In this study, we adopt a dual power system for extension (DPES) operation by combining the existing power system of an electric vehicle with a hydrogen fuel cell. This was to enhance the durability of the electric vehicle and reduce the inconvenience of battery charging. The lithium battery acts as the primary power source and has real-time monitoring of its state of charge (SOC), while the hydrogen fuel cells act as the auxiliary power supply. The auxiliary power can be used either directly or for charging the lithium battery while the vehicle is in its idle state. The dual power system is coupled with a dual-mode motor controller and energy management system. This study aims to apply the dual power system on the electric vehicle using hydrogen fuel cells. We designed a simulation platform for real driving conditions using Labview to send and receive control commands. In this study, we simulated the road cycles of the Economic Commission for Europe (ECE-40), Japanese legislative cycle (JP10) and the World-wide Motorcycle Emissions Test Cycle (WMTC), using Proportional-integral Control (PI) for automatic tracking and employing engineering error analysis to determine the most suitable PI parameter values for the simulated system. The results showed that using a fixed 100 W fuel cell could enhance the operation time up to 21 %, 21 %, and 14 % for the road cycles of the ECE-40, JP10, and WMTC, respectively. Due to the required features of an actual vehicle, we also designed an energy limiting system to manage the driver-controlled electronic throttle by controlling the instantaneous and maximum power output of the motor in order to achieve savings in energy consumption, increase its operation time, protect the system, and enhance its durability.

This paper describes the development of a wearable interface that exploits the user’s natural arm movements to intuitively control a robotic manipulator. The design is intended to alleviate the time and effort spent in operating the robotic manipulator, regardless of the age and technological experience of the user. The interface is made to be low-cost, comfortably worn, and easy to put on and remove. Kinematic models of human and robot arms are used to produce a natural mapping from the user’s arm movements to the commanded movements of the robotic manipulator. An experiment is conducted with 30 participants of varied ages and experience to assess the usability of the wearable interface. Each of the participants is assigned to perform a pick and place task using two of three different interfaces (the wearable interface, a game controller, and a mobile interface running on a tablet computer) for a total of 60 trials. The results of the study show that the wearable interface is easier to learn compared to the alternative interfaces and is chosen as the preferred interface by the participants. Performance data shows that the users complete the pick and place task faster with the wearable interface than with the alternative interfaces.

This paper discusses the application of second order mode controls to hydraulic valve-cylinder drives with a special focus on the limitations resulting from nonlinear dynamic effects in flow control valves. Second order sliding mode algorithms appear highly attractive in the successive implementation of sliding mode control, achieving continuous control inputs, while maintaining the main properties of sliding modes. Under certain model assumptions, some of these controllers may even be applied as output feedback controllers. However, intrinsic nonlinear dynamic effects of hydraulic valves such as slew rates and time delays arising in the amplification stages, limits the applicability of such methods, and may lead to partial losses of robustness and limit cycles. These properties are analyzed and experimentally verified, and compensation methods are proposed. The application of the second order sliding algorithm known as the super twisting controller is considered for output feedback control and compared with conventional first order sliding mode control. The controllers under consideration are applied for position tracking control of a hydraulic valve-cylinder drive exhibiting strong variations in inertia- and gravitational loads. Results demonstrate that the super twisting algorithm may be successfully applied for output feedback control of hydraulic valve-cylinder drives, with modifications guaranteeing robust control performance in a small vicinity of the control target.

The paper presents the motion simulation of a Wing in Ground craft with a Lippisch configuration which is stable in terms of static stability. The influence of wind and wave perturbations on the dynamic stability of the flight are investigated. The analysis of safety and stability used two different approaches. Based on frequency domain simulation, the first approach derived from the classical stability theory utilizes the aerodynamic coefficients and their linearized derivatives. The second approach based on time domain simulation uses the coefficients with full respect to the nonlinear character of aerodynamics in ground effect. The trajectory is used to evaluate the dynamic stability and flight safety of the craft. From the results for typical perturbations, the limitations of the classical stability theory for the flight safety of Wing in Ground craft are shown. The results show the necessity of the automatic control system even for a satisfying stable craft predicted by the linear theory. The demand of high performance together with the hard constraints for states and control inputs are challenging for the controller design. A proportional-integral-derivative controller is studied to secure the flight safety of small craft under different perturbation and a methodology for designing a control system for operation under various weather conditions is illustrated.

