Measurement Problems of Space Vehicle Experiments

The need for conducting remote measurements by use of experimental sensors on space vehicles, in an environment where there is often a large uncertainty in the parameter to be measured, establishes a new area of endeavor for the researcher. The conditions peculiar to this problem are in many instances vastly different from those normally encountered in laboratory research, and are related to the over-all spacecraft design requirements. These new conditions attach a new significance to calibration philosophy, sampling rates, conversion accuracies, and reliability. Furthermore, the ground data handling problem of extracting information from the large quantities of data is extremely severe and usually requires careful planning by the experimenters several months prior to the actual measurement. The purpose of this paper is to survey the current and future aspects of acquiring accurate and intelligible information from the spacecraft sensors by the utilization of techniques which tend to be more compatible with the spacecraft design requirements.