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Fettling is the process of removing excess material from castings. This excess material is often formed at the die’s parting lines during the casting process as molten material is injected into the die at high pressure. By using a robot as a positioning tool for the fettling operation, the process can be carried out safely and with consistent results. This paper proposes a computer‐assisted robotic fettling technique using visual feedback. In particular, emphasis is placed on the establishment of a technique and investigating its performance for the determination of the casting profile. Also examines the process parameters associated with high‐speed fettling operations. Further, the experimental set‐up employed and the results obtained are also presented.

Flexible fixturing is an important aspect of any flexible manufacturing system (FMS) and computer integrated manufacturing (CIM) environment. The production analysis for fixturing within an FMS environment is presented. Various approaches to flexible fixturing are briefly described. The reconfigurable fixturing is one of the most appropriate flexible fixturing techniques for CIM environment. Reconfigurable and/or automated modular fixturing employs a number of fixture modules that are set up, adjusted and changed to form different fixture layout. The requirements for locating and constraining workpieces are presented. In addition, computer‐aided planning and analysis of fixture set up are discussed.

Examines research work into the design and development of low‐to‐medium volume production systems. Outlines the aim to design a production unit capable of manufacturing a family of products, with a minimum amount of manual intervention. Investigates the use of flexible fixturing strategies using sensor‐based assembly techniques, and the concept of using modular fixture kits to locate and constrain the workpiece, including programmable conformable clamps. Looks at various assembly techniques and commercially available systems. Concludes that a number of novel assembly systems have been proposed and developed in the laboratory but that further research is needed to develop more advanced fixture design, task‐planning and analysis systems.

The objective is to develop a flexible robot assembly system capable of economically switching between a wide range of product assemblies. Towards this goal, this paper introduces grasping as a principle issue in designing for flexibility in a robot system. The task, sensing, and certainty about actions are the primary factors in grasp decisions and not where to grasp the part. Identifying finger features, which satisfy a broad range of tasks reduces the likelihood of re‐tooling, and improves certainty about part location and relative orientation. Aided by the ability to address a broad range of tasks, design rules are established which assimilate grasps to part design.

The industrial robot has high repeatability but low accuracy. With the industrial robot being widely used in complicated tasks, e.g. arc welding, offline programming and surgery, accuracy of the robot is more and more important. Robot calibration is an efficient way to improve the accuracy. Previous methods such as using coordinate measurement machines, laser trackers or cameras are limited by the cost, complex operation or the resolution. The purpose of this paper is to propose an approach and calibration equipment to address these issues.

The proposed method relies mainly upon a laser pointer attached on the end‐effector and single position‐sensitive devices (PSD) arbitrarily located on the workcell. The automated calibration procedure (about three minutes) involves aiming the laser lines loaded by the robot towards the center of the PSD surface from various robot positions and orientations. The localization is guaranteed by precise PSD feedback servoing control, which means physically the intersections of each pair of laser lines (virtual lines) are on the same point. Based on the untouched single‐point constraint, the robot joint offset calibration is implemented. Using the authors' proposed approach, a portable, low‐cost, battery‐powered, wireless and automated calibration system was implemented. Error analysis was conducted on the system.

The localization error of the developed calibration system is within 2 μm. The errors in joint space are magnified in PSD plane, and consequently the resolution in the joint space is improved. The standard deviation of the identified parameters was small (10‐2), indicating the stability of the calibration method. Both simulation and experimental results verify the feasibility of the proposed method and demonstrate the developed calibration system can identify joint offset with uncalibrated laser tool parameters.

The paper shows how a portable calibration system for joint offset of industrial robots was developed and how the goal of fast, automated, low‐cost, portable, and high precision calibration methods for joint offset was achieved.

The purpose of this paper is to introduce a method for stiffness modeling, identification and updating of collaborative robots (cobots). This method operates in real-time and with high precision and can eliminate the modeling error between the actual stiffness model and the theoretical stiffness model.

