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The motivation to perform research on feedback control system for unmanned aerial vehicles, a fact that each quadrocopter is unstable.

For this reason, it is necessary to design a control system which is capable of making unmanned aerial vehicle vertical take-off and landing (UAV VTOL) stable and controllable. For this purpose, it was decided to use a feedback control system with cascaded PID controller. The main reason for using it was that PID controllers are simple to implement and do not use much hardware resources. Moreover, cascaded control systems allow to control object response using more parameters than in a standard PID control. STM32 microcontrollers were used to make a real control system. The rapid prototyping using Embedded Coder Toolbox, FreeRTOS and STM32 CubeMX was conducted to design the algorithm of the feedback control system with cascaded PID controller for unmanned aerial vehicle vertical take-off and landings (UAV VTOLs).

During research, an algorithm of UAV VTOL control using the feedback control system with cascaded PID controller was designed. Tests were performed for the designed algorithm in the model simulation in Matlab/Simulink and in the real conditions.

It has been proved that an additional control loop must have a full PID controller. Moreover, a new library is presented for STM32 microcontrollers made using the Embedded Coder Toolbox just for the research. This library enabled to use rapid prototyping while developing the control algorithms.

The purpose of this paper is to apply the proportional integral (PI) control algorithm in discrete manufacturing enterprises to maintain lower and steadier work in progress so as to improve on‐time delivery.

A sensitivity constrained optimization model is designed on the frequency domain, whose optimum algebraic solutions are then obtained easily. Two controllers, a backlog controller and an input‐rate controller, are devised, which correspond to the integral control and the proportional control of PI controllers, respectively. Interacting with each other, these controllers have made the engineering implementation of PI controllers a reality.

Simulation is carried out in certain motorcycle production lines. Results confirm that PI controllers also possess good control effects in the discrete manufacturing industry, as well as in the process industry.

A continued departure from the nominal may happen repeatedly if the root causes of changing are not detected and identified. Moreover, PI controllers can mask process defects, failures, and drifts, and this may lead to eventual catastrophic failures. So, statistical process control should be utilized in PI controlled processes to detect significant changes for long‐term process improvement.

PI controllers possess potential in discrete enterprises.

PI controllers are tried for process improvement in discrete manufacturing enterprises.

Increases in air traffic and air traffic controller workload lead to a need to provide assistance to the air traffic controller. Proposes and validates a new organization of air traffic control, which allows air traffic controllers to remain active in the control and supervisory loop of the process, in order to maintain the present traffic safety level and to improve the global system performances. Consists of decomposing the problem according to the two levels of the air traffic control organization. Directs the first step towards a horizontal cooperation that consists of a dynamic allocation of the tactical level control tasks between human air traffic controllers and an assistance tool. Presents the dynamic task allocation principles, and describes the experimental platform for task allocation in air traffic control. Describes the experimental protocol used for the experiments with qualified controllers and presents the first results. They show the real help a dynamic task allocation provides to the air traffic controllers.

During flight, a small-size autonomous helicopter will suffer external disturbance that is wind gust. Moreover, the small-size helicopter can carries limited payload or battery. Therefore control system of an autonomous helicopter should be able to eliminate external disturbance and optimize energy consumption. The purpose of this paper is to propose a hybrid controller structure to control a small-size autonomous helicopter capable to eliminate external disturbance and optimize energy consumption. The proposed control strategy comprise of two components, a linear component to stabilize the nominal linear system and a discontinuous component to guarantee the robustness. An integral control is included in the system to eliminate steady state error and tracking reference input.

This research started with derived mathematic model of the small-size helicopter that will be controlled. Based on the obtained mathematic model, then design of a hybrid controller to control the autonomous helicopter. The hybrid controller was designed based on optimal controller and sliding mode controller. The optimal controller as main controller is used to stabilize the nominal linear system and a discontinuous component based on sliding mode controller to guarantee the robustness.

Performance of the proposed controller was tested in simulation. The hybrid controller performance was compared with optimal controller performance. The hybrid controller has better performance compared with optimal controller. Results of the simulation shows that the proposed controller has good performance and robust against external disturbances. The proposed controller has better performance in rise time, settling time and overshoot compared with optimal controller response both for step input response and tracking capability.

Hybrid controller to control small-size helicopter has not reported yet. In this research new hybrid controller structure for a small size autonomous helicopter was proposed.

In recent years it has been illustrated that the Unified Power Flow Controller (UPFC) installation location plays an important role in effecting nonlinearly its steady state performance. A Pulse Width Modulation (PWM) based UPFC used as a voltage regulator is modeled and analyzed to investigate its optimal position in the transmission line. From the simulation results it is demonstration that by varying the modulation index of the device it can control the distribution of the active and reactive power flows. In addition, this paper deals with the definition and simulation of the control strategy of the closed‐loop UPFC with a series compensation block when it operates as a terminal voltage regulator using Electromagnetic Transients Program (EMTP). The design and simulation of two types of digital controller strategies for the study system in this paper have been carried out. The dynamic performance in terms of speed stability, accuracy, robustness and simplicity of a PI controller with gain scheduling and a fuzzy logic controller have been tested and compared.

The purpose of the paper is to find a simple structure of speed controller robust against drive parameter variations. Application of neuro‐fuzzy technique in the controller of PI type creates proper nonlinear characteristics, which ensures controller robustness.

