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Aiming at the positioning accuracy control problem in the running of the assembly machine for assembled camshaft, a kind of position controller based on the feedforward‐feedback control of speed and acceleration is designed.

It combines feedforward‐feedback control with the quartic displacement curve acceleration/deceleration algorithm.

The axial dimension and the phase angle of the cam obtained after being assembled is checked. The result shows that for each type of camshaft, the error of the axial dimension of the cam is less than ±0.2mm and the error of the phase angle of the cam is less than ±30′. In addition, production efficiency is greatly improved (the assembling time is 90‐120S/piece).

The paper combines feedforward‐feedback control with the quartic displacement curve acceleration/deceleration algorithm for the first time.

Argues that in increasingly turbulent and complex environments, the tools of “systems thinking” may provide a valuable resource in the drive to attain integration between strategic and operational objectives. Particular examples in the domain of production control and supply‐chain management are presented as illustrations of the dynamicist’s paradigm. Hence it is suggested that familiar concepts such as JIT/Kanban and supply chains are actually special cases of generic feedback control principles, while pure MRP is a classic example of feedforward. In practice, the complexities of real world operations require combinations of these two approaches and the paper therefore assesses the implications of these theoretical concepts, for the design of practical operations systems.

Based on the inverse kinematics and task space dynamic model, this paper aims to design a high-precision trajectory tracking controller for a 2-DoF translational parallel manipulator (TPM) driven by linear motors.

The task space dynamic model of a 2-DoF TPM is derived using Lagrangian equation of the first type. A task space dynamic model-based feedforward controller (MFC) is designed, which is combined with a cascade PID/PI controller and velocity feedforward controller (VFC) to construct a hybrid PID/PI+VFC/MFC controller. The hybrid controller is implemented in MATLAB/dSPACE real-time control platform. Experiment results are given to validate the effectiveness and industrial applicability of the hybrid controller.

The MFC can compensate for the nonlinear dynamic characteristics of a 2-DoF TPM and achieve better tracking performance than the conventional acceleration feedforward controller (AFC).

The task space dynamic model-based hybrid PID/PI+VFC/MFC controller is proposed for a 2-DoF linear-motor-driven TPM, which reduces the tracking error by at least 15 percent compared with conventional hybrid PID/PI+VFC/AFC controller. This control scheme can be extended to high-speed and high-precision trajectory tracking control of other parallel manipulators by reprogramming the feedforward signals of traditional cascade PID/PI controller.

This study aims to empirically examine the effects of using the management control system (MCS) on individual performance mediated by organizational learning. Complementarily, it evaluates the moderating effect of feedforward on the relationship between MCS use and organizational learning.

Structural equation modeling and mediation and moderation analyses were used in a sample of 194 managers from Brazilian companies listed in the Exame Magazine’s “Best and Biggest” ranking.

The results reveal that using the MCS from a cybernetic perspective contributes to organizational learning, contradicting theoretical arguments and empirical evidence that this hinders learning and that feedforward can strengthen this relationship, as long as it is in line with the way of using the MCS. A mediating effect of organizational learning on the relationship between MCS use and individual performance has also been confirmed.

The results demonstrate the effects of MCS use on individual performance and organizational learning by taking a taxonomy of cybernetic use and comprehensive MCS use as a basis. The results provide insights to managers by revealing that MCS use not only influences task performance through organizational learning but also tends to generate cooperative, persistent and initiative-taking behaviors.

The study provides an approach to the behavioral consequences of using the MCS (score-keeping use and comprehensive MCS use) and the role of specific cognitive and motivational mechanisms in individual performance from a multidimensional perspective (task-based, contextual and general).

The purpose of this study is to propose a torque vectoring control system for improving the handling stability of distributed drive electric buses under complicated driving conditions. Energy crisis and environment pollution are two key pressing issues faced by mankind. Pure electric buses are recognized as the effective method to solve the problems. Distributed drive electric buses (DDEBs) as an emerging mode of pure electric buses are attracting intense research interests around the world. Compared with the central driven electric buses, DDEB is able to control the driving and braking torque of each wheel individually and accurately to significantly enhance the handling stability. Therefore, the torque vectoring control (TVC) system is proposed to allocate the driving torque among four wheels reasonably to improve the handling stability of DDEBs.

The proposed TVC system is designed based on hierarchical control. The upper layer is direct yaw moment controller based on feedforward and feedback control. The feedforward control algorithm is designed to calculate the desired steady-state yaw moment based on the steering wheel angle and the longitudinal velocity. The feedback control is anti-windup sliding mode control algorithm, which takes the errors between actual and reference yaw rate as the control variables. The lower layer is torque allocation controller, including economical torque allocation control algorithm and optimal torque allocation control algorithm.

