Using the linear forces that are provided by an electromagnetic solenoid applied near the distal end of a medical catheter, various surgical instruments can be actuated or deployed for use in interventional medicine. The linear actuator uses the principles of magnetic repulsion and attraction as a means for moving a bobbin that can be attached to various types of moving components that translate linear movements into the actuation of a tool that is attached to the linear actuator. Using independent solenoid coils, movement modality is increased from two possible positions to three.