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This paper aims to tele-operate the movement of an unmanned aerial vehicle (UAV) in the obstructed environment with asymmetric time-varying delays. A simple passive proportional velocity errors plus damping injection (P-like) controller is proposed to deal with the asymmetric time-varying delays in the aerial teleoperation system.

This paper presents both theoretical and real-time experimental results of the bilateral teleoperation system of a UAV for collision avoidance over the wireless network. First, a position-velocity workspace mapping is used to solve the master-slave kinematic/dynamic dissimilarity. Second, a P-like controller is proposed to ensure the stability of the time-delayed bilateral teleoperation system with asymmetric time-varying delays. The stability is analyzed by the Lyapunov–Krasovskii function and the delay-dependent stability criteria are obtained under linear-matrix-inequalities conditions. Third, a vision-based localization is presented to calibrate the UAV’s pose and provide the relative distance for obstacle avoidance with a high accuracy. Finally, the performance of the teleoperation scheme is evaluated by both human-in-the-loop simulations and real-time experiments where a single UAV flies through the obstructed environment.

Experimental results demonstrate that the teleoperation system can maintain passivity and collision avoidance can be achieved with a high accuracy for asymmetric time-varying delays. Moreover, the operator could tele-sense the force reflection to improve the maneuverability in the aerial teleoperation.

A real-time bilateral teleoperation system of a UAV for collision avoidance is performed in the laboratory. A force and visual interface is designed to provide force and visual feedback of the slave environment to the operator.

This paper aims to present a fully actuated aerial manipulator (AM) with a robust motion/force hybrid controller for conducting contact-typed inspection tasks in industrial plants.

An AM is designed based on a hexarotor with tilted rotors and a rigidly attached end effector. By tilting the rotors, the position and attitude of the AM can be controlled independently, and the AM can actively exert forces on industrial facilities through the rigidly attached end effector. A motion/force hybrid controller is proposed to perform contact-typed inspection tasks. The contact-typed inspection task is divided into the approach phase and the contact phase. In the approach phase, the AM automatically approaches the contact surface. In the contact phase, a motion/force hybrid controller is used for contact-typed inspection. Finally, a disturbance observer (DOB) is used to estimate external disturbances and used as feedforward compensation.

The proposed AM can slowly approach the contact surface without significant impact in the contact phase. It can realize constant force control in the direction normal to the contact surface in the contact phase, whereas the motion of the remaining directions can be controlled by the operator. The use of the DOB ensures the robustness of the AM in the presence of external wind disturbances.

A fully actuated AM system with a robust motion/force hybrid controller is proposed. The effectiveness of the proposed AM system for conducting contact-typed industrial inspection tasks is validated by practical experiments.

This paper seeks to study the feasibility of a stator vibration damping using piezoelectric (PZT) actuators applied to switched reluctance motors (SRM).

A single‐phase structure without moving rotor, but with the same shape as an SRM stator, is introduced to simplify the study and the experimental measurements. Both analytical and finite element methods are used to detail the chosen location and design of the PZT actuators for this structure.

Experimental results show that PZT actuators with a low voltage allow the decrease of the vibration level due to the electromagnetic forces.

To decrease the vibration level of the SRM stator in the real use of the machine, a closed loop system is necessary. Future works consist of the design of a closed loop numerical controller using an acceleration sensor as strain information.

The proposed damping method gives a new solution for the SRM noise problem that can be useful for people working on noise reduction on this machine.

So far vibration damping of SRM stator was obtained using a command or a geometry “acoustically” optimised, or active vibration with an auxiliary coil. The solution presented here applies PZT vibration damping to the stator with a thickness more important than the one of classical plates used for PZT damping applications.

This paper aims to use the adaptive computed torque control (ACTC) method to eliminate the kinematic and dynamic uncertainties of master and slave robots and for the control of the system in the presence of forces originating from human and environment interaction.

