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The purpose of this paper is to propose a combination bank-to-turn control mode with the single moving mass and reaction jet and design the roll control law for the long-range reentry maneuverable warhead.

Based on the dynamics model of this new control mode, the control model of roll channel is converted into a perturbed double-integrator system. The on-off optimal feedback control law is designed on the phase plane formed by Euler angle error and angular velocity error. To weaken the “on-off chattering” that is generated near the origin of the phase-plane and effectively reduce the jet fuel consumption for stability control, an on-off control outer ring and an inner ring are introduced into the phase plane.

This control mode can not only avoid the aerodynamic rudder ablation to improve the efficiency of attitude control, but also reduce the fuel consumption of jet control by using moving mass control. The simulation results indicate that the designed control law can meet the speediness and robustness requirements of the long-range maneuverable warhead controlled by the single moving mass and reaction jet. This measure can also eliminate the on-off chattering effectively.

The new control mode solves some engineering problems of long-range reentry maneuverable warhead controlled by only one actuator. The control mode has a promising prospect in engineering practice.

The paper provides a new control mode and a combination control strategy, and designs an effective control law.

This paper aims to present the impact analysis of payload rendezvous with tethered satellite system and the design of an adaptive sliding mode controller which can deal with mass parameter uncertainty of targeted payload, so that the proposed cislunar transportation scheme with spinning tether system could be extended to a wider and more practical range.

In this work, dynamical model is first derived based on Langrangian equations to describe the motion of a spinning tether system in an arbitrary Keplerian orbit, which takes the mass of spacecraft, tether and payload into account. Orbital design and optimal open-loop control for the payload tossed by the spinning tether system are then presented. The real payload rendezvous impact around docking point is also analyzed. Based on reference acceleration trajectory given by optimal theories, a sliding mode controller with saturation functions is designed in the close-loop control of payload tossing stage under initial disturbance caused by actual rendezvous error. To alleviate the influence of inaccurate/unknown payload mass parameters, the adaptive law is designed and integrated into sliding mode controller. Finally, the performance of the proposed controller is evaluated using simulations. Simulation results validate that proposed controller is found effective in driving the spinning tether system to carry payload into desired cislunar transfer orbit and in dealing with payload mass parameter uncertainty in a relatively large range.

The results show that unideal rendezvous manoeuvres have significant impact on in-plane motion of spinning tether system, and the proposed adaptive sliding mode controller with saturation functions not only guarantees the stability but also provides good performance and robustness against the parameter and unstructured uncertainties.

This work addresses the analysis of actual impact on spinning tether system motion when payload is docking with system within tolerated docking window, rather than at the particular ideal docking point, and the robust tracking control of deep-space payload tossing missions with the spinning tether system using the adaptive sliding mode controller dealing with parameter uncertainties. This combination has not been proposed before for tracking control of multivariable spinning tether systems.

In the need to optimize the energy efficiency, control structures can have a positive effect by tracking the optimal operating point according to the speed and mechanical load of the motor. The purpose of this paper is to present an energy-efficient scalar control for squirrel-cage induction motors (IMs), taking into consideration the effect of core losses.

The proposed technique is based on the modification of the stator flux reference, to track the best efficiency point. The optimal flux values are computed through an improved model of the IM including core losses, then stored in a look-up table.

Simulations of the proposed scalar control are carried out, and results show the efficiency improvement when the flux is optimized especially at low load cases. Results were validated experimentally on two motors compliant with different efficiency standards.

The proposed approach can be used in several fields and applications using the scalar-controlled IM with a proper implementation in variable speed drives, as in the cases of pumps, compressors and blowers.

The proposed technique is compared to existing optimization methods in literature, and the results show an improvement in the dynamic performance and in the response delays. The approach is also compared to an optimization technique used in industries like Leroy-Somer for variable speed drives, and efficiency improvements are shown.

The subject of the paper is the mechatronic design of a novel robotic hand, cassino-underactuated-multifinger-hand (Ca.U.M.Ha.), along with its prototype and the experimental analysis of its grasping of soft and rigid objects with different shapes, sizes and materials. The paper aims to discuss these issues.

Ca.U.M.Ha. is designed with four identical underactuated fingers and an opposing thumb, all joined to a rigid palm and actuated by means of double-acting pneumatic cylinders. In particular, each underactuated finger with three phalanxes and one actuator is able to grasp cylindrical objects with different shapes and sizes, while the common electropneumatic operation of the four underactuated fingers gives an additional auto-adaptability to grasp objects with irregular shapes. Moreover, the actuating force control is allowed by a closed-loop pressure control within the pushing chambers of the pneumatic cylinders of the four underactuated fingers, because of a pair of two-way/two-position pulse-width-modulation (PWM) modulated pneumatic digital valves, which can also be operated under ON/OFF modes.