The steady static circular test has been carried out to demonstrate the effectiveness and control effort of the proposed TVC system. Compared with the field experiment results of tested bus with TVC system and without TVC system, the slip angle of tested bus with TVC system is much less than without TVC. And the actual yaw rate of tested bus with TVC system is able to track the reference yaw rate completely. The experiment results demonstrate that the TVC system has a remarkable performance in the real practice and improve the handling stability effectively.

In view of the large load transfer, the strong coupling characteristics of tire , the suspension and the steering system during coach corning, the vehicle reference steering characteristics is defined considering vehicle nonlinear characteristics and the feedforward term of torque vectoring control at different steering angles and speeds is designed. Meanwhile, in order to improve the robustness of controller, an anti-integral saturation sliding mode variable structure control algorithm is proposed as the feedback term of torque vectoring control.

This study aims to examine the feasibility of feedforward actuation of the recoater blade position to alleviate the resin surface non-uniformity while moving over deep-to-shallow transitions of submerged (already cured) geometric features.

A two-dimensional computational fluid dynamics (CFD) model has been used to determine optimized blade actuation protocols to minimize the resin surface non-uniformity. An experimental setup has been designed to validate the feasibility of the proposed protocol in practice.

A developed protocol for the blade height actuation is applied to a rectangular stair-like configuration of the underlying part geometry. The evaluation of the actuation protocol revealed the importance of two physical length scales, the capillary length and the size of the flow recirculation cell below in the liquid resin layer below the blade. They determine, together with the length scales defining the topography (horizontal extent and depth), the optimal blade trajectory. This protocol has also shown its efficiency for application to more complicated shapes (and, potentially, for any arbitrary geometry).

This study shows that incorporation of a feedforward control scheme in the recoating system might significantly reduce (by up to 80%) the surface unevenness. Moreover, this improvement of performances does not require major modifications of the existing architecture.

The results presented in this work demonstrate the benefits of the integration of the feedforward control to minimize the leading edge bulges over underlying part geometries in stereolithography.

The corporate board of directors is a body entrusted with power to make economic decisions affecting the well‐being of investors' capital, employees' security, communities' economic health, and executives’ power and perquisites. The power of the board of directors is often forgotten in this complex society. Managers, the government, and special interest groups seem to impose upon the corporation situations that are never addressed by the board of directors. Yet it is the board that has the ultimate internal authority within the corporation. Corporate charters granted by the various states specifically assign to the board of directors the responsibility of management, or the delegation of that management. The directors act as trustees for the shareholders, selecting the management structure of the firm, and delegating to that management structure those administrative matters the board itself chooses. The degree of delegation is a decision of each board, with most boards delegating away the major portion of their decision‐making authority.

In this paper, a coordinated attitude control law for a tracking and data relay satellite (TDRS) with mobile antennas is proposed. To track or point the target spacecraft with median/law orbit, the large mobile antennas have to move in a wide range, the movement of such mobile antennas disturbing the satellite attitude. Conventionally, the main body of the satellite and the mobile antennas are controlled independently. The proposed controller first estimates the TDRS's angular momentum which the mobile antennas will produce, based on the momentum conservation equation, then adds the estimated angular momentum as a feedforward signal to the conventional control law. The proposed controller is demonstrated using mathematical simulation, the results of which coincide well with analytical results.

Aims to realize the high accurate contour control with high‐speed motion of articulated robot manipulator (ARM) with interference.

Proposes a new contour control method by using Gaussian neural network (GNN) to solve the problem of the deterioration of the contour control performance due to the interference between robot links. The construction of the GNN controller and the approximation of the interference are based on the Euler‐Lagrange model of ARM. The actual input/out data about the motion of ARM are used for training the GNN to accurately represent the inverse dynamics of ARM with interference. With the Lyapunov function, the stability and the robustness of the GNN controller are discussed. Through the simulation and experiment, it verified that the precision of the contour control has been improved, and illustrated the good features of the proposed method.

Finds that the actual data about the motion of ARM, which is easily obtained from the working field, can express the real features of ARM, and the GNN controller can improve the precision of the contour control with good features.

The proposed method provides an effective method for realizing high accurate contour control of ARM with interference. It can be extended to the ARMs with more than two links and concerning more factors affecting the precision of the contour control, such as friction or gravity.

Proposes a new GNN controller for realizing high accurate contour control of ARM with interference, which is significant for industry.

Many of the traditional controls that accountants and auditors are most familiar with can be traced to bureaucratic management. This article introduces a business process control model that fully captures the broader array of process controls now being implemented by world‐class organizations, including value‐adding controls focused on quality, cost and time. The article describes the categories of controls included in the model, presents a new way of mapping process controls that reflects the model, and illustrates the use of the model within the context of an actual business process. The article also discusses the primary benefits of adopting the model. First, the model provides a common business process control language and structure which will facilitate communications and foster a uniform understanding of process controls among senior executives, process owners, accountants and auditors. Second, the model provides a framework for comprehensively assessing business process risks and evaluating and improving business process controls.