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Presents a robot control system dedicated for grinding and deburring robots. The control system is based on an active force feedback system using three axes force sensor attached to the robot’s end effector. This system offers new functionality in rapid programming of the robot by applying automatic programming and force supervision. The system is implemented and tested experimentally on a MultiCraft 560 robot with parallel kinematics. The experimental results show a significant reduction in the programming and set up time compared to conventional robot control systems.

This paper aims to purpose an improved sensorless position-based force controller in gravitational direction for applications including polishing, milling and deburring.

The first issue is the external force/torque estimation at end-effector. By using motor’s current information and Moore-Penrose generalized inverse matrix, it can be derived from the external torques of every joints for nonsingular cases. The second issue is the force control strategy which is based on position-based impedance control model. Two novel improvements were made to achieve a better performance. One is combination of impedance control and explicit force control. The other one is the real-time prediction of the surface’s shape allowing the controller adaptive to arbitrary surfaces.

The result of validation experiments indicates that the estimation of external force and prediction of surface’s shape are credible, and the position-based constant contact force controller in gravitational direction is functional. The accuracy of force tracking is adequate for targeted applications such as polishing, deburring and milling.

The value of this paper lies in three aspects which are sensorless external force estimation, the combination of impedance control and explicit force control and the independence of surface shape information achieved by real-time surface prediction.

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.

French aerospace company SNECMA has just installed its second robotised blade deburring cell at the Gennevilliers site. Anna Kochan reports.

Force/torque sensing is very important for several automatic and industrial robotic applications. Basically, if precise control of the forces that arise from contact between tools and parts is required to successfully complete the automatic task, then a force/torque sensor is needed along with some force/torque control technique. In this paper we focus on force/torque sensing aspects applied to industrial robotic tasks. Concentrating on a particular type of force/torque sensor, we demonstrate how to use them and how to integrate them into force/torque control applications using robots. Finally, an industrial application is presented where force control was fundamental for the success of the task.

A force‐torque sensor developed by the Institute of Flight Systems Dynamics at Wessling, West Germany, is said to have proved to be of value in deburring and assembly tasks with robots.

Reviews robotic exhibits at the UK Automation and Robot (AandR) show held alongside the UK's major manufacturing product exhibitions owned by the UK Machine Tool Technologies Association (MTTA), including MACH 2002. A centrepiece of the AandR show was the “robot island” sponsored by British Automation and Robots Association (BARA) in which a variety of robot applications were demonstrated including machine tending, bin picking and plastic riveting. Some of the robot exhibits in the MACH and Metalworking shows are also described including applications of press brake tending and deburring.