Abstract: The present invention provides a method and apparatus for controlled burning of experimental solid fuel test strands. The fuel test strand is advanced by a screw attached to a computer-controlled stepper motor. The stepper motor controls the fuel test strand position via a proportional-integral-derivative (PID) control loop, adjusting velocity based on transmission of a diode laser beam located at the desired fuel surface position. This provides real-time monitoring of fuel strand position and fuel regression rate during combustion experiments.