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Claimed to be programmable logic controllers (PLCs) that act like distributed control systems (DCSs), various people define hybrid systems differently: by functions, by industries served, by architecture, and even by no label at all. As a result, there is still confusion about the label “Hybrid Systems.” This paper aims to explore these issues briefly and to help understand and reduce confusion about these relatively recent hybrid systems, which are now also being called “Programmable Automation Controls” (PAC).

The paper compares DCSs, PLCs, centralized computer systems, use of industrial professional (personal) computers, original hybrid control systems, current hybrid control systems, evolution to PAC and shows evolution of new programming standards.

Hybrid control systems can readily become part of the overall plant productivity. This is a stepping‐stone towards complete enterprise control systems.

No small part of this capability is the emerging standard for easy consistent configuration of hybrid systems, regardless of the vendor who supplies them.

Because of the emerging configuration standard, the hybrid system can be re‐configured as needed due to plant changes or market swing. This provides the user with “agile manufacturing.”

More than a “cheap DCS,” these hybrid control systems can be an inexpensive stepping‐stone towards managing the business as it was meant to be managed. What is important is that these elements can be introduced in manageable increments to meet tight budgets.

Sensorless interior permanent magnet in-wheel motor (IPMIWM), as an exemplar of modular automation system, has attracted considerable interests in recent years. This paper aims to investigate a novel hybrid control approach for the sensorless IPMIWM from a cyber-physical systems (CPS) perspective.

The control approach is presented based on the hybrid dynamical theory. In the standstill-low (S-L) speed, the rotor position/speed signal is estimated by the method of the high frequency (HF) voltage signal injection. The least square support vector machine (LS-SVM) is used to acquire the rotor position/speed signal in medium-high (M-H) speed operation. Hybrid automata model of the IPMIWM is established due to its hybrid dynamic characteristics in wide speed range. A hybrid state observer (HSO), including a discrete state observer (DSO) and a continuous state observer (CSO), is designed for rotor position/speed estimation of the IPMIWM.

The hardware-in-the-loop testing based on dSPACE is carried out on the test bench. Experimental investigations demonstrate the hybrid control approach can not only identify the rotor position/speed signal with a certain load but also be able to reject the load disturbance. The reliability and the effectiveness of the proposed hybrid control approach were verified.

The proposed hybrid control approach for the sensorless IPMIWM promotes the deep combination and coordination of sensorless IPMIWM drive system. It also theoretically supports and extends the development of the hybrid control of the highly integrated modular automation system.

While prior control studies typically focus on organizations with an instrumental approach to corporate sustainability, this study concentrates on organizations with an integrative approach, as the latter is needed to address the grand challenge of sustainable development. As such organizations do not single out the financial objective as the dominant one, they pursue a hybrid mission. This study investigates how a control package can be designed that ensures the persistence of such a hybrid mission.

A case study is undertaken at a luxury hotel chain in which a financial and an environmental objective are continuously balanced. Self-determination theory is used to substantiate insights into how psychological need-supportive controls can be designed at all organizational levels.

This study highlights how controls are not only needed to direct staff behaviour towards the environmental objective but also to ensure that staff at all organizational levels prioritize the objectives in such way that the hybrid mission can be sustained. Besides structural differentiation and centralization of decision-making, the case organization designed need-supportive controls to foster staff's internalization of the environmental objective and value as well as of the integrative approach.

As the need-supportive socialization process fostered staff's integration of the environmental value, this study highlights the transformational potential of controls.

This study provides a unique account of a control package directing staff behaviour towards the balancing of multiple objectives.

Shop floor control systems are generally major points of discussion in production planning and control literature. The purpose of this paper is to investigate how lean production control principles can be used in a make-to-order (MTO) job shop, where the volume is typically low and there is high variety. This paper examines the procedures involved in implementing a constant work-in-process (CONWIP)/Kanban hybrid system in the shop floor environment and also provides insights and guidelines on the implementation of a hybrid system in a high-variety/low-volume environment.

The authors review literature on Kanban, CONWIP, and CONWIP/Kanban hybrid systems to analyze how lean production control principles can be used in a MTO job shop. The second part focuses on the process of implementation. Using a case study of a manufacturer of electromechanical components for valve monitoring and controls, the paper describes how the operation is transformed by for more efficient shop floor control systems. Real experiments are used to compare pre- and post-improvement performance.

The study shows that the proposed hybrid Kanban-CONWIP system reduced the cycle time and achieved an increase of 38 percent in inventory turnover. The empirical results from this pilot study provide useful managerial insights for a benchmarking analysis of the actions to be taken into consideration by companies that have similar manufacturing systems.

The statistic generalization of the results is impossible due to the use of a single case method of study.

This paper provides insights and guidelines on the implementation of a hybrid system in a high-variety/low-volume environment. The literature on real applications of hybrid CONWIP/Kanban by case study is limited.

MRP is a priority‐planning technique, not an execution tool. Waste can be avoided through the use of JIT as an execution tool, where only those materials which are actually needed on the factory floor are “pulled”, when they are needed. Describes a hybrid manufacturing system which incorporates the traditional MRP system and the Japanese JIT system in a single framework. The rationale is not whether MRP or JIT is better; it is how they complement each other in a hybrid system. Specifically, this framework attempts to integrate both MRP and JIT production. The integrated hybrid system can provide better production planning, scheduling and control. It employs the logic of MRP and JIT, but it eliminates some of the inherent problems and drawbacks in both systems.