Micromachining processes deal with the production of parts characterized by features in the micro range (i.e., with dimension lower than 1 mm). Several works are present in literature analyzing the tool behaviors, the material influence on the process, and the machine design. In fact, the downsize of the process up to the microscale needs a full review of all the knowledge coming from the meso and macro scale. As a consequence, machines suitable for micromachining processes were recently introduced in the market. Usually, these machines are classified by the classical gantry layout structure supported by a granite frame and, in order to guarantee the needed requirements of precision and accuracy in the micro scale, they are based on fluid-supported axes and active and/or passive vibration control systems. This paper proposes a new concept design: a high precision machine (HPM) based on an innovative layout exploiting a differential mechanism with three motors for two degrees of freedom using pulleys and metal belts. This new layout exhibits relevant advantages. The most significant is that all the worktable servo drives, that moves along x and y axes, are ground-fixed. This allows to isolate the working area of the machine from the servo drives. The system of pulleys and belts holding the working table slides on air bearings in order to minimize the micro vibrations induced by all the drives. A further peculiarity of the machine consists of the double z-axis each of them is motorized by a micrometer slide with linear absolute encoder. The first z-axis is equipped with a spindle for performing micro machining processes (drilling and milling). The second z-axis is equipped with a laser head for micro ablation. The servo drives of the two z-axes are controlled by the same control system of the worktable. Another important feature of the proposed layout is that the differential configuration of the xy mechanism admits the use of a constant speed signal to each control reference with no output displacements. This allows to guarantee non-inversion of motion of the servo-drives and so the avoidance of problems due to backlash and/or static friction. Drives are controlled by position and speed control loops with PID architecture, anti-windup and feed forward strategies. Controllers have been tuned by the use of a genetic algorithm applied to a dynamic model of the system. As a general consideration, the quality of the investigated micro machining processes can be improved with the designed machine structure.

This study proposes a design of transmission mechanism which is referred to as a series-type independently controllable transmission (ICT). The series-type ICT is an alternative form of the parallel-types proposed in the former researches. The series-type ICT can serve as a continuously or an infinitely variable transmission mechanism, and it can also produce a required angular output velocity that can be independently manipulated by a controller and not affected by the angular velocity of the input shaft. The series-type ICT mechanism is composed of two planetary gear trains and two transmission-connecting members. Kinematic and dynamic characteristics of the ICT mechanism are analyzed and their analytical equations are derived for application in this study.

In recent years, energy consumption issues, boosted by environmental concerns, are becoming of paramount importance in the manufacturing field. In particular, machinery sector has been the theatre of several initiatives and projects aimed at an eco-efficient design and use of the machines. In this context, energy consumption modeling is considered a powerfull tool to foresee and optimize energy efficiency by design. On the other side, while each company has to develop numerical models of the internally designed machine elements, it has to be taken into account that machine productivity, eco-performance and cost are all strongly influenced by the employed commercial components (e.g. motors, sensors, controllers, transmissions, guide ways), that must be also be modeled but it is unrealistic to expect that the machinery builder develops by himself all required models. In this paper, the industrial adoption of simulation tools and methodologies for energy consumption modeling is regarded as an application of the more general “Model Based Product Development” methodology. In particular, the development of “functional component models”, seen as Virtual Components (“VC”) to be assembled in the Virtual Machine, is suggested as the key to foster co-modeling activity involving suppliers. A proper business model is then proposed to guarantee the sustainability of the co-operation scenario. Finally, the strategy concept is illustrated by some examples concerned with machine tool accessories and components.

Imitation learning is one of the forms of social learning that enables the human or robot agents to learn new skills. The knowledge acquired for imitation can be basically represented as action mapping based on “organ matching” which determines the correspondence between imitator and imitatee, if the imitator and the demonstrator share the same embodiment. In this paper, we aim at imitation of two system with totally different dynamics, imitating each other, where any correspondence is missing. Towards this aim, we adopt a case where the imitator is a fluidic system which dynamics is totally different than the imitatee, that is a human performing different body poses. Our work proposes the fluidics formation control of fluid particles where the formation results from the imitation of observed human body poses. Fluidic formation control layer is responsible of assigning the correct fluid parameters to the swarm formation layer according to the body poses adopted by the human performer. The movement of the fluid particles is modeled using the Smoothed Particle Hydrodynamics (SPH) which is a particle based Lagrangian method for simulation of fluid flows. The region based controller first extract the human body parts generating the regions where the attention is attracted by the imitatee and fits an appropriate ellipses to delimite boundaries of those regions. The ellipse parameters such as center of the ellipses, eccentricity, length of the major and minor axis etc. are used by the fludic layer in order to generate human body poses. This paper introduces our technique and demonstrates the imitation performance of our system.

