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This paper proposes a new control policy for optimal control of the 3-phase system of PEMFC connected to the grid. This also includes a 3-phase high step-up Interleaved Boost Converter (IBC) to amplify the PEMFC outputted voltage. To control the PEMFC system, Maximum Power Point Tracking (MPPT) based on Rigdelet Neural Networks (RNN) has been utilized, and to improve this controller, an improved version of the Satin Bowerbird Optimization (ISBO) algorithm has been utilized. The main advantage of the proposed improved version is modifying the convergence weakness and fixing convergence in chaos theory. The method is then validated by performing it one time on a standalone PEMFC system and another time on a grid-connected PEMFC system. Simulation results indicate that based o the IBC converter, better results with lower current ripples can be achieved. Also, the method has the ability to feed to both active and reactive powers by keeping stable the sudden temperatures. Final results have been also put in comparison with two different latest techniques to indicate the technique proficiency.

In computer-controlled optical surfacing (CCOS), the paths of the lap tools are limited inside the optical surface; this restricts convolution in the dwell-time algorithm and causes mid-spatial-frequency surface errors. An optimized strategy ensuring relatively complete convolution of the dwell-time algorithm is developed to control the mid-spatial-frequency surface error and simultaneously ensure high optical manufacturing efficiency. Different-sized lap tools are then introduced to correct the surface error in different areas of the optics. Simulations and experiments using a large off-axis SiC mirror demonstrate the validity of the strategy, and it could be widely applied to CCOS in grinding or polishing processes.

Magnetorheological finishing (MRF) fabrication can effectively facilitate a rapid fabrication of an aspherical 2 m reaction-bonded silicon carbide mirror. The dwell-time algorithm and tool path supported tool-mark mitigation and virtual-axis employment are analyzed. A rapid-fabrication strategy alternates MRF and a large polishing lap to converge surface error profile before MRF alone is used to high-precise finishing. In the alternate-use process, large polishing lap’s dwell time map for low-order space frequency is calculated before MRF’s for high-order one, but executed later in reality. The fabricated mirror with a silicon modification layer showed accuracy convergence from 0.098 λ rms to 0.019 λ rms at 84.6 h, demonstrating the strategy’s validity for large optical-surface processing. Keywords: Computer controlled polishing, Silicon carbide mirror, Surface error, Magnetorheological finishing, Large polishing lap