symposium (IV). Piscataway: IEEE, 2022. p. 145-150. ISSN 1931-0587. ISBN 978-1-6654-8821-1.
  • Rok: 2022
  • DOI: 10.1109/IV51971.2022.9827430
  • Odkaz: https://doi.org/10.1109/IV51971.2022.9827430
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    State trajectory planning is one of the primary self-driving cars technology enablers. However, state trajectory planning is a more complex and computationally demanding task compared to path planning. The vehicle’s east and north position, yaw, yaw rate, velocity, and battery state of charge variables trajectory planning with a particular focus on the safety and economy of the vehicle operation is concerned in this paper. Comparison of Model Predictive Control (MPC) and Minimum Violation Planning (MVP) used for trajectory planning is brought in this paper. The latter is a sampling-based algorithm based on the RRT* algorithm compared to the other optimization-based algorithm. A heuristic is introduced to convert the complex non-convex optimization planning task to a convex optimization problem. Next, MVP algorithm enhancement is proposed to reduce the calculation time. Both algorithms are tested on a selected testing scenario using a high fidelity nonlinear single-track model implemented in Matlab & Simulink environment.

Decoupling of vehicle lateral dynamics using four-wheel steering system

  • Autoři: Belák, J., doc. Ing. Tomáš Haniš, Ph.D.,
  • Publikace: Proceedings of the 23rd International Conference on Process Control. Piscataway: IEEE, 2021. p. 243-248. ISBN 978-1-6654-0330-6.
  • Rok: 2021
  • DOI: 10.1109/PC52310.2021.9447489
  • Odkaz: https://doi.org/10.1109/PC52310.2021.9447489
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    The era of highly automated and namely renaissance of electric vehicles brings new vehicle interior configuration and concept of operations. The fully independent steering for each wheel vehicle concepts are reality. This paper presents a lateral control algorithm providing both low and more important high velocity dynamical steering capabilities. The main contribution of the presented work is utter decoupling of vehicle lateral motion. The car side velocity and cornering maneuver could be commanded and executed independently, assuring higher stability during high speed/highway maneuvers and unmatched nimbleness at low speed/city operations. Furthermore, the wheel side slip angle based control system provides full and independent utilization of each wheel traction ellipse in a lateral sense. Therefore the active safety on wheel level in guaranteed as the tire to road limits are actively preserved for each wheel. The resulting steer-by-wire systems seamlessly augment human driver commands and provides autonomous vehicles with active stabilization functionality.

Lateral Driving Envelope Protection Using Cascade Control

  • Autoři: Ing. Denis Efremov, Zhyliaiev, Y., Kashel, B., doc. Ing. Tomáš Haniš, Ph.D.,
  • Publikace: Proceedings of 21st International Conference on Control, Automation and Systems. USA: IEEE Computer Society, 2021. p. 1440-1446. ISSN 2093-7121. ISBN 978-89-93215-21-2.
  • Rok: 2021
  • DOI: 10.23919/ICCAS52745.2021.9650058
  • Odkaz: https://doi.org/10.23919/ICCAS52745.2021.9650058
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    The steer-by-wire technology opens a possibility to create new advanced driver assistant systems. This work proposes a control structure that keeps the lateral vehicle dynamics in predefined stability boundaries and prevents the dominant sliding motion. We intentionally employed a cascade control law design suited for embedded platforms, often with low computational capacity. The proposed control hierarchical architecture is heavily inspired by aerospace domain solution, the flight envelope protection algorithms, which are still used in modern civil aircraft. The vehicle lateral acceleration is selected as the control system reference signal, commanded by a driver. The controller tracks such reference signal while respecting the driving envelope and vehicle operation safety limits. Several driving experiments were conducted to evaluate the proposed control structure in the statistical sense. The comparison with solution based on model predictive control framework and baseline vehicle without any assistance system is presented. Performed experiments were evaluated based on objective vehicle performance, like lap time and a number of collisions, combined with a human driver’s subjective evaluation. Experiments clearly show the incoherence of results and biased of skilled drivers. The objectively better vehicle performance, faster lap time with fewer collisions, received a lower subjective evaluation from experienced drivers used to current driving style.