In case of uncertainties in the robot parameters that are utilized in teleoperation studies and when the environment where interactions take place is not known and when there is a time delay, very serious problems take place in system performance. An adaptation rule was created to update uncertain parameters. In addition to this, disturbance observer was designed for slave robot. Lyapunov function was used to analyze the system’s position tracking and stability. A visual interface was designed to ensure that the movements of the master robot provided a visual feedback to the user.

In this study, a visual interface was created, and position and velocity control was achieved utilizing teleoperation; the system’s position tracking and stability were analyzed using the Lyapunov method; a simulation was applied in a real-time environment, and the performance results were analyzed.

This study consisted of both simulation and real-time studies. The teleoperation system, which was created in a laboratory environment, consisted of six-degree-of-freedom (DOF) master robots, six-DOF industrial robots and six-DOF virtual robots.

The purpose of this paper is to achieve high‐performance aerofoils that enable delayed stall conditions and achieve high lift to drag ratios.

The unsteady Reynolds averaged Navier‐Stokes equations are employed in conjunction with a shear stress transport (κ‐ω) turbulence model. A control equation is designed and implemented to determine the temporal response of the actuator. A rotating element, in the form of an actuator disc, is embedded on the leading edge of NACA 0012 aerofoil, to inject momentum into the wake region. The actuator disc is rotated at different angular speeds, for angles of attack (α) between 00 and 240.

Phenomena such as flow separation, wake vortices, delayed stall, wake control, etc. are numerically investigated by means of streamlines, streaklines, isobars, etc. Streamwise and cross‐stream forces on the aerofoil are obtained. The influence of momentum injection parameter (ξ) on the fluid flow patterns, and hence on the forces acting on the streamlined body are determined. A synchronization‐based coupling scheme is designed and implemented to achieve annihilation of wake vortices. A delayed stall angle resulted with an attendant increase in maximum lift coefficient. Due to delay and/or prevention of separation, drag coefficient is also reduced considerably, resulting in a high‐performance lifting surface.

The practicality of momentum injection principle requires both wide ranging and intensive further studies to move forward beyond the proof of concept stage.

Determination of forces and moments on an aerofoil is of vital interest in aero‐dynamic design. Perhaps, runways of the future can be shorter and/or more pay load can be carried by an aircraft, for the same stall speed.

The paper describes how a synchronization‐based coupling scheme is designed and implemented along with the RANS solver. Furthermore, it is tested to verify the dynamic adaptability of the wake vortex annihilation for NACA 0012 aerofoils.

To design an optimal active shield for the mitigation of the magnetic stray field around an induction heating device.

The active shield consists of several compensation coils in series and generates a counter field opposite to the main field. One extra compensation winding – the “generating compensation winding” (GCW) – is positioned close to the excitation coil and works as the secondary winding of a transformer. The power in this winding is used to drive the other compensation coils (the active shield), which are the load of the transformer. A circuit with passive components is inserted between the GCW and the other compensation coils. The shield is optimal if it achieves a high field reduction, while the energy dissipation is low. By using a genetic algorithm (GA) that minimizes an objective function, the optimization algorithm finds the optimal geometry and the optimal current for the GCW and the other compensation coils. The objective function uses time harmonic and axisymmetric finite element calculations.

The transformer driven active shield reduces the magnetic field effectively. It is cheap and easy to build, but it works well only for one frequency.

The shield is sensitive to tuning of the passive circuit and to changes in the frequency of the induction heater.

This transformer driven shield is an alternative for the classical active shield with external power supply.

An active shield that does not need an external power supply is a cheap solution for the shielding of magnetic fields.

INDUSTRIAL consultants are being increasingly employed both here and in the United States. It is natural that much of their work should fall within the field of work study since the usual reason for calling them in is to secure greater productivity. Such incursions are sometimes looked at askance by those assigned to that particular role in a company. This understandable human attitude will not be exorcised by implying that consultants are a race of infallible beings whose job is to impose superior methods on the permanent staff.