Faraday cup instruments for solar wind and interplanetary dust monitoring

Importance of solar wind monitoring for space weather applications increases with expansion of power networks and oils or gas pipelines to larger geomagnetic latitudes and development of new communication networks. Instruments based on Faraday cups are an ideal solution for these purposes because they are robust and their light weight and low power consumption facilitate their applications for a small spacecraft. Another important feature of Faraday cups is their capability of detection of impacts of interplanetary dust. Such instruments are currently a part of two planned ESA missions that will be briefly introduced. In the core of contribution, we describe the preliminary instrument design and concentrate on most important technical aspects of their development including a computer modeling of the most important parts of detectors. Among others, we present the effects of the grid geometry on the detector capability to determine the plasma velocity vector and temperature and search for optimum detector configuration for small spacecraft missions. We also discuss the data strategy allowing maximum scientific income with limited spacecraft telemetry.