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Multi-Purpose Manipulator

A multi-purpose manipulator suitable for use in decommissioning work at Sellafield in Cumbria had to meet the individual requirements of four separate BNFL project teams. They laid down widely differing configurations for each task, and produced a joint specification which could be met by only the most versatile robotic arm. The unit had to combine unparalleled functionality and a very wide combination of modules and interconnecting sleeves to meet tasks with differing reach requirements, space envelopes and payload sizes. Value engineering was also vital, in terms of parts manufacture, through-life maintenance and in-service requirements. Understanding and interpreting the developing needs was key to meeting the requirements. Image showing Commander the multi-purpose manipulator.

Assystem demonstrated an ability to meet all those needs with the Commander robotic arm.

Commander is specifically designed for hazardous environments and offers six degrees of freedom. Its high strength and the use of hydraulic vane actuators to power the main joints, enables heavy payloads to be manipulated throughout the complete working envelope.

Commander's servo actuators communicate with the servo controller determining the attitude of each joint and response to commands. In addition, the UK Robotics ATC controller calculates in real time the geometry necessary to give resolved tip motion, and provides the operator with a high level of feel. True force feedback is available through the advanced servo controller design.

A control station offers joystick control of individual joints, while an interactive servo control system, compatible with most proprietary kinematic controllers, maintains accuracy and stability under all conditions of load and geometry.

Heavy Duty Manipulator
  • Commander provides full manipulation of 120kg at a maximum reach of 2.4 metres and can be configured up to 4.2m in length.
  • Hydraulic operation utilising either water/glycol or mineral oil

Versatile Modular Design
  • Commander can be reconfigured for tasks with differing reach requirements, space envelopes and payload sizes
  • Additional modules and extension tubes can be backfitted
  • Quick change modules keep manipulator downtime, and therefore project costs, to a minimum
  • Tool change interface is remotely operable

Off-the-Shelf Dexterity, Power and Repeatability
  • Capable of undertaking pre-programmed tasks with high positional accuracy and stability
  • The standard servo-control system supplied is compatible with most proprietary kinematic controllers
  • Incorporates high level controllers for ‘teach & repeat’ operations and resolved tip motions

Large Working Envelope with Fewer Degrees of Freedom
  • Vane actuators permit a compact design with minimum access requirements capable of deploying through a 270mm access penetration
  • This increases the effective range of each joint, resulting in a working envelope comparable to alternative systems with greater Degrees of Freedom
  • Lift off slave arm option

Smooth Lines
  • Ease of surface decontamination
  • No cavities to accumulate particle debris

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