Festo muscles-up with contraction drive solutions

Citation

(2002), "Festo muscles-up with contraction drive solutions", Industrial Robot, Vol. 29 No. 4. https://doi.org/10.1108/ir.2002.04929daf.005

Festo muscles-up with contraction drive solutions

Festo muscles-up with contraction drive solutions

Keyword: Pneumatics

Traditional pneumatic linear actuators now have competition from Festo's new fluidic muscle, Type MAS, which employs a novel approach to precise and repeatable linear displacement technology. The muscle, with its unconventional design, utilizes the unique concept of material deformation and flexure to achieve linear motion. This provides designers with an alternative, efficient both in relative size and weight, while also providing up to ten times more force than conventional cylinders (Plate 5).

The fluidic muscle employs a membrane-contraction system, which takes advantage of the same principle as human muscle. The basic concept involves the wrapping of a watertight, flexible hose with non-elastic fibers arranged in a rhomboidal fashion. This results in a three-dimensional grid pattern, and when compressed air is introduced into the system, the grid pattern is deformed. A pulling force is generated in the axial direction, resulting in a shortening of the muscle as internal pressure is increased.

Due to the relationship between the output force and the stroke of the fluidic muscle, it is difficult to compare it to traditional pneumatic cylinders. The MAS fluidic muscle offers a dramatic weight advantage. The overall weight is only about one eighth of the weight of a metal cylinder of equal inner diameter. Nevertheless, the force is up to ten times greater. Very slow movements are possible because the fluidic muscle is not encumbered by stick-slip effect, and dynamic performance is very high. Positioning tasks can be performed with a simple change in pressure, but an independent guide system for the load is required. End position cushioning is integrated. Unlike conventional pneumatic cylinders, the stroke range of the fluidic muscle is typically 25 per cent of its physical length.

Plate 5 Pneumatic muscle

The fluidic muscle product range includes 10mm, 20mm and 40mm inner diameter tubing, and overall lengths from 40mm to 9,000mm (almost 30 feet), including connectors. Suitable accessories are available for attaching the parts to be moved to the muscle, such as rod clevis and flexible couplings.

The fluidic muscle demonstrates a whole series of other interesting characteristics: flexible movement characteristics, variable installation possibilities, no mechanical wear, less sensitive to contamination, resistant to many media and minimal compressed air consumption, as well as leak-free performance and easy transport. Areas of application thus span a broad range from stationary or mobile industrial use, up through consumer related applications.

For further information contact Festo Corporation, 395 Moreland Road, PO Box 18023, Hauppauge, NY 1 1 788, USA. Tel: 631 435 0800; Fax: 631 435 8026.