Cooperative Control of Multiple Quadrotors for Transporting a Common Payload

Adaptive fuzzy sliding mode control of magnetic levitation system based on Interval Type-2 Fuzzy Neural Network Identification with an Extended Kalman–Bucy filter

In this paper, we design a variable-gain first order sliding mode, in which the adaptive gain is state-independent and designed by two types of smooth, monotonically increasing and bounded functions. We modify the structure of the sliding mode even further by using an amplifying overall scaling factor. Both of the variable gain and the scaling factor can improve the control accuracy. Then we apply the newly designed sliding mode to the attitude synchronization of spacecraft. Simulation results show that, compared with the constant gain sliding mode, the proposed design ensures much higher control precision evaluated by the attitude synchronization error without more fuel consumption.

For two-vehicle cooperative transportation control, the typical methods are to keep the relative heading angle of the two vehicles constant and to realize cooperative transportation by using the characteristics of mecanum wheels. These methods do not apply to the requirements of the highway scene for the trafficability and robustness of two-vehicle transportation. To solve these problems, a cooperative control method based on a time-varying distance model was proposed. First, a multiaxis all-wheel-steering kinematic model was constructed based on the proportional steering principle. The reference rotation angles of each wheel were output by the model predictive control (MPC), which could realize trajectory tracking, with the current vehicle state and longitudinal speed prediction sequence as inputs. Second, the leader–follower strategy was adopted to build a dynamic reference distance of the path-between-vehicles model based on trajectory tracking deviation, vehicle states, and road information. On this basis, a two-vehicle cooperative prediction equation was established, and it output the longitudinal speed of the follower through the MPC. Finally, Simulink/TruckSim cosimulation was used to verify the effectiveness of the cooperative control method, which provides a new control idea for improving the efficiency of bulk transportation. The effectiveness and robustness of the collaborative control strategy were verified by Simulink/TruckSim cosimulation and a real vehicle experiment, which provides a new control idea for improving the efficiency of large cargo transportation.

A new cooperative braking control strategy (CBCS) is proposed for a parallel hybrid electric vehicle (HEV) with both a regenerative braking system and an antilock braking system (ABS) to achieve improved braking performance and energy regeneration. The braking system of the vehicle is based on a new method of HEV braking torque distribution that makes the antilock braking system work together with the regenerative braking system harmoniously. In the cooperative braking control strategy, a sliding mode controller (SMC) for ABS is designed to maintain the wheel slip within an optimal range by adjusting the hydraulic braking torque continuously; to reduce the chattering in SMC, a boundary-layer method with moderate tuning of a saturation function is also investigated; based on the wheel slip ratio, battery state of charge (SOC), and the motor speed, a fuzzy logic control strategy (FLC) is applied to adjust the regenerative braking torque dynamically. In order to evaluate the performance of the cooperative braking control strategy, the braking system model of a hybrid electric vehicle is built in MATLAB/SIMULINK. It is found from the simulation that the cooperative braking control strategy suggested in this paper provides satisfactory braking performance, passenger comfort, and high regenerative efficiency.

Second order sliding mode controllers for altitude control of a quadrotor UAS: Real-time implementation in outdoor environments

This chapter deals with the tracking problem of robot manipulators. These systems are described by highly nonlinear and coupled equations. Higher order sliding mode controllers are then proposed to ensure stability and robustness of uncertain robot manipulators. The motivation for using high order sliding mode mainly relies on its appreciable features, such as high precision and elimination of chattering in addition that ensures the same performance of conventional sliding mode like robustness. In this chapter we propose two high order sliding mode controllers. The first guarantees a continuous control eliminating the chattering phenomenon. Instead of a regular control input, the derivative of the control input is used in the proposed control law. The discontinuity in the controller is made to act on the time derivative of the control input. The actual control signal obtained by integrating the derivative control signal is smooth and chattering free. The second controller is an adaptive version of high order sliding mode controller. The goal is to obtain a robust high order sliding mode adaptive gain control law to respect to uncertainties and perturbations without the knowledge of uncertainties/perturbations bound. The proposed controller ensures robustness, precision and smoothness of the control signal. The stability and the robustness of the proposed controllers can be easily verified by using the classical Lyapunov criterion. The proposed controllers are tested to a three-degree-of-freedom robot to prove their effectiveness.

