These years have witnessed increasing research works and new technologies on manufacture of micro-/nanoscale flexible and tractile electronic devices. Orderly bead-on-string microstructures fabricated by electrospinning processes have applications in flexible and tractile sensors, artificial tissues and energy harvesters. In this paper, a feedback control system is established for sedimentary microstructures produced by electrospinning processes. This system is composed of a high-speed camera, an National Instruments (NI) image processor, an NI controller, and a linear machine regulating the substrate velocity. A robust model predictive control (MPC) method is developed on practical electrospinning processes to improve the regularity of the sedimentary bead-on-string pattern suffered by external disturbances and system uncertainties. Extensive experimental results have verified that the interbead gap becomes tunable and stabilized by the closed-loop MPC controller actuated by the linear machine. This controller is beneficial to enhance the consistency and controllability of the microelectrical elements. More significantly, the adjustability of the interbead gap enables the manufacturing of uniform microstructures widely used in microscale sensors and electrical units manufacturing and tissue engineering.