The robustness of the controller is based on its nonlinear characteristic introduced by neuro‐fuzzy technique. The paper proposes a novel approach to neural controller synthesis to be performed in two stages. The first stage consists in training the neuro‐fuzzy system to form the proper shape of the control surface, which represents the nonlinear characteristic of the controller. At the second stage, the PI controller settings are adjusted by means of the random weight change procedure, which optimises the control quality index formulated in the paper. The synthesis is performed using simulation techniques and subsequently the behavior of a laboratory speed control system is validated in the experimental setup. The control algorithms of the system are performed by a microprocessor floating point DSP control system.

The proposed controller structure with proper control surface created by the neuro‐fuzzy technique guarantees expected robustness.

The proposed controller was tested on a single machine under well defined conditions. Further investigations are required before any industrial applications can be made.

The proposed controller synthesis and its results may be very helpful in the robotic system where changing of system parameters is characteristic for many industrial robots and manipulators.

The original method of robust controller synthesis was proposed and validated by simulation and experimental investigations.

The present paper aims to focus on the role which German controllers play so far in the process of sustainable transformation in for-profit organizations, the current obstacles to a wider engagement here and ways to overcome these obstacles.

The analysis combines two qualitative study designs. Empirical data is generated via a job advertisement analysis and an explorative survey with 107 subjects from management accounting/controlling and sustainability management. The generated data is interpreted against the background of the theory of institutional logics and Abbott’s (1988) theory of professional jurisdiction.

We find that controllers are in a state of tension. On the one hand, the pressure to integrate sustainability into companies is increasing. On the other hand, they seem to be rather reluctant to get involved. The institutional logics that shape their profession play an important role here, as does an unclear relationship with the sustainability department, which has its own claims here. Based on these observations, we identify the core obstacles to the transformation of the controllers’ profession and discuss solutions which can guide the transformation of this profession.

The present paper provides insights from a unique combination of different quantitative study designs and different perspectives on the possible role that controllers can play in advancing sustainable transformation in companies.

A switching depth controller based on a variable buoyancy system (VBS) is proposed to improve the performance of small autonomous underwater vehicles (AUVs). First, the requirements of VBS for small AUVs are analyzed. Second, a modular VBS with high extensibility and easy integration is proposed based on the concepts of generality and interchangeability. Subsequently, a depth-switching controller is proposed based on the modular VBS, which combines the best features of the linear active disturbance rejection controller and the nonlinear active disturbance rejection controller.

The controller design and endurance of tiny AUVs are challenging because of their low environmental adaptation, limited energy resources and nonlinear dynamics. Traditional and single linear controllers cannot solve these problems efficiently. Although the VBS can improve the endurance of AUVs, the current VBS is not extensible for small AUVs in terms of the differences in individuals and operating environments.

The switching controller’s performance was examined using simulation with water flow and external disturbances, and the controller’s performance was compared in pool experiments. The results show that switching controllers have greater effectiveness, disturbance rejection capability and robustness even in the face of various disturbances.

A high degree of standardization and integration of VBS significantly enhances the performance of small AUVs. This will help expand the market for small AUV applications.

This solution improves the extensibility of the VBS, making it easier to integrate into different models of small AUVs. The device enhances the endurance and maneuverability of the small AUVs by adjusting buoyancy and center of gravity for low-power hovering and pitch angle control.

This paper aims to propose a new linear parameter varying (LPV) controller for the robot tracking control problem. Using the identification of the robot dynamics in different work space points about modeling trajectory based on the least square of error algorithm, an LPV model for the robotic arm is extracted.

Parameter set mapping based on parameter component analysis results in a reduced polytopic LPV model that reduces the complexity of the implementation. An approximation of the required torque is computed based on the reduced LPV models. The state-feedback gain of each zone is computed by solving some linear matrix inequalities (LMIs) to sufficiently decrease the time derivative of a Lyapunov function. A novel smoothing method is used for the proposed controller to switch properly in the borders of the zones.

The polytopic set of the resulting gains creates the smooth switching polytopic LPV (SS-LPV) controller which is applied to the trajectory tracking problem of the six-degree-of-freedom PUMA 560 robotic arm. A sufficient condition ensures that the proposed controller stabilizes the polytopic LPV system against the torque estimation error.

Smoothing of the switching LPV controller is performed by defining some tolerances and creating some quasi-zones in the borders of the main zones leading to the compressed main zones. The proposed torque estimation is not a model-based technique; so the model variation and other disturbances cannot destroy the performance of the suggested controller. The proposed control scheme does not have any considerable computational load, because the control gains are obtained offline by solving some LMIs, and the torque computation is done online by a simple polytopic-based equation.

In this paper, a new SS-LPV controller is addressed for the trajectory tracking problem of robotic arms. Robot workspace is zoned into some main zones in such a way that the number of models in each zone is almost equal. Data obtained from the modeling trajectory is used to design the state-feedback control gain.

We develop and validate measurement instruments for the business partner, watchdog, and scorekeeper roles of controllers. This study addresses calls to enhance the quality of survey research in management accounting by devoting more attention to scale development and especially to construct validity. By focusing on the activity sets of the controllers’ roles, we provide a theoretically and empirically grounded picture of their current roles. The measurement instruments presented in this study enable systematic research progress on controller roles, their relationships, antecedents, and performance outcomes.