This paper aims to solve the problems of the synchronization between branches and the uncertainties such as joint friction, load variation and external interference of a hybrid mechanism. The controller is used to improve the synchronization and robustness of the hybrid mechanism system and achieve both finite time convergence and chattering-free sliding mode.

First, the dynamic model of hybrid mechanism containing lumped uncertainties is formulated by the Lagrange method, and a composite error based on coupling synchronization error and the end-effector tracking error is set up in the task space. Then, by combining the finite time super twisting sliding mode control algorithm, a composite error-based finite time super twisting sliding mode synchronous control law is designed to make the end-effector tracking error and coupling synchronization error achieve better tracking performance and convergence performance. Finally, the Lyapunov stability of the control law and the finite-time convergence of the composite error are proved theoretically.

To verify the effectiveness of the proposed control method, simulations and experiments for the prototype system of the hybrid mechanism are conducted. The results show that the proposed control method can achieve better tracking performance and convergence performance.

This is a new innovation for a hybrid mechanism containing lumped uncertainties to improve the robustness, convergence performance, tracking performance and synchronization of the system.

The purpose of this study is to present a novel hybrid closed-loop control method together with its performance validation for the dexterous prosthetic hand.

The hybrid closed-loop control is composed of a high-level closed-loop control with the user in the closed loop and a low-level closed-loop control for the direct robot motion control. The authors construct the high-level control loop by using electromyography (EMG)-based human motion intent decoding and electrical stimulation (ES)-based sensory feedback. The human motion intent is decoded by a finite state machine, which can achieve both the patterned motion control and the proportional force control. The sensory feedback is in the form of transcutaneous electrical nerve stimulation (TENS) with spatial-frequency modulation. To suppress the TENS interfering noise, the authors propose biphasic TENS to concentrate the stimulation current and the variable step-size least mean square adaptive filter to cancel the noise. Eight subjects participated in the validation experiments, including pattern selection and egg grasping tasks, to investigate the feasibility of the hybrid closed-loop control in clinical use.

The proposed noise cancellation method largely reduces the ES noise artifacts in the EMG electrodes by 18.5 dB on average. Compared with the open-loop control, the proposed hybrid closed-loop control method significantly improves both the pattern selection efficiency and the egg grasping success rate, both in blind operating scenarios (improved by 1.86 s, p < 0.001, and 63.7 per cent, p < 0.001) or in common operating scenarios (improved by 0.49 s, p = 0.008, and 41.3 per cent, p < 0.001).

The proposed hybrid closed-loop control method can be implemented on a prosthetic hand to improve the operation efficiency and accuracy for fragile objects such as eggs.

The primary contribution is the proposal of the hybrid closed-loop control, the spatial-frequency modulation method for the sensory feedback and the noise cancellation method for the integrating of the myoelectric control and the ES-based sensory feedback.

In addressing policy problems, it is difficult to disentangle public policies from private efforts, business institutions and civic activities. Societies may acknowledge that all these domains have a role in accomplishing social aims, but there are fundamental problems in understanding why, how and with what implications this occurs. Drawing upon the insights from the papers of this special issue, the authors aim to advance the understanding of governance and accountability in different contexts of hybridity, hybrid governance and organizations.

The authors conceptualize common theoretical origins of hybrid organizations and the ways in which they create and enact value by reflecting on the articles of the special issue. Furthermore, the authors propose agendas for future research into hybrid organizations.

Hybrid organizations can be conceptualized through two types of lenses: (1) the dimensions of hybridity (ownership, institutional logics, funding and control) and (2) their approaches to value creation (mixing, compromising and legitimizing).

This article provides more detailed and comprehensive understanding of hybridity. This contribution has also important practical implications for actors, such as politicians, managers, street-level bureaucrats, professionals, auditors and accountants who may be enveloped in various hybrid settings, policy contexts and multi-faceted interfaces between public, private and the civil society sector.

Hybridity lenses reveal novel connections between four types of hybrid institutional contexts: state-owned enterprises (SOEs), non-profit organizations (NPOs), social enterprises (SEs) and municipally owned corporations (MOCs). This paper provides theoretical instruments for doing so.

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 paper aims to present a smooth transition adaptive hybrid impedance control for compliant connector assembly.

The dynamics of the manipulator is firstly presented with linear property. The controller used in connector assembly is inspired by human operation habits in similar tasks. The hybrid impedance control is adopted to apply force in the assembly direction and provide compliance in rest directions. The reference trajectory is implemented with an adaptive controller. Event-based switching strategy is conducted for a smooth transition from unconstrained to constrained space.

The method can ensure both ideal compliance behaviour with dynamic uncertainty and a smooth transition from unconstrained to constrained space. Also, the method can ensure compliant connector assembly with a good tolerance to the target estimation error.

The method can be applied in the connector assembly by “pushing” operation. The controller devotes efforts on force tracking and smooth transition, having potential applications in contact tasks in delicate environment.

As far as the authors know, the paper is original in providing a uniform controller for improving force and position control performance in both unconstrained and constrained space with dynamic uncertainty. The proposed controller can ensure a smooth transition by only adjusting parameters.