In this paper, a Novel Super-Twisting Algorithm combined with Improved Second - Order Sliding Mode (NSTASOSM) for the Field-Oriented Control (FOC) of high performance SPIM drives is proposed. This structure, on the one hand, effectively solves the weaknesses of traditional backstepping control (BS) and sliding mode (SM) control that are the dependent on the change of parameters, load disturbance and the phenomenon of chattering, on the other hand, increases the convergence speed and the reference tracking ability, enhance the robust and stably of drive systems even when working in conditions of uncertain parameter and load disturbances, eliminates the chattering phenomenon. The obtained results by simulation using the Matlab/ Simulink tool verified the performance of this proposed control structure.

This study aimed to develop a blended learning model in vocational education. This research used the stages of ADDIE model. The research was carried out at Universitas Negeri Padang, Indonesia. The instruments used were questionnaires, observation sheets, and cognitive, affective, and psychomotor tests. The results were (1) Blended learning models include: (a) the philosophical component of essentialism and pragmatism; (b) learning theory: behaviorism, cognitivism, and connectivism (c) the 4C component of communication, collaboration, cooperation, and creativity; (d) component of the industrial revolution 4.0: includes learning with digital elements with data literacy, technological literacy, and human literacy. (2) The blended learning model is centered on learning done offline and online makes it has a clear proportion of learning patterns. The flexibility of learning anytime and anywhere through face-to-face communication, as well as online interactions using online chats and forums to explore critical thinking through discussion. It also includes elements of students to be creative and innovative in projects and project improvement, as well as online teaching materials that are made interesting by the presence of multimedia components (text, images, and videos). (3) The result product is in the form of a model book, lecturer manuals and student guides, and textbooks, which are declared valid and practical so that the blended learning model can be applied in learning. (4) The achievements found are related to cognitive, affective, psychomotor and 4C abilities.

Recently, smart grid networks are researched and developed for the greening of the energy consumption. When introducing these into the university or the community, it is required not only the wide area cooperation and the high-speed monitoring & control, but also the construction of the heterogeneous infrastructure with the security and the flexibility. In this paper, recent research on the Radio on Fiber (RoF) technologies are described, and the technology application to the university and/or community smart grid is suggested. And also it is proposed the wide area remote connection of heterogeneous cognitive radio networks by RoF-MIMO (Multiple Input Multiple Output) technologies. Network throughput and the network outage rate using various types of RoF-MIMO systems are calculated and compared. And it is shown that the distributed parallel RoF-MIMO can improve the throughput and the outage performance simultaneously. Prototyping Experiment is also conducted in the faculty building and confirms that the network outage is improved by the distributed parallel RoF-MIMO.

The European Coexistence Bureau (ECoB) was created in 2008 by DG AGRI and the JRC to implement the Agriculture Council conclusions of 22 May 2006 in which the Council invited the Commission to engage in works related to coexistence in close cooperation with Member States and stakeholders. Among others the Council invited the Commission to identify the best practices for technical segregation measures and to develop crop-specific guidelines for coexistence regulations while leaving Member States necessary flexibility to adapt the recommendations to their specific climatic and agricultural conditions.\n\nECoB, located in the premises of JRC Institute of Prospective Technological Sciences, consists of Secretariat (formed by permanent JRC staff and seconded national experts) and crop-specific technical working groups consisting of technical experts nominated by interested Member States (currently only one, dealing with maize crop production). \nThe management practices for maize crop production proposed in this Best Practice Document (BPD) are a result of a consensus building process which started in October 2008. The ECoB Secretariat is responsible for collection of inputs from and exchange of information between them, analysis of the collected data and preparation of drafts of the Best Practice Document for consultation. ECoB Secretariat proposes compromise solutions on controversial issues, if necessary. This Best Practice Document was adopted by consensus within the EcoB in May 2010.