Friction stir welding (FSW) is so quite promising that leads it to one of the preferred joining process for a wide range of applications especially for Aluminum. FSW machines are very expensive. The objective is to develop a simple and low cost technique to measure and control the force during FSW in a milling machine. Measurement of forces during welding is a difficult task. Many dynamic measuring devices such as dynamometers are available but each have their own advantages and disadvantages. A new approach to measure force while performing weld is discussed. First, incorporation of FSW in PKM 5-axes milling machine is done. The head of the machine is modified to support higher force levels that are generated during FSW. With the help of the NC-Controller, the force values are retrieved from the axes of the machine while performing weld through actuators. Forces were also measured from load cell and compared to estimate the quality of measurement.

This paper reports on a study whose objective is to explore the potential of intelligent algorithms such as fuzzy rules and neural networks (NN) as applied to the control of pneumatic servosystems. Current application is position control of a pneumatic gantry robot. Preliminary experiments with adaptive fuzzy and NN controllers showed improvement in tracking performance by upwards of 70%. This level of improvement was expected given the adaptive nature of both controllers. However, both methods also required significant effort to setup. An on-line autotuner was developed to improve the ease of implementation. Comparative results are given for five controllers: 1) manually tuned PID, 2) autotuned PID, 3) adaptive NN PID, 4) fuzzy adaptive PID and 5) autotuned fuzzy adaptive PID. Experiments were conducted at 2 different supply pressures and 3 different tracking frequencies. Once again the fuzzy adaptive PID controller improved performance over fixed gain PID, this time by upwards of 80%, even when both were given the benefit of autotuning.

Flexible-link robots are an important class of manipulators which uses lightweight arms for assembly, civil infrastructure, bridge/vehicle systems and large-scale space structures. The wide spread of these systems in various application areas has ensured that the modeling of flexible elements and the control of vibration have received a great deal of attention in recent years. In this work it is analyzed a two DOF parallel robot with two flexible links used for pick and place operations, developing a control strategy based on piezoelectric actuators and strain gauges or accelerometers embedded in the links. The analysis of the robot behaviour and the development of the controller, have been carried out on an electromechanical model built in Matlab ® and co-simulated with the multibody flexible model built in Adams ® . Results show positive confirmation of the study and encourage future tests on the real manipulator to validate the multibody model and the control strategy.

In industrial plants some parameters can not be evaluated properly or they are varying with time. These parametric uncertainties has to be taken into account during the design process of industrial systems. In this work, the developped optimization approach is applied on an industrial roll-to-roll sytem. Such systems are commonly used to handle materials as polymer, metal, paper and textile. The key challenge is to move the web at the expected speed while maintaining the web tension in an acceptable range around its reference. Moreover, the Young’s modulus of the web is difficult to evaluate and it is varying with time due to temperature and moisture variations. This paper deals with the web tension controller synthesis on a large-scale roll-to-roll system with uncertain Young’s modulus. To synthesize web tension controllers, an H∞ approach is applied and adapted to the system with parametric uncertainties using multi-objective robust design optimization.

Using hybrid powertrains is an attractive idea to reduce the fuel consumption in vehicles. Control strategy is the most challenging subject in designing of a hybrid powertrain. In this paper, an optimized control strategy based on the driving cycle type designed for a hydraulic hybrid bus has been presented. Because of considering the type of the driving cycle, the proposed control strategy can be named as an intelligent one. In this controller, at first, four standard driving cycles have been defined as the reference clusters. Then the optimized control strategy for each cluster has been derived using a dynamic programming algorithm. In addition, several multi-layered perceptron networks are modeled in order to use the output of each optimized control strategy. After that a clustering method with a feature selection algorithm has been implemented to assign degree of similarity to each cluster for the unknown driving cycle. Finally, a linear combination of four optimized control strategy outputs has been used for generating final output of the intelligent control strategy. In this combination, each output is weighted by the corresponding degree of similarity. Here, the hydraulic hybrid bus model is a feed forward one and has been simulated using a compound driving cycle. The compound driving cycle consists of six distinct 100s long portions of the Nuremburg driving cycle. The simulation results show that by using the intelligent control strategy, the fuel consumption of the hybrid bus has been reduced by almost 12% in comparison with the results of a rule-based control strategy.

