Hi Guys,

I am interested in building a linear stepper motor. Its for a linear compressor I want to make.

In simple terms I want to use a linear motor (stepper) to move the piston up and down.

The piston is only 16mm wide and has an anticipated stroke of 16mm hence the stepper motor has to move the piston up16mm and then down 16mm.

I had the idea of placing a couple of coils around the shaft (like a solenoid) and then use a magnet in the shaft.

My problem is that I don't fully understand the stepper motor principle as it applies to a linear situation. I was thinking I could put two or more coils next to each other and perhaps one magnet with N and S at each end.

Could someone assist me with a quick explanation and a configuration that would be precise. The motor should operate at 12 volts and 100 watts.

Kind Regards

Simon