Controlling shape memory alloys

Hello All,

I'm trying to use an Arduino to control a shape memory alloy. The SMA needs 3V to work. I'm using an ambient light sensor to control whether or not voltage is sent to the SMA. Ideally, when there is more light, more volts will be sent to the SMA. Currently I am using an LED in the place of the SMA and it works fine, but I'm not sure how to physically hook up the SMA to the breadboard and then write code for it. HELP PLEASE!

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