A new electrostatic probe method utilizing the triple probe is proposed in which no voltage or frequency sweep (or switching) is required. This feature enables us to determine the instantaneous values of the electron temperature (Te), as well as the electron density (ne), within a short time which is of the order of the intrinsic response time of the probe itself (⪝1μsec). Moreover, the system allows the direct display of the Te values as well as the semidirect display of the ne values on appropriate display units, thus permitting us to eliminate almost all procedures usually required for data processing. In view of the features mentioned, this system may be a useful diagnostic tool not only for stationary plasmas but also for rapidly varying time-dependent plasmas of various types. This paper presents theoretical considerations for the instantaneous direct-display system using a symmetrical triple probe. Discussions are also presented for the estimation of errors caused by the variation of ion saturation current, for the application to magnetoplasmas, and for the time and spatial resolutions. Experimental confirmation was made through the measurements of stationary magneto- as well as non-magnetoplasmas. As an example of the application to time-dependent plasmas, the electron temperature waves accompanied by the moving striations in hydrogen discharge were observed.

An exact theory taking the ion temperature T1 into account is developed for a triple-probe in an orbital-motion-limited collisionless plasma, i.e. when charged particle mean free path>>Debye length>>probe radius. Formulae for determining electron temperature and electron density are given for both spherical and cylindrical probes. Analytical results show that the effect of T1 on measurements of plasma parameters is small when using a cylindrical probe and is negligible when compared to the errors obtained when using a spherical probe. The magnitude of the errors obtained in practical measurements are discussed. The possibility of ion temperature determination using this theory is also suggested. Experiments have been also done for confirmation.

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Studies of the short-duration nitrogen pink afterglow (PA) are reported for different electrostatic probe types (spherical and cylindrical) and materials (Pt and Au). Various collision-dominated probe theories were applied to determine the electron density Ne and temperature Te. Experimental radial distribution curves are presented for the parameters kTe, Ie / Ii (electron to ion current ratio), and Ne at various points in the PA. An apparent increase in the ion current caused by emission of electrons from the probe surface was found to correlate with the light emission intensity of the first negative bands of N2+. kTe was found to be about 1 eV upstream of the PA in the dark space, reaching a maximum of nearly 4.5 eV before decreasing again to 1 eV downstream. The maxima in the axial profiles through the PA of Te, the light emission intensity and the ion current coincide, while Ne (in the range 1–5 × 109 cm−3) shows its maximum a few milliseconds later. The effect of impurities on the PA was examined. The role played by electrons in the process of PA formation is discussed.

This paper proposes a novel control approach for vehicle collision avoidance of urban vehicles. For safe driving in urban environments, this paper presents both one-dimensional and two-dimensional solutions, which can be applied to the collision avoidance via steering assistance, automatic braking, and warning of collision. Strategies are verified under the software CarSim, and the experimental evaluations are carried out under the combination of CarSim with a hardware-in-the-loop platform. The results show the feasibility and effectiveness of the proposed algorithm on vehicle collision avoidance.