ECE5320 MechatronicsAssignment#01: Literature Survey on Sensors and Actuators Assignment#01: Literature Survey on Sensors and Actuators

Pneumatic Artificial MusclesPneumatic Artificial Muscles(PAMs)(PAMs)

Prepared by:

Jeffrey TaylorA00815505

3/20/2012

03/07/12 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

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Outline – Reference list

– To probe further

– Major applications

– Basic working principle illustrated

– A typical sample configuration in application

– Major specifications

– Limitations

– Where to buy

03/07/12 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

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Reference listAir Muscle Actuated Low Cost Humanoid Hand http://cdn.intechweb.org/pdfs/4176.pdf

The Shadow Air Musclehttp://www.shadowrobot.com/airmuscles/overview.shtml

Seminar Paperhttp://www.seminarpaper.com/2011/12/seminar-report-on-air-muscle.html

Images Scientific Instruments http://www.imagesco.com/articles/airmuscle/AirMuscleDescription01.html

Journal of Applied Science in the Thermodynamics and Fluid Mechanicshttp://astfm.tul.cz/journal/year-2009/1st-issue/

03/07/12 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

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To explore further

Many websites show how to make your own air muscle from assorted pieces bought online.

Recommended:http://www.instructables.com/id/How-to-make-air-muscles!/

Additional:http://www.youtube.com/watch?v=AkaVsoEd6Vo

http://en.wikibooks.org/wiki/Robotics/Components/Actuation_Devices/Air_muscle

http://www.ehow.com/how_2257980_make-air-muscles.html

03/07/12 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

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To explore further

There is a great deal of research being conducted on the use of PAMs for use in prosthetics and mobile robots. These links provide a few of the current projects.

Recommended:http://www.instructables.com/id/How-to-make-air-muscles!/

Additional:http://www.youtube.com/watch?v=AkaVsoEd6Vo

http://en.wikibooks.org/wiki/Robotics/Components/Actuation_Devices/Air_muscle

http://www.ehow.com/how_2257980_make-air-muscles.html

03/07/12 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

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Major applications PAMs have a variety of

applications. They can be used to replace many pneumatic cylinders in traditional robotics and can be used to replicate biological systems in prosthetics.

http://mindtrans.narod.ru/walkers/legs/pictures/shadow_leg.JPG

03/07/12 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

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Major applications PAMs in conventional robotics.

http://30.media.tumblr.com/tumblr_ll3ihkz7jJ1qft3eko1_500.jpg

http://robotionary.com/wp-content/uploads/2010/10/festo-airacuda-the-new-pneumatic-muscle-fish.jpg

03/07/12 ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

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Major applications PAMs in prosthetics.

http://images.gizmag.com/inline/amoarm-2.jpg

http://www.amputation.research.va.gov/images/variable_stiffness_prosthetic_ankle.png

There are two main parts to an air muscle: a stretchable rubber and a braided mesh sleeve.

The rubber provides a chamber for the air.

The sleeve provides necessary strength against pulling forces.

Basic Working Principle

To contract the muscle, air is forced into the rubber, causing it to expand. Because the volume is fixed, the expansion causes an axial load.

Basic Working Principle

http://www.imagesco.com/articles/airmuscle/fig2.jpg

As air is vented, the rubber relaxes and the muscle returns to its original length.

Basic Working Principle

http://www.imagesco.com/articles/airmuscle/fig2.jpg

Sample ConfigurationsDue to the relatively low change in displacement,

mechanical amplifiers are typically used to increase the effective displacement.

http://www.imagesco.com/articles/airmuscle/fig10.jpg

Sample ConfigurationsTwo PAMs can also be used to create counter loads

for each other.

http://www.imagesco.com/articles/airmuscle/fig12.jpg

Sample ConfigurationsMore and more PAMs can be combined in a variety

of configurations to create highly mobile and versatile systems.

http://upload.wikimedia.org/wikipedia/commons/c/c5/Shadow_Hand_Bulb_large.jpg

Sample ConfigurationsEach PAM also requires a three way air valve and

some kind of pressure system.

http://www.imagesco.com/articles/airmuscle/fig13.jpg

Actuator Specifications

The specifications for a PAM can very

greatly depending on the material used for

the rubber membrane and for the mesh, the

length of tubing and mesh, the working

pressure of the system, etc.

Actuator SpecificationsBecause of the diverse

options provided by a PAM, the muscle can be made specifically for a given project. Some specifications to be aware of, however, are:

- Fully stretched length

- Fully contracted length

- Maximum pressure (both of rubber and fittings)

- Tightness of mesh weave

-

Actuator SpecificationsShadow Air Muscle as an example:

http://www.shadowrobot.com/airmuscles/overview.shtml

Pros of PAMs- Lightweight

- Low cost

- Smooth

- Flexible

- Damped

- Powerful

- Compliant

http://cdnimg.visualizeus.com/thumbs/3d/f3/baldwin,muscle,hydrostat,in,operation,mckibben,muscle,morin,muscle,pn

eumatic,muscle-3df3d5564e7402e3a21a71a76acbf55e_h.jpg

LimitationsThere are three major

limitations to an air muscle:

- how far it can extend

- how far it can contract

- extremely non-linearMODEL OF THE PNEUMATIC DOUBLE ACTING CYLINDER COMPILEDBY RHD RESISTANCES

Journal of applied science in the thermodynamics and fluid mechanicsVol. 3, No. 1/2009, ISSN 1802-9388

Where to BuyAs mentioned earlier, Shadow Robot Company

sales exceptional PAMs at a good price.

http://www.shadowrobot.com/images/sam30mm_pulling_nail_02.png

Can't Afford It? Build It.If you can't afford it, you can always build it by

following the links at the beginning of this presentation.

Here is what you'll need:

- Air source

- 1/4” high pressure poly

tubing

- 1/4” latex tubing

- 3/8” braided nylon mesh

- 1/8” small hose barb

- Small bolt

- Steel safety wire

And of course

- Safety goggles