To simultaneously ensure the computational efficiency and modeling accuracy of the stiffness model, this method introduces the finite element substructure method (FESM) into the virtual joint method (VJM). The stiffness model of the cobots is built by integrating several 6-degree of freedom virtual joints that represent the elastic deformation of the cobot modules, and the stiffness matrices of these modules can be identified and obtained by the FESM. A model-updating method is proposed to identify stiffness influence coefficients, which can eliminate the modeling error between the actual prototype model and the theoretical finite element model.

The average relative error and the cycle time of the proposed method are approximately 6.14% and 1.31 ms, respectively. Compared with other stiffness modeling methods, this method not only has high modeling accuracy in high dexterity poses but also in low dexterity poses.

A hybrid stiffness modeling method is introduced to integrate the modeling accuracy of the FESM into the VJM. Stiffness influence coefficients are proposed to eliminate the modeling error between the theoretical and actual stiffness models.

Novel nanomaterials and nano-devices require further functional aspects that can be designed and supported using new nanomanipulation techniques allowing specific functions at the design phase. The nano-manipulator becomes a key instrument for technology bridging sub-nano to mesoscale. The integration of various operations in nano-devices requires sub-nanometer precision and highly stable manipulator. This paper aims to review various design concepts of recent nanomanipulators, their motion characteristics, basic functions, imagine and automation with control techniques for the sake of establishing new design features based on recent requirements.

The paper reviews various existing nanomanipulators, their motion characteristics, basic functions, imagine and automation with control techniques. This will support precision machine design methodology and robotics principles.

The availability of a nano-precision instrument with integrated functions has proved to be extremely helpful in addressing various fundamental problems in science and engineering such as exploring, understanding, modeling and testing nano-machining process; exact construction of nano-structure arrays; and inspection of devices with complex features.

New functional specifications have emerged from this review to support the design and make of new advanced nanomanipulators with more features availability to support manipulation within the same reference datum needed for research and education.

Laser interferometry‐based sensing (LIS) technique has been proposed and established recently to track and perform dynamic measurements on a moving end‐effector of a robot manipulator. In this paper, a technique using LIS system to perform guidance of a manipulator is proposed. The LIS system is used as a sensor to guide the end‐effector of a robot manipulator. This is to be accomplished through the implementation of guidance error determination and compensation, and path generation in the control algorithm. This technique can be used to accurately guide the manipulator’s end‐effector to a specified location or along a specified path with a high level of accuracy. The structure and various components within the system and the control strategy are also presented.

The objective of this paper included developing a polar robot (SPBot) for rotating and transferring car engine block (CEB) around and along two different axes in a confined workspace envelope.

The complex transfer operations of the CEB requires sweeping complete surface of the half sphere, and thus a polar robot is best suited to such a task in a confined space. Considering the limited space for this operation, a specially designed manipulator is built comprising 2 degrees of freedom driven by electrical servo motors. Also due to the special form of CEB, an especially designed pneumatic gripper is developed. Kinematics models, static and dynamic equations, together with trajectory planning for such a manipulator are described.

The high‐speed complex transfer in a limited environment is successfully implemented.

The developed polar robot provides for complex transfer operations that significantly increases the speed of the product line and thus reducing the cycle time from 60 s using manpower to just 20 s using the robot.

The excellent material properties of fibre reinforced composites make them especially attractive for applications in the aerospace and automotive industries. Traditional methods of manufacturing composite structures have proven to be labour intensive and time‐consuming. Robotic fibre placement for fabrication of composite components has been proposed. This approach greatly reduces production cost and time. This paper briefly presents the overall strategy for the establishment of a robotic fibre placement facility. The methodology for development of process planning and programming, simulation, program generator and control is described. In addition, the algorithms for automatic fibre path generation for open and closed surfaces will also be discussed, as well as the control system architecture for the process.