This article proposes the document model of a hybrid knowledge-based document analysis system for business letters. The model combines requirements of object-oriented representation of both, documents as well as knowledge necessary for analysis tasks, and is based on the ODA platform. Model-driven document analysis increases the flexibility of a system because several analysis specialists can be used in co-operation to assist each other and to improve the results of analysis. The inherent modularity of the system allows for a reuse of knowledge sources and integral constituents of the architecture in other document classes such as forms or cheques.

In this article, a robust nonlinear tracking control design for ionic polymer metal composite (IPMC) with uncertainties is presented by using particle swarm optimization (PSO) based sliding mode approach. In detail, for a nonlinear dynamic model with uncertainties, an IPMC artificial muscles position tracking control system based on sliding mode control approach is presented, where, a saturation function is used in the sliding mode control law design to suppress chattering, and the control parameters of sliding mode control are optimized by using particle swarm optimization to obtain quick convergence. The robust stability can be guaranteed. Finally, the effectiveness of the proposed method is confirmed by simulation results.

A traction force controller for passenger cars is presented in this paper to solve, in particular, the problem of guaranteeing the satisfaction of the fastest stable acceleration/deceleration conditions during vehicle operations. This problem is, for instance, an important subtask in the design of Intelligent vehicles/highways systems (IVHS), but it can be considered crucial also for any kind of modern medium to high-performance commercial cars. Due to system uncertainties, time-varying road conditions, and the wide range of operating conditions, which are typical of the automotive context, a robust control technique is required to solve this problem. The robust control methodology adopted in this paper is the so-called second order sliding mode control, which results particularly suitable to deal with uncertain nonlinear time-varying systems. Moreover, in contrast to conventional sliding mode control, second order sliding mode control generates continuous control actions, the discontinuities being confined to the derivatives of the control signals, thus resulting particularly suitable to be applied to automotive systems where vibrations suppression is a crucial requirement.

This paper presents a novel fuzzy logic based Adaptive Super-twisting Sliding Mode Controller for the control of dynamic uncertain systems. The proposed controller combines the advantages of Second order Sliding Mode Control, Fuzzy Logic Control and Adaptive Control. The reaching conditions, stability and robustness of the system with the proposed controller are guaranteed. In addition, the proposed controller is well suited for simple design and implementation. The effectiveness of the proposed controller over the first order Sliding Mode Fuzzy Logic controller is illustrated by Matlab based simulations performed on a DC-DC Buck converter. Based on this comparison, the proposed controller is shown to obtain the desired transient response without causing chattering and error under steady-state conditions. The proposed controller is able to give robust performance in terms of rejection to input voltage variations and load variations.

Department of Defense Regulation requires designers to evaluate the robustness of their designs using phase and gain margin criteria. Given that such criteria are applicable to linear designs, their inapplicability in their current definition to Higher Order Sliding Mode (HOSM) control designs; non-linear designs techniques in the time domain appeared to constitute a major hindrance to the application of HOSM techniques to aircraft and missiles. This paper illustrates the usage of new phase and gain margin techniques applicable to HOSM designs for providing measures of robustness such designs. The technique consists in replacing the -1 singularity point used with linear designs with describing function based representations of the HOSM controller. It is applied here to general problem of guidance of aerospace vehicles steered with aerodynamic lift that is, to a control problem with relative degree = 3. In the application case we assume the unavailability of attitude measurements. Results show that whether the guidance enforces the collision condition or a proportional integral linear manifold has little effect on the robustness. The concept of practical Relative Degree is introduced and applied instead of the strict definition thereof.