Micro and Nano-technologies need precision machines that can produce motion accuracy down to micro/nano-meter range. At the same time, these machines have to operate at high speeds to yield high productivity. Such an increasingly tight control performance requirement puts a significant challenge to control community and forces control engineers to look beyond traditional linear control theory for more advanced nonlinear controllers. This research is to present an advanced nonlinear adaptive robust control approach to achieve micro/nanometer level positioning accuracy for micro/nano-manipulation type applications. In addition, the proposed control strategy is implemented on a commercial linear motor drive system with a position measurement resolution of 20 nanometers by an external laser interferometer. Experimental results for both long-range high-speed/high-acceleration motions and short-range slow motions are presented to demonstrate the precision motion that can be achieved by the proposed method and various practical issues that remain to be solved. It is found that for motions with a maximum speed of 2 m/sec and maximum acceleration of 45 m/sec2, the steady state position tracking error is within the linear encoder resolution of 0.5 μm when the system comes to a stop and within 5 μm during the 2 m/sec constant speed period. Furthermore, the maximal position tracking during the entire motion is mostly within 20μm. For slow motions with a maximal speed of only 0.0002m/sec, the steady state position tracking error with the external laser interferometer position measurement is mostly within 0.1 μm when the system comes to a stop and within 0.2 μm during the constant low speed period, and the maximal position tracking during the entire motion is within 2μm.

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