Air Temp Nitinol

[Reiyuki]

Nice find Smokey.  Unfortunately it looks like the Java calculator link is dead, so I guess we'll just have to do it by hand 

This is the setup I'm going with.  A simple 115degF trained spring and a variable attachable mass.

For temperature control, I'm still deciding whether to just use current to contract the coil, or whether to go with a pump and controlled temperature water-drizzle system.  I'm concerned that simply attaching a thermocouple to the spring could lose a good deal of measurement precision.  Oh well, we'll just have to see.

[tak22]

You can learn a lot from these two sources, in particular the first one is a full teaching and learning package (TLP) that introduces the phenomena of superelasticity and the shape memory effect. It has quite good graphics and animations.

https://www.doitpoms.ac.uk/tlplib/superelasticity/shape_memory1.php

http://www-2.unipv.it/compmech/dissertations/zanaboni.pdf

The International Organization on Shape Memory and Superelastic Technologies (SMST) is a volunteer organization made up of industry professionals, scientists and researchers dedicated to disseminating technical education on the unique class of materials which exhibit shape memory and superelastic properties. http://www.asminternational.org/web/smst/home


tak

[ramset]

Good stuff indeed !!

setting up a wheel test bed for several experiments [including a floor twist drive off the axle

will be adding much more adjustability and other useful Gizmo's

Smoky has a recommendation for A crankshaft / Nitinol drive ,the pedal Assy will be a good test bed there. [the other half of Bike]

will be good to get the Kids interested in magnets , gravity /balance and nitinol/SMA  drive mechanisms ...especially now that I cut their bike in half 

Naahhh only kidding [its mine...
will be fun indeed !!

[sm0ky2]

Nice find Smokey.  Unfortunately it looks like the Java calculator link is dead, so I guess we'll just have to do it by hand 

This is the setup I'm going with.  A simple 115degF trained spring and a variable attachable mass.

For temperature control, I'm still deciding whether to just use current to contract the coil, or whether to go with a pump and controlled temperature water-drizzle system.  I'm concerned that simply attaching a thermocouple to the spring could lose a good deal of measurement precision.  Oh well, we'll just have to see.

Using electricity to actuate the SMA's is abundantly inefficient.
It has niche market value in robotics, but these robots use a lot of energy.
Something to the tune of 12v / 2 A (20-25 Watts)
Where-as raw temperature differences of ~20-40 degrees can do the same thing.

[ramset]

will be including experiments with Shape memory Polymers too
and low temperature Phase change gasses or gasse which react to charge on the off balance wheel too  [looking for a link from Dow ?

https://www.youtube.com/watch?v=VQqpnAKf9cM 

to be clear ...all will be to teach the kids the "what ifs" and get them away from The Mind numbing ...hand held mental handcuffs which are making them into Drones...

obviously there will be other threads here as these experiments get sorted

we have amazing resources in this open source community ,and many wonderful experimenters ,engineers and scientists

respectfully
Chet K