To restrain the zero drift of a piezoelectric accelerometer and the zero drift from a charge amplifier (CA) in an ultrahigh-g impact environment, a reformative design approach for an on-board ultrahigh-g deceleration-time measurement system is presented. First, a simplified zero-drift model of the on-board ultrahigh-g deceleration-time measurement system is built. Secondly, possible reasons for zero drifts in the ultrahigh-g impact environment are discussed. Then, a universal reformative CA and subsequent circuits are designed for restraining the zero drift. Finally, an air cannon is used to simulate the ultrahigh-g impact environment and a modified Michelson-type laser interferometer is set as a primary standard source to calibrate the reformative on-board measurement system. Comparisons between the measured curve and the reference curve verify that the zero drift is less than 3% of the peak value and deceleration-time data describe the real penetration process accurately. All differences in curves are not due to the proposed design and can be characterized by errors or uncertainties. Experimental results prove that the proposed design approach can restrain the zero drift effectively in the ultrahigh-g impact environment.

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The process of cell culture in space is very important, but nowadays, advanced space cell culture with imaging system is absent. To develop a new space microscope imaging system, the first thing for us is to analyze the space factors work on the system. So, in this paper, how the main space environment affect imaging system is presented. Firstly, the model of imaging system is shown, and modulation transfer function (MTF) is to describe the quality of imaging. Then, the influence of atmospheric pressure change, temperature change and machine vibration on imaging system is given. And, we build a relationship model between a single factor and MTF to express the influence of space factors. In the end, the correspondence design rule is given. This will be an important technical support for design space microscope imaging system.