[Justin Stiltner]

Another issue may be the voltages that are usually applied to them, I rember when I built an stakito (sp) robot that used theise it reccomended around 3v, (9 was waaay too much applied directly to it, it would nearly jump but dident last very long) and when it is used in robotics I seem to rember that you apply an higher voltage for a very short time to get it to contract then lower the voltage to keep it hot and contracted.... such as 3v to start then lower to 1v in about .5 sec or so. While resistors are allowed in the materials list, they are only allowd in the custom boards that can only attach to the sensor inputs or serial port of the rc, not inline with the power. Altho like AL said, you may be able to use an speed controller to do this with PWM.