Hi! Brand new to the forum, and fairly new to Arduino.
We're working though a simple hand model that uses flexinol wires to contract the fingers. Want to run it off the Arduino to write some code for it rather than using the kit controller. Anyway....when we feed power through the 3.3v or 5v connection, we get instant results. When we run it off a digital port, running, something simple like a blink sketch, we get nothing, or just a little bit of almost invisible twitching....any ideas about what might be going on much appreciated!
What is the mechanism by which muscle wire contracts? The phase transition. What causes the phase transition? A change in temperature. How do we get the change in temperature? By passing enough current through the wire that it heats up. That's a lot more current than an an IO pin on a microcontroller can supply; you need to drive it with a transistor. You'll need to sort out parameters like supply voltage to the muscle wires to get the desired behavior. The manufacturer may have provided some guidance on this.