Pneumatic muscle
A pneumatic muscle (fluidic muscle) is an actuator (work device) in pneumatics ( fluid technology ) and is used to perform faster work.
General
The pneumatic muscle is a membrane contraction system, also known as a tension actuator, which is modeled on the biological muscle (see also muscle contraction ). It consists of a pressure-tight tube with an integrated diamond-shaped mesh made of high-strength fibers. When pressure is applied to the contraction tube, it expands in the transverse direction and contracts in the longitudinal direction. The incorporated fibers are responsible for keeping the tube in shape and for limiting and stabilizing the expansion to a change in length (approx. 15-25%).
Since the muscle has no moving / shiftable parts, it works largely frictionless. This makes it possible to carry out uniform and very slow movements jerk-free without stick-slip effect , but also very fast and very high working frequencies. Due to the low mass or the very high force-to-weight ratio of the actuator, it is possible for it to achieve very high acceleration values of up to 50 m / s 2 and up to 10 times higher initial force compared to a cylinder of the same diameter. The usable tensile force has its maximum at the beginning of the contraction and decreases almost linearly with the stroke.
The "muscle" is designed as a pure traction system (single acting actuator) and is not suitable for tasks that use the movement in the circumferential direction. This could damage the pressure hose and it will no longer function reliably.
The nominal length is specified in the unloaded condition and corresponds to the visible hose length. The muscle expands through tensile loading / pretensioning, which allows it to develop its maximum force and contraction when pressure is applied.
When the external load changes, the muscle behaves like a spring and follows the direction of force. This means that it can also be used as a "pneumatic spring" with various " spring characteristics " which are determined by the air volume and the air pressure. The clamping force and rigidity can thus be optimally matched to the working conditions.
| Size | 10 | 20th | 40 |
| Inside , in mm | 10 | 20th | 40 |
| Nominal length, in mm | 40 ... 9000 | 60 ... 9000 | 120… 9000 |
| Max. Additional load, freely hanging, in kg |
30th | 80 | 250 |
| Max contraction allowed | 25% of the nominal length | ||
| Max. Hysteresis, in% of the nominal length |
≤ 3 | ≤ 25 | |
| Repeatability | ≤ 1% of the nominal length | ||
| Theoretical force, in N. | 630 | 1500 | 6000 |
Applications
It is used for quick tasks due to its design and the resulting advantages:
- Sorting and positioning tasks
- Clamping and gripping technology
- High speed cutting operations
- Emergency stop facilities
- Drive of punching tools
- Stick-slip- free movements
- Belt edge controls
- Belt tensioner
- Vibration exciter
The hermetically sealed interior makes it very suitable for the food industry or for dusty and dirty environments, as these external conditions do not impair the work of the pneumatic muscle.
See also
literature
- FESTO: Fluidic Muscle DMSP / MAS , 11/2009. Wikipedia World Press, ( PDF file; 1.0 MB )
- Prof. Dr.-Ing. D. Schmitt: Automation technology. 7th edition. EUROPA Lehrmittelverlag, Haan-Gruiten 2006, ISBN 3-8085-5157-7 , p. 130.
- Mathias Ruoss: Artificial muscles: Biologically inspired construction and functionality June 8, 2004, pp. 4–5 ( PDF file; 0.2 MB )