Intelligent Systems And Their Societies Walter Fritz



Air cylinders have been chosen for the function of muscles since they are relatively light and strong. Commercial air cylinders were discarded because we could not find cylinders of low enough weight. Low weight is required since some cylinders are located at the arms and legs. When these are heavy, movement is difficult and imprecise.

Cost for materials for the air cylinders: 955 dollars
Cost of 48 "DYNAMCO" D112201 (3/2) air valves with manifolds: 1365 dollars
Cost of pneumatic connectors and dia. 4 mm tubes: 346 dollars
Total pneumatic cost: 2666 dollars

Total shop hours for building the air cylinders and attachments to the skeleton (including grinding the cylinder tubes), valve supports and assembly : 330 hrs.
These are shop hours and do not include design and purchasing time.

Total weight of skeleton and air cylinders and valves: 17 kg (38 lbs).

Construction of air cylinders started June '98 and finalized Sept '99.

I could not find an air compressor of about 200W power, and did not want to build one myself using an electric motor connected to a modified airplane model engine. So I bought a big stationary air compressor connected to Robby with a 4mm (5/32") diameter tube. It looks to me that that is good enough for tryouts.


Here are some pictures:
- Robby sitting (For continuous reading, like a book - do not enter here now).
- Robby "standing" (Enter for continuous reading, like a book).


A drawing of a typical air cylinder:
Calf Cylinder (Enter for continuous reading, like a book).
This cylinder has a force of 100 kg (220 lbs).
Its stroke is 3.9 cm (1.5 inches).
Its weight is .42 Kg (.8 lbs).


For continuous reading, like a book - continue here.
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Last Edited 25 Abril 2013 / Walter Fritz
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