The grasping of soft and rigid objects with different shapes, sizes and materials is a very difficult task that requires a complex mechatronic design, as proposed and developed worldwide, while Ca.U.M.Ha. offers these performances through only a single ON/OFF or analogue signal.

Ca.U.M.Ha. could find several practical applications in industrial environments since it is characterized by a robust and low-cost mechatronic design, flexibility and easy control, which are based on the use of easy-running components.

Ca.U.M.Ha. shows a novel mechatronic design that is based on a robust mechanical design and an easy operation and control with high dexterity and reliability to perform a safe grasp of objects with different shapes, sizes and materials.

To achieve a full understanding of the role of marketing from plan to profit requires a knowledge of the basic building blocks. This textbook introduces the key concepts in the art or science of marketing to practising managers. Understanding your customers and consumers, the 4 Ps (Product, Place, Price and Promotion) provides the basic tools for effective marketing. Deploying your resources and informing your managerial decision making is dealt with in Unit VII introducing marketing intelligence, competition, budgeting and organisational issues. The logical conclusion of this effort is achieving sales and the particular techniques involved are explored in the final section.

The aim of this paper is to discuss E-sail-based missions (E-sail – electric solar wind sail) towards Venus and Mars. The analysis takes into account the real three-dimensional shape of the starting and arrival orbits and the planetary ephemeris constraints by using the Jet Propulsion Laboratory (JPL) planetary ephemerides model DE405/LE405.

Each mission scenario is parameterized with different values of departure date and spacecraft characteristic acceleration, the latter representing the maximum propulsive acceleration when the Sun–spacecraft distance is 1 au. The transfer trajectories are studied in an optimal framework, using a Gauss pseudospectral method in which the initial guesses for the state and control histories are obtained with a genetic algorithm-based approach.

The paper illustrates the numerical simulations obtained with a spacecraft characteristic acceleration of 1 mm/s², and the results cover a range of launch dates of 17 years for both Earth–Mars and Earth–Venus interplanetary missions. In particular, the numerical results confirm the competitiveness of such a propellantless propulsion system.

A parametric study of the transfer’s flight time corresponding to the optimal departure dates is discussed for different values of the spacecraft characteristic acceleration. The results motivate a further in-depth analysis of the E-sail concept.

This paper extends previous work on optimal trajectories with an E-sail in that the best launch opportunities are investigated. A refined thrust model is also used in all numerical simulations.

Ranulph Glanville has argued that ambitions of strict control are misplaced in epistemic processes such as learning and designing. Among other reasons, he has presented quantitative arguments for this ethical position. As a part of these arguments, Glanville claimed that strict control even of modest systems transcends the computational limits of our planet. The purpose of this paper is to review the related discourse and to examine the soundness of this claim.

Related literature is reviewed and pertinent lines of reasoning are illustrated and critically examined using examples and straightforward language.

The claim that even modest epistemic processes transcend the computational means of our planet is challenged. The recommendation to assume out-of-control postures in epistemic processes, however, is maintained on ethical rather than on quantitative grounds.

The presented reasoning is limited in as far as it is ultimately based on an ethical standpoint.

This paper summarizes an important cybernetic discourse and dispels the notion therein that epistemic processes necessarily involve computational demands of astronomical proportions. Furthermore, this paper presents a rare discussion of Glanville’s Corollary of Ashby’s Law of Requisite Variety.

This paper aims to present the control laws to be used in the control of pendular motion on tethered satellite systems in space during orbiting by using a nonlinear design technique.

This work presents both physical and mathematical models represented in a circular orbit. Euler equation of the rigid body is applied under reasonable assumption so as to form the equations of pendular motion. These equations are then used to develop the control laws using a nonlinear design technique. The control laws are required to drive the in-plane angles and out-of-plane angles of the pendular motion to the required trajectories. Simulations are then conducted to study the control results.

Simulation results show that the control laws in both plane angles of motions considered are able to move the pendular motion to the required trajectory. It was also eminent that a lot of effort is required in the case of the reference trajectory that corresponds to the constant inside-plane. To control the pendular motion of the plane, one requires an extended period of time and it should be controlled within a reasonable range. In the outside-of-plane pendular motion, minimal or no effort is required for the control. The reason is that the trajectory is natural planar.

This research is expected to provide a dynamic control strategy for all tethered satellite space systems.

The research proposes a combined dynamic method for the purpose of improving the control of all types of tether satellites.

The librarian and researcher have to be able to uncover specific articles in their areas of interest. This Bibliography is designed to help. Volume IV, like Volume III, contains features to help the reader to retrieve relevant literature from MCB University Press' considerable output. Each entry within has been indexed according to author(s) and the Fifth Edition of the SCIMP/SCAMP Thesaurus. The latter thus provides a full subject index to facilitate rapid retrieval. Each article or book is assigned its own unique number and this is used in both the subject and author index. This Volume indexes 29 journals indicating the depth, coverage and expansion of MCB's portfolio.