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The Pallet Handling Device (PHD) is a five degree‐of‐freedom (dof) robot system under development by Stewart‐Glapat Corporation for autonomous loading of pallets into semi‐truck trailers at loading docks. The fully‐autonomous control is achieved using a programmable logic controller (PLC) and sensors. Ohio University has developed a one‐eighth‐scale prototype hardware system for PHD controls implementation and evaluation. This article describes the design and construction of this system, including the control architecture and PLC programming. The main objective of the scale hardware prototype is to demonstrate the autonomous control feasibility of the proposed full‐scale PHD system; this cannot be adequately performed in simulation.

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.

This paper presents an overview on the Auto‐ID (Automatic Identification) technologies testbed that has been established at the University of Missouri‐Rolla (UMR) with the objective of supporting research, development, and implementation of Auto‐ID technologies in network‐centric manufacturing environments.

UMR's Auto‐ID testbed uses a unique hardware‐in‐the‐loop simulation methodology, which integrates decision‐making model development with the design of networking topology and data routing/scheduling schemes, in order to develop, test, and implement viable Auto‐ID solutions. The methodology is founded on a 3‐level integrated model: controller simulation, distributed controller simulation, and distributed controller simulation with hardware‐in‐the‐loop.

This paper discusses two case studies that highlight the effective use of RFID technology, its potential advantages, challenges, and deficiencies stemming from particular applications. These applications include dock doors, automated guided vehicles, conveyor and automated storage/retrieval systems, integration of RFID middleware with programmable logic controllers, and inventory management of time‐sensitive materials.

The paper presents an innovative idea: hardware‐in‐the‐loop simulation methodology to design automation systems. The approach has been implemented on a variety of applications, which are presented in the paper as case studies.

This paper describes the design and development of a re‐configurable dual‐robot assembly system using off‐the‐shelf re‐configurable pneumatic modules, Hall‐effect sensors, a vision system, and a programmable logic controller (PLC). Each robot arm consists of three sets of pneumatic modules and a pneumatic gripper. Each module consists of a pneumatic housing, an air cylinder, and a Hall‐effect sensor, and provides one degree of freedom. Solenoids are used to redirect airflow and thereby extend and/or retract the air cylinder. A vision system is used for fixture inspection. A conveyor and part stopper are designed to transfer and stop pallets. All these modules, the gripper, the part stopper, and the vision system are controlled and synchronized using a PLC. At the end of this paper, a framework for making the system over the Web for remote operation and diagnosis is proposed and described.

The purpose of this paper is to study a woodworking machine, in which a linear induction motor (LIM) is applied to feed the wood to be processed into the cutting saw. The LIM is optimally designed and the whole drive system is controlled by a programmable logic controller (PLC) to meet the industrial demands.

Since the operation range is short, the LIM mainly works at the transient state of quick start and quick brake. Hence, the thrust force with a large slip ratio (hereafter called the starting thrust) is one of the most important issues in the LIM design. Finite element method is used to optimize the starting thrust while taking a specific variable voltage variable frequency (VVVF) drive into account.

The LIM system directly drives the machine workbench where the wood is placed, eliminating the requirement of manpower to push the wood through the cutting saw, hence, greatly reduces the operation hazard. It has a higher reliability and longer service life than the conventional drive system employing a rotary motor with a ball screw mechanism.

The LIM is an attractive candidate for the woodworking machine application, which can replace the complicated and relatively low-efficiency mechanism of rotary motor and ball screw. High starting thrust can be achieved by optimizing the LIM design, whilst the specific VVVF control is essential to ensure a good drive performance. The PLC is competent for both human-machine interface (HMI) and control of the inverter-fed LIM system, and is of high reliability in industrial environment.

Chemical processes, employed for manufacturing basic chemicals are highly energy intensive. Due to escalating costs of fossil fuels and capacity addition, the electricity cost has been increasing for the last few decades. Electricity intensive industries find it very difficult to cope up with higher electricity charges particularly with time-of-use (TOU) tariffs implemented by the utilities with the objective of flattening the load curve. Load management programs focusing on reduced electricity use at the time of utility's peak demand, by strategic load shifting, is a viable option for industries to reduce their electricity cost. This paper presents an optimization model and formulation for load management of continuous process industries. The case study of a chemical industry is taken for conducting load management study. The formulation utilizes nonlinear programming technique for minimizing the electricity cost and reducing the peak demand, by rescheduling the loads, satisfying the industry constraints. Development of a generalized graphical user interface (GUI) in Visual Basic for implementing load management actions in industries and testing the GUI with the case study are done. Real time implementation of load management actions using Programmable Logic Controller (PLC) is also investigated.

This paper aims to realize an in-situ quality inspection system rapidly for new injection molding (IM) tasks via transfer learning (TL) approach and automation technology.

The proposed in-situ quality inspection system consists of an injection machine, USB camera, programmable logic controller and personal computer, interconnected via OPC or USB communication interfaces. This configuration enables seamless automation of the IM process, real-time quality inspection and automated decision-making. In addition, a MobileNet-based deep learning (DL) model is proposed for quality inspection of injection parts, fine-tuned using the TL approach.

Using the TL approach, the MobileNet-based DL model demonstrates exceptional performance, achieving validation accuracy of 99.1% with the utilization of merely 50 images per category. Its detection speed and accuracy surpass those of DenseNet121-based, VGG16-based, ResNet50-based and Xception-based convolutional neural networks. Further evaluation using a random data set of 120 images, as assessed through the confusion matrix, attests to an accuracy rate of 96.67%.

The proposed MobileNet-based DL model achieves higher accuracy with less resource consumption using the TL approach. It is integrated with automation technologies to build the in-situ quality inspection system of injection parts, which improves the cost-efficiency by facilitating the acquisition and labeling of task-specific images, enabling automatic defect detection and decision-making online, thus holding profound significance for the IM industry and its pursuit of enhanced quality inspection measures.

The purpose of this paper is to develop a coiling robot in the production of coated elevator compensation chains to replace the manual coiling operations and improve the quality of compensation chains.

This paper introduces both mechanical and servo control system designs of the coiling robot. The structure of two friction wheels stabilizes the conveying speed of compensation chain, so the chain speed matches with the car speed. A centering mechanism pushes the chain to its original position. Seven servo motors are integrated into the system, and they are controlled by a servo control system based on programmable logic controller, positioning controller, analog output block and touch screen.

The results of the project show that the coiling robot can both greatly reduce the number of workers and the intensity of the work and improve the quality of the chain. The chain lid by the robot is not only neat, but also uniform in its inner stress.

When the output speed of the compensation chain from the rear friction wheel does not match the coiling speed, the coiling operation has to be halted. Then, the operator adjusts the chain speed and restarts the coiling operation.

The coiling robot is proven working. It has been adopted by a leading company manufacturing compensation chains.

This is the first coiling robot which is practically used in a production line of compensation chains. Its design, mechanism and control systems are of great reference values to people.

The ‘cut‐spray’ stage in glass‐reinforced plastic processing has been automated by using the robot as a peripheral of a PLC.

This paper aims to describe a new methodology for controlling highly flexible automated manufacturing cells for use in aerospace manufacturing and repair.

The design methodology and rational of the FLEXA control architecture are described along with it implementation and testing.

The trials completed so far show that the level of flexibility required can be achieved both at factory, or enterprise level, and at shop floor level.

This work has significant practical implications through its direct applicability for aerospace and other automated manufacturing processes.

The originality of the paper lies in the truly flexible nature of the control system described and its ability to mimic traditional cell control architectures but be expanded through the use of virtual Programmable Logic Controller to control any number of cells without the need for significant extra hardware.