Self-Supervised Learning of Camera-based Drivable Surface Friction

  • DOI: 10.1109/ITSC48978.2021.9564894
  • Odkaz: https://doi.org/10.1109/ITSC48978.2021.9564894
  • Pracoviště: Katedra kybernetiky, Katedra řídicí techniky, Skupina vizuálního rozpoznávání
  • Anotace:
    The visual predictor of a drivable surface friction ahead of the vehicle is presented. The image recognition neural network is trained in self-supervised fashion, as an alternative to tedious, error-prone, and subjective human annotation. The training images are labelled automatically by surface friction estimates from vehicle response during ordinary driving. The Unscented Kalman Filter algorithm is used to estimate tire-to-road interface friction parameters, taking into account the highly nonlinear nature of tire dynamics. Finally, the overall toolchain was validated using an experimental subscale platform and real-world driving scenarios. The resulting visual predictor was trained using about 3 000 images and validated on an unseen set of 800 test images, achieving 0.98 crosscorrelation between the visually predicted and the estimated value of surface friction.

Self-Supervised Learning of Camera-based Drivable Surface Roughness

  • DOI: 10.1109/IV48863.2021.9575288
  • Odkaz: https://doi.org/10.1109/IV48863.2021.9575288
  • Pracoviště: Katedra kybernetiky, Katedra řídicí techniky, Skupina vizuálního rozpoznávání
  • Anotace:
    A self-supervised method to train a visual predictor of drivable surface roughness in front of a vehicle is proposed. A convolutional neural network taking a single camera image is trained on a dataset labeled automatically by a cross-modal supervision. The dataset is collected by driving a vehicle on various surfaces, while synchronously recording images and accelerometer data. The surface images are labeled by the local roughness measured using the accelerometer signal aligned in time. Our experiments show that the proposed training scheme results in accurate visual predictor. The correlation coefficient between the visually predicted roughness and the true roughness (measured by the accelerometer) is 0.9 on our independent test set of about 1000 images. The proposed method clearly outperforms a baseline method which has the correlation of 0.3 only. The baseline is based on surface texture strength without any training. Moreover, we show a coarse map of local surface roughness, which is implemented by scanning an input image with the trained convolutional network. The proposed method provides automatic and objective road condition assessment, enabling a cheap and reliable alternative to manual data annotation, which is infeasible in a large scale.

Driving Envelope Definition and Envelope Protection Using Model Predictive Control

  • DOI: 10.23919/ACC45564.2020.9147211
  • Odkaz: https://doi.org/10.23919/ACC45564.2020.9147211
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Drive-by-wire technology opens a possibility to help the driver to drive a vehicle safely with support made by electronic control units. This paper presents an approach for defining a Driving Envelope that excludes any not welldefined vehicle states both for longitudinal and lateral dynamics. The second contribution is the design of a Model Predictive Controller for envelope protection that prevents critical situations such as the spinning of the vehicle, blocking of a wheel, and loss of the wheel traction. Validation results demonstrating the performance of the approach are obtained from a fixedsimulator with implemented high-fidelity twin-track model.

Haptic Driver Guidance for Lateral Driving Envelope Protection Using Model Predictive Control

  • Autoři: Ing. Denis Efremov, doc. Ing. Tomáš Haniš, Ph.D., Klaučo, M.
  • Publikace: Proceedings of 31st IEEE Intelligent Vehicles Symposium. Institute of Electrical and Electronics Engineers Inc, 2020. p. 1992-1997. ISSN 2642-7214. ISBN 978-1-7281-6673-5.
  • Rok: 2020
  • DOI: 10.1109/IV47402.2020.9304663
  • Odkaz: https://doi.org/10.1109/IV47402.2020.9304663
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    This paper presents an approach of utilizing Driving Envelope (DE) restrictions to assist the driver in lateral maneuvers. Two fundamental issues are addressed in this work. First, DE protection. Second, how to implement such functionality on a conventional car configuration, where the driver still needs to be a part of the control loop. The proposed functionality is based on a Model Predictive Controller (MPC). Vehicle states are constrained to avoid car critical spin situations (DE protection). The power-assisted steering system is used to guide the driver inside boundaries defined by the DE. The proposed architecture is compared with the standard car, without such an Advanced Driver-Assistance System (ADAS), by means of virtual ride tests performed using a high-fidelity vehicle model.

