Search results

Reports on the proceedings of the 26th ISIR (International Symposium on Industrial Robots) held in Singapore, October 1995 and on the 4th Asian‐Pacific Industrial Automation Exhibition (IA ’95) held in conjunction with it. Subjects included addressing robot technology to service jobs – a potentially greater marketing sector than manufacturing; the future of robotics in Asia; and robot technology for medium and small companies.

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.

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 accurate measurement of the position and orientation of a robot end‐effector is the most critical issue for calibrating of robotic devices. Calibration methods provide tools to improve the accuracy of robots without modification to the mechanical unit or its control architecture. However, such calibration techniques require a large number of measurements. Dynamic measurement of position and orientation not only provides a solution to this problem, it also establishes the foundation for development of techniques to improve the robot’s dynamic accuracy. The concept of laser‐interferometry‐based measurement has been proposed. A system based on this concept is generally referred to as a laser tracking system (LTS). This paper describes the principle of laser‐interferometry‐based tracking. Further, the structure and various components within such a system are presented. A kinematic model for laser tracking is described and the performance of the system in its present configuration is presented. The application potential of such an approach to position and orientation (pose) measurement is also briefly described.

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.

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 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.

Notes that there are many areas where fine positioning of a robotic device carrying a specialized end‐effector is required. Describes a mechatronic wrist unit with fine motion capabilities for such applications. The wrist unit was designed as a four‐axis system with three revolute and one prismatic. The implementation is carried out in two stages. In the first stage, one prismatic axis and one revolute axis are implemented. Focuses attention on the underlying techniques for the development of this wrist unit given the requirements for weight and accuracy. Also describes the actuation mechanism and control strategies for the mechatronic wrist unit. Also presents the results of the experiments carried out for performance analysis.

Increasingly, the laborious task of removing burrs on castings is being automated with the introduction of robots. This is largely to ensure higher level of consistency and efficiency generally not possible with manual fettling. These burrs are unpredictable in size and shape, and if not removed, can lead to major problems in automated factory lines. Fettling is an important area in advanced robotic applications. This paper presents a strategy using a compliant wrist unit to obtain forces during robotic fettling. A specialised fettling wrist unit incorporating a remote centre of compliance (RCC) unit and a CCD camera is described. Experiments are carried out to evaluate the feasibility of this method. Fettling experiments are also performed using a force/torque sensing unit. A comparison of the results of these experiments is provided. The process parameters for fettling are described and relationships among these are established.

Describes the current research into vision‐based control of remotely controlled vehicles. The research at Robotics and Mechatronics Research Laboratory (RMRL), Monash University, Australia, aims to establish the foundation for future studies in control actions on levers and joysticks for guiding remotely operated vehicles. Use is made of a remote‐controlled car which is tracked by an overhead camera. A frame grabber is utilized to process the images and pass the necessary information about the relative position of the vehicle to the computer. Two servo‐driven mechanical arms are controlled to move the joysticks on the remote control unit. Focuses attention on simplified strategies for tracking and the subsequent control of such vehicles. Describes experimental facility comprising of the mechatronic components and their integration within this research‐based apparatus. Also presents future work in this area.