In this paper, the synthesis and optimization problems of the transient performances, such as overshoot and setting time, of the output response with respect to a step signal for an under-damped second-order linear system are studied. The traditional control strategy and the switching control strategy are used, respectively. Our control objective is twofold: Objective 1 is to ensure that the overshoot of the system output does not violate the given safety bound and objective 2 is to ensure that the settling time is smaller than the given allowable time. The obtained results indicate that the switching control strategy has main two evident advantages: firstly, the switching proportional controllers can take advantages of both the quick response and the small overshoot of the output response. Secondly, the switching controller is always available, while the single proportional controller is available in some special cases. Finally, an example of servomotor is given to demonstrate the effectiveness of the proposed method.

For the simplified linear hypersonic air-breathing propulsion model, aiming at the safety boundaries existing during the working progressing, this paper considers the output regulation/ safety protection switching control problem. Several comments are given to the minimum control switching strategy studied in our previous work, and to make the designing of the switching controller more systematic, a novel command switching strategy is proposed, where discontinuous controllers are adapted. The protected output will be forced to escape from the safety boundary once the danger comes. The asymptotic tracking problem is transformed into the asymptotic stability problem of the linear switched and impulsive systems or that of the switched systems whose subsystems have different equilibrium points. The design of the dynamical output feedback controllers and the switching laws can be finished separately, and the principles guaranteeing asymptotic tracking are given, the decline of the candidate Lyapunov function can be checked by solving an optimal problem. Finally, simulations verify the effectiveness of the given results, which also indicate that the commands switching control can improve both the safety margin of the protected output and the tracking performance of the regulated output, the ability of tracking commands safely and quickly is thus enhanced.

This paper considers the problem of modeling and control of non-conservative flexible systems, whose dynamics is described by the wave equation. Classical modal analysis failed so far when the boundaries included dampers. A new insight into the problem was obtained by infinite dimension transfer functions models, developed in previous works. Their special structure, consisting of delays and low order rational terms lead to the time domain interpretation of traveling waves. In this paper the Laplace modeling approach is used to represent the solution in a modal like fashion, i.e. an infinite sum of products of spatial and temporal functions. While this form is closely related to standing waves, it was shown to lead also to a traveling wave representation. The response is then used to investigate the behavior of the system under control with the absolute vibration suppression (AVS) controller, which was originally designed for tracking control. It is shown that the vibration suppression properties of this controller apply also to nonzero initial conditions.

In this paper, we address the tracking control problem for switched nonlinear systems in strict-feedback form with time-varying output constraints. To prevent the output from violating the time-varying constraints, we employ a Barrier Lyapunov Function, which relies explicitly on time. Based on the simultaneous domination assumption, we design a controller for the switched system, which guarantees that asymptotic tracking is achieved without transgression of the constraints and all closed-loop signals remain bounded under arbitrary switchings. The effectiveness of the proposed results is illustrated using a numerical example.

This paper presents a novel autopilot for a 3D helicopter. From desired trajectories defined by the user for elevation and travel angles, the autopilot is computing the desired trajectory of the pitch angle. Furthermore, the autopilot allows to decouple the system and to define “virtual” inputs in order to separately design controllers for each attitude angle. Travel and elevation controllers are based on adaptive version of super-twisting algorithm: this class of controllers keeps the robustness feature of sliding mode while reducing the well-known drawback of such control approach, the chattering, thanks to the online adaptation of the controller gain.

The global stabilization of the classical ball & beam has been approached in the literature through saturated control which imposes restrictions on the reactivity of the closed loop. In this work a modified design for the classical ball & beam system is presented. The beam is driven by two actuators (see figure 1). In comparison to the classical system, this design offers an additional degree of freedom which is the vertical motion of the beam. We show that the new design offers the possibility to get rid of the closed loop low reactivity restriction. We propose two nonlinear controllers to steer the trajectories of the system towards a final desired position. The first controller adapts, to the new design, existing controllers from the literature for the classical ball & beam. The second controller uses the additional degree of freedom to provide a faster stabilization.

This paper adapts an Ant Colony intelligent Optimization algorithm (ACO) to four design problems important in Mechatronics applications: (1) Stress- and volume minimization of a helical compression spring subject to a set of geometrical and stress constraints for material volume minimization, (2) tuning the gains of a PID-controller for a second-order plant with a transport lag, (3) design of a planetary gear leg of a walking machine for a desired straight line trajectory and driving actuator torque, and (4) synthesis of four-bar mechanisms. A brief overview of the ACO algorithm is first presented and its adaptation to each design problem is explained and demonstrated by way of examples that have been solved by other optimization techniques for comparison. In all four examples, the ACO algorithm produced better results in terms of cost-function values while satisfying all necessary constraints.