Model Predictive Control of a Vehicle using Koopman Operator

  • DOI: 10.1016/j.ifacol.2020.12.2469
  • Odkaz: https://doi.org/10.1016/j.ifacol.2020.12.2469
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    This paper continues in the work from Cibulka et al. (2019) where a nonlinear vehicle model was approximated in a purely data-driven manner by a linear predictor of higher order, namely the Koopman operator. The vehicle system typically features a lot of nonlinearities such as rigid-body dynamics, coordinate system transformations and most importantly the tire. These nonlinearities are approximated in a predefined subset of the state-space by the linear Koopman operator and used for a linear Model Predictive Control (MPC) design in the highdimension state space where the nonlinear system dynamics evolve linearly. The result is a nonlinear MPC designed by linear methodologies. It is demonstrated that the Koopman-based controller is able to recover from a very unusual state of the vehicle where all the aforementioned nonlinearities are dominant. The controller is compared with a controller based on a classic local linearization and shortcomings of this approach are discussed.

Safety-extended Explicit MPC for Autonomous Truck Platooning on Varying Road Conditions

  • DOI: 10.1016/j.ifacol.2020.12.1381
  • Odkaz: https://doi.org/10.1016/j.ifacol.2020.12.1381
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Automotive platooning can significantly improve traffic safety and efficiency, but many control challenges need to be solved to function properly under realistic driving conditions. This paper proposes a novel multi-rate explicit model-predictive controller (eMPC) for safe autonomous distributed vehicle platooning in varying road friction conditions. A safety-augmented distributed predictive control formulation ensures safe vehicle spacing versus emergency braking of preceding vehicles given current friction estimates. This complex control problem is carefully formulated into an efficiently parametrized optimization problem realized as eMPC. The resulting platoon shows excellent performance in a complex vehicle dynamics co-simulation validation with low communication and computation demands.

Visually Assisted Anti-lock Braking System

  • DOI: 10.1109/IV47402.2020.9304807
  • Odkaz: https://doi.org/10.1109/IV47402.2020.9304807
  • Pracoviště: Katedra řídicí techniky, Skupina vizuálního rozpoznávání
  • Anotace:
    The concept of a visually-assisted anti-lock braking system (ABS) is presented. The road conditions in front of the vehicle are assessed in real time based on camera data. The surface type classification (tarmac, gravel, ice, etc.) and related road friction properties are provided to the braking control algorithm in order to adjust the vehicle response accordingly. The system was implemented and tested in simulations as well as on an instrumented sub-scale vehicle. Simulations and experimental results quantitatively demonstrate the benefits of the proposed system in critical maneuvers, such as emergency braking and collision avoidance.

Data-driven identification of vehicle dynamics using Koopman operator

  • DOI: 10.1109/PC.2019.8815104
  • Odkaz: https://doi.org/10.1109/PC.2019.8815104
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    This paper presents the results of identification of vehicle dynamics using the Koopman operator. The basic idea is to transform the state space of a nonlinear system (a car in our case) to a higher-dimensional space, using so-called basis functions, where the system dynamics is linear. The selection of basis functions is crucial and there is no general approach on how to select them, this paper gives some discussion on this topic. Two distinct approaches for selecting the basis functions are presented. The first approach, based on Extended Dynamic Mode Decomposition, relies heavily on expert basis selection and is completely data-driven. The second approach utilizes the knowledge of the nonlinear dynamics, which is used to construct eigenfunctions of the Koopman operator which are known by definition to evolve linearly along the nonlinear system trajectory. The eigenfunctions are then used as basis functions for prediction. Each approach is presented with a numerical example and discussion on the feasibility of the approach for a nonlinear vehicle system.

Introduction of Driving Envelope and Full-Time-Full-Authority Control for Vehicle Stabilization Systems

  • DOI: 10.1109/PC.2019.8815305
  • Odkaz: https://doi.org/10.1109/PC.2019.8815305
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    This paper introduces the idea of the full-time-fullauthority control, known from the flight control field, for the automotive industry. Also, it provides a derivation of a nonlinear single-track vehicle model for an over-actuated car and introduces the vehicle states feasibility set, called here driving envelope, inspired by aircraft flight envelope, providing safe operation zone limits for a vehicle. As an addition, authors show proof based on vehicle dynamic physics, what practical pros can bring the usage of the steered rear axle together with the front axle.

Vehicle longitudinal dynamics control based on LQ

  • DOI: 10.1109/PC.2019.8815044
  • Odkaz: https://doi.org/10.1109/PC.2019.8815044
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Trend of autonomous vehicles and e-mobility is in favor of an advanced control system development and deployment. Vehicle dynamics level control systems providing safety limits and high performance response, especially during high dynamics maneuvers, are necessary. This work provides solution for vehicle longitudinal dynamics (vehicle acceleration) considering physical limits given by road, tire and vehicle dynamics respectively. The goal is to maximize vehicle longitudinal acceleration by controlling each wheel longitudinal slip ratio. Considered mathematical model is non-linear single track model incorporating non-linear Pacejka magic formula as a tire model. Design model for control system is derived as a linearized state-space model at constant acceleration operation point. Therefore, the common linearization approach, at system equilibrium, is not possible and the linearization along system trajectory is used. Such solution results in involvement of LPV techniques, as vehicle velocity is state variable. Finally, the LQ optimal control framework is employed to deliver control algorithms providing constant vehicle acceleration trajectory tracing. This is accomplished by longitudinal slip ratio control for each wheel.

Active Gust Load Alleviation System for Flexible Aircraft: Mixed Feedforward/Feedback Approach

  • DOI: 10.1016/j.ast.2014.12.020
  • Odkaz: https://doi.org/10.1016/j.ast.2014.12.020
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Lightweight flexible blended-wing-body (BWB) aircraft concept seems as a highly promising configuration for future high capacity airliners which suffers from reduced stiffness for disturbance loads such as gusts. A robust feedforward gust load alleviation system (GLAS) was developed to alleviate the gust loading. This paper focuses on designing a feedback controller which would improve the robust performance of the feedforward controller in reducing the peaks in wing root moments at very short gust lengths. The simulation results show that when the new feedback compensator is engaged with the feedforward controller, the performance of the GLAS system is improved significantly in terms of reduction in wing root moments for shorter as well as for longer gusts. This reduction in the wing root moment's peaks provides potential structural benefits and weight savings.

Feed-Forward Control Designs

  • DOI: 10.1007/978-3-319-10792-9_7
  • Odkaz: https://doi.org/10.1007/978-3-319-10792-9_7
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    The potential advantages of blended wing body (BWB) aircrafts in terms of fuel efficiency are opposed by technical challenges such as the alleviaton of gust loads. Due to low wing loading, gusts generally have a more severe impact on BWB aircraft than on conventional aircraft wing tube aircraft.

BWB Aircraft Control System of Fixed Structure

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Optimal and robust control laws for upcoming high-capacity passenger aircraft are proposed in the paper. The delivered controllers are obtained by modern non-convex non-smooth optimization approach and feature very good performance, low complexity, and respect prescribed structure of the control architecture. Simulation results for a BWB near-future airliner are presented and discussed.

Flexible aircraft lateral control law of low order

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Overview of European collaborative project is presented in this paper and some results on lateral control law design for Blended Wing Body (BWB) type aircraft are given. Rigid body motions as well as flexible dynamic of the aircraft are considered. Recently developed H∞ optimization tools for fixed order robust controller are used to device lateral control augmentation system (CAS) with extremely low complexity.

Optimal sensors placement and spillover suppression

  • DOI: 10.1016/j.ymssp.2011.12.007
  • Odkaz: https://doi.org/10.1016/j.ymssp.2011.12.007
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    A newapproachtooptimalplacementofsensors(OSP)inmechanicalstructuresis presented.Incontrasttoexistingmethods,thepresentedprocedureenablesadesigner to seekforatrade-offbetweenthepresenceofdesirablemodesincaptured measure- ments and theeliminationofinfluenceofthosemodeshapesthatarenotofinterestina givensituation.Anefficientnumericalalgorithmispresented,developedfroman existingroutinebasedontheFischerinformationmatrixanalysis.Weconsidertwo requirementsintheoptimalsensorplacementprocedure.OntopoftheclassicalEFI approach,thesensorsconfigurationshouldalsominimizespilloverofunwantedhigher modes.WeusetheinformationapproachtoOSP,basedontheeffectiveindependent method(EFI),andmodifytheunderlyingcriteriontomeetbothofour requirements-to maximizeusefulsignalsandminimizespilloverofunwantedmodesatthesametime. Performanceofourapproachisdemonstratedbymeansofexamples,andaflexible BlendedWingBody(BWB)aircraftcasestudyrelatedtoarunningEuropean-levelFP7 researchproject'ACFA2020-ActiveControlforFlexible

Fuel Management System for Cruise Performance Optimisation on a large Blended Wing Body Airliner

  • Autoři: doc. Ing. Tomáš Haniš, Ph.D., Wildschek, A., Stroscher, F.
  • Publikace: 4th European Conference for Aerospace Sciences. Paříž: Eucass, 2011,
  • Rok: 2011
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Blended Wing Body (BWB) aircraft configurations have been proposed for significant fuel efficiency improvement on commercial transport. In order to fly with the optimum lift to drag ratio throughout most of the mission an adaptation of the centre of gravity (CG) by fuel redistribution is proposed in this paper. The most aft location of the CG which still is controllable is mainly limited by actuator bandwidth whereas the front CG location is limited by control authority of the trailing edge control surfaces. This paper provides an optimization of the CG position with regards to minimization of fuel consumption. Layout of the fuel tank system is illustrated. Moreover, active stabilisation of faulty CG positions is discussed.

Information-based sensor placement optimization for BWB aircraft

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Information approach to optimal sensor placement is called to assign accelerometers as effective indicators of flexible vibrations in a next-generation large passenger blended-wing-body aircraft (BWB). This step presents a crucial prerequisite for the subsequent design of active dampers, either separately or as a part of integrated flight controls / active damping systems. Results of the classical Fisher information matrix algorithm (FIM) are presented first. Their interpretation in terms of spillover of higher modes leads to a modification of the FIM routine that explicitly cares for the spillover issues and gives rise to slightly different and more convenient suggestions for the BWB sensor positions.

L∞-Optimal Feed-forward Gust Load Alleviation Design for a large Blended Wing Body Airliner

  • Autoři: doc. Ing. Tomáš Haniš, Ph.D., Wildschek, A., Stroscher, F.
  • Publikace: 4th European Conference for Aerospace Sciences. Paříž: Eucass, 2011,
  • Rok: 2011
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    The potential advantages of Blended Wing Body (BWB) aircraft in terms of fuel efficiency are opposed by technical challenges such as the alleviation of gust loads. Due to the low wing loading gusts generally have a more severe impact on BWB aircraft than on conventional aircraft. This paper presents the design and optimisation of a Gust Load Alleviation System (GLAS) for a large BWB airliner. Numeric simulations are performed with an aeroelastic model of the aircraft including GLAS in order to compute time series of modal displacements for deriving equivalent static load cases which are used for resizing of the aircraft structure.

Lateral control for flexible BWB high-capacity passenger aircraft

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Two different approaches for design of lateral control augmentation system for large blended-wing-body aircraft (BWB) with flexible structure are presented and asses in this paper. The most challenging issue is handling of rigid-body dynamics and flexible modes coupling. First, a more classical approach is employed giving rise to separate flight dynamics controller (H2 optimal, with sufficient roll-off) and an active damper for most prominent lateral flexible modes on top of that (mixed-sensitivity Hinf design). This approach proves successful and has obvious advantages related to the design process complexity, or implementation and testing issues. On the other hand, there is always a risk of potentially significant performance loss compared to a fully integrated design. For this reason, fully integrated design is also presented in the form of a fixed-order MIMO Hinf optimal FCS controller, obtained by means of direct non-convex non-smooth optimization package HIFOO.

Lateral Flight Dynamic Controller for Flexible BWB Aircraft

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Two different approaches for design of lateral control augmentation system for large blended-wing-body aircraft (BWB) with flexible structure are presented and asses in this paper. The most challenging issue is handling of rigid-body dynamics and flexible modes coupling. First, a more classical approach is employed giving rise to separate flight dynamics controller (H2 optimal, with sufficient roll-off) and an active damper for most prominent lateral flexible modes on top of that (mixed-sensitivity H∞ design). This approach proves successful and has obvious advantages related to the design process complexity, or implementation and testing issues. On the other hand, there is always a risk of potentially significant performance loss compared to a fully integrated design. For this reason, fully integrated design is also presented in the form of a fixed-order MIMO H∞ optimal FCS controller, obtained by means of direct non-convex non-smooth optimization package HIFOO.

Low Order H∞Optimal Control for ACFA Blended Wing Body

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Advanced non-convex non-smooth optimization techniques for fixed-order H infinity robust control are proposed in this paper for design of flight control systems (FCS) with prescribed structure. Compared to classical techniques - tuning of and successive closures of particular single-input single-output (SISO) loops like dampers, attitude stabilizers etc. - all loops are designed simultaneously by means of quite intuitive weighting filters selection. In contrast to standard optimization techniques, though (H2, H∞ optimization), the resulting controller respects the prescribed structure in terms of engaged channels and orders (e.g. P, PI, PID controllers). In addition, robustness w.r.t. multi model uncertainty is also addressed which is of most importance for aerospace applications as well

HYBRID CONTROLLER FOR GUST LOAD ALLEVIATION AND RIDE COMFORT IMPROVEMENT USING DIRECT LIFT CONTROL FLAPS

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    In this paper two robust H(infinite) feedback control laws are designed, one for active wing bending damping, and one for active damping of the wing and hull bending modes. For the latter, not only symmetrically commanded ailerons are used, but also the elevator and direct lift control (DLC) flaps. The control objective of these feedback laws is the reduction of fatigue of the wing roots, as well as the improvement of ride comfort. Two different H(infinite) control design methods, DK iteration and HIFOO, are applied and compared. For the additional compensation of turbulence excited peak loads, the active wing bending damper is augmented by an adaptive feed-forward controller which uses the modified output of an alpha probe mounted at the front fuselage as reference signal. Numeric simulations with a state-space model of the symmetric dynamics of a large airliner are performed for validation of the controllers' performances.

Optimal Sensor placement in flexible structures: Energy vs. Information Based criteria

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    This paper is concerned with the optimal placement of sensors (OSP) on flexible dynamical structures. In order to get as much information as possible about the system state at any given time - also in terms of robustness with respect to numerical issues and modeling errors or sensor noise - the optimal placement of the sensors is an important system design task. Two different approaches for OSP are considered: The first one maximizes the output information using an iterative elimination algorithm, while the second one evaluates the signal output energy that can be received by the sensors. The contribution of this paper is to emphasize the basic mathematical consistency of these two approaches as well as their application on a simple theoretical example.

Optimal sensors placement and elimination of undesirable mode shapes

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    A new approach to optimal placement of sensors in mechanical structures is presented. In contrast to existing methods, the presented procedure enables a designer to seek for a trade-off between the presence of desirable modes in captured measurements, and the elimination of influence of those mode shapes that are not of interest in a given situation. An efficient numerical algorithm is presented, developed from an existing routine based on the Fischer information matrix analysis. Performance of our approach is demonstrated be means of two simple textbook examples.

Line-of-sight stailization of an airbone camera system

  • Autoři: Řezáč, M., Žoha, J., doc. Ing. Tomáš Haniš, Ph.D.,
  • Publikace: 2008 PEGASUS-AIAA Student Conference. Prague: Czech Technical University, 2008,
  • Rok: 2008
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Paper describes the inertially stabilized platform carrying two cameras. This device should be used for tracking of standing or moving targets.

Stabilized Platform for UAV

  • Autoři: doc. Ing. Tomáš Haniš, Ph.D.,
  • Publikace: Proceedings of the 8th International Scientific-Technical Conference Process Control 2008. Pardubice: Univerzita Pardubice, 2008, pp. 94. ISBN 978-80-7395-077-4.
  • Rok: 2008
  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Main goal of this work was to design algorithm for inertial unit sensors data processing. Inertial unit task is to provide information about aircraft state during flight regardless of atmosphere disturbances or sensors measurement mistakes. Basic Kalman filter based algorithm uses discreet LTI state space models of system dynamic. Mathematical model of aircraft and wind shaping filter are nonlinear and time continuous models. We use extended Kalman filter because of nonlinear model of system dynamic. Problem with time continuous model is solved by continuous time step with data step in discreet moments. Measurements for data step are from relative sensors three axes gyroscope and accelerometer and absolute sensors three axes magnetometer and GPS receiver.

Za stránku zodpovídá: Ing. Mgr. Radovan Suk